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Archive for the ‘Organ-on-a-Chip & 3D Printing in Life Sciences’ Category


3D Liver Model in a Droplet

Curator: Marzan Khan, BSc

Recently, a Harvard University Professor of Physics and Applied Physics, David Weitz and his team of researchers have successfully generated 3D models of liver tissue composed of two different kinds of liver cells, precisely compartmentalized in a core-shell droplet, using the microfluidics approach(1). Compared to alternative in-vitro methods, this approach comes with more advantages – it is cost-effective, can be quickly assembled and produces millions of organ droplets in a second(1). It is the first “organ in a droplet” technology that enables two disparate liver cells to physically co-exist and exchange biochemical information, thus making it a good mimic of the organ in vivo(1).

Liver tissue models are used by researchers to investigate the effect of drugs and other chemical compounds, either alone or in combination on liver toxicity(2). The liver is the primary center of drug metabolism, detoxification and removal and all of these processes need to be carried out systematically in order to maintain a homeostatic environment within the body(2) Any deviation from the steady state will shift the dynamic equilibrium of metabolism, leading to production of reactive oxygen species (ROS)(2). These are harmful because they will exert oxidative stress on the liver, and ultimately cause the organ to malfunction. Drug-induced liver toxicity is a critical problem – 10% of all cases of acute hepatitis, 5% of all hospital admissions, and 50% of all acute liver failures are caused by it(2).

Before any novel drug is launched into the market, it is tested in-vitro, in animal models, and then progresses onto human clinical trials(1). Weitz’s system can produce up to one-thousand organ droplets per second, each of which can be used in an experiment to test for drug toxicity(1). Clarifying further, he asserts that “Each droplet is like a mini experiment. Normally, if we are running experiments, say in test tubes, we need a milliliter of fluid per test tube. If we were to do a million experiments, we would need a thousand liters of fluid. That’s the equivalent of a thousand milk jugs! Here, each droplet is only a nanoliter, so we can do the whole experiment with one milliliter of fluid, meaning we can do a million more experiments with the same amount of fluid.”

Testing hepatocytes alone on a petri dish is a poor indicator of liver-specific functions because the liver is made up of multiple cells systematically arranged on an extracellular matrix and functionally interdependent(3). The primary hepatocytes, hepatic stellate cells, Kupffer cells, endothelial cells and fibroblasts form the basic components of a functioning liver(3). Weitz’s upgraded system contains hepatocytes (that make up the majority of liver cells and carry out most of the important functions) supported by a network of fibroblasts(3). His microfluidic chip is comprised of a network of constricted, circular channels spanning the micrometer range, the inner phase of which contains hepatocytes mixed in a cell culture solution(3). The surrounding middle phase accommodates fibroblasts in an alginate solution and the two liquids remain separated due to differences in their chemical properties as well as the physics of fluids travelling in narrow channels. Addition of a fluorinated carbon oil interferes with the two aqueous layers, forcing them to become individual monodisperse droplets(3). The hydrogel shell is completed when a 0.15% solution of acetic acid facilitates the cross-linking of alginate to form a gelatinous shell, locking the fibroblasts in place(3). Thus, the aqueous core of hepatocytes are encapsulated by fibroblasts confined to a strong hydrogel network, creating a core-shell hydrogel scaffold of 3D liver micro-tissue in a droplet(3). Using empirical analysis, scientists have shown that albumin secretion and urea synthesis (two important markers of liver function) were significantly higher in a co-culture of hepatocytes and fibroblasts 3D core-shell spheroids compared to a monotypic cell-culture of hepatocyte-only spheroids(3). These results validate the theory that homotypic as well as heterotypic communication between cells are important to achieve optimal organ function in vitro(3).

This system of creating micro-tissues in a droplet with enhanced properties is a step-forward in biomedical science(3). It can be used in experiments to test for a myriad of drugs, chemicals and cosmetics on different human tissue samples, as well as to understand the biological connectivity of contrasting cells(3).

diagram

Image source: DOI: 10.1039/c6lc00231

A simple demonstration of the microfluidic chip that combines different solutions to create a core-shell droplet consisting of two different kinds of liver cells.

References:

  1. National Institute of Biomedical Imaging and Bioengineering. (2016, December 13). New device creates 3D livers in a droplet.ScienceDaily. Retrieved February 9, 2017 from https://www.sciencedaily.com/releases/2016/12/161213112337.htm
  2. Singh, D., Cho, W. C., & Upadhyay, G. (2015). Drug-Induced Liver Toxicity and Prevention by Herbal Antioxidants: An Overview.Frontiers in Physiology,6, 363. http://doi.org/10.3389/fphys.2015.00363
  3. Qiushui Chen, Stefanie Utech, Dong Chen, Radivoje Prodanovic, Jin-Ming Lin and David A. Weitz; Controlled assembly of heterotypic cells in a core– shell scaffold: organ in a droplet; Lab Chip, 2016, 16, 1346; DOI: 10.1039/c6lc00231

Other related articles on 3D on a Chip published in this Open Access Online Scientific Journal include the following:

 

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

Reporter: Aviva Lev-Ari, PhD, RN

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

Medical MEMS, BioMEMS and Sensor Applications

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

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

Larry H. Bernstein, MD, FCAP, Curator

Current Advances in Medical Technology

Larry H. Bernstein, MD, FCAP, Curator

 

Other related articles on Liver published in this Open Access Online Scientific Journal include the following:

 

Alnylam down as it halts development for RNAi liver disease candidate

by Stacy Lawrence

LIVE 9/21 8AM to 2:40PM Targeting Cardio-Metabolic Diseases: A focus on Liver Fibrosis and NASH Targets at CHI’s 14th Discovery On Target, 9/19 – 9/22/2016, Westin Boston Waterfront, Boston

Reporter: Aviva Lev-Ari, PhD, RN

2016 Nobel in Economics for Work on The Theory of Contracts to winners: Oliver Hart and Bengt Holmstrom

Reporter: Aviva Lev-Ari, PhD, RN

LIVE 9/20 2PM to 5:30PM New Viruses for Therapeutic Gene Delivery at CHI’s 14th Discovery On Target, 9/19 – 9/22/2016, Westin Boston Waterfront, Boston

Reporter: Aviva Lev-Ari, PhD, RN

Seven Cancers: oropharynx, larynx, oesophagus, liver, colon, rectum and breast are caused by Alcohol Consumption

Reporter: Aviva Lev-Ari, PhD, RN

 

Other related articles on 3D on a Chip published in this Open Access Online Scientific Journal include the following:

 

Liquid Biopsy Chip detects an array of metastatic cancer cell markers in blood – R&D @Worcester Polytechnic Institute,  Micro and Nanotechnology Lab

Reporters: Tilda Barliya, PhD and Aviva Lev-Ari, PhD, RN

Trovagene’s ctDNA Liquid Biopsy urine and blood tests to be used in Monitoring and Early Detection of Pancreatic Cancer

Reporters: David Orchard-Webb, PhD and Aviva Lev-Ari, PhD, RN

Liquid Biopsy Assay May Predict Drug Resistance

Curator: Larry H. Bernstein, MD, FCAP

One blood sample can be tested for a comprehensive array of cancer cell biomarkers: R&D at WPI

Curator: Marzan Khan, B.Sc

Real Time Coverage of the AGENDA for Powering Precision Health (PPH) with Science, 9/26/2016, Cambridge Marriott Hotel, Cambridge, MA

Reporter: Aviva Lev-Ari, PhD, RN

 

 

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BioPrinting Basics

Curator: Larry H. Bernstein, MD, FCAP

 

 

The ABCs of 3D Bioprinting of Living Tissues, Organs   5/06/2016 

(Credit: Ozbolat Lab/Penn State University)
(Credit: Ozbolat Lab/Penn State University)

Although first originated in 2003, the world of bioprinting is still very new and ambiguous. Nevertheless, as the need for organ donation continues to increase worldwide, and organ and tissue shortages prevail, a handful of scientists have started utilizing this cutting-edge science and technology for various areas of regenerative medicine to possibly fill that organ-shortage void.

Among these scientists is Ibrahim Tarik Ozbolat, an associate professor of Engineering Science and Mechanics Department and the Huck Institutes of the Life Sciences at Penn State University, who’s been studying bioprinting and tissue engineering for years.

While Ozbolat is not the first to originate 3D bioprinting research, he’s the first one at Penn State University to spearhead the studies at Ozbolat Lab, Leading Bioprinting Research.

“Tissue engineering is a big need. Regenerative medicine, biofabrication of tissues and organs that can replace the damage or diseases is important,” Ozbolat told R&D Magazine after his seminar presentation at Interphex last week in New York City, titled 3D Bioprinting of Living Tissues & Organs.”

3D bioprinting is the process of creating cell patterns in a confined space using 3D-printing technologies, where cell function and viability are preserved within the printed construct.

Recent progress has allowed 3D printing of biocompatible materials, cells and supporting components into complex 3D functional living tissues. The technology is being applied to regenerative medicine to address the need for tissues and organs suitable for transplantation. Compared with non-biological printing, 3D bioprinting involves additional complexities, such as the choice of materials, cell types, growth and differentiation factors, and technical challenges related to the sensitivities of living cells and the construction of tissues. Addressing these complexities requires the integration of technologies from the fields of engineering, biomaterials science, cell biology, physics and medicine, according to nature.com.

“If we’re able to make organs on demand, that will be highly beneficial to society,” said Ozbolat. “We have the capability to pattern cells, locate them and then make the same thing that exists in the body.”

3D bioprinting of tissues and organs

Sean V Murphy & Anthony Atala
Nature Biotechnology 32,773–785(2014)       doi:10.1038/nbt.2958

 

Additive manufacturing, otherwise known as three-dimensional (3D) printing, is driving major innovations in many areas, such as engineering, manufacturing, art, education and medicine. Recent advances have enabled 3D printing of biocompatible materials, cells and supporting components into complex 3D functional living tissues. 3D bioprinting is being applied to regenerative medicine to address the need for tissues and organs suitable for transplantation. Compared with non-biological printing, 3D bioprinting involves additional complexities, such as the choice of materials, cell types, growth and differentiation factors, and technical challenges related to the sensitivities of living cells and the construction of tissues. Addressing these complexities requires the integration of technologies from the fields of engineering, biomaterials science, cell biology, physics and medicine. 3D bioprinting has already been used for the generation and transplantation of several tissues, including multilayered skin, bone, vascular grafts, tracheal splints, heart tissue and cartilaginous structures. Other applications include developing high-throughput 3D-bioprinted tissue models for research, drug discovery and toxicology.

 

Future Technologies : Bioprinting
Bioprinting

3D printing is increasingly permitting the direct digital manufacture (DDM) of a wide variety of plastic and metal items. While this in itself may trigger a manufacturing revolution, far more startling is the recent development of bioprinters. These artificially construct living tissue by outputting layer-upon-layer of living cells. Currently all bioprinters are experimental. However, in the future, bioprinters could revolutionize medical practice as yet another element of the New Industrial Convergence.

Bioprinters may be constructed in various configurations. However, all bioprinters output cells from a bioprint head that moves left and right, back and forth, and up and down, in order to place the cells exactly where required. Over a period of several hours, this permits an organic object to be built up in a great many very thin layers.

In addition to outputting cells, most bioprinters also output a dissolvable gel to support and protect cells during printing. A possible design for a future bioprinter appears below and in the sidebar, here shown in the final stages of printing out a replacement human heart. Note that you can access larger bioprinter images on the Future Visions page. You may also like to watch my bioprinting video.

bioprinter

 

Bioprinting Pioneers

Several experimental bioprinters have already been built. For example, in 2002 Professor Makoto Nakamura realized that the droplets of ink in a standard inkjet printer are about the same size as human cells. He therefore decided to adapt the technology, and by 2008 had created a working bioprinter that can print out biotubing similar to a blood vessel. In time, Professor Nakamura hopes to be able to print entire replacement human organs ready for transplant. You can learn more about this groundbreaking work here or read this message from Professor Nakamura. The movie below shows in real-time the biofabrication of a section of biotubing using his modified inkjet technology.

 

Another bioprinting pioneer is Organovo. This company was set up by a research group lead by Professor Gabor Forgacs from the University of Missouri, and in March 2008 managed to bioprint functional blood vessels and cardiac tissue using cells obtained from a chicken. Their work relied on a prototype bioprinter with three print heads. The first two of these output cardiac and endothelial cells, while the third dispensed a collagen scaffold — now termed ‘bio-paper’ — to support the cells during printing.

Since 2008, Organovo has worked with a company called Invetech to create a commercial bioprinter called the NovoGen MMX. This is loaded with bioink spheroids that each contain an aggregate of tens of thousands of cells. To create its output, the NovoGen first lays down a single layer of a water-based bio-paper made from collagen, gelatin or other hydrogels. Bioink spheroids are then injected into this water-based material. As illustrated below, more layers are subsequently added to build up the final object. Amazingly, Nature then takes over and the bioink spheroids slowly fuse together. As this occurs, the biopaper dissolves away or is otherwise removed, thereby leaving a final bioprinted body part or tissue.

 

bioprinting stages

As Organovo have demonstrated, using their bioink printing process it is not necessary to print all of the details of an organ with a bioprinter, as once the relevant cells are placed in roughly the right place Nature completes the job. This point is powerfully illustrated by the fact that the cells contained in a bioink spheroid are capable of rearranging themselves after printing. For example, experimental blood vessels have been bioprinted using bioink spheroids comprised of an aggregate mix of endothelial, smooth muscle and fibroblast cells. Once placed in position by the bioprint head, and with no technological intervention, the endothelial cells migrate to the inside of the bioprinted blood vessel, the smooth muscle cells move to the middle, and the fibroblasts migrate to the outside.

In more complex bioprinted materials, intricate capillaries and other internal structures also naturally form after printing has taken place. The process may sound almost magical. However, as Professor Forgacs explains, it is no different to the cells in an embryo knowing how to configure into complicated organs. Nature has been evolving this amazing capability for millions of years. Once in the right places, appropriate cell types somehow just know what to do.

In December 2010, Organovo create the first blood vessels to be bioprinted using cells cultured from a single person. The company has also successfully implanted bioprinted nerve grafts into rats, and anticipates human trials of bioprinted tissues by 2015. However, it also expects that the first commercial application of its bioprinters will be to produce simple human tissue structures for toxicology tests. These will enable medical researchers to test drugs on bioprinted models of the liver and other organs, thereby reducing the need for animal tests.

In time, and once human trials are complete, Organovo hopes that its bioprinters will be used to produce blood vessel grafts for use in heart bypass surgery. The intention is then to develop a wider range of tissue-on-demand and organs-on-demand technologies. To this end, researchers are now working on tiny mechanical devices that can artificially exercise and hence strengthen bioprinted muscle tissue before it is implanted into a patient.

Organovo anticipates that its first artificial human organ will be a kidney. This is because, in functional terms, kidneys are one of the more straight-forward parts of the body. The first bioprinted kidney may in fact not even need to look just like its natural counterpart or duplicate all of its features. Rather, it will simply have to be capable of cleaning waste products from the blood. You can read more about the work of Organovoand Professor Forgac’s in this article from Nature.

Regenerative Scaffolds and Bones

A further research team with the long-term goal of producing human organs-on-demand has created the Envisiontec Bioplotter. Like Organovo’s NovoGen MMX, this outputs bio-ink ’tissue spheroids’ and supportive scaffold materials including fibrin and collagen hydrogels. But in addition, the Envisontech can also print a wider range of biomaterials. These include biodegradable polymers and ceramics that may be used to support and help form artificial organs, and which may even be used as bioprinting substitutes for bone.

Talking of bone, a team lead by Jeremy Mao at the Tissue Engineering and Regenerative Medicine Lab at Columbia University is working on the application of bioprinting in dental and bone repairs. Already, a bioprinted, mesh-like 3D scaffold in the shape of an incisor has been implanted into the jaw bone of a rat. This featured tiny, interconnecting microchannels that contained ‘stem cell-recruiting substances’. In just nine weeks after implantation, these triggered the growth of fresh periodontal ligaments and newly formed alveolar bone. In time, this research may enable people to be fitted with living, bioprinted teeth, or else scaffolds that will cause the body to grow new teeth all by itself. You can read more about this development in this article from The Engineer.

In another experient, Mao’s team implanted bioprinted scaffolds in the place of the hip bones of several rabbits. Again these were infused with growth factors. As reported inThe Lancet, over a four month period the rabbits all grew new and fully-functional joints around the mesh. Some even began to walk and otherwise place weight on their new joints only a few weeks after surgery. Sometime next decade, human patients may therefore be fitted with bioprinted scaffolds that will trigger the grown of replacement hip and other bones. In a similar development, a team from Washington State University have also recently reported on four years of work using 3D printers to create a bone-like material that may in the future be used to repair injuries to human bones.

In Situ Bioprinting

The aforementioned research progress will in time permit organs to be bioprinted in a lab from a culture of a patient’s own cells. Such developments could therefore spark a medical revolution. Nevertheless, others are already trying to go further by developing techniques that will enable cells to be printed directly onto or into the human body in situ. Sometime next decade, doctors may therefore be able to scan wounds and spray on layers of cells to very rapidly heal them.

Already a team of bioprinting researchers lead by Anthony Alata at the Wake Forrest School of Medicine have developed a skin printer. In initial experiments they have taken 3D scans of test injuries inflicted on some mice and have used the data to control a bioprint head that has sprayed skin cells, a coagulant and collagen onto the wounds. The results are also very promising, with the wounds healing in just two or three weeks compared to about five or six weeks in a control group. Funding for the skin-printing project is coming in part from the US military who are keen to develop in situ bioprinting to help heal wounds on the battlefield. At present the work is still in a pre-clinical phase with Alata progressing his research usig pigs. However, trials of with human burn victims could be a little as five years away.

The potential to use bioprinters to repair our bodies in situ is pretty mind blowing. In perhaps no more than a few decades it may be possible for robotic surgical arms tipped with bioprint heads to enter the body, repair damage at the cellular level, and then also repair their point of entry on their way out. Patients would still need to rest and recuperate for a few days as bioprinted materials fully fused into mature living tissue. However, most patients could potentially recover from very major surgery in less than a week.

Cosmetic Applications …

Bioprinting Implications …

More information on bioprinting can be found in my books 3D Printing: Second Editionand The Next Big Thing. There is also a bioprinting section in my 3D Printing Directory. Oh, and there is also a great infographic about bioprinting here. Enjoy!

 

How to print out a blood vessel

New work moves closer to the age of organs on demand.

Blood vessels can now be ‘printed out’ by machine. Could bigger structures be in the future?SUSUMU NISHINAGA / SCIENCE PHOTO LIBRARY

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Brain Biobank and studies of disease structure correlates

Larry H. Bernstein, MD, FCAP, Curator

LPBI

 

Unveiling Psychiatric Diseases

Researchers create neuropsychiatric cellular biobank

Image: iStock/mstroz
Image: iStock/mstroz
Researchers from Harvard Medical School and Massachusetts General Hospital have completed the first stage of an important collaboration aimed at understanding the intricate variables of neuropsychiatric disease—something that currently eludes clinicians and scientists.

The research team, led by Isaac Kohane at HMS and Roy Perlis at Mass General, has created a neuropsychiatric cellular biobank—one of the largest in the world.

It contains induced pluripotent stem cells, or iPSCs, derived from skin cells taken from 100 people with neuropsychiatric diseases such as schizophrenia, bipolar disorder and major depression, and from 50 people without neuropsychiatric illness.

In addition, a detailed profile of each patient, obtained from hours of in-person assessment as well as from electronic medical records, is matched to each cell sample.

As a result, the scientific community can now for the first time access cells representing a broad swath of neuropsychiatric illness. This enables researchers to correlate molecular data with clinical information in areas such as variability of drug reactions between patients. The ultimate goal is to help treat, with greater precision, conditions that often elude effective management.

The cell collection and generation was led by investigators at Mass General, who in collaboration with Kohane and his team are working to characterize the cell lines at a molecular level. The cell repository, funded by the National Institutes of Health, is housed at Rutgers University.

“This biobank, in its current form, is only the beginning,” said Perlis, director of the MGH Psychiatry Center for Experimental Drugs and Diagnostics and HMS associate professor of psychiatry. “By next year we’ll have cells from a total of four hundred patients, with additional clinical detail and additional cell types that we will share with investigators.”

A current major limitation to understanding brain diseases is the inability to access brain biopsies on living patients. As a result, researchers typically study blood cells from patients or examine post-mortem tissue. This is in stark contrast with diseases such as cancer, for which there are many existing repositories of highly characterized cells from patients.

The new biobank offers a way to push beyond this limitation.

 

A Big Step Forward

While the biobank is already a boon to the scientific community, researchers at MGH and the HMS Department of Biomedical Informatics will be adding additional layers of molecular data to all of the cell samples. This information will include whole genome sequencing and transcriptomic and epigenetic profiling of brain cells made from the stem cell lines.

Collaborators in the HMS Department of Neurobiology, led by Michael Greenberg, department chair and Nathan Marsh Pusey Professor of Neurobiology,  will also work to examine characteristics of other types of neurons derived from these stem cells.

“This can potentially alter the entire way we look at and diagnose many neuropsychiatric conditions,” said Perlis.

One example may be to understand how the cellular responses to medication correspond to the patient’s documented responses, comparing in vitro with in vivo. “This would be a big step forward in bringing precision medicine to psychiatry,” Perlis said.

“It’s important to recall that in the field of genomics, we didn’t find interesting connections to disease until we had large enough samples to really investigate these complex conditions,” said Kohane, chair of the HMS Department of Biomedical Informatics.

“Our hypothesis is that here we will require far fewer patients,” he said. “By measuring the molecular functioning of the cells of each patient rather than only their genetic risk, and combining that all that’s known of these people in terms of treatment response and cognitive function, we will discover a great deal of valuable information about these conditions.”

Added Perlis, “In the early days of genetics, there were frequent false positives because we were studying so few people. We’re hoping to avoid the same problem in making cellular models, by ensuring that we have a sufficient number of cell lines to be confident in reporting differences between patient groups.”

The generation of stem cell lines and characterization of patients and brain cell lines is funded jointly by the the National Institute of Mental Health, the National Human Genome Research Institute and a grant from the Centers of Excellence in Genomic Science program.

 

On C.T.E. and Athletes, Science Remains in Its Infancy

Se Hoon ChoiYoung Hye KimMatthias Hebisch, et al.

http://www.nature.com/articles/nature13800.epdf

Alzheimer’s disease is the most common form of dementia, characterized by two pathological hallmarks: amyloid-β plaques and neurofibrillary tangles1. The amyloid hypothesis of Alzheimer’s disease posits that the excessive accumulation of amyloid-β peptide leads to neurofibrillary tangles composed of aggregated hyperphosphorylated tau2, 3. However, to date, no single disease model has serially linked these two pathological events using human neuronal cells. Mouse models with familial Alzheimer’s disease (FAD) mutations exhibit amyloid-β-induced synaptic and memory deficits but they do not fully recapitulate other key pathological events of Alzheimer’s disease, including distinct neurofibrillary tangle pathology4, 5. Human neurons derived from Alzheimer’s disease patients have shown elevated levels of toxic amyloid-β species and phosphorylated tau but did not demonstrate amyloid-β plaques or neurofibrillary tangles6, 7, 8, 9, 10, 11. Here we report that FAD mutations in β-amyloid precursor protein and presenilin 1 are able to induce robust extracellular deposition of amyloid-β, including amyloid-β plaques, in a human neural stem-cell-derived three-dimensional (3D) culture system. More importantly, the 3D-differentiated neuronal cells expressing FAD mutations exhibited high levels of detergent-resistant, silver-positive aggregates of phosphorylated tau in the soma and neurites, as well as filamentous tau, as detected by immunoelectron microscopy. Inhibition of amyloid-β generation with β- or γ-secretase inhibitors not only decreased amyloid-β pathology, but also attenuated tauopathy. We also found that glycogen synthase kinase 3 (GSK3) regulated amyloid-β-mediated tau phosphorylation. We have successfully recapitulated amyloid-β and tau pathology in a single 3D human neural cell culture system. Our unique strategy for recapitulating Alzheimer’s disease pathology in a 3D neural cell culture model should also serve to facilitate the development of more precise human neural cell models of other neurodegenerative disorders.

 

 

Figure 2: Robust increases of extracellular amyloid-β deposits in 3D-differentiated hNPCs with FAD mutations.close

Robust increases of extracellular amyloid-[bgr] deposits in 3D-differentiated hNPCs with FAD mutations.

a, Thin-layer 3D culture protocol. HC, histochemistry; IF, immunofluorescence; IHC, immunohistochemistry. b, Amyloid-β deposits in 6-week differentiated control and FAD ReN cells in 3D Matrigel (green, GFP; blue, 3D6; scale bar, …

 

Stem Cell-Based Spinal Cord Repair Enables Robust Corticospinal Regeneration

 

Novel use of EPR spectroscopy to study in vivo protein structure

http://www.news-medical.net/whitepaper/20160315/Novel-use-of-EPR-spectroscopy-to-study-in-vivo-protein-structure.aspx

α-synuclein

α-synuclein is a protein found abundantly throughout the brain. It is present mainly at the neuron ends where it is thought to play a role in ensuring the supply of synaptic vesicles in presynaptic terminals, which are required for the release of neurotransmitters to relay signals between neurons. It is critical for normal brain function.

However, α-synuclein is also the primary protein component of the cerebral amyloid deposits characteristic of Parkinson’s disease and its precursor is found in the amyloid plaques of Alzheimer’s disease. Although α-synuclein is present in all areas of the brain, these disease-state amyloid plaques only arise in distinct areas.

Alpha-synuclein protein. May play role in Parkinson’s and Alzheimer’s disease.  © molekuul.be / Shutterstock.com

Imaging of isolated samples of α-synuclein in vitro indicate that it does not have the precise 3D folded structure usually associated with proteins. It is therefore classed as an intrinsically disordered protein. However, it was not known whether the protein also lacked a precise structure in vivo.

There have been reports that it can form helical tetramers. Since the 3D structure of a biological protein is usually precisely matched to the specific function it performs, knowing the structure of α-synuclein within a living cell will help elucidate its role and may also improve understanding of the disease states with which it is associated.

If α-synuclein remains disordered in vivo, it may be possible for the protein to achieve different structures, and have different properties, depending on its surroundings.

Techniques for determining protein structure

It has long been known that elucidating the structure of a protein at an atomic level is fundamental for understanding its normal function and behavior. Furthermore, such knowledge can also facilitate the development of targeted drug treatments. Unfortunately, observing the atomic structure of a protein in vivo is not straightforward.

X-ray diffraction is the technique usually adopted for visualizing structures at atomic resolution, but this requires crystals of the molecule to be produced and this cannot be done without separating the molecules of interest from their natural environment. Such processes can modify the protein from its usual state and, particularly with complex structures, such effects are difficult to predict.

The development of nuclear magnetic resonance (NMR) spectroscopy improved the situation by making it possible for molecules to be analyzed under in vivo conditions, i.e. same pH, temperature and ionic concentration.

More recently, increases in the sensitivity of NMR and the use of isotope labelling have enabled determinations of the atomic level structure and dynamics of proteins to be determined within living cells1. NMR has been used to determine the structure of a bacterial protein within living cells2 but it is difficult to achieve sufficient quantities of the required protein within mammalian cells and to keep the cells alive for NMR imaging to be conducted.

Electron paramagnetic resonance (EPR) spectroscopy for determining protein structure

Recently, researchers have managed to overcome these obstacles by using in-cell NMR and electron paramagnetic resonance (EPR) spectroscopy. EPR spectroscopy is a technique that is similar to NMR spectroscopy in that it is based on the measurement and interpretation of the energy differences between excited and relaxed molecular states.

In EPR spectroscopy it is electrons that are excited, whereas in NMR signals are created through the spinning of atomic nuclei. EPR was developed to measure radicals and metal complexes, but has also been utilized to study the dynamic organization of lipids in biological membranes3.

EPR has now been used for the first time in protein structure investigations and has provided atomic-resolution information on the structure of α-synuclein in living mammalians4,5.

Bacterial forms of the α-synuclein protein labelled with 15N isotopes were introduced into five types of mammalian cell using electroporation. Concentrations of α-synuclein close to those found in vivo were achieved and the 15N isotopes allowed the protein to be clearly defined from other cellular components by NMR. The conformation of the protein was then determined using electron paramagnetic resonance (EPR).

The results showed that within living mammalian cells α-synuclein remains as a disordered and highly dynamic monomer. Different intracellular environments did not induce major conformational changes.

Summary

The novel use of EPR spectroscopy has resolved the mystery surrounding the in vivo conformation of α-synuclein. It showed that α-synuclein maintains its disordered monomeric form under physiological cell conditions. It has been demonstrated for the first time that even in crowded intracellular environments α-synuclein does not form oligomers, showing that intrinsic structural disorder can be sustained within mammalian cells.

References

  1. Freedberg DI and Selenko P. Live cell NMR Annu. Rev. Biophys. 2014;43:171–192.
  2. Sakakibara D, et al. Protein structure determination in living cells by in-cell NMR spectroscopy. Nature 2009;458:102–105.
  3. Yashroy RC. Magnetic resonance studies of dynamic organisation of lipids in chloroplast membranes. Journal of Biosciences 1990;15(4):281.
  4. Alderson TA and Bax AD. Parkinson’s Disease. Disorder in the court. Nature 2016; doi:10.1038/nature16871.
  5. Theillet FX, et al. Structural disorder of monomeric α-synuclein persists in mammalian cells. Nature 2016; doi:10.1038/nature16531.

 

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The Pharmaceutical Consulting Consortium International (PCCI) June Meeting: Envisage-Wistar Partnership and Immunacel LLC

An early stage healthcare venture creation and management firm

Presenter: Vic Subbu, COO of Immunacel & Managing Partner of Envisage and Heather Steinman, VP of Business Development & Executive Director Tech Transfer Wistar Institute

Monday, June 8, 2015

Embassy Suites, Chesterbrook, Pennsylvania (directions)

Announcement from the PCCI website:

Much has been said lately about how to improve the tech transfer situation. Wistar is meeting this challenge. Immunacel is the first of a series of developmental challenges and the Envisage-Wistar partnership solution becomes the meat of the evening’s discussion.

The Wistar Institute is the nation’s first independent institution devoted to medical research and training. The Wistar Institute has evolved from its beginnings as an anatomical teaching museum to its present-day status as an international leader in basic biomedical research.

Envisage LLC is an early stage healthcare venture creation and management firm. By focusing on key healthcare segments, Envisage aims to identify and advance promising healthcare innovations into value-add ventures.

IMMUNACCEL LLC is a Wistar Institute spin-out focused on accelerating the development of immune-mediated treatments for cancer and other unmet medical needs:

MMUNACCEL’s 3-D cancer-immune cell organotypic culture system is a physiologically relevant culture system utilizing primary human cancer cells and cytotoxic T cells (CTL) generated from patient T-cells, amongst fibroblasts and collagen assembled in a 3-D organotypic model.

Other related articles on PCCI and Philadelphia Biotech were published in this Open Access Online Scientific Journal, include the following:

PCCI’s 7th Annual Roundtable “Crowdfunding for Life Sciences: A Bridge Over Troubled Waters?” May 12 2014 Embassy Suites Hotel, Chesterbrook PA 6:00-9:30 PM

Protecting Your Biotech IP and Market Strategy: Notes from Life Sciences Collaborative 2015 Meeting

The Vibrant Philly Biotech Scene: Focus on KannaLife Sciences and the Discipline and Potential of Pharmacognosy

The Vibrant Philly Biotech Scene: Focus on Computer-Aided Drug Design and Gfree Bio, LLC

The Vibrant Philly Biotech Scene: Focus on Vaccines and Philimmune, LLC

The Bioscience Crowdfunding Environment: The Bigger Better VC?

R&D Alliances between Big Pharma and Academic Research Centers: Pharma’s Realization that Internal R&D Groups alone aren’t enough

BIO Partnering: Intersection of Academic and Industry: BIO INTERNATIONAL CONVENTION June 23-26, 2014 | San Diego, CA

Diagnostics and Biomarkers: Novel Genomics Industry Trends vs Present Market Conditions and Historical Scientific Leaders Memoirs

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3D-Printing in the Life Sciences Conference, July 8-9, 2015, Boston, MA – Organ-on-a-Chip World Congress

 

Reporter: Aviva Lev-Ari, PhD, RN

Dear Researchers and Industry Participants,SELECTBIO is organizing the Organ-on-a-Chip World Congress & 3D-Printing in the Life Sciences Conference, July 8-9, 2015, Boston, USA. Bringing together the top researchers and key opinion leaders in these emerging fields, this conference offers extensive scientific learning and networking opportunities with speakers and delegates from around the world.

This Congress Focuses on the Intersection of Microfluidics and Bioprinting, Biofabrication – An Emerging and Expanding Field.Registered Delegates Receive Access to both Co-located, Concurrent Conference Tracks Enabling Mix-and-Match of Presentations as well as Maximal Networking Opportunities.
Topics Covered
Additive Manufacturing Technologies
Application Areas for 3D-Printing in Medicine as well as Broadly in the Life Sciences
Artery-on-a-Chip for Cardiovascular Disease Research
Bioassembly Approaches
Biofabrication and Bioprinting Technologies and Tools
Bioinks and Substrates for Bioprinting/3D-Printing
Bioprinters
Brain-on-a-Chip
Emerging Trends in 3D-Printing (Bioprinting) in the Life Sciences
Gut-on-a-Chip
Liver-on-a-Chip for Toxicity Screening/Toxicology Studies
Lung-on-a-Chip
Microfluidics/LOAC for Constructing Organ-on-a-Chip/Tissue-on-a-Chip/Body-on-a-Chip
Organ-on-a-Chip/Body-on-a-Chip Assembly/Synthetic Biology
Technologies for Organ-on-a-Chip Biofabrication
Technology Platforms for 3D-Printing in Life Sciences
Confirmed Keynote Speakers
Gabor Forgacs, George H. Vineyard Professor of Biophysics, University of Missouri; Founder,Modern Meadow
Geraldine A. Hamilton, President and Chief Scientific Officer, Emulate
Hod Lipson, Professor of Engineering, Cornell University
Kristin Fabre, Scientific Program Manager, NIH National Center for Advancing Translational Science (NCATS)
Martin Yarmush, Director, Center for Engineering in Medicine, Massachusetts General Hospital (MGH)
Michael Gelinsky, Head of the Center for Translational Bone, Joint and Soft Tissue Research, Faculty of Medicine, Technische Universität Dresden
Michael Shuler, Professor of Engineering, Cornell University
Roger Kamm, Professor, Massachusetts Institute of Technology (MIT)
Scott Simon, Professor & Vice Chair-Department of Biomedical Engineering, University of California-Davis
Stuart Williams, Director, Bioficial Organs, University of Louisville
Wei Sun, National “Thousand-Talent” Distinguished Professor and Albert Soffa Chair Professor,Tsinghua University, Beijing, China, and Drexel University, USA
Confirmed Speakers Include
Albert Folch, President, 3DSkema and Associate Professor, Bioengineering Department, University of Washington
Ali Khademhosseini, Director, Biomaterials Innovation Research Center (BIRC) Professor of Medicine and Health Sciences and Technology, Brigham and Women’s Hospital/Harvard Medical School
Anthony Schiavo, Research Associate, Lux Research
James Hickman, Professor of NanoScience Technology, Chemistry, Biomolecular Science, Physics, Material Science and Electrical Engineering, University of Central Florida
Jason Spector, Associate Professor of Plastic Surgery, Director, Laboratory for Bioregenerative Medicine and Surgery, Weill Cornell Medical College
Jinah Jang, Researcher, Pohang University of Science and Technology (POSTECH) Korea
Jing Yang, Senior Research Fellow, University of Nottingham
Jonathan Butcher, Associate Professor, Cornell University
Jonathan Thon, Assistant Professor, Brigham and Women’s Hospital/Harvard Medical School, Co-Founder — Platelet BioGenesis
Jordan Miller, Assistant Professor of Engineering and Founder of the Advanced Manufacturing Research Program, Rice University
Ju Young Park, Division of Integrative Biosciences and Biotechnology, POSTECH Korea
Luiz Bertassoni, Assistant Professor, Oregon Health and Science University/The University of Sydney
Martin Stelzle, Head, The University of Tübingen
Matthew Hancock, Senior Engineer, Veryst Engineering, LLC
Megan L. McCain, Assistant Professor of Biomedical Engineering and Stem Cell Biology and Regenerative Medicine, University of Southern California
Olivier Guenat, Head, University of Berne-Switzerland
Paul Calvert, Professor, Department of Chemical Engineering, New Mexico Tech
Paul Vulto, Senior Researcher/Group Leader, Leiden University
Rahul S. Tare, Lecturer in Musculoskeletal Science and Bioengineering, University of Southampton, UK
Robert Esmond, Director, Sterne, Kessler, Goldstein & Fox P.L.L.C
Shannon Stott, Assistant Professor, Massachusetts General Hospital/Harvard Medical School
Teruo Fujii, Professor, Institute of Industrial Science, University of Tokyo
Uwe Marx, CEO TissUse, Technical University of Berlin
Pre-Conference Training Course on July 7, 2015 from 16:30-19:00
3D-Bioprinting: Technologies, Research Trends, Competitive Landscape, and Application Areas
For More Details on this Course, Please Click Here
For the Most Up-to-Date Conference Agendas for this Multi-Track Conference,
Please Click Here
Submit a Poster to Present your Research to a Worldwide Audience
To Sponsor, Exhibit or for More Information:Jeff Fan
Events Manager
SELECTBIO US
Telephone: 510-857-4865
jeff@selectbio.us
Register
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This email was sent from SELECTBIO Ltd to avivalev-ari@alum.berkeley.edu . If you received this email in error, please forward it to the appropriate department at your company. To unsubscribe from future emails, please use this link.SELECTBIO Ltd, Woodview, Bull Lane, Sudbury, CO10 0FD, United Kingdom

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Organ-on-a-Chip World Congress & 3D-Printing in Life Sciences Conference, July 8-9, 2015, Boston. Network with the Top Researchers in these Fields
Sent By:
Jeff Fan   On:Mar 03/25/15 3:09 PM
To: avivalev-ari@alum.berkeley.edu
Reply to: Jeff Fan

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