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Archive for the ‘Organ-on-a-Chip’ Category

Digital Therapeutics: A Threat or Opportunity to Pharmaceuticals


Digital Therapeutics: A Threat or Opportunity to Pharmaceuticals

Reporter and Curator: Dr. Sudipta Saha, Ph.D.

 

Digital Therapeutics (DTx) have been defined by the Digital Therapeutics Alliance (DTA) as “delivering evidence based therapeutic interventions to patients, that are driven by software to prevent, manage or treat a medical disorder or disease”. They might come in the form of a smart phone or computer tablet app, or some form of a cloud-based service connected to a wearable device. DTx tend to fall into three groups. Firstly, developers and mental health researchers have built digital solutions which typically provide a form of software delivered Cognitive-Behaviour Therapies (CBT) that help patients change behaviours and develop coping strategies around their condition. Secondly there are the group of Digital Therapeutics which target lifestyle issues, such as diet, exercise and stress, that are associated with chronic conditions, and work by offering personalized support for goal setting and target achievement. Lastly, DTx can be designed to work in combination with existing medication or treatments, helping patients manage their therapies and focus on ensuring the therapy delivers the best outcomes possible.

 

Pharmaceutical companies are clearly trying to understand what DTx will mean for them. They want to analyze whether it will be a threat or opportunity to their business. For a long time, they have been providing additional support services to patients who take relatively expensive drugs for chronic conditions. A nurse-led service might provide visits and telephone support to diabetics for example who self-inject insulin therapies. But DTx will help broaden the scope of support services because they can be delivered cost-effectively, and importantly have the ability to capture real-world evidence on patient outcomes. They will no-longer be reserved for the most expensive drugs or therapies but could apply to a whole range of common treatments to boost their efficacy. Faced with the arrival of Digital Therapeutics either replacing drugs, or playing an important role alongside therapies, pharmaceutical firms have three options. They can either ignore DTx and focus on developing drug therapies as they have done; they can partner with a growing number of DTx companies to develop software and services complimenting their drugs; or they can start to build their own Digital Therapeutics to work with their products.

 

Digital Therapeutics will have knock-on effects in health industries, which may be as great as the introduction of therapeutic apps and services themselves. Together with connected health monitoring devices, DTx will offer a near constant stream of data about an individuals’ behavior, real world context around factors affecting their treatment in their everyday lives and emotional and physiological data such as blood pressure and blood sugar levels. Analysis of the resulting data will help create support services tailored to each patient. But who stores and analyses this data is an important question. Strong data governance will be paramount to maintaining trust, and the highly regulated pharmaceutical industry may not be best-placed to handle individual patient data. Meanwhile, the health sector (payers and healthcare providers) is becoming more focused on patient outcomes, and payment for value not volume. The future will say whether pharmaceutical firms enhance the effectiveness of drugs with DTx, or in some cases replace drugs with DTx.

 

Digital Therapeutics have the potential to change what the pharmaceutical industry sells: rather than a drug it will sell a package of drugs and digital services. But they will also alter who the industry sells to. Pharmaceutical firms have traditionally marketed drugs to doctors, pharmacists and other health professionals, based on the efficacy of a specific product. Soon it could be paid on the outcome of a bundle of digital therapies, medicines and services with a closer connection to both providers and patients. Apart from a notable few, most pharmaceutical firms have taken a cautious approach towards Digital Therapeutics. Now, it is to be observed that how the pharmaceutical companies use DTx to their benefit as well as for the benefit of the general population.

 

References:

 

https://eloqua.eyeforpharma.com/LP=23674?utm_campaign=EFP%2007MAR19%20EFP%20Database&utm_medium=email&utm_source=Eloqua&elqTrackId=73e21ae550de49ccabbf65fce72faea0&elq=818d76a54d894491b031fa8d1cc8d05c&elqaid=43259&elqat=1&elqCampaignId=24564

 

https://www.s3connectedhealth.com/resources/white-papers/digital-therapeutics-pharmas-threat-or-opportunity/

 

http://www.pharmatimes.com/web_exclusives/digital_therapeutics_will_transform_pharma_and_healthcare_industries_in_2019._heres_how._1273671

 

https://www.mckinsey.com/industries/pharmaceuticals-and-medical-products/our-insights/exploring-the-potential-of-digital-therapeutics

 

https://player.fm/series/digital-health-today-2404448/s9-081-scaling-digital-therapeutics-the-opportunities-and-challenges

 

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What could replace animal testing – ‘Human-on-a-chip’ from Lawrence Livermore National Laboratory

The iCHIP research, Moya said, could have implications for creating new drugs to fight cancer, vaccines or evaluating the efficacy of countermeasures against biowarfare agents.

Lab scientist Heather Enright is leading research into the peripheral nervous system (PNS), which connects the brain to the limbs and organs. The PNS device has arrays of microelectrodes embedded on glass, where primary human dorsal root ganglion (DRG) neurons are seeded. Chemical stimuli such as capsaicin (to study pain response) then flow through a microfluidic cap to stimulate the cells on the platform.

The microelectrodes record electrical signals from the cells, allowing researchers to determine how the cells are responding to the stimuli non-invasively. Microscopic images can be acquired at the same time to monitor changes in intracellular ion concentrations, such as calcium. This platform is the first to demonstrate that long-term culture and chemical interrogation of primary human DRG neurons on microelectrode arrays is possible, presenting researchers with an advantage over current techniques.

Read full article at the SOURCE

 

http://universityofcalifornia.edu/news/human-chip-could-replace-animal-testing

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AGENDA for Second Annual Organ-on-a-Chip World Congress & 3D-Culture Conference, July 7-8, 2016, Wyndham Boston Beacon Hill by SELECTBIO US

Reporter: Aviva Lev-Ari, PhD, RN

 

AGENDA for July 7, 2016

OOAC2016_600x176_3for2

Thursday, 7 July 2016

08:00

Conference Registration, Materials Pick-Up and Continental Breakfast in the Exhibit Hall


Session Title: Opening Plenary Session

09:00

Martin Yarmush Keynote Presentation

Organ-on-a-Chip Technologies: Advances and Challenges
Martin Yarmush, Paul and Mary Monroe Chair, Distinguished Professor of Biomedical Engineering, Rutgers University; Director, Center for Engineering in Medicine, Massachusetts General Hospital, United States of America

09:30

Linda Griffith Keynote Presentation

Move Over, Mice — How the Fusion of Systems Biology with Organs on Chips May Humanize Drug Development
Linda Griffith, Professor, Massachusetts Institute of Technology (MIT), United States of America

“Mice are not little people” – a refrain becoming louder as the strengths and weaknesses of rodent models of human physiology and disease become more apparent.  At the same time, three emerging approaches are headed toward integration:  powerful systems biology analysis of intra- and inter-cellular signaling networks in patient samples; 3D tissue engineered models of human organ systems, often made from stem cells; and microfluidic devices that enable living systems to be sustained and used for models like cancer metastasis.  This talk will highlight the integration of these rapidly moving fields to understand difficult clinical problems, and will especially highlight intellectual and technical challenges in transitioning “organs on chips” platforms from academic publications into practical use.

10:00

Roger Kamm Keynote Presentation

Creating Vascularized Tissue Constructs in Microfluidic Assays
Roger Kamm, Cecil and Ida Green Distinguished Professor of Biological and Mechanical Engineering, Massachusetts Institute of Technology (MIT), United States of America

Vascularization is critical to most tissues, yet developing a perfusable microvascular network within an on-chip tissue construct has proved challenging. Several approaches have been developed in recent years including the casting of networks within a hydrogel matrix that can subsequently be lined with vascular cells, and the growth of networks from cells seeded either on the surface of a hydrogel by angiogenesis, or from cells suspended in gel by a process akin to vasculogenesis.  Our previous work has followed the second path in producing networks within microfluidic platforms that can be perfused within several days of seeding.  These networks can be grown in various matrices either in co-culture with other cell types such as fibroblasts, myoblasts or osteoblasts, or in isolation.  To date, the best results have been obtained by co-culture with normal lung fibroblasts in separate gel regions, using a fibrin-based extracellular matrix.  Recently, these systems have been scaled up to mm-sized regions and the fibroblasts are co-seeded with the endothelial cells, leading to vascularized and perfusable networks that are perfusable for three weeks with potential applications for in vitro organ-on-chip systems.

10:30

Coffee Break and Networking in the Exhibit Hall

11:15

Geraldine A Hamilton Keynote Presentation

Organs-On-Chips for Advancing Drug Development and Personal Health
Geraldine A Hamilton, President/Chief Scientific Officer, Emulate Inc, United States of America

This talk discusses emulating living human biology to understand how different diseases, medicines, chemicals and foods affect human health. These systems are being used to advance product innovation, design and safety across a range of applications – including drug development, agriculture, cosmetics, chemical-based products and personalized health.

11:45

Michael Shuler Keynote Presentation

Using Human “Body-on-a-Chip” Devices to Aid Drug Development
Michael Shuler, Samuel B. Eckert Professor of Engineering, Cornell University; President & CEO, Hesperos, Inc., United States of America

Effective human surrogates constructed from a combination of human tissue engineered constructs, microfabricated devices, and PBPK (physiologically based pharmacokinetic) models offer a potential alternative or supplement to animal studies to make better decisions on which drug candidates to move into clinical trials. These systems have been called microphysiological systems. We have constructed “pumpless” systems that provide a low cost, relatively simple-to-use platform to evaluate potential drugs for human response. In addition to measuring viability and metabolic responses, we can measure functional outputs such as electrical activity and force generation (in collaboration with J. Hickman, University of Central Florida). We will focus our discussion on development of key organ modules and their integration into a model of the whole body.

12:15

Nancy Allbritton Keynote Presentation

Microengineered Systems for Recapitulating Intestinal Function
Nancy Allbritton, Professor and Chair, University of North Carolina, United States of America

Technical advances are making it possible to create tissue microenvironments on platforms that are compatible with high-content screening strategies. We have developed a microfabricated device to enable culture of organized cellular structures possessing much of the complexity and function of intact intestinal tissue.  Single stem cells or crypts isolated from primary mouse intestine grow and persist indefinitely as organotypic structures containing all of the expected lineages of the intestinal epithelium. Our microengineered arrays and fluidic devices allow prolonged culture and experimental manipulation of these intestine-on-chip systems.  Millimeter-scale primary intestinal epithelium can be formed closely mimicking the polarized 3D in vivo microarchitecture of primary tissue. These systems can also be interrogated by a variety of techniques including fluorescence, immunohistochemistry and genetic analyses. The bioanalytical platforms are envisioned as next generation systems for high-throughput assays of drug- and toxin-interactions with the intestinal epithelia.

12:45

Networking Lunch, Discussions with Exhibitors and View Posters


Session Title: Organs-on-Chips for Drug Discovery, Toxicity Screening and Drug Development

14:00

Organs on Chips for Drug development, Toxicology, and Systems Biology: A Distributed yet Interconnected Modular Approach
John Wikswo, A.B. Learned Professor of Living State Physics; Founding Director, Vanderbilt Institute for Integrative Biosystems, Vanderbilt University, United States of America

Organs-on-chips are undergoing rapid development to better recapitulate in vitro the function of human organs in vivo. Their application to a variety of fields suggests the need to create large numbers of different organs and operate them either independently or interconnected, or both. This places economic and topological constraints on the physical hardware systems that keep these organs alive, monitors their performance, and controls their interaction. A promising approach is to utilize different low-cost modules, made from a simple set of common components, to provide these functions in a plug-and-play manner, thereby spanning the range of applications of organs on chips pursued from organizations as small as a single-investigator biology lab to government toxicology screening programs to pharmaceutical groups evaluating the efficacy and toxicity of drugs and drug cocktails.

14:30

David Hughes Keynote Presentation

LiverChip – Development of Organ-on-a-chip Liver Disease Models
David Hughes, Chief Technical Officer, CN Bio Innovations Ltd., United Kingdom

Organ-on-a-chip (OOC) technologies offer the promise of in vitro models which more closely recapitulate the in vivo. Current OOCs typically have low to medium throughput, offer high information content and are relatively complex when compared to 2D cultures, making it more likely that these technologies could replace certain animal tests than supplant high throughput screens. An initial wave of activity focused on drug metabolism and safety applications of OOCs however an animal-centric regulatory framework, particularly for safety testing, and a disconnect between the cost and benefit that OOCs can provide in ADME/Tox make this a challenging area in which to achieve widespread adoption. Disease modelling provides a more compelling opportunity for OOC technologies: a number of diseases are poorly recapitulated in animal models so OOCs offering improved translational relevance would be highly desirable.  A small airway-on-a-chip to model COPD and asthma, and a hepatitis B infected liver-on-a-chip model are two examples of disease OOCs already being exploited by pharmaceutical companies in the development of new drugs. This presentation will describe the development of models for viral hepatitis, malaria and non-alcoholic fatty liver disease (NAFLD) building on a microfluidic OOC platform, LiverChip®.  Liver disease represents a significant and growing global health burden, being the only one of the top five causes of death to have increased in the UK in the last decade. The liver is a complex organ, comprised of multiple cell types undertaking hundreds of essential functions and is a major site of drug metabolism and toxicity. The liver is also a unique immunological organ in which liver resident macrophage (Kupffer) cells and lymphocytes play critical roles in first line immune defence against invading pathogens, modulation of liver injury and recruitment of circulating lymphocytes.

15:00

A Biochip-based Liver Organoid Model of Human Sepsis
Alexander Mosig, Lab Head, Biochip-based Organ Models, Jena University Hospital, Germany

Liver dysfunction is among the earliest events in sepsis-related multi-organ-failure. To date mostly animal models of sepsis are used to study the underlying molecular mechanisms. However, a controversial debate about usefulness of animal models was raised, questioning for their transferability to human conditions. We therefor developed a new microfluidically supported Biochip as scaffold for an in vitro organoid model of the human liver sinusoid, comprising vascular and hepatic cell layers. The biochip-based liver organoid integrates hepatocytes and non-parenchymal cells aligned in a bio-inspired fashion enabling physiological cross communication. In multi-layer approach of co-cultured vascular and hepatic cell layers we mimicked the in vivo situation in the human liver. The biochip design allows to study interaction of circulating immune cells with different layers of the liver organoid in real-time under flow conditions. The cellular events observed in the liver organoid thereby closely resembled to pathophysiological processes found in sepsis models of mice and in clinical observations of human sepsis. We therefore conclude that our liver-biochip organoid model is a valuable tool for studies of inflammation-related liver dysfunction. It will improve current research strategies on liver failure and contribute to fill the gap between animal experimentation and clinical human studies.

15:30

The Patent Landscape of Organs-On-A-Chip
Robert Esmond, Director, Sterne, Kessler, Goldstein & Fox P.L.L.C, United States of America

Organs-on-a-chip have present-day real-world uses such as for the preclinical testing of drugs. Thousands of patents have been filed on various aspects of organs-on-a-chip, including their manufacture.  A company seeking to make, use or sell an organ-on-a-chip must consider the patent landscape.  This talk will focus on ways to protect organs-on-a-chip innovation, patent filings directed to organs-on-a-chip technology, certain exceptions to patent infringement, as well as the possibility of future litigation.

16:00

Kristin Fabre Keynote Presentation

The NIH Tissue Chip Program: Current Progress and Future Initiatives
Kristin Fabre, Scientific Program Manager, NIH National Center for Advancing Translational Science (NCATS), United States of America

The Tissue Chip Program is comprised of several academic and government entities, aimed to bioengineer micro-physiological platforms (or chips) that mimic human organ systems.  These MPS platforms would be utilized for predicting efficacy and toxicity of candidate compounds faster, cheaper and with less use of animal models compared with current methods.  Now approaching the final year of the program, organ platform integration, rigorous testing and building public-private partnerships are the primary goals, setting the stage for future proposed initiatives including disease modeling.

16:30

Coffee Break and Networking

17:00

Panel Discussion Focusing on Challenges and Opportunities in the Organs-on-Chip Space Moderated by Roumteen Keshe, CN Bio Innovations Ltd.

18:00

Networking Cocktail Reception for All Delegates, Speakers, Sponsors and Exhibitors: Enjoy Beer, Wine, Appetizers and a View of the Charles River and Boston from the 15th Floor Conference Center

19:30

Close of Day 1 of the Conference

AGENDA for July 8, 2016

Friday, 8 July 2016

07:30

Morning Coffee, Breakfast Pastries, and Networking


Session Title: Deriving Value from Organs-on-Chips and 3D-Cultures

08:00

Raman Imaging and Beat Profiling of the Pharmacological Reaction of Neonatal Rat Cardiomyocytes in a Centrifugal Microfluidic Chip
Wilfred Espulgar, Research Fellow, Osaka University, Japan

Raman images and beat profiles of neonatal rat cardiomyocytes trapped in a centrifugal microfluidic chip applied for pharmacological reaction study.

08:30

Combining Microtissue Spheroids and Integrated Microfluidic Technology for Parallelized Micro-physiological Systems
Olivier Frey, Group leader, Eidgenössische Technische Hochschule (ETH) Zürich, Switzerland

The presentation will focus on recent developments and experimental results combining spherical microtissues with integrated microfluidic technology for creating microphysiological multi-tissue systems. I will highlight, why spheroids as a 3D cell culturing model are suitable for such application and how we implemented their integration into microfludic culturing systems for automated parallelized assays bearing high flexibility in application, robustness and usability. Further, the implementation of microsensors and pumps will be presented and discussed.

09:00

Inflammation on a Chip
Daniel Irimia, Associate Professor, Associate Director, BioMEMS Resource Center, Massachusetts General Hospital & Harvard Medical School, United States of America

09:30

Digital Magnetophoresis for Rare Cell Collection and their Logical Manipulation
Cheolgi Kim, Professor, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Korea South

The ability to manipulate individual cells has profound applications for gene sequencing, single cell analysis for their heterogeneity based on cell separation technology. Even though, various single cell platforms are exit, it is still challenge to collect rare cells and their digital manipulation in large-scale. Here, we demonstrate a class of integrated magnetic track circuits for executing sequential and parallel, timed operations on an ensemble of single particles and cells. The magnetic tracks are fabricated by lithographic technology. These magnetic tracks used for the passive control of cells/particles similar to electrical conductor, diodes and capacitor. When the magnetic tracks are combined into arrays and driven by rotating magnetic field, the single cells are precisely control for multiplexed analysis. In addition, the concentric cell translocation and separation were performed by the assembly of this magnetic track into a novel architecture, resembled with spider web network, where all the cells are concentrated into one position and then transported to apartments for the single cell analysis.

10:00

3D Printing in Biocompatible Polymers
Richard Gray, Regional Director, Dolomite Microfluidics, United Kingdom

3D printers must overcome two significant challenges to address applications in Life Science – first, being able to print using biocompatible FDA approved materials, and second, being able to print leak-proof microfluidic channels and structures. This presentation describes development of Dolomite’s Fluidic Factory, which can print fluidically sealed parts in COC in minutes. Key product technologies will be described, and examples of applications in life sciences will be given.

10:30

Coffee Break and Networking in the Exhibit Hall

11:00

James Hickman Keynote Presentation

Integration of Cells with Silicon Devices for the Development of Functional Organ-on-a-Chip Systems for Preclinical Drug Discovery and Toxicology
James Hickman, Professor, University of Central Florida, United States of America

One of the primary limitations in drug discovery and toxicology research is the lack of good model systems between the single cell level and animal or human systems. In addition, with the banning of animals for toxicology testing in the EU, the development of body-on-a-chip systems to replace animals with human mimics is essential for product development and safety testing. Our research focus is on the establishment of functional in vitro systems to address this deficit where we seek to create organ mimics and their subsystems to model motor control, muscle function, myelination and cognitive function, as well as cardiac conduction and force generation. The idea is to integrate microsystems fabrication technology and surface modifications with protein and cellular components, for initiating and maintaining self-assembly and growth into biologically, mechanically and electronically interactive functional multi-component systems in a circulating serum-free medium. Our philosophy is to start with 2D systems and only add complexity as needed to address biological questions to keep cost of the system at a minimum. We are using this ability to manipulate biological systems and integrate them with silicon-based systems to create body-on-a-chip systems for high content drug discovery. Examples will be given of some of the more advanced body-on-a-chip systems including a recent 4-organ system, neuromuscular junction system, and integrated cancer subsystems that are being developed as well as the results of five workshops held at NIH to explore what is needed for validation and qualification of these platforms.

11:30

Reyk Horland Keynote Presentation

Multi-Organ-Chip Developments: Towards a Paradigm Shift in Drug Development
Reyk Horland, Vice President, TissUse GmbH, Germany

Present in vitro and animal tests for drug development do not reliable predict the human outcomes of tested drugs or substances because they are failing to emulate the organ complexity of the human body, leading to high attrition rates in clinical studies. Here, Multi-Organ-Chips provide high potential for the in vitro combination of different cell types and organoids to realize a better understanding of their physiological in vivo crosstalk. The expectation is that such tests would predict, for example, toxicity, immunogenicity, ADME profiles and efficacy in vitro, reducing and replacing laboratory animal testing and streamlining human clinical trials. The ultimate aim for microphysiological systems in drug development is to recapitulate the various stages of a disease and even understand the stages before the disease is clinically manifested, which may open the way for new treatment paradigms. This talk will present examples of current Multi-Organ combinations and how the advanced knowledge and experience acquired will eventually enable the development of a Body-on-a-chip system. In addition, the question of how to qualify and validate these systems will be addressed.

12:00

Advanced Integrated Optical Oxygen and pH Sensors for Organ-on-Chip Applications
Torsten Mayr, Associate Professor, Leader-Applied Sensors, Graz University of Technology Austria, Austria

Integrated optical oxygen and pH sensors are presented enabling monitoring of oxygen content and pH changes in microfluidic cell cultures or organ on chips with a high precision read-out.

12:30

Enjoy Lunch on Your Own


Session Title: Emerging Technologies Session

13:30

Jennifer Lewis Keynote Presentation

Bioprinting 3D Tissues on Perfusable Chips
Jennifer Lewis, Hansjörg Wyss Professor, Harvard University, United States of America

The advancement of tissue and, ultimately, organ engineering requires the ability to pattern human tissues composed of cells, extracellular matrix, and vasculature with controlled microenvironments that can be sustained over prolonged time periods. To date, bioprinting methods have yielded thin tissues that only survive for short durations. To improve their physiological relevance, we report a method for bioprinting 3D tissues  on perfusable chips. Specifically, we will describe the bioprinting of thick vascularized, stem-cell laden tissues that can be controllably perfused and differentiated along an osteogenic lineage on chip. We will then describe how this approach can be extended to create other functional tissue constructs, such as 3D proximal tubules, on chip for drug screening. Our approach combines bioprinting, 3D cell culture, and tissue-on-chip concepts opening new avenues for drug screening, disease models, and ultimately tissue repair and regeneration.

14:00

Wei Sun Keynote Presentation

Bioprinting In vitro Tissue Models: Challenges and Opportunities
Wei Sun, National “Thousand-Talent” Distinguished Professor, Tsinghua University; Albert Soffa Chair Professor, Drexel University, China

3D Bio-Printing uses cells, biologics and/or biomaterials as building block to fabricate personalized 3D structures or functional in vitro biological models for regenerative medicine, disease study and drug discovery. This presentation will review some recent advances on 3D Bioprinting.  Applications of using bioprinting technology for fabrication of tissue engineering model, drug testing model and cancer tumor model will be given, along with discussions for challenges and opportunities in the field of Bio-3D Printing.

14:30

Reconstitution and Visualization of Tumors-on-Chip for Precision Medicine
Maria Carla Parrini, Senior Research Engineer, Institut Curie, France

Tumor microenvironments are ecosystems composed of a variety of cell types positioned in complex physicochemical contexts. We generated microfluidic devices in which highly-controlled cell co-cultures reconstituted a breast tumor ecosystem (Her2+ sub-type), containing cancer cells, cancer-associated fibroblasts, endothelial cells, and immune cells. We succeeded in recapitulating on these tumors-on-chip the immune-dependent systemic response to a drug used in clinic, the Trastuzumab monoclonal antibody (Herceptin®). This approach provides a novel experimental system to understand the complex effects of Trastuzumab on the tumor microenvironment and, very importantly, to investigate its resistance mechanisms. We are currently working toward the personalization of these tumors-on-chip by the introduction of patient-derived cells in the perspective of personalized diagnostic and precision medicine.

OOAC2016_600x176_3for2

SELECTBIO US is organizing its Second Annual Organ-on-a-Chip World Congress & 3D-Culture Conference, July 7-8, 2016, Boston. This conference draws upon the success of the inaugural conference and brings forth the latest technology trends and innovations in these two interconnected fields.

The Congress is composed of two concurrent, co-located tracks – agendas are live:

1. Organ-on-a-Chip and Body-on-a-Chip: In Vitro Systems Mimicking In Vivo Functions
2. Organs-on-Chips and 3D-Cultures: Technologies and Approaches

Registered Delegates Received Access to Both Tracks for Maximal Learning and Networking

Topics Addressed at this Congress

3D-Culture of Cells: Drivers and Approaches

3D-Microtissues

Body-on-a-Chip

 

– Artery-on-a-Chip for Cardiovascular Disease Research

 

– Bone-on-a-chip

 

– Brain/Neuron-on-a-Chip

 

– Disease-on-a-Chip/Cancer-on-a-Chip

 

– Gut-on-a-Chip

 

– Hematological Systems-on-a-Chip

 

– Immunotherapy on-a-Chip

 

– Liver-on-a-Chip for Drug Discovery/Toxicity Screening/Toxicology Studies

 

– Lung-on-a-Chip

 

– Medical Device-on-a-Chip

 

– Prostate-on-a-Chip

 

– Tumor-on-a-Chip

 

– Vagina-on-a-Chip

Microfluidics/Lab-on-a-Chip (LOAC) Technologies for Constructing Organ-on-a-Chip/Tissue-on-a-Chip/Body-on-a-Chip

Organoid Assembly

Sensor Integration-on-a-Chip

Technologies for Organ-on-a-Chip Biofabrication

Confirmed Keynote Speakers

David Hughes, Chief Technical Officer, CN Bio Innovations Ltd. LiverChip – Development of Organ-on-a-chip Liver Disease Models

George Truskey, R. Eugene and Susie E. Goodson Professor of Biomedical Engineering, Duke University Circulatory System and Integrated Muscle Tissue for Drug and Toxicity Testing

Geraldine A. Hamilton, President & Chief Scientific Officer, Emulate; Formerly the Lead Senior Staff Scientist, Wyss Institute for Biologically Inspired Engineering, Harvard University Organs-On-Chips for Advancing Drug Development and Personal Health

James Hickman, Professor, University of Central Florida Integrated Functional in vitro Systems for Toxicology and Drug Discovery Applications

Kristin Fabre, Scientific Program Manager, NIH National Center for Advancing Translational Science (NCATS) The NIH Tissue Chip Program: Current Progress and Future Initiatives

Linda Griffith, Professor of Biological and Mechanical Engineering, Massachusetts Institute of Technology (MIT) Move Over, Mice — How the Fusion of Systems Biology with Organs on Chips May Humanize Drug Development

Martin Yarmush, Director, Center for Engineering in Medicine, Massachusetts General Hospital (MGH) Organ-on-a-Chip Technologies: Advances and Challenges

Michael Shuler, Samuel B. Eckert Professor of Engineering, Cornell University Using Human “Body-on-a-Chip” Devices to Aid Drug Development

Nancy Allbritton, Professor and Chair, University of North Carolina Microengineered Systems for Recapitulating Intestinal Function

Olivier Guenat, Head, Organs-on-Chip Technologies, ARTORG Center for Biomedical Engineering Research, University of Bern-Switzerland Lung-on-Chip Models for Drug Discovery Applications

Paul Vulto, Managing Director, MIMETAS 96 Kidney Tubules On-a-Chip For Real-Time Toxicity Testing

Reyk Horland, Vice President, TissUse GmbH Multi-Organ-Chip Developments: Towards a Paradigm Shift in Drug Development

Roger Kamm, Professor, Massachusetts Institute of Technology (MIT) Creating Vascularized Tissue Constructs in Microfluidic Assays

Wei Sun, Professor, Tsinghua University and Albert Soffa Chair Professor of Mechanical Engineering, Drexel University Bioprinting In vitro Tissue Models: Challenges and Opportunities

Confirmed Speakers Include

Alexander Mosig, Lab Head, Biochip-based Organ Models, Jena University Hospital

Cheolgi Kim, Professor, Daegu Gyeongbuk Institute of Science and Technology (DGIST)

Daniel Irimia, Assistant Professor, Associate Director, BioMEMS Resource Center, Massachusetts General Hospital & Harvard Medical School

Hee-Gyeong Yi, Researcher, Pohang University of Science and Technology

Herman Blok, Business Development Manager, Micronit Microfluidics BV

Hiroshi Kimura, Associate Professor, Tokai University

Holger Becker, Chief Scientific Officer, Microfluidic ChipShop GmbH

Ioannis Zervantonakis, Research Fellow in Cell Biology, Harvard Medical School

John Wikswo, A.B. Learned Professor of Living State Physics; Founding Director, Vanderbilt Institute for Integrative Biosystems, Vanderbilt University

Jonathan Thon, Assistant Professor, Brigham and Women’s Hospital/Harvard Medical School, Co-Founder — Platelet BioGenesis

Kenneth Scott Phillips, Biofilms Research Group Leader, US FDA Center for Devices and Radiological Health

Martin Stelzle, Head of BioMEMS & Sensors Department, NMI at University of Tübingen

Matthew Hancock, Senior Engineer, Veryst Engineering, LLC

Michael Golway, President & CEO, Advanced Solutions, Inc.

Muhammad Ibrahim, Researcher, Institute of Biology, Leiden University

Murat Cirit, Director of Translational Systems Pharmacology, Massachusetts Institute of Technology (MIT)

Nathalie Picollet-D’Hahan, Senior Project Manager, Commissariat à l’Energie Atomique et aux Energies Alternatives (CEA) Grenoble

Noo Li Jeon, Professor, Seoul National University

Olivier Frey, Group leader, Eidgenössische Technische Hochschule (ETH) Zürich

Robert Esmond, Director, Sterne, Kessler, Goldstein & Fox P.L.L.C

Sahar Biglari, Researcher, University of Sydney

Thomas Corso, Chief Technical Officer, CorSolutions

Torsten Mayr, Associate Professor, Leader-Applied Sensors, Graz University of Technology Austria

Wilfred Espulgar, Research Fellow, Osaka University

William Whitford, Strategic Solutions Leader, GE Healthcare Life Sciences

Training Courses in Tandem with the Main Conference:

Organ-on-a-Chip: Technologies, Applications and Commercial Opportunities

Presented by Professor Mike Shuler, Cornell University and

Professor James Hickman, University of Central Florida

Designing and Validating Assays Applied to 3D-Cultures

Presented by Dr. Terry Riss, Global Strategic Marketing, Promega Corporation

3 Delegates for the Price of 2 Offer Active for this Conference

For more information or to register, please contact:

Jeff Fan

Events Manager

Select Biosciences, Inc.

Telephone: +1 510-857-4865

Jeff@selectbioconferences.com

SOURCE

From: Jeff Fan <j.fan@noreply.selectbio.com>

Reply-To: Jeff Fan <j.fan@noreply.selectbio.com>

Date: Tuesday, May 3, 2016 at 1:42 PM

To: Aviva Lev-Ari <AvivaLev-Ari@alum.berkeley.edu>

Subject: Organ-on-a-Chip World Congress and 3D-Culture, July 7-8, 2016, Boston. Network with All the Opinion Leaders in the Field

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Google Glass Meets Organs-on-Chips

 

Reported by: Irina Robu, PhD

Google Glass is a recently designed wearable device capable of displaying information in a smartphone-like hands-free format by wireless communication designed by Brigham and Women’s Hospital that mimic the human physiological system. The device allows researchers to test drug compounds and predict physiological responses with high acccuracy in laboratory setting.

The Glass also provides control over remote devices, primarily enabled by voice recognition commands and offers researchers a hands-free and flexible monitoring system. To make Google Glass work, Zhang et al. custom developed hardware and software that takes advantage of the voice control command in order to not only monitor but remotely control their liver and heart on chip systems. The Google Glass device is also capable in monitoring physical and physiological parameters such as temperature, pH and morphology of liver- and heart-on-chips.

The Google Glass has particular importance in cases where the experimental conditions threaten human life, as when researchers work with highly contagious bacteria and virus or radioactivity.
Source

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Medical MEMS, BioMEMS and Sensor Applications

Curator and Reporter: Aviva Lev-Ari, PhD, RN

 

Contents for Chapter 11

Medical MEMS, BioMEMS and Sensors Applications

Curators: Justin D. Pearlman, MD, PhD, FACC, LPBI Group, Danut Dragoi, PhD, LPBI Group and William H. Zurn, Alpha IP

FOR

Series E: Patient-centered Medicine

Volume 4:  Medical 3D BioPrinting – The Revolution in Medicine

Editors: Larry H Bernstein, MD FCAP and Aviva Lev-Ari, PhD, RN

https://pharmaceuticalintelligence.com/biomed-e-books/series-e-titles-in-the-strategic-plan-for-2014-1015/volume-four-medical-3d-bioprinting-the-revolution-in-medicine/

Work-in-Progress

ContactLens

Image Source

http://www.memsjournal.com/2010/05/medical-applications-herald-third-wave-of-mems.html

Image is courtesy of Google Images

 

WirelessPressure

Image Source

Stanford Engineering Team Invents Pressure Sensor That Uses Radio Waves | CytoFluidix

Image is courtesy of Google Images

 

Introduction by Dr. Pearlman

 

Chapter 1: Blood Glucose Sensors

1.1       MINIATURIZED GLUCOSE SENSOR – Google

  • Tiny wireless chip and miniaturized glucose sensor
  • Embedded between two layers of soft contact lens material
  • Accurate glucose monitoring for diabetics
  • Using bodily fluids, i.e. tears
  • Prototypes can generate one reading per second
  • Experimenting with LEDs
  • Early warning for the wearer

 

Chapter 2: Blood Chemistry Tests – up to 100 Samples

2.1       NON-INVASIVE BLOOD MONITOR- UCSD

  • Digital tattoo monitors blood below the skin
  • Tattoos are needle-less
    • Sensor-laden transdermal patch
  • Painless for the user Tiny sensors “ink”
  • Can read blood levels of:
    • Sodium, glucose, kidney function
  • Prototypes contain probes
  • Wireless, battery-powered chip
  • Continually test up to a hundred different samples

 

2.3       CELLPHONE-BASED RAPID-DIAGNOSTIC-TEST (RDT) READER – UCLA

  • Lateral flow immuno-chromatographic assays
  • Sense the presence of a target analyte in a sample
  • Device connects to the camera on a cell phone
  • Weighs only 65 grams

 

2.4       IMPLANTABLE BLOOD ANALYZER CHIP – EPFL

  • Implantable device for instantaneous blood analysis
  • Wireless data transmission to a doctor
  • Applications include monitoring general health
  • Tailor drug delivery to a patient’s unique needs
  • Includes five sensors and a radio transmitter
  • Powered via inductive coupling from a battery patch
  • Worn outside the body

 

Chapter 3: Motion Sensors for Head-Impact

3.1       HEAD-IMPACT MONITORING PATCH – STMicro & X2Biosystems

  • Wearable electronic contains MEMS motion sensors
  • Microcontroller, low-power radio transmitter, and power management circuitry
  • Cloud-based system combines athlete concussion history
  • Pre-season neurocognitive function, balance, and coordinate-performance data
  • Creates a baseline for comparison after a suspected injury event

 

Chapter 4: Drug Delivery & Drug Compliance Monitoring Systems

4.1       Smart Pill delivers Therapeutic Agent Load to target – ELECTRONIC PILL – Phillips

  • Electronic pill to treat gastrointestinal cancer
  • An ingestible pill is swallowed by the patient, finds its way to the tumor, dispenses the drugs and passes harmlessly from the body
  • Smart pill contains reservoir for drug supply, fluid pump for drug delivery, pH sensor (for navigation), thermometer, microprocessor, communication

 

4.2       Drug Compliance Monitoring Systems

4.2.1    INGESTIBLE BIOMEDICAL SENSOR – Proteus Digital Health

  • Biomedical sensor that monitors medication adherence
  • Embedded into a pill, the sensor is activated by stomach fluid
  • Transmits a signal through the body to a skin patch
  • Indicates whether a patient has ingested material

 

4.2.2    MICROPUMP DEVICES – Purdue University

  • Device based on skin contact actuation for drug delivery
  • Actuation mechanism only requires body heat
  • Induced actuation can result to a gradient of 100 Pa/oC
  • Sufficient to drive liquid drug through micro-needle arrays
  • Prototypes exhibit low fabrication costs, employment of biocompatible materials and battery-less operation Suitable for single- or multiple-use transdermal drug dispensers

 

4.2.3    IMPLANTABLE MEMS DRUG DELIVERY SYSTEM – MIT

  • Device can deliver a vasoconstrictor agent
  • On demand to injured soldiers to prevent hemorrhagic shock
  • Other applications include medical implants
  • For cancer detection and monitoring
  • Implant can provide physicians and patients
  • Real-time information on the efficacy of treatment

 

Chapter 5: Remove Monitoring of Food-related Diseases

5.1       LASER-DRIVEN, HANDHELD SPECTROMETER

  • For analyzing food scanned
  • Information to a cloud-based application
  • Examines the results Data is accumulated from many users
  • Used to develop warning algorithms
  • For Allergies, Bacteria

 

Chapter 6: Skin Protection and Photo-Sensitivity Management

6.1       WEARABLE-UVEXPOSURESENSOR – Gizmag

  • Wristband for monitoring UV exposure
  • Allows user to maximize vitamin D production
  • Reducing the risk of sun
  • Over-exposure and skin cancer
  • LED indicators light up as UV exposure accumulates
  • Flashes once the safe UV limit has been reached

 

6.2       WEARABLE SKIN SENSOR KTH – Chemistry 2011

  • Bio-patch for measuring and collecting vital information through the skin
  • Inexpensive, versatile and comfortable to wear
  • User Data being gathered depends on where it is placed on the body

 

Chapter 7: Ophthalmic Applications

7.1       INTRAOCULAR PRESSURE SENSOR – Sensimed & ST Microelectronics

  • Smart contact lens called Triggerfish
  • Contact lens can measure, monitor, and control
  • Intra-ocular pressure levels for patients
  • Catch early cases of glaucoma
  • MEMS strain gage pressure sensor
  • Mounted on a flexible substrate MEMS

 

7.2       MICRO-MIRRORS ENABLING HANDHELD OPHTHALMIC – OCT News

  • Swept source OCT model for retinal 3D imaging
  • Replaces bulky galvanometer scanners in a handheld OCT probe for primary care physicians
  • Ultrahigh-speed two-axis optical beam steering gimbal-less MEMS mirrors
  • MEMS Actuator with a 2.4 mm bonded mirror and an angular reach of +6°
  • Low power consumption of <100mW including the MEMS actuator driver Retinal 3D Imaging

 

Chapter 8: Hearing Assist Technologies

8.1       MEMS TECHNOLOGY FOR HEARING RESTORATION – University of Utah

  • Eliminates electronics outside the ear
  • Associated with reliability issues and social stigma
  • Accelerometer-based microphone
  • Successfully tested in cadaver ear canals
  • Prototype measures 2.5 x 6.2mm, weighs 25mg

 

Chapter 9: Lab-on-a-Chip

9.1       ORGAN-ON-A-CHIP – Johns Hopkins University

  • Silicon substrate for living human cells
  • Controlled environment
  • Emulate how cells function inside a living human body
  • Replace controversial and costly animal testing
  • Lab-on-a-chip: a cost effective end to animal testing

 

Chapter 10: Intra-Cranial Studies: Pressure Measurement, Monitoring and Adaptation

10.1:   CEREBRAL PRESSURE SENSOR – Fraunhofer Institute

  • Sensor to monitor cerebral pressure that can lead to dementia
  • Pressure changes in the brain can be measured and transmitted
  • Reading device outside the patient’s body
  • Operating at very low power, the sensor module
  • Powered wirelessly by the reading device

 

10.2    WIRELESS, IMPLANTABLE BRAIN SENSOR – National Institute of Biomedical Imaging and Bioengineering

  • Fully implantable within the brain
  • Allow natural studies of brain activity
  • Cord-free control of advanced prosthetics

Wireless charging Prototypes transmitted brain activity data

 

Chapter 11: Cardiac and Cardiovascular Monitoring System

11.1    IMPLANTABLE MICRO DEVICE FOR MONITORING AND TREATING ANEURISMS – Electronic Design

  • RF-addressed wireless pressure sensor are powered by inductive coupling
  • Do not need batteries MEMS pressure sensor
  • Wireless antenna are inserted near the heart
  • With a catheter, Blood-pressure readings
  • Are sent to a wireless scanner for monitoring Pressure changes
  • Deflect the transducer’s diaphragm
  • Change the LC circuit’s resonant

 

11.2    CUSTOM- FITTED, IMPLANTABLE DEVICE FOR TREATMENT AND PREDICTION OF CARDIAC DISORDERS – Washington University

  • Working prototypes were developed on inexpensive 3D printers
  • The 3D elastic membrane is made of a soft, flexible, silicon material
  • Precisely shaped to match the outer layer of the heart

 

Chapter 12: microfluidic chips

12.1    MICROFLUIDIC MEMS FOR DIABETES TREATMENT – Micronews

  • Watertight pump mounted on a disposable skin patch
  • Provides continuous insulin infusion
  • Controlled by a dedicated smart phone device
  • Incorporating a BGM (blood- glucose meter)

 

12.2    ACOUSTIC RECEIVER ANTENNA/SENSOR PDMS MEMBRANE – Purdue

POLY-DI-METHYL-SILOXANE (PDMS)

Polydimethylsiloxane called PDMS or dimethicone is a polymer widely used for the fabrication and prototyping of microfluidic chips.

It is a mineral-organic polymer (a structure containing carbon and silicon) of the siloxane family (word derived from silicon, oxygen and alkane). Apart from microfluidics, it is used as a food additive (E900), in shampoos, and as an anti-foaming agent in beverages or in lubricating oils.

For the fabrication of microfluidic devices, PDMS (liquid) mixed with a cross-linking agent is poured into a microstructured mold and heated to obtain a elastomeric replica of the mold (PDMS cross-linked).

 

Why Use PDMS for Microfluidic Device Fabrication?

 

PDMS was chosen to fabricate microfluidic chips primarily for those reasons:

Human alveolar epithelial and pulmonary microvascular endothelial cells cultured in a PDMS chip to mimick lung functions

  • It is transparent at optical frequencies (240 nM – 1100 nM), which facilitates the observation of contents in micro-channels visually or through a microscope.
  • It has a low autofluorescence [2]
  • It is considered as bio-compatible (with some restrictions).

The PDMS bonds tightly to glass or another PDMS layer with asimple plasma treatment. This allows the production of multilayers PDMS devices and enables to take advantage of technological possibilities offered by glass substrates, such as the use of metal deposition, oxide deposition or surface functionalisation.

PDMS, during cross-linking, can be coated with a controlled thickness on a substrate using a simple spincoat. This allows the fabrication of multilayer devices and the integration of micro valves.

It is deformable, which allows the integration of microfluidic valves using the deformation of PDMS micro-channels, the easy connection of leak-proof fluidic connections and its use to detect very low forces like biomechanics interactions from cells.

SOURCE

http://www.elveflow.com/microfluidic-tutorials/microfluidic-reviews-and-tutorials/the-poly-di-methyl-siloxane-pdms-and-microfluidics/

 

  • Ferrite RF radiation Acoustic wave Rectifier
  • Buried in PDMS Implantable miniature pressure sensor
  • Powered by an acoustically actuated cantilever
  • No battery required
  • Acoustic waves in the 200-500 hertz range
  • Cause cantilever to vibrate
  • Scavenging energy to power pressure sensor

 

Chapter 13: Peropheral Neuropathy Management

13.1    WIRELESS SHOE INSERT – Mobile Health News

  • WIRELESS SHOE INSERT – Mobile Health News
  • Help diabetics manage peripheral nerve damage
  • Insole collects data of where wearers
  • Putting pressure on their feet
  • Transmits wirelessly to a wristwatch-type display
  • Prevent amputations that often stem from diabetic foot ulcers

 

Chapter 14: Endoscopic Diagnostics Tools

14.1    ENDOSCOPE USING MEMS SCANNING MIRROR

  • For gastrointestinal and urological imaging
  • Alternative to biopsies in cancer detection
  • A laser beam pointed at the mirror is precisely deflected
  • Steered by the scanning mirror to reach a target

 

Chapter 15: MEMS guided Surgical Tools

15.1    MICROMACHINED SURGICAL TOOLS; SILICON MEMS TWEEZERS – ElectrolQ Used for minimally invasive surgical (MIS)

  • Procedures where diagnosis, monitoring, or treatment of diseases are performed
  • Performing with very small incisions MEMS
  • Based microsurgical tools is a key enabling technology for angioplasty, catheterization, endoscopy, laparoscopy, and neurosurgery

 

Summary by Dr. Pearlman

  • Multiple projects by Academia & Industry
  • Multiple MEMS devices for measuring body activities.
  • Many patch type devices attached to the skin
  • Devices attached to the eye
  • Smaller is better, lower footprint, lower power

 

 

 

 

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Contribution to Inflammatory Bowel Disease (IBD) of bacterial overgrowth in gut on a chip

Larry H. Bernstein, MD, FCAP, Curator

LPBI

 

Contributions of microbiome and mechanical deformation to intestinal bacterial overgrowth and inflammation in a 

human gut-on-a-chip 
Gut-On-a-Chip Holds Clues for Treating Inflammatory Bowel Diseases
Greg Watry
Human intestinal epithelial cells cultured in the Wyss Institute's human gut-on-a-chip form differentiated intestinal villi when cultured in the presence of lifelike fluid flow and rhythmic, peristalsis-like motions. Here the villi are visible using a traditional microscope (left) or a confocal microscope (right); when the same villi are stained with fluorescent antibodies, it clearly reveals the nuclei in the intestinal cells (blue) and their specialized apical membranes when they contact the intestinal lumen (green). Credit: Wyss Institute at Harvard University
Human intestinal epithelial cells cultured in the Wyss Institute’s human gut-on-a-chip form differentiated intestinal villi when cultured in the presence of lifelike fluid flow and rhythmic, peristalsis-like motions. Here the villi are visible using a traditional microscope (left) or a confocal microscope (right); when the same villi are stained with fluorescent antibodies, it clearly reveals the nuclei in the intestinal cells (blue) and their specialized apical membranes when they contact the intestinal lumen (green). Credit: Wyss Institute at Harvard University

Roughly the size of a computer memory stick and made of clear flexible polymer, the human gut-on-a-chip was created by Harvard Univ.’s Wyss Institute in 2012. Three years later, researchers are utilizing the technology in hopes of creating new therapies for inflammatory bowel diseases (IBD).

The Centers for Disease Control and Prevention estimates that between 1 and 1.3 million people suffer from IBD, including such diseases as ulcerative colitis and Crohn’s disease. With origins still mysterious, IBD is currently incurable.

“It has not been possible to study…human intestinal inflammatory diseases, because it is not possible to independently control these parameters in animal studies or in vitro models,” wrote the researchers in Proceedings of the National Academy of the Sciences. “In particular, given the recent recognition of the central role of the intestinal microbiome in human health and disease, including intestinal disorders, it is critical to incorporate commensal microbes into experimental models, however, this has not been possible using conventional culture systems.”

Additionally, static in vitro methods fail to replicate the pathophysiology of human IBD.

But the hollow-channeled microfluidic gut-on-a-chip successfully simulates the human intestine’s physical structure, microenvironment, peristalsis-like motion, and fluid flow.

“With our human gut-on-a-chip, we can not only culture the normal gut microbiome for extended times, but we can also analyze contributions of pathogens, immune cells, and vascular and lymphatic endothelium, as well as model specific diseases to understand the complex pathophysiological responses of the intestinal tract,” said Donald Ingber, founding director of the Wyss Institute.

The device was “used to co-culture multiple commensal microbes in contact with living human intestinal epithelial cells for more than a week in vitro and to analyze how gut microbiome, inflammatory cells, and peristalsis-associated mechanical deformations independently contribute to intestinal bacterial overgrowth and inflammation,” the researchers wrote.

Thus far, use of the device has yielded two interesting observations.

Four proteins—called cytokines—work together to trigger an inflammatory responses that exacerbate the bowel, the researchers found. Potentially, this new discovery could lead to the development of treatments that block the cytokine interaction.

Another observation, the researchers noted, is that “by ceasing peristalsis-like motions while maintaining luminal flow, lack of epithelial deformation was shown to trigger bacterial overgrowth similar to that observed in patients with ileus and inflammatory bowel disease,” according to the researchers.

The researchers believe the micro-device may one day be applicable to precision medicine. Eventually, a custom treatment may arise from scientists using a patient’s gut microbiota and cells on a human gut-on-a-chip.

 

 

Contributions of microbiome and mechanical deformation to intestinal bacterial overgrowth and inflammation in a human gut-on-a-chip
Hyun Jung Kima,1, Hu Lia,2, James J. Collinsa,b,c,d,e,f,3, and Donald E. Ingbera,g,h,
http://www.pnas.org/content/early/2015/12/09/1522193112.full.pdf

A human gut-on-a-chip microdevice was used to coculture multiple commensal microbes in contact with living human intestinal epithelial cells for more than a week in vitro and to analyze how gut microbiome, inflammatory cells, and peristalsis-associated mechanical deformations independently contribute to intestinal bacterial overgrowth and inflammation. This in vitro model replicated results from past animal and human studies, including demonstration that probiotic and antibiotic therapies can suppress villus injury induced by pathogenic bacteria. By ceasing peristalsis-like motions while maintaining luminal flow, lack of epithelial deformation was shown to trigger bacterial overgrowth similar to that observed in patients with ileus and inflammatory bowel disease. Analysis of intestinal inflammation on-chip revealed that immune cells and lipopolysaccharide endotoxin together stimulate epithelial cells to produce four proinflammatory cytokines (IL-8, IL-6, IL-1β, and TNF-α) that are necessary and sufficient to induce villus injury and compromise intestinal barrier function. Thus, this human gut-on-a-chip can be used to analyze contributions of microbiome to intestinal pathophysiology and dissect disease mechanisms in a controlled manner that is not possible using existing in vitro systems or animal models.

 

Significance The main advance of this study is the development of a microengineered model of human intestinal inflammation and bacterial overgrowth that permits analysis of individual contributors to the pathophysiology of intestinal diseases, such as ileus and inflammatory bowel disease, over a period of weeks in vitro. By studying living human intestinal epithelium, with or without vascular and lymphatic endothelium, immune cells, and mechanical deformation, as well as living microbiome and pathogenic microbes, we identified previously unknown contributions of specific cytokines, mechanical motions, and microbiome to intestinal inflammation, bacterial overgrowth, and control of barrier function. We provide proof-of-principle to show that the microfluidic gut-on-a-chip device can be used to create human intestinal disease models and gain new insights into gut pathophysiology.

 

Various types of inflammatory bowel disease (IBD), such as Crohn’s disease and ulcerative colitis, involve chronic inflammation of human intestine with mucosal injury and villus destruction (1), which is believed to be caused by complex interactions between gut microbiome (including commensal and pathogenic microbes) (2), intestinal mucosa, and immune components (3). Suppression of peristalsis also has been strongly associated with intestinal pathology, inflammation (4, 5), and small intestinal bacterial overgrowth (5, 6) in patients with Crohn’s disease (7) and ileus (8). However, it has not been possible to study the relative contributions of these different potential contributing factors to human intestinal inflammatory diseases, because it is not possible to independently control these parameters in animal studies or in vitro models. In particular, given the recent recognition of the central role of the intestinal microbiome in human health and disease, including intestinal disorders (2), it is critical to incorporate commensal microbes into experimental models; however, this has not been possible using conventional culture systems. Most models of human intestinal inflammatory diseases rely either on culturing an intestinal epithelial cell monolayer in static Transwell culture (9) or maintaining intact explanted human intestinal mucosa ex vivo (10) and then adding live microbes and immune cells to the apical (luminal) or basolateral (mucosal) sides of the cultures, respectively. These static in vitro methods, however, do not effectively recapitulate the pathophysiology of human IBD. For example, intestinal epithelial cells cultured in Transwell plates completely fail to undergo villus differentiation, produce mucus, or form the various specialized cell types of normal intestine. Although higher levels of intestinal differentiation can be obtained using recently developed 3D organoid cultures (11), it is not possible to expose these cells to physiological peristalsis-like motions or living microbiome in long-term culture, because bacterial overgrowth occurs rapidly (within ∼1 d) compromising the epithelium (12). This is a major limitation because establishment of stable symbiosis between the epithelium and resident gut microbiome as observed in the normal intestine is crucial for studying inflammatory disease initiation and progression (13), and rhythmical mechanical deformations driven by peristalsis are required to both maintain normal epithelial differentiation (14) and restrain microbial overgrowth in the intestine in vivo (15).

Thus, we set out to develop an experimental model that would overcome these limitations. To do this, we adapted a recently described human gut-on-a-chip microfluidic device that enables human intestinal epithelial cells (Caco-2) to be cultured in the presence of physiologically relevant luminal flow and peristalsislike mechanical deformations, which promotes formation of intestinal villi lined by all four epithelial cell lineages of the small intestine (absorptive, goblet, enteroendocrine, and Paneth) (12, 16). These villi also have enhanced barrier function, drug-metabolizing cytochrome P450 activity, and apical mucus secretion compared with the same cells grown in conventional Transwell cultures, which made it possible to coculture a probiotic gut microbe (Lactobacillus rhamnosus GG) in direct contact with the intestinal epithelium for more than 2 wk (12), in contrast to static Transwell cultures (17) or organoid cultures (11) that lose viability within hours under similar conditions. In the present study, we leveraged this human gut-on-a-chip to develop a disease model of small intestinal bacterial overgrowth (SIBO) and inflammation. We analyzed how probiotic and pathogenic bacteria, lipopolysaccharide (LPS), immune cells, inflammatory cytokines, vascular endothelial cells and mechanical forces contribute individually, and in combination, to intestinal inflammation, villus injury, and compromise of epithelial barrier function. We also explored whether we could replicate the protective effects of clinical probiotic and antibiotic therapies on-chip to demonstrate its potential use as an in vitro tool for drug development, as well as for dissecting fundamental disease mechanisms.

 

Fig. 1. The human gut-on-a-chip microfluidic device and changes in phenotype resulting from different culture conditions on-chip, as measured using genome-wide gene profiling. (A) A photograph of the device. Blue and red dyes fill the upper and lower microchannels, respectively. (B) A schematic of a 3D cross-section of the device showing how repeated suction to side channels (gray arrows) exerts peristalsis-like cyclic mechanical strain and fluid flow (white arrows) generates a shear stress in the perpendicular direction. (C) A DIC micrograph showing intestinal basal crypt (red arrow) and villi (white arrow) formed by human Caco-2 intestinal epithelial cells grown for ∼100 h in the gut-on-achip under medium flow (30 μL/h) and cyclic mechanical stretching (10%, 0.15 Hz). (Scale bar, 50 μm.) (D) A confocal immunofluorescence image showing a horizontal cross-section of intestinal villi similar to those shown in Fig. 1C, stained for F-actin (green) that labels the apical brush border of these polarized intestinal epithelial cells (nuclei in blue). (Scale bar, 50 μm.) (E) Hierarchical clustering analysis of genome-wide transcriptome profiles (Top) of Caco-2 cells cultured in the static Transwell, the gut-on-a-chip (with fluid flow at 30 μL/h and mechanical deformations at 10%, 0.15 Hz) (Gut Chip), or the mechanically active gut-on-a-chip cocultured with the VSL#3 formulation containing eight probiotic gut microbes (Gut Chip + VSL#3) for 72 h compared with normal human small intestinal tissues (Duodenum, Jejunum, and Ileum; microarray data from the published GEO database). The dendrogram was generated based on the averages calculated across all replicates, and all branches in the cluster have the approximately unbiased (AU) P value equal to 100. The y axis next to the dendrogram represents the metric for Euclidean distance between samples. Corresponding pseudocolored GEDI maps analyzing profiles of 650 metagenes between samples described above (Bottom).

 

Fig. 2. Reconstitution of pathological intestinal injury induced by interplay between nonpathogenic or pathogenic enteroinvasive E. coli bacteria or LPS endotoxin with immune cells. (A) DIC images showing that the normal villus morphology of the intestinal epithelium cultured on-chip (Control) is lost within 24 h after EIEC (serotype O124:NM) are added to the apical channel of the chip (+EIEC; red arrows indicate bacterial colonies). (B) Effects of GFP-EC, LPS (15 μg/mL), EIEC, or no addition (Control) on intestinal barrier function (Left). Right shows the TEER profiles in the presence of human PBMCs (+PBMC). GFP-EC, LPS, and EIEC were added to the apical channel (intestinal lumen) at 4, 12, and 35 h, respectively, and PBMCs were subsequently introduced through the lower capillary channel at 44 h after the onset of experiment (0 h) (n = 4). (C) Morphological analysis of intestinal villus damage in response to addition of GFP-EC, LPS, and EIEC in the absence (−PBMC) or the presence of immune components (+PBMC). Schematics (experimental setup), phase contrast images (horizontal view, taken at 57 h after onset), and fluorescence confocal micrographs (vertical cross-sectional views at 83 h after onset) were sequentially displayed. F-actin and nuclei were coded with magenta and blue, respectively. (D) Quantification of intestinal injury evaluated by measuring changes in lesion area (Top; n = 30) and the height of the villi (Bottom; n = 50) in the absence (white) or the presence (gray) of PBMCs. Intestinal villi were grown in the gut-on-a-chip under trickling flow (30 μL/h) with cyclic deformations (10%, 0.15 Hz) during the preculture period for ∼100 h before stimulation (0 h, onset). Asterisks indicate statistical significance compared with the control at the same time point (*P < 0.001, **P < 0.05). (Scale bars, 50 μm.)

 

Recapitulating Organ-Level Intestinal Inflammatory Responses. During inflammation in the intestine, pathophysiological recruitment of circulating immune cells is regulated via activation of the underlying vascular endothelium. To analyze this organ-level inflammatory response in our in vitro model, a monolayer of human microvascular endothelial cells (Fig. 3 C and D and Fig. S6 A and C) or lymphatic endothelial cells (Fig. S6 B and C) was cultured on the opposite (abluminal) side of the porous ECM-coated membrane in the lower microchannel of the device to effectively create a vascular channel (Fig. 3C). To induce intestinal inflammatory responses, LPS (Fig. 3 C and D) or TNF-α (Fig. S6) was flowed through the upper epithelial channel for 24 h, and then PBMCs were added to the vascular channel for 1 h without flow (Fig. 3 C and D). Treatment with both LPS (or TNF-α) and PBMCs resulted in the activation of intercellular adhesion molecule-1 (ICAM-1) expression on the surface of the endothelium (Fig. 3 C and D, Left, and Fig. S6) and a significant increase (P < 0.001) in the number of PBMCs that adhered to the surface of the capillary endothelium compared with controls (Fig. 3D). These results are consistent with our qPCR results, which also showed up-regulation of genes involved in immune cell trafficking (Fig. S5). Neither addition of LPS nor PBMCs alone was sufficient to induce ICAM-1 expression in these cells (Fig. 3D), which parallels the effects of LPS and PBMCs on epithelial production of inflammatory cytokines (Fig. 3A) as well as on villus injury (Fig. 2 B and D).

Evaluating Antiinflammatory Probiotic and Antibiotic Therapeutics On-Chip. To investigate how the gut microbiome modulates these inflammatory reactions, we cocultured the human intestinal villi with the eight strains of probiotic bacteria in the VSL#3 formulation that significantly enhanced intestinal differentiation (Fig. 1E and Fig. S1B). To mimic the in vivo situation, we colonized our microengineered gut on a chip with the commensal microbes (VSL#3) first and then subsequently added immune cells (PBMCs), pathogenic bacteria (EIEC), or both in combination. The VSL#3 microbial cells inoculated into the germ-free lumen of the epithelial channel primarily grew as discrete microcolonies in the spaces between adjacent villi (Fig. 4A and Movie S3) for more than a week in culture (Fig. S7A), and no planktonic growth was detected. These microbes did not overgrow like the EIEC (Fig. 2A and Movie S2), although occasional microcolonies also appeared at different spatial locations in association with the tips of the villi (Fig. S7 B and C). The presence of these living components of the normal gut microbiome significantly enhanced (P < 0.001) intestinal barrier function, producing more than a 50% increase in TEER relative to control cultures (Fig. 4B) without altering villus morphology (Fig. 4C). This result is consistent with clinical studies suggesting that probiotics, including VSL#3, can significantly enhance intestinal barrier function in vivo (18).

To mimic the effects of antibiotic therapies that are sometimes used clinically in patients with intestinal inflammatory disease (29), we identified a dose and combination of antibiotics (100 units per mL penicillin and 100 μg/mL streptomycin) that produced effective killing of both EIEC and VSL#3 microbes in liquid cultures (Fig. S9) and then injected this drug mixture into the epithelial channel of guton-a-chip devices infected with EIEC. When we added PBMCs to these devices 1 h later, intestinal barrier function (Fig. 4B) and villus morphology (Fig. 4C) were largely protected from injury, and there was a significant reduction in lesion area (Fig. 4D). Thus, the gut-on-a-chip was able to mimic suppression of injury responses previously observed clinically using other antibiotics that produce similar bactericidal effects.

Analyzing Mechanical Contributions to Bacterial Overgrowth. Finally, we used the gut-on-a-chip to analyze whether physical changes in peristalsis or villus motility contribute to intestinal pathologies, such as the small intestinal bacterial overgrowth (SIBO) (5, 6) observed in patients with ileus (8) and IBD (7). When the GFPEC bacteria were cultured on the villus epithelium under normal flow (30 μL/h), but in the absence of the physiological cyclic mechanical deformations, the number of colonized bacteria was significantly higher (P < 0.001) compared with gut chips that experienced mechanical deformations (Fig. 5A). Bacterial cell densities more than doubled within 21 h when cultured under conditions without cyclic stretching compared with gut chips that experienced physiological peristalsis-like mechanical motions, even though luminal flow was maintained constant (Fig. 5B). Thus, cessation of epithelial distortion appears to be sufficient to trigger bacterial overgrowth, and motility-induced luminal fluid flow is not the causative factor as assumed previously (7).

 

Discussion One of the critical prerequisites for mimicking the living human intestine in vitro is to establish a stable ecosystem containing physiologically differentiated intestinal epithelium, gut bacteria, and immune cells that can be cultured for many days to weeks. Here we leveraged a mechanically active gut-on-a-chip microfluidic device to develop an in vitro model of human intestinal inflammation that permits stable long-term coculture of commensal microbes of the gut microbiome with intestinal epithelial cells. The synthetic model of the human living intestine we built recapitulated the minimal set of structures and functions necessary to mimic key features of human intestinal pathophysiology during chronic inflammation and bacterial overgrowth including epithelial and vascular inflammatory processes and destruction of intestinal villi.

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Current Advances in Medical Technology

Larry H. Bernstein, MD, FCAP, Curator

LPBI

Pumpkin-Shaped Molecule Enables 100-Fold Improved MRI Contrast

Tue, 10/13/2015 – 9:16amby Forschungsverbund Berlin e.V. (FVB)

http://www.mdtmag.com/news/2015/10/pumpkin-shaped-molecule-enables-100-fold-improved-mri-contrast

Assuming that we could visualize pathological processes such as cancer at a very early stage and additionally distinguish the various different cell types, this would represent a giant step for personalized medicine. Xenon magnetic resonance imaging has the potential to fulfil this promise – if suitable contrast media are found that react sensitively enough to the “exposure”. Researchers at the Leibniz-Institut für Molekulare Pharmakologie in Berlin have now found that a class of pumpkin-shaped molecules called cucurbiturils together with the inert gas xenon, enables particularly good image contrast – namely around 100 times better than has been possible up to now. This finding published in the November issue cover article of Chemical Science by the Royal Society of Chemistry points the way to the tailoring of new contrast agents to different cell types and has the potential to enable molecular diagnostics even without tissue samples in the future.

Personalized medicine instead of one treatment for all – especially in cancer medicine, this approach has led to a paradigm shift. Molecular diagnostics is the key that will give patients access to tailor-made therapy. However, if tumors are located in poorly accessible areas of the body or several tumor foci are already present, this often fails due to a lack of sufficient sensitivity of the diagnostic imaging. But such sensitivity is needed to determine the different cell types, which differ considerably even within a tumor. Although even the smallest of tumor foci and other pathological changes can be detected using the PET-CT, a differentiation according to cell type is usually not possible.

Scientists from the FMP are therefore focusing on xenon magnetic resonance imaging: The further development of standard magnetic resonance imaging makes use of the “illuminating power” of the inert gas xenon, which can provide a 10,000-fold enhanced signal in the MRI. To do this, it must be temporarily captured by so-called “cage molecules” in the diseased tissue. This has been more or less successful with the molecules used to date, but the experimental approach is still far from a medical application.

Cucurbituril Provides Stunning Image Contrasts
The research group led by Dr. Leif Schröder at the Leibniz-Institut für Molekulare Pharmakologie (FMP) has now discovered a molecule class for this purpose that eclipses all of the molecules used to date. Cucurbituril exchanges around 100 times more xenon per unit of time than its fellow molecules, which leads to a much better image contrast. “It very quickly became clear that cucurbituril might be suitable as a contrast medium,” reports Leif Schröder. “However, it was surprising that areas marked with it were imaged with a much better contrast than previously.” The explanation is to be found in the speed. Upon exposure, so to speak, cucurbituril generates contrast more rapidly than all molecules used to date, as it only binds the xenon very briefly and thus transmits the radio waves to detect the inert gas to very many xenon atoms within a fraction of a second. In this way, the inert gas is passed through the molecule much more efficiently.

In the study, which appeared in the specialist journal “Chemical Science”, the world’s first MRI images with cucurbituril have been achieved. With the aid of a powerful laser and a vaporized alkali metal, the researchers initially greatly strengthened the magnetic properties of normal xenon. The hyperpolarized gas was then introduced into a test solution with the cage molecules. A subsequent MRI image showed the distribution of the xenon in the object. In a second image, the curcurbituril together with radio waves destroyed the magnetization of the xenon, leading to dark spots on the images.

“Comparison of the two images demonstrates that only the xenon in the cages has the right resonance frequency to produce a dark area,” explains Schröder. “This blackening is possible to a much better degree with cucurbituril than with previous cage molecules, for it works like a very light-sensitive photographic paper. The contrast is around 100 times stronger.”

Time-of-Flight IC Revolutionizes Object Detection and Distance Measurement

Tue, 10/13/2015 – 9:07amby Intersil

New ISL29501 signal processing IC detects objects up to two meters

http://www.mdtmag.com/product-release/2015/10/time-flight-ic-revolutionizes-object-detection-and-distance-measurement
Intersil Corporation has introduced an innovative time-of-flight (ToF) signal processing IC that provides a complete object detection and distance measurement solution when combined with an external emitter (LED or laser) and photodiode. The ISL29501 ToF device offers one-of-a-kind functionality, including ultra-small size, low-power consumption and superior performance ideal for connected devices that make up the Internet of Things (IoT), as well as consumer mobile devices and the emerging commercial drone market.

The ISL29501 overcomes the shortcomings of traditional amplitude-based proximity sensors and other ToF solutions that perform poorly in lighting conditions above 2,000 lux, or cannot provide distance information unless the object is perpendicular to the sensor.

The ISL29501 applies Intersil’s power management expertise to save power and extend battery life through several innovations.

“Prior to Intersil’s time-of-flight technology breakthrough, there was no practical way to measure distance up to two meters in a small form factor,” said Andrew Cowell, senior vice president of Mobile Power Products at Intersil. “The innovative ISL29501 provides customers a cost-effective, small footprint solution that also gives them the flexibility to use multiple devices to increase the field of view to a full 360 degrees for enhanced object detection capabilities.”

Key Features and Specifications

  • On-chip DSP calculates ToF for accurate proximity detection and distance measurement up to two meters
  • Modulation frequency of 4.5MHz prevents interference with other consumer products such as IR TV remote controls that operate at 40kHzOn-chip emitter DAC with programmable current up to 255mA
  • Allows designers to choose the desired current level to optimize distance measurement and power budget
  • Operates in single shot mode for initial object detection and approximate distance measurement, while continuous mode improve distance accuracy
  • On-chip active ambient light rejection minimizes or eliminates the influence of ambient light during distance measurement
  • Programmable distance zones: allows the user to define three ToF distance zones for determining interrupt alerts
  • Interrupt controller generates interrupt alerts using distance measurements and user defined thresholds
  • Automatic gain control sets optimum analog signal levels to achieve best SNR response
  • Supply voltage range of 2.7V to 3.3V
  • I2C interface supports 1.8V and 3.3V bus

The ISL29501 can be combined with the ISL9120 buck-boost regulator to further reduce power consumption and extend battery life in consumer and home automation applications.

Optoelectronic Implantable Could Enable Two-Way Communication with Brain

Mon, 10/12/2015 – 4:04pmby Brown University

http://www.mdtmag.com/news/2015/10/optoelectronic-implantable-could-enable-two-way-communication-brain

Brown University researchers have created a new type of optoelectronic implantable device to access brain microcircuits, synergizing a technique that enables scientists to control the activity of brains cells using pulses of light. The invention, described in the journal Nature Methods, is a cortical microprobe that can stimulate multiple neuronal targets optically by specific patterns on micrometer scale while simultaneously recording the effects of that stimulation in the underlying neural microcircuits of interest with millisecond precision.

“We think this is a window-opener,” said Joonhee Lee, a senior research associate in Professor Arto Nurmikko’s lab in the School of Engineering at Brown and one of the lead authors of the new paper. “The ability to rapidly perturb neural circuits according specific spatial patterns and at the same time reconstruct how the circuits involved are perturbed, is in our view a substantial advance.”

First introduced around 2005, optogenetics has enriched ability of scientists seeking to understand brain function at the neuronal level. The technique involves genetically engineering neurons to express light-sensitive proteins on their membranes. With those proteins expressed, pulses of light can be used to either promote or suppress activity in those particular cells. The method gives researchers in principle unprecedented ability to control specific brain cells at specific times.

But until now, simultaneous optogenetic stimulation and recording of brain activity rapidly across multiple points within a brain microcircuit of interest has proven difficult. Doing it requires a device that can both generate a spatial pattern of light pulses and detect the dynamical patterns of electrical reverberations generated by excited cellular activity. Previous attempts to do this involved devices that cobbled together separate components for light emission and electrical sensing. Such probes were physically bulky, not ideal for insertion into a brain. And because the emitters and the sensors were necessarily a hundreds of micrometers apart, a sizable distance, the link between stimulation and recorded signal was ambiguous.

The new compact, integrated device developed by Nurmikko’s lab begins with the unique advantages endowed by a so-called wide bandgap semiconductor called zinc oxide. It is optically transparent yet able readily to conduct an electrical current.

“Very few materials have that pair of physical properties,” Lee said. “The combination makes it possible to both stimulate and detect with the same material.”

Joonhee Lee, with Assistant Research Professor Ilker Ozden and Professor Yoon-Kyu Song at Seoul National University in Korea, co-developed a novel microfabrication method with Nurmikko to shape the material into a monolithic chip just a few millimeters square with sixteen micrometer sized pin-like “optoelectrodes,” each capable of both delivering light pulses and sensing electrical current. The array of optoelectrodes enables the device to couple to neural microcircuits composed of many neurons rather than single neurons.

Such ability to stimulate and record at the network level on spatial and time scales at which they operate is key, Nurmikko says. Brain functions are driven by neural circuits rather than single neurons.

“For example, when I move my hand, that’s an example of action driven by specific network-level activity in the brain,” he said. “Our new device approach gives scientists and engineers a tool in applying the full power of optogenetics as a means of neural stimulation, while providing the means to read activity of perturbed networks at multiple points at high spatial precision and time resolution.”

Ozden led the initial testing of the device in rodent models. The researchers looked at the extent to which different light intensities could stimulate network activity. The tests showed that increasing optical power led to distinct recruitment of neuronal circuits revealing functional connectivity in the targeted network.

“We went over a range of optical power that was large–over three orders of magnitude–and in so doing we got a range of network-related responses, in particular we could replicate an activity pattern naturally occurring in the brain.” Ozden said. “It gave us a new insight into how optogenetics operates on the network level. This gives us encouragement to go ahead and extend the repertoire and application of the device technology.”

Nurmikko’s group together with the Song lab in Seoul plan to continue further development of the device, ultimately include an access via wireless means. Their next steps anticipate the use of the new device technology as chronic implant in non-human primates at potentially hundreds of points and, depending on progress in worldwide research on optogenetics ahead, perhaps even one day in humans.

“At least, the initial building blocks are here,” Nurmikko said, who conceived the idea with his Korean colleague Song.

Study Advances Possibility of Mind-Controlled Devices

Mon, 10/12/2015 – 10:50amby Ryan Bushey, Associate Editor, R&D

A study published in the journal Nature Medicine has shown a possible path to creating effective neural prosthetics.

http://www.mdtmag.com/blog/2015/10/study-advances-possibility-mind-controlled-devices

The study’s subjects, only listed as T6 and T7, have Amyotropic Lateral Sclerosis (ALS). The scientists performed surgery on them one year ago to place a “neural recording device” in the part of the brain in charge of controlling hand function, notes Bloomberg.

The test documented in the study required T6 and T7 to perform a variety of tasks, such as moving a cursor to hit different targets on a computer screen. The device receives electrical impulses from the brain and morphs them into a computer signal to operate the cursor.

Both test subjects had the highest published performance so far, and even doubled the results of the previous clinical trial participant, according to the study.

The hope is that these devices can improve quality of life for people suffering from paralysis.

You can watch how T6 performed in her test below.

https://youtu.be/9P-qsiIORVU

Removing 62 Barriers to Pig–to–Human Organ Transplant in One Fell Swoop

Mon, 10/12/2015 – 9:09amby Wyss Institute for Biologically Inspired Engineering

The largest number of simultaneous gene edits ever accomplished in the genome could help bridge the gap between organ transplant scarcity and the countless patients who need them

http://www.mdtmag.com/news/2015/10/removing-62-barriers-pig%E2%80%93%E2%80%93human-organ-transplant-one-fell-swoop

Never before have scientists been able to make scores of simultaneous genetic edits to an organism’s genome. But now in a landmark study by George Church, Ph.D., and his team at the Wyss Institute for Biologically Inspired Engineering at Harvard University and Harvard Medical School, the gene editing system known as “CRISPR–Cas9” has been used to genetically engineer pig DNA in 62 locations – an explosive leap forward in CRISPR’s capability when compared to its previous record maximum of just six simultaneous edits. The 62 edits were executed by the team to inactivate retroviruses found natively in the pig genome that have so far inhibited pig organs from being suitable for transplant in human patients. With the retroviruses safely removed via genetic engineering, however, the road is now open toward the possibility that humans could one day receive life–saving organ transplants from pigs.

Church is a Wyss Core Faculty member, the Robert Winthrop Professor of Genetics at Harvard Medical School (HMS) and Professor of Health Sciences and Technology at Harvard and MIT. The advance, reported by Church and his team including the study’s lead author Luhan Yang, Ph.D., a Postdoctoral Fellow at HMS and the Wyss Institute, was published in the October 11 issue of Science.

The concept of xenotransplantation, which is the transplant of an organ from one species to another, is nothing new. Researchers and clinicians have long hoped that one of the major challenges facing patients suffering from organ failure – which is the lack of available organs in the United States and worldwide – could be alleviated through the availability of suitable animal organs for transplant. Pigs in particular have been especially promising candidates due to their similar size and physiology to humans. In fact, pig heart valves are already commonly sterilized and de–cellularized for use repairing or replacing human heart valves.

This artistic rendering shows pig chromosomes (background) which reside in the nucleus of pig cells and contain a single strand of RNA, and the Cas9 protein targeting DNA (foreground). The CRISPR–Cas9 gene editing system works like molecular scissors to precisely edit genes of interest. A new advance reported in Science by Wyss Core Faculty member George Church and his team used Cas9 to make 62 edits to the pig genome to remove latent retroviruses, presenting a solution to one of the largest safety concerns that has so far blocked progress in making pig organs compatible for xenotransplant in humans. (Credit: Wyss Institute at Harvard University)

But the transplant of whole, functional organs comprised of living cells and tissue constructs has presented a unique set of challenges for scientists. One of the primary problems has been the fact that most mammals including pigs contain repetitive, latent retrovirus fragments in their genomes – present in all their living cells – that are harmless to their native hosts but can cause disease in other species.

“The presence of this type of virus found in pigs – known as porcine endogenous retroviruses or PERVs – brought over a billion of dollars of pharmaceutical industry investments into developing xenotransplant methods to a standstill by the early 2000s,” said Church. “PERVs and the lack of ability to remove them from pig DNA was a real showstopper on what had been a promising stage set for xenotransplantation.”

Now – using CRISPR–Cas9 like a pair of molecular scissors – Church and his team have inactivated all 62 repetitive genes containing a PERV in pig DNA, surpassing a significant obstacle on the path to bringing xenotransplantation to clinical reality. With more than 120,000 patients currently in the United States awaiting transplant and less than 30,000 transplants on average occurring annually, xenotransplantation could give patients and clinicians an alternative in the future.

“Pig kidneys can already function experimentally for months in baboons, but concern about the potential risks of PERVs has posed a problem for the field of xenotransplantation for many years,” said David H. Sachs, M.D., Director of the TBRC Laboratories at Massachusetts General Hospital, Paul S. Russell Professor of Surgery Emeritus at Harvard Medical School, and Professor of Surgical Sciences at Columbia University’s Center for Translational Immunology. Sachs has been developing special pigs for xenotransplantation for more than 30 years and is currently collaborating with Church on further genetic modifications of his pigs. “If Church and his team are able to produce pigs from genetically engineered embryos lacking PERVs by the use of CRISPR-Cas9, they would eliminate an important potential safety concern facing this field.”

Yang says the team hopes eventually they can completely eliminate the risk that PERVs could cause disease in clinical xenotransplantation by using modified pig cells to clone a line of pigs that would have their PERV genes inactivated.

“This advance overcomes a major hurdle that has until now halted the progress of xenotransplantation research and development,” said Wyss Institute Founding Director Donald Ingber, M.D., Ph.D., who is also the Judah Folkman Professor of Vascular Biology at Harvard Medical School and Professor of Bioengineering at the Harvard John A. Paulson School of Engineering and Applied Sciences. “The real value and potential impact is in the number of lives that could be saved if we can one day use xenotransplants to close the huge gap between the number of available functional organs and the number of people who desperately need them.”

The remarkable and newly demonstrated capability for CRISPR to edit tens of repetitive genes such as PERVs will also unlock new ways for scientists to study and understand repetitive regions in the genome, which has been estimated to comprise more than two–thirds of our own human genome.

Contributors to the work also included: co–lead authors Marc Güell of the Wyss Institute and Harvard Medical School Department of Genetics, Dong Niu of HMS Dept. of Genetics and Zhejiang University’s College of Animal Sciences, and Haydy George of HMS Dept. of Genetics; and co–authors Emal Lesha, Dennis Grishin, Jürgen Poci, Ellen Shrock, and Rebeca Cortazio of HMS Dept. of Genetics, Weihong Xu of Massachusetts General Hospital Department of Surgery, and Robert Wilkinson and Jay Fishman of MGH’s Transplant Infection Disease & Compromised Host Program.

Novel Gut-on-a-Chip Nearly Indistinguishable from Human GI Tract

Fri, 10/09/2015 – 1:17pmby University of North Carolina Healthcare

http://www.mdtmag.com/news/2015/10/novel-gut-chip-nearly-indistinguishable-human-gi-tract?et_cid=4876632&et_rid=535648082

A team of researchers from the University of North Carolina at Chapel Hill and NC State University has received a $5.3 million, five-year Transformative Research (R01) Award from the National Institutes of Health (NIH) to create fully functioning versions of the human gut that fit on a chip the size of a dime.

Such “organs-on-a-chip” have become vital for biomedical research, as researchers seek alternatives to animal models for drug discovery and testing. The new grant will fund a technology that represents a major step forward for the field, overcoming limitations that have mired other efforts.

The technology will use primary cells derived directly from human biopsies, which are known to provide more relevant results than the immortalized cell lines used in current approaches. In addition, the device will sculpt these cells into the sophisticated architecture of the gut, rather than the disorganized ball of cells that are created in other miniature organ systems.

This is a picture of a schematic of colonic epithelial tissue. Crypt units are pointed down, flat surface faces center of the gut tube. Stem cells are red, progenitor cells are pink, differentiated cells are grey, blue and green. Yellow cells are stem cell niche cells. Lumenal surface is above crypts. (Credit: Scott Magness, PhD, UNC School of Medicine)

“We are building a device that goes far beyond the organ-on-a-chip,” said Nancy L. Allbritton, MD, PhD, professor and chair of the UNC-NC State joint department of biomedical engineering and one of four principle investigators on the NIH grant. “We call it a ‘simulacrum,’ a term used in science fiction to describe a duplicate. The idea is to create something that is indistinguishable from your own gut.”

Allbritton is an expert at microfabrication and microengineering. Also on the team are intestinal stem cell expert Scott T. Magness, PhD, associate professor of medicine, biomedical engineering, and cell and molecular physiology in the UNC School of Medicine; microbiome expert Scott Bultman, PhD, associate professor of genetics in the UNC School of Medicine; and bioinformatics expert Shawn Gomez, associate professor of biomedical engineering at UNC-Chapel Hill and NC State.

The impetus for the “organ-on-chip” movement comes largely from the failings of the pharmaceutical industry. For just a single drug to go through the discovery, testing, and approval process can take as many as 15 years and as much as $5 billion dollars. Animal models are expensive to work with and often don’t respond to drugs and diseases the same way humans do. Human cells grown in flat sheets on Petri dishes are also a poor proxy. Three-dimensional “organoids” are an improvement, but these hollow balls are made of a mishmash of cells that doesn’t accurately mimic the structure and function of the real organ.

Basically, the human gut is a 30-foot long hollow tube made up of a continuous single-layer of specialized cells. Regenerative stem cells reside deep inside millions of small pits or “crypts” along the tube, and mature differentiated cells are linked to the pits and live further out toward the surface. The gut also contains trillions of microbes, which are estimated to outnumber human cells by ten to one. These diverse microbial communities — collectively known as the microbiota — process toxins and pharmaceuticals, stimulate immunity, and even release hormones to impact behavior.

These are fluorescent images of the side view of two synthetic crypts. Blue: nuclei of the cells. Red: proliferating stem cells in similar location to those in the human colon. (Credit: Scott Magness, PhD, UNC School of Medicine)

To create a dime-sized version of this complex microenvironment, the UNC-NC State team borrowed fabrication technologies from the electronics and microfluidics world. The device is composed of a polymer base containing an array of imprinted or shaped “hydrogels,” a mesh of molecules that can absorb water like a sponge. These hydrogels are specifically engineered to provide the structural support and biochemical cues for growing cells from the gut. Plugged into the device will be various kinds of plumbing that bring in chemicals, fluids, and gases to provide cues that tell the cells how and where to differentiate and grow. For example, the researchers will engineer a steep oxygen gradient into the device that will enable oxygen-loving human cells and anaerobic microbes to coexist in close proximity.

“The underlying concept — to simply grow a piece of human tissue in a dish — doesn’t seem that groundbreaking,” said Magness. “We have been doing that for a long time with cancer cells, but those efforts do not replicate human physiology. Using native stem cells from the small intestine or colon, we can now develop gut tissue layers in a dish that contains stem cells and all the differentiated cells of the gut. That is the thing stem cell biologists and engineers have been shooting for, to make real tissue behave properly in a dish to create better models for drug screening and cell-based therapies. With this work, we made a big leap toward that goal.”

Right now, the team has a working prototype that can physically and chemically guide mouse intestinal stem cells into the appropriate structure and function of the gut. For several years, Magness has been isolating and banking human stem cells from samples from patients undergoing routine colonoscopies at UNC Hospitals. As part of the grant, he will work with the rest of the team to apply these stem cells to the new device and create “simulacra” that are representative of each patient’s individual gut. The approach will enable researchers to explore in a personalized way how both the human and microbial cells of the gut behave during healthy and diseased states.

“Having a system like this will advance microbiota research tremendously,” said Bultman. “Right now microbiota studies involve taking samples, doing sequencing, and then compiling an inventory of all the microbes in the disease cases and healthy controls. These studies just draw associations, so it is difficult to glean cause and effect. This device will enable us to probe the microbiota, and gain a better understanding of whether changes in these microbial communities are the cause or the consequence of disease.”

On-Chip Optical Sensing Technique Detects Multiple Flu Strains

Tue, 10/06/2015 – 10:11amby University of California – Santa Cruz

http://www.mdtmag.com/news/2015/10/chip-optical-sensing-technique-detects-multiple-flu-strains?et_cid=4876632&et_rid=535648082

A schematic view shows the optical waveguide intersecting a fluidic microchannel containing target particles. Targets are optically excited as they flow past well-defined excitation spots created by multi-mode interference; fluorescence is collected by the liquid-core waveguide channel and routed into solid-core waveguides (red). (Credit: Ozcelik et al., PNAS 2015)

New chip-based optical sensing technologies developed by researchers at UC Santa Cruz and Brigham Young University enable the rapid detection and identification of multiple biomarkers. In a paper published October 5 in Proceedings of the National Academy of Sciences, researchers describe a novel method to perform diagnostic assays for multiple strains of flu virus on a small, dedicated chip.

“A standard flu test checks for about ten different flu strains, so it’s important to have an assay that can look at ten to 15 things at once. We showed a completely new way to do that on an optofluidic chip,” said senior author Holger Schmidt, the Kapany Professor of Optoelectronics in the Baskin School of Engineering at UC Santa Cruz.

Over the past decade, Schmidt and his collaborators at BYU have developed chip-based technology to optically detect single molecules without the need for high-end laboratory equipment. Diagnostic instruments based on their optofluidic chips could provide a rapid, low-cost, and portable option for identifying specific disease-related molecules or virus particles.

In the new study, Schmidt demonstrated a novel application of a principle called wavelength division multiplexing, which is widely used in fiber-optic communications. By superimposing multiple wavelengths of light in an optical waveguide on a chip, he was able to create wavelength-dependent spot patterns in an intersecting fluidic channel. Virus particles labeled with fluorescent markers give distinctive signals as they pass through the fluidic channel depending on which wavelength of light the markers absorb.

“Each color of light produces a different spot pattern in the channel, so if the virus particle is labeled to respond to blue light, for example, it will light up nine times as it goes through the channel, if it’s labeled for red it lights up seven times, and so on,” Schmidt explained.

The researchers tested the device using three different influenza subtypes labeled with different fluorescent markers. Initially, each strain of the virus was labeled with a single dye color, and three wavelengths of light were used to detect them in a mixed sample. In a second test, one strain was labeled with a combination of the colors used to label the other two strains. Again, the detector could distinguish among the viruses based on the distinctive signals from each combination of markers. This combinatorial approach is important because it increases the number of different targets that can be detected with a given number of wavelengths of light.

For these tests, each viral subtype was separately labeled with fluorescent dye. For an actual diagnostic assay, fluorescently labeled antibodies could be used to selectively attach distinctive fluorescent markers to different strains of the flu virus.

While previous studies have shown the sensitivity of Schmidt’s optofluidic chips for detection of single molecules or particles, the demonstration of multiplexing adds another important feature for on-chip bioanalysis. Compact instruments based on the chip could provide a versatile tool for diagnostic assays targeting a variety of biological particles and molecular markers.

The optofluidic chip was fabricated by Schmidt’s collaborators at Brigham Young University led by Aaron Hawkins. The joint first authors of the PNAS paper are Damla Ozcelik and Joshua Parks, both graduate students in Schmidt’s lab at UC Santa Cruz. Other coauthors include Hong Cai and Joseph Parks at UC Santa Cruz and Thomas Wall and Matthew Stott at BYU.

In another recent paper, published September 25 in Nature Scientific Reports, Schmidt’s team reported the development of a hybrid device that integrates an optofluidic chip for virus detection with a microfluidic chip for sample preparation.

“These two papers represent important milestones for us. Our goal has always been to use this technology to analyze clinically relevant samples, and now we are doing it,” Schmidt said.

Boom in Gene-Editing Studies amid Ethics Debate over Its Use

Mon, 10/12/2015 – 1:54pmby Lauran Neergaard, AP Medical Writer

http://www.mdtmag.com/news/2015/10/boom-gene-editing-studies-amid-ethics-debate-over-its-use-0

The hottest tool in biology has scientists using words like revolutionary as they describe the long-term potential: wiping out certain mosquitoes that carry malaria, treating genetic diseases like sickle cell, preventing babies from inheriting a life-threatening disorder.

It may sound like sci-fi, but research into genome editing is booming. So is a debate about its boundaries, what’s safe and what’s ethical to try in the quest to fight disease.

Does the promise warrant experimenting with human embryos? Researchers in China already have, and they’re poised to in Britain.

Should we change people’s genes in a way that passes traits to future generations? Beyond medicine, what about the environmental effects if, say, altered mosquitoes escape before we know how to use them?

“We need to try to get the balance right,” said Jennifer Doudna, a biochemist at the University of California, Berkeley. She helped develop new gene-editing technology and hears from desperate families, but urges caution in how it’s eventually used in people.

The U.S. National Academies of Science, Engineering and Medicine will bring international scientists, ethicists and regulators together in December to start determining that balance. The biggest debate is whether it ever will be appropriate to alter human heredity by editing an embryo’s genes.

“This isn’t a conversation on a cloud,” but something that families battling devastating rare diseases may want, Dr. George Daley of Boston Children’s Hospital told specialists meeting this week to plan the ethics summit. “There will be a drive to move this forward.”

Laboratories worldwide are embracing a technology to precisely edit genes inside living cells — turning them off or on, repairing or modifying them — like a biological version of cut-and-paste software. Researchers are building stronger immune cells, fighting muscular dystrophy in mice and growing human-like organs in pigs for possible transplant. Biotech companies have raised millions to develop therapies for sickle cell disease and other disorders.

The technique has a wonky name — CRISPR-Cas9 — and a humble beginning.

Doudna was studying how bacteria recognize and disable viral invaders, using a protein she calls “a genetic scalpel” to slice DNA. That system turned out to be programmable, she reported in 2012, letting scientists target virtually any gene in many species using a tailored CRISPR recipe.

There are older methods to edit genes, including one that led to an experimental treatment for the AIDS virus, but the CRISPR technique is faster and cheaper and allows altering of multiple genes simultaneously.

“It’s transforming almost every aspect of biology right now,” said National Institutes of Health genomics specialist Shawn Burgess.

In this photo provided by UC Berkeley Public Affairs, taken June 20, 2014 Jennifer Doudna, right, and her lab manager, Kai Hong, work in her laboratory in Berkeley, Calif. The hottest tool in biology has scientists using words like revolutionary as they describe the long-term potential: wiping out certain mosquitoes that carry malaria, treating genetic diseases like sickle-cell, preventing babies from inheriting a life-threatening disorder. “We need to try to get the balance right,” said Doudna. She helped develop new gene-editing technology and hears from desperate families, but urges caution in how it’s eventually used in people. (Cailey Cotner/UC Berkeley via AP)

CRISPR’s biggest use has nothing to do with human embryos. Scientists are engineering animals with human-like disorders more easily than ever before, to learn to fix genes gone awry and test potential drugs.

Engineering rodents to harbor autism-related genes once took a year. It takes weeks with CRISPR, said bioengineer Feng Zhang of the Broad Institute at MIT and Harvard, who also helped develop and patented the CRISPR technique. (Doudna’s university is challenging the patent.)

A peek inside an NIH lab shows how it works. Researchers inject a CRISPR-guided molecule into microscopic mouse embryos, to cause a gene mutation that a doctor suspects of causing a patient’s mysterious disorder. The embryos will be implanted into female mice that wake up from the procedure in warm blankets to a treat of fresh oranges. How the resulting mouse babies fare will help determine the gene defect’s role.

Experts predict the first attempt to treat people will be for blood-related diseases such as sickle cell, caused by a single gene defect that’s easy to reach. The idea is to use CRISPR in a way similar to a bone marrow transplant, but to correct someone’s own blood-producing cells rather than implanting donated ones.

“It’s like a race. Will the research provide a cure while we’re still alive?” asked Robert Rosen of Chicago, who has one of a group of rare bone marrow abnormalities that can lead to leukemia or other life-threatening conditions. He co-founded the MPN Research Foundation, which has begun funding some CRISPR-related studies.

So why the controversy? CRISPR made headlines last spring when Chinese scientists reported the first-known attempt to edit human embryos, working with unusable fertility clinic leftovers. They aimed to correct a deadly disease-causing gene but it worked in only a few embryos and others developed unintended mutations, raising fears of fixing one disease only to cause another.

If ever deemed safe enough to try in pregnancy, that type of gene change could be passed on to later generations. Then there are questions about designer babies, altered for other reasons than preventing disease.

In the U.S., the NIH has said it won’t fund such research in human embryos.

In Britain, regulators are considering researchers’ request to gene-edit human embryos — in lab dishes only — for a very different reason, to study early development.

Medicine aside, another issue is environmental: altering insects or plants in a way that ensures they pass genetic changes through wild populations as they reproduce. These engineered “gene drives” are in very early stage research, too, but one day might be used to eliminate invasive plants, make it harder for mosquitoes to carry malaria or even spread a defect that gradually kills off the main malaria-carrying species, said Kevin Esvelt of Harvard’s Wyss Institute for Biologically Inspired Engineering.

No one knows how that might also affect habitats, Esvelt said. His team is calling for the public to weigh in and for scientists to take special precautions. For example, Esvelt said colleagues are researching a tropical mosquito species unlikely to survive cold Boston even if one escaped locked labs.

“There is no societal precedent whatsoever for a widely accessible and inexpensive technology capable of altering the shared environment,” Esvelt told a recent National Academy of Sciences hearing.

Researchers Use ‘Avatar’ Experiments to Get Leg Up On Locomotion

Mon, 10/12/2015 – 5:09pmby North Carolina State University

North Carolina State University scientists take a giant leap closer to understanding locomotion from the leg up

http://www.mdtmag.com/news/2015/10/researchers-use-avatar-experiments-get-leg-locomotion

Simple mechanical descriptions of the way people and animals walk, run, jump and hop liken whole leg behavior to a spring or pogo stick.

But until now, no one has mapped the body’s complex physiology – which in locomotion includes multiple leg muscle-tendons crossing the hip, knee and ankle joints, the weight of a body, and control signals from the brain – with the rather simple physics of spring-like limb behavior.

Using an “Avatar”-like bio-robotic motor system that integrates a real muscle and tendon along with a computer controlled nerve stimulator acting as the avatar’s spinal cord, North Carolina State University researchers have taken a giant leap closer to understanding locomotion from the leg up. The findings could help create robotic devices that begin to merge human and machine in order to assist human locomotion.

Despite the complicated physiology involved, NC State biomedical engineer Greg Sawicki and Temple University post-doctoral researcher Ben Robertson show that if you know the mass, the stiffness and the leverage of the ankle’s primary muscle-tendon unit, you can predict neural control strategies that will result in spring-like behavior.

“We tried to build locomotion from the bottom up by starting with a single muscle-tendon unit, the basic power source for locomotion in all things that move,” said Greg Sawicki, associate professor in the NC State and UNC-Chapel Hill Joint Department of Biomedical Engineering and co-author of a paper published in Proceedings of the National Academy of Sciences that describes the work. “We connected that muscle-tendon unit to a motor inside a custom robotic interface designed to simulate what the muscle-tendon unit ‘feels’ inside the leg, and then electrically stimulated the muscle to get contractions going on the benchtop.”

The researchers showed that resonance tuning is a likely mechanism behind springy leg behavior during locomotion. That is, the electrical system – in this case the body’s nervous system – drives the mechanical system – the leg’s muscle-tendon unit – at a frequency which provides maximum ‘bang for the buck’ in terms of efficient power output.

Sawicki likened resonance tuning to interacting with a slinky toy. “When you get it oscillating well, you hardly have to move your hand – it’s the timing of the interaction forces that matters.

“In locomotion, resonance comes from tuning the interaction between the nervous system and the leg so they work together,” Sawicki said. “It turns out that if I know the mass, leverage and stiffness of a muscle-tendon unit, I can tell you exactly how often I should stimulate it to get resonance in the form of spring-like, elastic behavior.”

The findings have design implications relevant to designing exoskeletons for able-bodied individuals, as well as exoskeleton or prosthetic systems for people with mobility impairments.

“In the end, we found that the same simple underlying principles that govern resonance in simple mechanical systems also apply to these extraordinarily complicated physiological systems,” said Robertson, the corresponding author of the paper.

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