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Archive for the ‘Tissue Engineering and Regenerative Medicine’ Category


Skin Regeneration Therapy One of First Tissue Engineering Products Evaluated by FDA

Reporter: Irina Robu, PhD

Under the provisions of 21st Century Cures Act the U.S. Food and Drug Administration approved StrataGraft regenerative skin tissue as the first product designated as a Regenerative Medicine Advanced Therapy (RMAT) produced by Mallinckrodt Pharmaceuticals. StrataGraft is shaped using unmodified NIKS cells grown under standard operating procedures since the continuous NIKS skin cell line has been thoroughly characterized. StrataGraft products are virus-free, non-tumorigenic, and offer batch-to-batch genetic consistency.

Passed in 2016, the 21st Century act allows FDA to grant accelerated review approval to products which meet an RMAT designation. The RMAT designation includes debates of whether priority review and/or accelerated approval would be suitable based on intermediate endpoints that would be reasonably likely to predict long-term clinical benefit.

The designation includes products

  • defined as a cell therapy, therapeutic tissue engineering product, human cell and tissue product, or any combination product using such therapies or products;
  • intended to treat, modify, reverse, or cure a serious or life-threatening disease or condition; and
  • preliminary clinical evidence indicates the drug has the potential to address unmet medical needs for such disease or condition.

According to Steven Romano, M.D., Chief Scientific Officer and Executive Vice President, Mallinckrodt “We are very pleased the FDA has determined StrataGraft meets the criteria for RMAT designation, as this offers the possibility of priority review and/or accelerated approval. The company tissue-based therapy is under evaluation in a Phase 3 trial to assess its efficacy and safety in the advancement of autologous skin regeneration of complex skin defects due to thermal burns that contain intact dermal elements.

SOURCE

https://www.rdmag.com/news/2017/07/skin-regeneration-therapy-one-first-be-evaluated-fda

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3-D Printed Ovaries Produce Healthy Offspring

Reporter: Irina Robu, PhD

 

Each year about 120,000 organs are transplanted from one human being to another and most of the time is a living volunteer. But lack of suitable donors, predominantly means the supply of such organs is inadequate. Countless people consequently die waiting for a transplant which has led researchers to study the question of how to build organs from scratch.

One promising approach is to print them, but “bioprinting” remains largely experimental. Nevertheless, bioprinted tissue is before now being sold for drug testing, and the first transplantable tissues are anticipated to be ready for use in a few years’ time. The first 3D printed organ includes bioprosthetic ovaries which are constructed of 3D printed scaffolds that have immature eggs and have been successful in boosting hormone production and restoring fertility was developed by Teresa K. Woodruff, a reproductive scientist and director of the Women’s Health Research Institute at Feinberg School of Medicine, at Northwestern University, in Illinois.

What sets apart these bioprosthetic ovaries is the architecture of the scaffold. The material is made of gelatin made from broken-down collagen that is safe to humans which is self-supporting and can lead to building multiple layers.

The 3-D printed “scaffold” or “skeleton” is implanted into a female and its pores can be used to optimize how follicles, or immature eggs, get wedged within the scaffold. The scaffold supports the survival of the mouse’s immature egg cells and the cells that produce hormones to boost production. The open construction permits room for the egg cells to mature and ovulate, blood vessels to form within the implant enabling the hormones to circulate and trigger lactation after giving birth. The purpose of this scaffold is to recapitulate how an ovary would function.
The scientists’ only objective for developing the bioprosthetic ovaries was to help reestablish fertility and hormone production in women who have suffered adult cancer treatments and now have bigger risks of infertility and hormone-based developmental issues.

 

SOURCES

Printed human body parts could soon be available for transplant
https://www.economist.com/news/science-and-technology/21715638-how-build-organs-scratch

 

3D printed ovaries produce healthy offspring giving hope to infertile women

http://www.telegraph.co.uk/science/2017/05/16/3d-printed-ovaries-produce-healthy-offspring-giving-hope-infertile/

 

Brave new world: 3D-printed ovaries produce healthy offspring

http://www.naturalnews.com/2017-05-27-brave-new-world-3-d-printed-ovaries-produce-healthy-offspring.html

 

3-D-printed scaffolds restore ovary function in infertile mice

http://www.medicalnewstoday.com/articles/317485.php

 

Our Grandkids May Be Born From 3D-Printed Ovaries

http://gizmodo.com/these-mice-gave-birth-using-3d-printed-ovaries-1795237820

 

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Pharmacotyping Pancreatic Cancer Patients in the Future: Two Approaches – ORGANOIDS by David Tuveson and Hans Clevers and/or MICRODOSING Devices by Robert Langer

Curator: Aviva Lev-Ari, PhD, RN

 

This curation provides the resources for edification on Pharmacotyping Pancreatic Cancer Patients in the Future

 

  • Professor Hans Clevers at Clevers Group, Hubrecht University

https://www.hubrecht.eu/onderzoekers/clevers-group/

  • Prof. Robert Langer, MIT

http://web.mit.edu/langerlab/langer.html

Langer’s articles on Drug Delivery

https://scholar.google.com/scholar?q=Langer+on+Drug+Delivery&hl=en&as_sdt=0&as_vis=1&oi=scholart&sa=X&ved=0ahUKEwixsd2w88TTAhVG4iYKHRaIAvEQgQMIJDAA

organoids, which I know you’re pretty involved in with Hans Clevers. What are your plans for organoids of pancreatic cancer?

Organoids are a really terrific model of a patient’s tumour that you generate from tissue that is either removed at the time of surgery or when they get a small needle biopsy. Culturing the tissue and observing an outgrowth of it is usually successful and when you have the cells, you can perform molecular diagnostics of any type. With a patient-derived organoid, you can sequence the exome and the RNA, and you can perform drug testing, which I call ‘pharmacotyping’, where you’re evaluating compounds that by themselves or in combination show potency against the cells. A major goal of our lab is to work towards being able to use organoids to choose therapies that will work for an individual patient – personalized medicine.

Organoids could be made moot by implantable microdevices for drug delivery into tumors, developed by Bob Langer. These devices are the size of a pencil lead and contain reservoirs that release microdoses of different drugs; the device can be injected into the tumor to deliver drugs, and can then be carefully dissected out and analyzed to gain insight into the sensitivity of cancer cells to different anticancer agents. Bob and I are kind of engaged in a friendly contest to see whether organoids or microdosing devices are going to come out on top. I suspect that both approaches will be important for pharmacotyping cancer patients in the future.

From the science side, we use organoids to discover things about pancreatic cancer. They’re great models, probably the best that I know of to rapidly discover new things about cancer because you can grow normal tissue as well as malignant tissue. So, from the same patient you can do a comparison easily to find out what’s different in the tumor. Organoids are crazy interesting, and when I see other people in the pancreatic cancer field I tell them, you should stop what you’re doing and work on these because it’s the faster way of studying this disease.

SOURCE

Other related articles on Pancreatic Cancer and Drug Delivery published in this Open Access Online Scientific Journal include the following:

 

Pancreatic Cancer: Articles of Note @PharmaceuticalIntelligence.com

Curator: Aviva Lev-Ari, PhD, RN

https://pharmaceuticalintelligence.com/2016/05/26/pancreatic-cancer-articles-of-note-pharmaceuticalintelligence-com/

Keyword Search: “Pancreatic Cancer” – 275 Article Titles

https://pharmaceuticalintelligence.wordpress.com/wp-admin/edit.php?s=Pancreatic+Cancer&post_status=all&post_type=post&action=-1&m=0&cat=0&paged=1&action2=-1

Keyword Search: Drug Delivery: 542 Articles Titles

https://pharmaceuticalintelligence.wordpress.com/wp-admin/edit.php?s=Drug+Delivery&post_status=all&post_type=post&action=-1&m=0&cat=0&paged=1&action2=-1

Keyword Search: Personalized Medicine: 597 Article Titles

https://pharmaceuticalintelligence.wordpress.com/wp-admin/edit.php?s=Personalized+Medicine&post_status=all&post_type=post&action=-1&m=0&cat=0&paged=1&action2=-1

  • Cancer Biology & Genomics for Disease Diagnosis, on Amazon since 8/11/2015

http://www.amazon.com/dp/B013RVYR2K

 

 

VOLUME TWO WILL BE AVAILABLE ON AMAZON.COM ON MAY 1, 2017

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cvd-series-a-volume-iv-cover

Series A: e-Books on Cardiovascular Diseases

Series A Content Consultant: Justin D Pearlman, MD, PhD, FACC

VOLUME FOUR

Regenerative and Translational Medicine

The Therapeutic Promise for

Cardiovascular Diseases

  • on Amazon since 12/26/2015

http://www.amazon.com/dp/B019UM909A

 

by  

Larry H Bernstein, MD, FCAP, Senior Editor, Author and Curator

and

Aviva Lev-Ari, PhD, RN, Editor and Curator

 

Part One:

Cardiovascular Diseases,Translational Medicine (TM) and Post TM

Introduction to Part 1: Cardiovascular Diseases,Translational Medicine (TM) and Post TM

Chapter 1: Translational Medicine Concepts

1.0 Post-Translational Modification of Proteins

1.1 Identifying Translational Science within the Triangle of Biomedicine

1.2 State of Cardiology on Wall Stress, Ventricular Workload and Myocardial Contractile Reserve: Aspects of Translational Medicine (TM)

1.3 Risk of Bias in Translational Science

1.4 Biosimilars: Intellectual Property Creation and Protection by Pioneer and by Biosimilar Manufacturers

Chapter 2: Causes and the Etiology of Cardiovascular Diseases: Translational Approaches for Cardiothoracic Medicine

2.1 Genomics

2.1.1 Genomics-Based Classification

2.1.2  Targeting Untargetable Proto-Oncogenes

2.1.3  Searchable Genome for Drug Development

2.1.4 Zebrafish Study Tool

2.1.5  International Human Genome Sequencing Consortium (2004) Finishing the euchromatic sequence of the human genome.

2.2  Proteomics

2.2.1 The Role of Tight Junction Proteins in Water and Electrolyte Transport

2.2.2 Selective Ion Conduction

2.2.3 Translational Research on the Mechanism of Water and Electrolyte Movements into the Cell

2.2.4 Inhibition of the Cardiomyocyte-Specific Kinase TNNI3K ­ Oxidative Stress

2.2.5 Oxidized Calcium Calmodulin Kinase and Atrial Fibrillation

2.2.6 S-Nitrosylation in Cardiac Ischemia and Acute Coronary Syndrome

2.2.7 Acetylation and Deacetylation

2.2.8 Nitric Oxide Synthase Inhibitors (NOS-I) 

2.3 Cardiac and Vascular Signaling

2.3.1 The Centrality of Ca(2+) Signaling and Cytoskeleton Involving Calmodulin Kinases and Ryanodine Receptors in Cardiac Failure, Arterial Smooth Muscle, Post-ischemic Arrhythmia, Similarities and Differences, and Pharmaceutical Targets

2.3.2 Leptin Signaling in Mediating the Cardiac Hypertrophy associated with Obesity

2.3.3 Triggering of Plaque Disruption and Arterial Thrombosis

2.3.4 Sensors and Signaling in Oxidative Stress

2.3.5 Resistance to Receptor of Tyrosine Kinase

2.3.6  S-nitrosylation signaling in cell biology.

2.4  Platelet Endothelial Interaction

2.4.1 Platelets in Translational Research ­ 1

2.4.2 Platelets in Translational Research ­ 2: Discovery of Potential Anti-platelet Targets

2.4.3 The Final Considerations of the Role of Platelets and Platelet Endothelial Reactions in Atherosclerosis and Novel Treatments

2.4.4 Endothelial Function and Cardiovascular Disease
Larry H Bernstein, MD, FCAP

2.5 Post-translational modifications (PTMs)

2.5.1 Post-Translational Modifications

2.5.2.  Analysis of S-nitrosylated Proteins

2.5.3  Mechanisms of Disease: Signal Transduction: Akt Phosphorylates HK-II at Thr-473 and Increases Mitochondrial HK-II Association to Protect Cardiomyocytes

2.5.4  Acetylation and Deacetylation of non-Histone Proteins

2.5.5  Study Finds Low Methylation Regions Prone to Structural Mutation

2.6 Epigenetics and lncRNAs

2.6.1 The Magic of the Pandora’s Box : Epigenetics and Stemness with Long non-coding RNAs (lincRNA)

2.6.2 The SILENCE of the Lambs” Introducing The Power of Uncoded RNA

2.6.3 Long Noncoding RNA Network regulates PTEN Transcription

2.6.4 How mobile elements in “Junk” DNA promote cancer. Part 1: Transposon-mediated tumorigenesis.

2.6.5 Transposon-mediated Gene Therapy improves Pulmonary Hemodynamics and attenuates Right Ventricular Hypertrophy: eNOS gene therapy reduces Pulmonary vascular remodeling and Arterial wall hyperplasia

2.6.6 Junk DNA codes for valuable miRNAs: non-coding DNA controls Diabetes

2.6.7 Targeted Nucleases

2.6.8 Late Onset of Alzheimer’s Disease and One-carbon Metabolism
Dr. Sudipta Saha

2.6.9 Amyloidosis with Cardiomyopathy

2.6.10 Long non-coding RNAs: Molecular Regulators of Cell Fate

2.7 Metabolomics

2.7.1 Expanding the Genetic Alphabet and Linking the Genome to the Metabolome

2.7.2 How Methionine Imbalance with Sulfur-Insufficiency Leads to Hyperhomocysteinemia

2.7.3 A Second Look at the Transthyretin Nutrition Inflammatory Conundrum

2.7.4 Transthyretin and Lean Body Mass in Stable and Stressed State

2.7.5 Hyperhomocysteinemia interaction with Protein C and Increased Thrombotic Risk

2.7.6 Telling NO to Cardiac Risk

2.8 Mitochondria and Oxidative Stress

2.8.1 Reversal of Cardiac Mitochondrial Dysfunction

2.8.2 Calcium Signaling, Cardiac Mitochondria and Metabolic Syndrome

2.8.3. Mitochondrial Dysfunction and Cardiac Disorders

2.8.4 Mitochondrial Metabolism and Cardiac Function

2.8.5 Mitochondria and Cardiovascular Disease: A Tribute to Richard Bing

2.8.6 MIT Scientists on Proteomics: All the Proteins in the Mitochondrial Matrix Identified

2.8.7 Mitochondrial Dynamics and Cardiovascular Diseases

2.8.8 Mitochondrial Damage and Repair under Oxidative Stress

2.8.9 Nitric Oxide has a Ubiquitous Role in the Regulation of Glycolysis -with a Concomitant Influence on Mitochondrial Function

2.8.10 Mitochondrial Mechanisms of Disease in Diabetes Mellitus

2.8.11 Mitochondria Dysfunction and Cardiovascular Disease – Mitochondria: More than just the “Powerhouse of the Cell”

Chapter 3: Risks and Biomarkers for Diagnosis and Prognosis in Translational Cardiothoracic Medicine

3.1 Biomarkers. Diagnosis and Management: Biomarkers. Present and Future.

3.2 Landscape of Cardiac Biomarkers for Improved Clinical Utilization

3.3 Achieving Automation in Serology: A New Frontier in Best

3.4 Accurate Identification and Treatment of Emergent Cardiac Events

3.5 Prognostic Marker Importance of Troponin I in Acute Decompensated Heart Failure (ADHF)

3.6 High-Sensitivity Cardiac Troponin Assays Preparing the United States for High-Sensitivity Cardiac Troponin Assays

3.7 Voices from the Cleveland Clinic On Circulating apoA1: A Biomarker for a Proatherogenic Process in the Artery Wall

3.8 Triggering of Plaque Disruption and Arterial Thrombosis

3.9 Relationship between Adiposity and High Fructose Intake Revealed

3.10 The Cardio-Renal Syndrome (CRS) in Heart Failure (HF)

3.11 Aneuploidy and Carcinogenesis

3.12 “Sudden Cardiac Death,” SudD is in Ferrer inCode’s Suite of Cardiovascular Genetic Tests to be Commercialized in the US

Chapter 4: Therapeutic Aspects in Translational Cardiothoracic Medicine

4.1 Molecular and Cellular Cardiology

4.1.1 αllbβ3 Antagonists As An Example of Translational Medicine Therapeutics

4.1.2 Three-Dimensional Fibroblast Matrix Improves Left Ventricular Function post MI

4.1.3 Biomaterials Technology: Models of Tissue Engineering for Reperfusion and Implantable Devices for Revascularization

4.1.4 CELLWAVE Randomized Clinical Trial: Modest improvement in LVEF at 4 months ­ “Shock wave­facilitated intracoronary administration of BMCs” vs “Shock wave treatment alone”

4.1.5 Prostacyclin and Nitric Oxide: Adventures in vascular biology –  a tale of two mediators

4.1.6 Cardiac Contractility & Myocardium Performance: Ventricular Arrhythmiasand Non-ischemic Heart Failure – Therapeutic Implications for Cardiomyocyte Ryanopathy

4.1.7 Publications on Heart Failure by Prof. William Gregory Stevenson, M.D., BWH

4.2 Interventional Cardiology and Cardiac Surgery – Mechanical Circulatory Support and Vascular Repair

4.2.1 Mechanical Circulatory Support System, LVAD, RVAD, Biventricular as a Bridge to Heart Transplantation or as “Destination Therapy”: Options for Patients in Advanced Heart Failure

4.2.2 Heart Transplantation: NHLBI’s Ten Year Strategic Research Plan to Achieving Evidence-based Outcomes

4.2.3 Improved Results for Treatment of Persistent type 2 Endoleak after Endovascular Aneurysm Repair: Onyx Glue Embolization

4.2.4 Carotid Endarterectomy (CEA) vs. Carotid Artery Stenting (CAS): Comparison of CMMS high-risk criteria on the Outcomes after Surgery: Analysis of the Society for Vascular Surgery (SVS) Vascular Registry Data

4.2.5 Effect of Hospital Characteristics on Outcomes of Endovascular Repair of Descending Aortic Aneurysms in US Medicare Population

4.2.6 Hypertension and Vascular Compliance: 2013 Thought Frontier – An Arterial Elasticity Focus

4.2.7 Preventive Medicine Philosophy: Excercise vs. Drug, IF More of the First THEN Less of the Second

4.2.8 Cardio-oncology and Onco-Cardiology Programs: Treatments for Cancer Patients with a History of Cardiovascular Disease

Summary to Part One

 

Part Two:

Cardiovascular Diseases and Regenerative Medicine

Introduction to Part Two

Chapter 1: Stem Cells in Cardiovascular Diseases

1.1 Regeneration: Cardiac System (cardiomyogenesis) and Vasculature (angiogenesis)

1.2 Notable Contributions to Regenerative Cardiology by Richard T. Lee (Lee’s Lab, Part I)

1.3 Contributions to Cardiomyocyte Interactions and Signaling (Lee’s Lab, Part II)

1.4 Jmjd3 and Cardiovascular Differentiation of Embryonic Stem Cells

1.5 Stem Cell Therapy for Coronary Artery Disease (CAD)

1.6 Intracoronary Transplantation of Progenitor Cells after Acute MI

1.7 Progenitor Cell Transplant for MI and Cardiogenesis (Part 1)

1.8 Source of Stem Cells to Ameliorate Damage Myocardium (Part 2)

1.9 Neoangiogenic Effect of Grafting an Acellular 3-Dimensional Collagen Scaffold Onto Myocardium (Part 3)

1.10 Transplantation of Modified Human Adipose Derived Stromal Cells Expressing VEGF165

1.11 Three-Dimensional Fibroblast Matrix Improves Left Ventricular Function Post MI

Chapter 2: Regenerative Cell and Molecular Biology

2.1 Circulating Endothelial Progenitors Cells (cEPCs) as Biomarkers

2.2 Stem Cell Research — The Frontier at the Technion in Israel

2.3 Blood vessel-generating stem cells discovered

2.4 Heart Renewal by pre-existing Cardiomyocytes: Source of New Heart Cell Growth Discovered

2.5 The Heart: Vasculature Protection – A Concept-based Pharmacological Therapy including THYMOSIN

2.6 Innovations in Bio instrumentation for Measurement of Circulating Progenetor Endothelial Cells in Human Blood.

2.7 Endothelial Differentiation and Morphogenesis of Cardiac Precursor

Chapter 3: Therapeutics Levels In Molecular Cardiology

3.1 Secrets of Your Cells: Discovering Your Body’s Inner Intelligence (Sounds True, on sale May 1, 2013) by Sondra Barrett

3.2 Human Embryonic-Derived Cardiac Progenitor Cells for Myocardial Repair

3.3 Repair using iPPCs or Stem Cells

3.3.1 Reprogramming cell in Tissue Repair

3.3.2 Heart patients’ skin cells turned into healthy heart muscle cells

3.4 Arteriogenesis and Cardiac Repair: Two Biomaterials – Injectable Thymosin beta4 and Myocardial Matrix Hydrogel 

3.5 Cardiovascular Outcomes: Function of circulating Endothelial Progenitor Cells (cEPCs): Exploring Pharmaco-therapy targeted at Endogenous Augmentation of cEPCs

3.6 Calcium Cycling (ATPase Pump) in Cardiac Gene Therapy: Inhalable Gene Therapy for Pulmonary Arterial Hypertension and Percutaneous Intra-coronary Artery Infusion for Heart Failure: Contributions by Roger J. Hajjar, MD

Chapter 4: Research Proposals for Endogenous Augmentation of circulating Endothelial Progenitor Cells (cEPCs)

4.1 Peroxisome proliferator-activated receptor (PPAR-gamma) Receptors Activation: PPARγ transrepression for Angiogenesis in Cardiovascular Disease and PPARγ transactivation for Treatment of Diabetes

4.2 Clinical Trials Results for Endothelin System: Pathophysiological role in Chronic Heart Failure, Acute Coronary Syndromes and MI – Marker of Disease Severity or Genetic Determination?

4.3 Endothelin Receptors in Cardiovascular Diseases: The Role of eNOS Stimulation

4.4 Inhibition of ET-1, ETA and ETA-ETB, Induction of NO production, stimulation of eNOS and Treatment Regime with PPAR-gamma agonists (TZD): cEPCs Endogenous Augmentation for Cardiovascular Risk Reduction – A Bibliography

4.5 Positioning a Therapeutic Concept for Endogenous Augmentation of cEPCs — Therapeutic Indications for Macrovascular Disease: Coronary, Cerebrovascular and Peripheral

4.6 Endothelial Dysfunction, Diminished Availability of cEPCs, Increasing CVD Risk for Macrovascular Disease – Therapeutic Potential of cEPCs

4.7 Vascular Medicine and Biology: CLASSIFICATION OF FAST ACTING THERAPY FOR PATIENTS AT HIGH RISK FOR MACROVASCULAR EVENTS Macrovascular Disease – Therapeutic Potential of cEPCs

4.8 Cardiovascular Disease (CVD) and the Role of agent alternatives in endothelial Nitric Oxide Synthase (eNOS) Activation and Nitric Oxide Production

4.9 Resident-cell-based Therapy in Human Ischaemic Heart Disease: Evolution in the PROMISE of Thymosin beta4 for Cardiac Repair

4.10 Macrovascular Disease – Therapeutic Potential of cEPCs: Reduction Methods for CV Risk

4.11 Bystolic’s generic Nebivolol – positive effect on circulating Endothelial Proginetor Cells endogenous augmentation

4.12 Heart Vasculature – Regeneration and Protection of Coronary Artery Endothelium and Smooth Muscle: A Concept-based Pharmacological Therapy of a Combination Three Drug Regimen including THYMOSIN

Summary to Part Two

Epilogue to Volume Four

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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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The late Cambridge Mayor Alfred Vellucci welcomed Life Sciences Labs to Cambridge, MA – June 1976

Reporter: Aviva Lev-Ari, PhD, RN

How Cambridge became the Life Sciences Capital

Worth watching is the video below, which captures the initial Cambridge City Council hearing on recombinant DNA research from June 1976. The first speaker is the late Cambridge mayor Alfred Vellucci.

Vellucci hoped to pass a two-year moratorium on gene splicing in Cambridge. Instead, the council passed a three-month moratorium, and created a board of nine Cambridge citizens — including a nun and a nurse — to explore whether the work should be allowed, and if so, what safeguards would be necessary. A few days after the board was created, the pro and con tables showed up at the Kendall Square marketplace.

At the time, says Phillip Sharp, an MIT professor, Cambridge felt like a manufacturing town that had seen better days. He recalls being surrounded by candy, textile, and leather factories. Sharp hosted the citizens review committee at MIT, explaining what the research scientists there planned to do. “I think we built a relationship,” he says.

By early 1977, the citizens committee had proposed a framework to ensure that any DNA-related experiments were done under fairly stringent safety controls, and Cambridge became the first city in the world to regulate research using genetic material.

 

WATCH VIDEO

How Cambridge became the life sciences capital

Scott Kirsner can be reached at kirsner@pobox.com. Follow him on Twitter@ScottKirsner and on betaboston.com.

SOURCE

How Cambridge became the life sciences capital

http://www.betaboston.com/news/2016/03/17/how-cambridge-became-the-life-sciences-capital/

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Cardiomyocytes from mesenchmal stem cells?

Larry H. Bernstein, MD, FCAP, Curator

LPBI

Introduction: A just published article from the Gladstone Institute establishes that cardiac muscle can be generated from inducible explandable  cardiovascular progenitor cells.  However, while the study has validity, it leaves much to be explained, especially in light of the references to many previous studies to generate cardiomycytes for heart failure.

Skin Cells Opening the Door to the Possibility of Personalized Medicine for Heart Attack Patients

iceC-Figure6

https://beyondthedish.files.wordpress.com/2016/03/iecpcs-give-rise-to-cms-ecs-and-smcs-in-vivo-and-improve-cardiac-function-after-mi.jpg?w=652

 

ieCPCs Give Rise to CMs, ECs, and SMCs In Vivo and Improve Cardiac Function after MI

(A–E) Immunofluorescence analyses of RFP and CM (A), EC (B and C), and SMC (D and E) markers in tissue sections collected 2 weeks after transplanting RFP-labeled ieCPCs at passage 10 into infarcted hearts of immunodeficient mice. Scale bars represent 100 μm.

(F and G) Ejection fraction and fractional shortening of the left ventricle (LV) quantified by echocardiography. Results from two independent experiments were shown. D, days; W, weeks.

(H–J) Cardiac fibrosis was evaluated at eight levels (L1–L8) by Masson’s trichrome staining 12 weeks after coronary ligation. The ligation site is marked as X. Sections of representative hearts are shown in (I) with quantification in (J). Scar tissue (%) = (the sum of fibrotic area or length at L1–L8/the sum of LV area or circumference at L1–L8) × 100. Scale bars represent 500 μm.

(K) Quantification of LV circumference of mouse hearts 12 weeks after transplantation of 2nd MEFs or ieCPCs. Data were summarized from 48 sections for each group. Data are mean ± SE. p < 0.05.

“Cardiac progenitor cells could be ideal for heart regeneration,” said senior author Sheng Ding, PhD, a senior investigator at Gladstone. “They are the closest precursor to functional heart cells, and, in a single step, they can rapidly and efficiently become heart cells, both in a dish and in a live heart. With our new technology, we can quickly create billions of these cells in a dish and then transplant them into damaged hearts to treat heart failure.”

 

Discussion:  The study raises some important questions.

  1. How are the cultured cells different than those used in previous studies?
  2. Cardiomyocytes and fibroblasts are both of mesodermal origin.  What determines which way the stem cell line will differentiate?
  3. What is the difference, if any, between the cell culture environment and the in vivo environment into which they are placed?
  4. There is a difference between chronic hypoxemia with congestive heart failure and acute coronary syndrome.  The experiment performed would be more apt to apply to post-ACS than to chronic heart failure.

 

Functional heart muscle regenerated in decellularized human hearts

March 11, 2016    http://snip.ly/txc6j#http://medicalxpress.com/news/2016-03-functional-heart-muscle-regenerated-decellularized.html

A partially recellularized human whole-heart cardiac scaffold, reseeded with human cardiomyocytes derived from induced pluripotent stem cells, being cultured in a bioreactor that delivers a nutrient solution and replicates some of the environmental conditions around a living heart. Credit: Bernhard Jank, MD, Ott Lab, Center for Regenerative Medicine, Massachusetts General Hospital

 

Massachusetts General Hospital (MGH) researchers have taken some initial steps toward the creation of bioengineered human hearts using donor hearts stripped of components that would generate an immune response and cardiac muscle cells generated from induced pluripotent stem cells (iPSCs), which could come from a potential recipient. The investigators described their accomplishments – which include developing an automated bioreactor system capable of supporting a whole human heart during the recellularization process—earlier this year in Circulation Research.

“Generating functional cardiac tissue involves meeting several challenges,” says Jacques Guyette, PhD, of the MGH Center for Regenerative Medicine (CRM), lead author of the report. “These include providing a structural scaffold that is able to support cardiac function, a supply of specialized cardiac , and a supportive environment in which cells can repopulate the scaffold to form mature tissue capable of handling complex cardiac functions.”

The research team is led by Harald Ott, MD, of the MGH CRM and the Department of Surgery, senior author of the paper. In 2008, Ott developed a procedure for stripping the living cells from a donor organ with a detergent solution and then repopulating the remaining extracellular matrix scaffold with organ-appropriate types of cells. Since then his team has used the approach to generate functional rat kidneys and lungs and has decellularized large-animal hearts, lungs and kidneys. This report is the first to conduct a detailed analysis of the matrix scaffold remaining after decellularization of whole human hearts, along with recellularization of the cardiac matrix in three-dimensional and whole-heart formats.

The study included 73 human hearts that had been donated through the New England Organ Bank, determined to be unsuitable for transplantation and recovered under research consent. Using a scaled-up version of the process originally developed in rat hearts, the team decellularized hearts from both brain-dead donors and from those who had undergone . Detailed characterization of the remaining cardiac scaffolds confirmed a high retention of matrix proteins and structure free of cardiac cells, the preservation of coronary vascular and microvascular structures, as well as freedom from human leukocyte antigens that could induce rejection. There was little difference between the reactions of organs from the two donor groups to the complex decellularization process.

Instead of using genetic manipulation to generate iPSCs from , the team used a newer method to reprogram skin cells with messenger RNA factors, which should be both more efficient and less likely to run into regulatory hurdles. They then induced the  to differentiate into or cardiomyocytes, documenting patterns of gene expression that reflected developmental milestones and generating cells in sufficient quantity for possible clinical application. Cardiomyocytes were then reseeded into three-dimensional matrix tissue, first into thin matrix slices and then into 15 mm fibers, which developed into spontaneously contracting tissue after several days in culture.

The last step reflected the first regeneration of human heart muscle from within a cell-free, human whole-heart matrix. The team delivered about 500 million iPSC-derived cardiomyocytes into the left ventricular wall of decellularized hearts. The organs were mounted for 14 days in an automated bioreactor system developed by the MGH team that both perfused the organ with nutrient solution and applied environmental stressors such as ventricular pressure to reproduce conditions within a living heart. Analysis of the regenerated tissue found dense regions of iPSC-derived cells that had the appearance of immature cardiac muscle tissue and demonstrated functional contraction in response to electrical stimulation.

“Regenerating a whole heart is most certainly a long-term goal that is several years away, so we are currently working on engineering a functional myocardial patch that could replace cardiac tissue damaged due a heart attack or heart failure,” says Guyette. “Among the next steps that we are pursuing are improving methods to generate even more – recellularizing a whole heart would take tens of billions—optimizing bioreactor-based culture techniques to improve the maturation and function of engineered cardiac tissue, and electronically integrating regenerated tissue to function within the recipient’s heart.”

Team leader Ott, an assistant professor of Surgery at Harvard Medical School, adds, “Generating personalized functional myocardium from patient-derived cells is an important step towards novel device-engineering strategies and will potentially enable patient-specific disease modeling and therapeutic discovery. Our team is excited to further develop both of these strategies in future projects.”

Explore further: A tool for isolating progenitor cells from human heart tissue could lead to heart repair

More information: Jacques P. Guyette et al. Bioengineering Human Myocardium on Native Extracellular MatrixNovelty and Significance, Circulation Research (2016). DOI: 10.1161/CIRCRESAHA.115.306874

 

Stem cell study in mice offers hope for treating heart attack patients

February 15, 2012  http://medicalxpress.com/news/2012-02-stem-cell-mice-heart-patients.html

 

Stem cell study in mice offers hope for treating heart attack patients

Cardiac stem cells, pictured here, give hope to patients who have suffered a heart attack. Credit: UCSF

A UCSF stem cell study conducted in mice suggests a novel strategy for treating damaged cardiac tissue in patients following a heart attack. The approach potentially could improve cardiac function, minimize scar size, lead to the development of new blood vessels – and avoid the risk of tissue rejection.

In the investigation, reported online in the journal PLoS ONE, the researchers isolated and characterized a novel type of cardiac stem cell from the tissue of middle-aged mice following a .

Then, in one experiment, they placed the in the culture dish and showed they had the ability to differentiate into cardiomyocytes, or “beating heart cells,” as well as endothelial cells and smooth muscle cells, all of which make up the heart.

In another, they made copies, or “clones,” of the cells and engrafted them in the tissue of other of the same genetic background who also had experienced heart attacks. The cells induced angiogenesis, or blood vessel growth, or differentiated, or specialized, into endothelial and smooth muscle cells, improving .

“These findings are very exciting,” said first author Jianqin Ye, PhD, MD, senior scientist at UCSF’s Translational Cardiac Stem Cell Program. First, “we showed that we can isolate these cells from the heart of middle-aged animals, even after a heart attack.” Second, he said, “we determined that we can return these cells to the animals to induce repair.”

Importantly, the stem cells were identified and isolated in all four chambers of the heart, potentially making it possible to isolate them from patients’ hearts by doing right ventricular biopsies, said Ye. This procedure is “the safest way of obtaining cells from the heart of live patients, and is relatively easy to perform,” he said.

“The finding extends the current knowledge in the field of native cardiac progenitor cell therapy,” said senior author Yerem Yeghiazarians, MD, director of UCSF’s Translational Cardiac Stem Cell Program and an associate professor at the UCSF Division of Cardiology. “Most of the previous research has focused on a different subset of cardiac progenitor cells. These novel cardiac precursor cells appear to have great therapeutic potential.”

The hope, he said, is that patients who have severe heart failure after a heart attack or have cardiomyopathy would be able to be treated with their own cardiac stem cells to improve the overall health and function of the heart. Because the cells would have come from the patients, themselves, there would be no concern of cell rejection after therapy.

The cells, known as Sca-1+ stem enriched in Islet (Isl-1) expressing cardiac precursors, play a major role in cardiac development. Until now, most of the research has focused on a different subset of cardiac progenitor, or early stage, cells known as, c-kit cells.

The Sca-1+ cells, like the c-kit cells, are located within a larger clump of cells called cardiospheres.

The UCSF researchers used special culture techniques and isolated Sca-1+ cells enriched in the Isl-1expressing cells, which are believed to be instrumental in the heart’s development. Since Isl-1 is expressed in the cell nucleus, it has been difficult to isolate them but the new technique enriches for this cell population.

The findings suggest a potential treatment strategy, said Yeghiazarians. “Heart disease, including heart attack and heart failure, is the number one killer in advanced countries. It would be a huge advance if we could decrease repeat hospitalizations, improve the quality of life and increase survival.” More studies are being planned to address these issues in the future.

An estimated 785,000 Americans will have a new heart attack this year, and 470,000 who will have a recurrent attack. Heart disease remains the number one killer in the United States, accounting for one out of every three deaths, according to the American Heart Association.

Medical costs of cardiovascular disease are projected to triple from $272.5 billion to $818.1 billion between now and 2030, according to a report published in the journal Circulation.

 

Sca-1+ Cardiosphere-Derived Cells Are Enriched for Isl1-Expressing Cardiac Precursors and Improve Cardiac Function after Myocardial Injury

Jianqin Ye , Andrew Boyle , Henry Shih , Richard E. Sievers , Yan Zhang , William Grossman , Harold S. Bernstein , Yerem Yeghiazarians
http://dx.doi.org:/10.1371/journal.pone.0030329

Background

Endogenous cardiac progenitor cells are a promising option for cell-therapy for myocardial infarction (MI). However, obtaining adequate numbers of cardiac progenitors after MI remains a challenge. Cardiospheres (CSs) have been proposed to have cardiac regenerative properties; however, their cellular composition and how they may be influenced by the tissue milieu remains unclear.

Methodology/Principal Finding

Using “middle aged” mice as CSs donors, we found that acute MI induced a dramatic increase in the number of CSs in a mouse model of MI, and this increase was attenuated back to baseline over time. We also observed that CSs from post-MI hearts engrafted in ischemic myocardium induced angiogenesis and restored cardiac function. To determine the role of Sca-1+CD45 cells within CSs, we cloned these from single cell isolates. Expression of Islet-1 (Isl1) in Sca-1+CD45 cells from CSs was 3-fold higher than in whole CSs. Cloned Sca-1+CD45 cells had the ability to differentiate into cardiomyocytes, endothelial cells and smooth muscle cells in vitro. We also observed that cloned cells engrafted in ischemic myocardium induced angiogenesis, differentiated into endothelial and smooth muscle cells and improved cardiac function in post-MI hearts.

Conclusions/Significance  

These studies demonstrate that cloned Sca-1+CD45 cells derived from CSs from infarcted “middle aged” hearts are enriched for second heart field (i.e., Isl-1+) precursors that give rise to both myocardial and vascular tissues, and may be an appropriate source of progenitor cells for autologous cell-therapy post-MI.

 

Incorporation of Mg particles into PDLLA regulates mesenchymal stem cell and macrophage responses

Sandra C. Cifuentes1, Fátima Bensiamar2,3, Amparo M. Gallardo-Moreno3,4, Tim A. Osswald5, José L. González-Carrasco1,3, et al.
J Biomed Materials Res Part A  104(4), pages 866–878, April 2016                    http://dx.doi.org:/10.1002/jbm.a.35625

In this work, we investigated a new approach to incorporate Mg particles within a PDLLA matrix using a solvent-free commercially available process. PDLLA/Mg composites were manufactured by injection moulding and the effects of Mg incorporated into PDLLA on MSC and macrophage responses were evaluated. Small amounts of Mg particles (≤1 wt %) do not cause thermal degradation of PDLLA, which retains its mechanical properties. PDLLA/Mg composites release hydrogen, alkaline products and Mg2+ ions without changing pH of culture media. Mg-containing materials provide a noncytotoxic environment that enhances MSC viability. Concentration of Mg2+ ions in extracts of MSCs increases with the increment of Mg content in the composites. Incorporation of Mg particles into PDLLA stimulates FN production, ALP activity, and VEGF secretion in MSCs, an effect mediated by degradation products dissolved from the composites. Degradation products of PDLLA induce an increase in MCP-1, RANTES, and MIP-1α secretion in macrophages while products of composites have minimal effect on these chemokines. Regulation of MSC behavior at the biomaterial’s interface and macrophage-mediated inflammatory response to the degradation products is related to the incorporation of Mg in the composites. These findings suggest that including small amounts of Mg particles into polymeric devices can be a valuable strategy to promote osseointegration and reduce host inflammatory response. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 866–878, 2016.

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