Stem Cell Therapy Might Improve Brain Function of Traumatic Brains Injury Patients


Accidents happen and sometimes really bad accidents happen; especially if they injure your head.  Traumatic brain injuries or TBIs can result from automobile accidents, explosions or other events that result from severe blows to the head.  TBIs  an adversely affect a patient and his/her family for long periods of time.  TBI patients can experience cognitive deficits that prevent them from thinking or speaking straight, and sensory deficits that prevent them from seeing, hearing or smelling properly.  Psychological problems can also result.  Essentially, TBIs represent a major challenge for modern medicine.

According to data from the Centers for Disease Control (CDC), 1.7 million Americans suffer from TBIs each year (of varying severity).  Of these, 275,000 are hospitalized for their injuries and approximately 52,000 of these patients die from their injuries.  In fact, TBIs contribute to one-third of all injury-related deaths in the United States each year.  More than 6.5 million patients are burdened by the deleterious effects of TBIs, and this leads to an economic burden of approximately $60 billion each year.

Currently, treatments for TBI are few and far between.  Neurosurgeons can use surgery to repair damaged blood vessels and tissues, and diminish swelling in the brain.  Beyond these rather invasive techniques, the options for clinicians are poor.

A new study by Charles S. Cox, professor of Pediatric Surgery and co-director of the Memorial Hermann Red Duke Trauma Institute, and his colleagues suggest that stem cell treatments might benefit TBI patients.  The results of this study were published in the journal Stem Cells.

This study enrolled 25 TBI patients.  Five of them received no treatment and served as controls, but the remaining 20 received gradually increasing dosages of their own bone marrow stem cells.  The harvesting, processing and infusion of the bone marrow cells occurred within 48 hours of injury.  Functional and cognitive results were measured with standard tests and brain imaging with magnetic resonance imaging and diffusion tensor imaging.

This work is an extension of extensive preclinical work done by Cox and his coworkers in laboratory animals and a phase I study that established that such stem cell transplantation are safe for human patients.  The implanted stem cells seem to quell brain inflammation and lessen the damage to the brain by the TBI.

Despite the fact that those TBI patients who received the stem cell treatments had greater degrees of brain damage, the treatment group showed better structural preservation of the brain and better functional outcomes than the control group.  Of particular interest was the decrease in indicators of inflammation as a result of the bone marrow cell-based infusions.

Cox said of this trial, “The data derived from this trial moves beyond just testing safety of this approach.”  He continued:  “We now have a hint of a treatment effect that mirrors our pre-clinical work, and were are now pursuing this approach in a phase IIb clinical trial sponsored by the Joint Warfighter Program within the US Army Medical Research Acquisition Activity, as well as our ongoing phase IIb pediatric severe TBI clinical trial; both using the same autonomous cell therapy.”

This an exciting study, but it is a small study.  While the safety of this procedure has been established, the precise dosage and long-term benefits will require further examination.  However it is a fine start to what may become the flowering of new strategies to treat TBI patients.

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Bone Marrow Mesenchymal Stem Cells Spontaneously Make Cartilage After Blockage of VEGF Signaling


Bone marrow-derived mesenchymal stem cells (MSCs) can be induced to make cartilage by incubating the cells with particular growth factors.  Unfortunately, batches of MSCs show respectable variability from patient-to-patient.  Therefore the growth factor-dependent method suffers from poor efficacy, limited reproducibility from batch-to-batch, and the cell types that are induced are not always terribly stable.  Finding a better way to make cartilage would certainly be a welcome addition to regenerative treatments,

Cartilage that coats the ends of bones is known as articulate cartilage, and articular cartilage lacks blood vessels.  Therefore, is it possible that inhibiting blood vessel formation could conveniently push MSCs to differentiate into cartilage-making chondrocytes?

A new paper by Ivan Martin and Andrea Basil from the University Hospital Basel and their colleagues have used this very strategy to induce cartilage formation in MSCs from bone marrow.

Martin and others isolated MSCs from bone marrow aspirates from human donors.  These cultured human MSCs were then genetically engineered with modified viruses to express a receptor for soluble vascular endothelial growth factor (VEGF) that binds this growth factor, but fails to induce any intracellular signals.  Such a receptor that binds the growth factor but does not induce any biological effects is called a “decoy receptor,” and decoy receptors efficiently sequester or vacuum up all the endogenous VEGF.  VEGF is the major blood vessel-inducing growth factor and it is heavily expressed during development, by cancer cells, and during healing.

After expressing the decoy VEGF receptor in these human MSCs, these genetically engineered cells were grown on collagen sponges and then implanted in immunodeficient mice.  If the implanted MSCs were not genetically engineered to express decoy VEGF receptors, they induced for formation of vascularized fibrous tissue.  However, the implantation of genetically engineered MSCs that expressed the decoy VEGF receptor efficiently and reproducibly differentiated into chondrocytes and formed hyaline cartilage. This is significant because headline cartilage is the very type of cartilage found at articular surfaces where the ends of bones come together to form joints.

In vivo chondrogenesis. Histological staining with Safranin-O for glycosaminoglycans and immunohistochemistry for type II collagen of engineered tissue generated by naïve (control) or sFlk-1 MSCs after 4 (A) or 12 (B) weeks in vivo. Fluorescence staining with DAPI (in blue) and a specific anti-human nuclei antibody (in red) of constructs generated by control or sFlk-1 MSCs after 4 (A) or 12 (B) weeks in vivo. Scale bar = 100 µm. Abbreviations: DAPI, 4′,6-diamidino-2-phenylindole; MSC, bone marrow-derived mesenchymal stromal/stem cell.
In vivo chondrogenesis. Histological staining with Safranin-O for glycosaminoglycans and immunohistochemistry for type II collagen of engineered tissue generated by naïve (control) or sFlk-1 MSCs after 4 (A) or 12 (B) weeks in vivo. Fluorescence staining with DAPI (in blue) and a specific anti-human nuclei antibody (in red) of constructs generated by control or sFlk-1 MSCs after 4 (A) or 12 (B) weeks in vivo. Scale bar = 100 µm. Abbreviations: DAPI, 4′,6-diamidino-2-phenylindole; MSC, bone marrow-derived mesenchymal stromal/stem cell.

This articular cartilage was quite stable and showed no signs of undergoing the chondrocytes enlargement found in terminally differentiated cartilage that is ready to form bone.  This stability was maintained for up to 12 weeks.

In vivo cartilage stability. Immunohistochemistry for type X collagen, BSP, and MMP-13 on sections of hypertrophic cartilage generated in vitro by MSCs (as a positive control) and on sections of the cartilaginous constructs generated in vivo by sFlk1 MSCs 12 weeks after implantation. Scale bar = 50 µm. Abbreviations: BSP, bone sialoprotein; MMP-13, metalloproteinase-13; MSC, bone marrow-derived mesenchymal stromal/stem cell.
In vivo cartilage stability. Immunohistochemistry for type X collagen, BSP, and MMP-13 on sections of hypertrophic cartilage generated in vitro by MSCs (as a positive control) and on sections of the cartilaginous constructs generated in vivo by sFlk1 MSCs 12 weeks after implantation. Scale bar = 50 µm. Abbreviations: BSP, bone sialoprotein; MMP-13, metalloproteinase-13; MSC, bone marrow-derived mesenchymal stromal/stem cell.

Why did inhibition of VEGF signaling induce cartilage?  Inhibition of angiogenesis induced low oxygen tensions, which activated a growth factor called transforming growth factor-β.  Activation of the TGF-beta pathway robustly enhanced the formation of articular cartilage.

In vitro chondrogenesis at different oxygen tensions. Histological staining with Safranin-O and immunohistochemistry for type II collagen on constructs generated in vitro by naïve MSC cultured with (A) or without (B) TGFβ3 supplementation at 2% or 20% of oxygen tension. Scale bar = 50 µm. Expression levels of the mRNA for type II and X collagen, Gremlin-1, IHH TGFβ1 were quantified in pellets generated by naïve bone marrow-derived mesenchymal stromal/stem cells (C, D) cultured in the two different oxygen tensions. ∆Ct values were normalized to expression of the GAPDH housekeeping gene, and results are shown as mean ± SD (n = 6 samples/group from 3 independent experiments). ∗, p < .05, ∗∗∗, p < .001. Abbreviations: GAPDH, glyceraldehyde-3-phosphate dehydrogenase; IHH, Indian hedgehog; TGFβ, transforming grown factor-β.
In vitro chondrogenesis at different oxygen tensions. Histological staining with Safranin-O and immunohistochemistry for type II collagen on constructs generated in vitro by naïve MSC cultured with (A) or without (B) TGFβ3 supplementation at 2% or 20% of oxygen tension. Scale bar = 50 µm. Expression levels of the mRNA for type II and X collagen, Gremlin-1, IHH TGFβ1 were quantified in pellets generated by naïve bone marrow-derived mesenchymal stromal/stem cells (C, D) cultured in the two different oxygen tensions. ∆Ct values were normalized to expression of the GAPDH housekeeping gene, and results are shown as mean ± SD (n = 6 samples/group from 3 independent experiments). ∗, p < .05, ∗∗∗, p < .001. Abbreviations: GAPDH, glyceraldehyde-3-phosphate dehydrogenase; IHH, Indian hedgehog; TGFβ, transforming grown factor-β.

Cartilage formation from MSCs was induced by blocking VEGF-mediated angiogenesis.  These results represent a remarkable advance in cartilage formation that can be used for regenerative treatments.  This cartilage formation was spontaneous and efficient and if it can be carried out with VEGF-inhibiting drugs rather than genetic engineering techniques, then we might have a transferable technique for making cartilage in the laboratory to treat osteoarthritis and other joint-based maladies.  Clinical trials will be required, but this is certainly an auspicious start.

The Amino Acid Valine Helps Maintain Hematopoietic Stem Cell Niches


Hematopoietic stem cells (HSCs) populate our bone marrow and divide throughout our lifetimes to provide the red and white blood cells we need to live. However, during normal, healthy times, only particular HSCs are hard at work dividing and making new blood cells. The remaining HSCs are maintained in a protective dormant state. However, in response to blood loss or physiological stress of some sort, dormant HSCs must wake from their “slumbers” and begin dividing to make the needed blood cells. Such conditions, it turns out, can cause HSCs to experience a good deal of damage to their genomes. A paper that was published in Nature last year by Walter Dagmar and colleagues (Vol 520: pp. 549) showed that repeatedly subjecting mice to conditions that required the activation of dormant HSCs (in this case they injected the mice with polyinosinic:polycytidylic acid or pI:pC to mimic a viral infection and induce a type I interferon response) resulted in the eventual collapse of the bone marrow’s ability to produce new blood cells. The awakened HSCs accumulated such large quantities of DNA damage, that they were no longer able to divide and produce viable progeny. How then can HSCs maintain the integrity of their genomes while still dividing and making new blood cells?

The answer to this question is not completely clear, but a new paper in the December 2 edition of Science magazine provides new insights into HSC physiology and function. This paper by Yuki Taya and others, working in the laboratories of Hiromitsu Nakauchi at the Institute for Stem Cell Biology and Regenerative Medicine at Stanford University School of Medicine, and Satoshi Yamazaki from the University of Tokyo, has shown that amino acid metabolism plays a vital role in HSC maintenance. As it turns out, the amino acid concentrations in bone marrow are approximately 100-fold higher than the concentrations of these same amino acids in circulating blood. Taya and others reasoned that such high amino acid concentrations must exist for reasons other than protein synthesis. Therefore, they designed dietary regimens that depleted mice for specific amino acids. Sure enough, when mice were fed valine-depleted diets, the HSCs of those mice lost their ability to repopulate the bone marrow.

Valine
Valine

After only two weeks of valine depletion, several nooks and crannies of the bone marrow – so-called stem cell “niches” – were devoid of HSCs. The bone marrow of such mice was easily reconstituted with HSCs from donor mice without the need for radiation or chemical ablation treatments.

Taya and others found that vascular endothelial stromal cells in the bone marrow secrete valine and that this secreted valine (which, by the way, is a branched-chain amino acid) is integral for maintaining HSC niches.

The excitement surrounding this finding is plain, since using harsh chemicals or radiation to destroy the bone marrow (a procedure known as “myeloablation”) causes premature ageing, infertility, lousy overall health, and other rather unpleasant side effects. Therefore, finding a “kinder, gentler” way to reconstitute the bone marrow would certainly be welcomed by patients and their physicians. However, valine depletion, even though it does not affect sterility, did cause 50% of the mice to die once valine was restored to the diet. This is due to a phenomenon known as the “refeeding effect” which has also been observed in human patients. Such side effects could probably be prevented by gradually returning valine to the diet. Taya and others also showed that cultured human HSCs required valine and another branched-chain amino acid, leucine. Since both leucine and valine are metabolized to alpha-ketoglutatate, which is used as a substrate for DNA-modifying enzymes, these amino acids might exert their effects through epigenetic modifications to the genome.

Alpha-ketoglutarate
Alpha-ketoglutarate

More work is needed in this area, but the Taya paper is a welcomed finding to a vitally important field.

Inhibition of AKT Kinase Increases Umbilical Cord Blood Growth in Culture and Engraftment in Mice


Dr. Yan Liu from the Department of Pediatrics and the Herman B Wells Center for Pediatric Research at the Indiana University School of Medicine in Indianapolis, Indiana and his colleagues have increased the engraftment efficiency of umbilical cord hematopoietic (blood cell-making) stem cells in immunodeficient mice. The technique developed by Lui and his colleagues is simple and increases the proliferation of umbilical cord blood hematopoietic stem cells (UCB-HSCs) in culture, which potentially solves several long-standing problems with umbilical cord blood transplantation.

Umbilical cord blood has been used in the clinic for more than 40 years in hematopoietic stem cell transplantation therapies to treat patients with bone marrow diseases or to reconstitute the bone of those cancer patients who had to have theirs wiped out to cure their leukemia or lymphoma.

One of the problems with umbilical cord blood transplantations, however, is the small amount of material in a typical cord blood collection and, therefore, the small number of hematopoietic stem cells (HSCs) available for transplantation. To ameliorate these shortcomings, hematologists will transplant more than one lot of cord blood (a so-called “double umbilical cord blood transplantation”), which, unfortunately, also increases the risk of immunological rejection (so-called Graft Versus Host response).

A second strategy to get around the low numbers of UCB-HSCs is to expand them in culture, which has proven difficult. However, some experiments have given us more than enough hope to suspect this this is a feasible option (see Flores-Guzmán P, et al., Stem Cells Transl Med. 2013 Nov;2(11):830-8; Bari S., et al., Biol Blood Marrow Transplant. 2015 Jun;21(6):1008-1; Pineault N, Abu-Khader A. Exp Hematol. 2015 Jul;43(7):498-513).

Dr. Lui and his coworkers wanted to examine the role of the signaling protein AKT (also known and protein kinase B) in UCB-HSC expansion in culture. To this end, they used silencing RNAs to knock-down AKT gene expression in cultured UCB-HSCs. AKT knock-down enhanced UCB-HSC quiescence and growth in culture. In a separate experiment, Lui and others treated human UCB-HSCs (so-called CD34+ cells) with a chemical that specifically inhibits AKT activity. Then they subjected these cells to a battery of tests in culture and in laboratory mice.

The results were astounding.  Treatment of human UCB-HSCs did not affect the identity of the HSCs and enhanced their ability to form isolated colonies in cell culture growth tests known as “replating assays.”  Additionally, the short-term inhibition of AKT with drugs also enhanced the ability of UBC-HSCs to repopulate the bone marrow of immunodeficient mice.

ubc-hsc-engraftment-improved-with-akt-inhibition

In summary, inhibition of AKT increases human UCB-HSC quiescence, growth potential, and engraftment in laboratory mice.

These interesting pre-clinical results suggest that AKT inhibitor can increase the expansion of UCB-HSCs in culture and potential increase their tendency of these cells to engraft in patients.

Gamida Cell Announces First Patient with Sickle Cell Disease Transplanted in Phase 1/2 Study of CordIn™ as the Sole Graft Source


An Israeli regenerative therapy company called Gamida Cell specializes in cellular and immune therapies to treat cancer and rare (“orphan”) genetic diseases. Gamida Cell’s main product is called NiCord, which provides patients who need new blood-making stem cells in their bone marrow an alternative to a bone marrow transplant. NiCord is umbilical cord blood that has been expanded in culture. In clinical trials to date, NiCord has rapidly engrafted into patients and the clinical outcomes of NiCord transplantation seem to be comparable to transplantation of peripheral blood.

Gamida Cell’s two products, NiCord and CordIn, as well as some other products under development utilize the company’s proprietary NAM platform technology to expand umbilical cord cells. The NAM platform technology has the remarkable capacity to preserve and enhance the functionality of hematopoietic stem cells from umbilical cord blood. CordIn is an experimental therapy for those rare non-malignant diseases in which bone marrow transplantation is the only currently available cure.

Gamida Cell has recently announced that the first patient with sickle cell disease (SCD) has been transplanted with their CordIn product.  Mark Walters, MD, Director of the Blood and Marrow Transplantation (BMT) Program is the Principal Investigator of this clinical trial. The patient received their transplant at UCSF Benioff Children’s Hospital Oakland.

CordIn, as previously mentioned, is an experimental therapy for rare non-malignant diseases, including hemoglobinopathies such as Sickel Cell Disease and thalassemia, bone marrow failure syndromes such as aplastic anemia, genetic metabolic diseases and refractory autoimmune diseases. CordIn potentially addresses a presently unmet medical need.

“The successful enrollment and transplantation of our first SCD patient with CordIn as a single graft marks an important milestone in our clinical development program. We are eager to demonstrate the potential of CordIn as a transplantation solution to cure SCD and to broaden accessibility to patients with rare genetic diseases in need of bone marrow transplantation,” said Gamida Cell CEO Dr. Yael Margolin. “In the first Phase 1/2 study with SCD, the expanded graft was transplanted along with a non-manipulated umbilical cord blood unit in a double graft configuration. In the second phase 1/2 study we updated the protocol from our first Phase 1/2 study so that patients would be transplanted with CordIn as a standalone graft, which is expanded from one full umbilical cord blood unit and enriched with stem cells using the company’s proprietary NAM technology.”

Somewhere in the vicinity of 100,000 patients in the U.S suffer from SCD; and around 200,000 patients suffer from thalassemia, globally. The financial burden of treating these patients over their lifetime is estimated at $8-9M. Bone marrow transplantation is the only clinically established cure for SCD, but only a few hundred SCD patients have actually received a bone marrow transplant in the last ten years, since most patients were not successful in finding a suitable match. Unrelated cord blood could be available for most of the patients eligible for transplantation, but, unfortunately, the rate of successful engraftment of un-expanded cord blood in these patients is low. Therefore, cord blood is usually not considered for SCD patients. Without a transplant, these patients suffer from very high morbidity and low quality of life.

Eight patients with SCD were transplanted in the first Phase 1/2 study performed in a double graft configuration. This study is still ongoing. Preliminary data from the first study will be summarized and published later this year. A Phase 1/2 of CordIn for the treatment of patients with aplastic anemia will commence later this year.

Genetic Switch to Making More Blood-Making Stem Cells Found


A coalition of stem cell scientists, co-led in Canada by Dr. John Dick, Senior Scientist, Princess Margaret Cancer Centre, University Health Network (UHN) and Professor, Department of Molecular Genetics, University of Toronto, and in the Netherlands by Dr. Gerald de Haan, Scientific Co-Director, European Institute for the Biology of Ageing, University Medical Centre Groningen, the Netherlands, have uncovered a genetic switch that can potentially increase the supply of stem cells for cancer patients who need transplantation therapy to fight their disease.

Their findings were published in the journal Cell Stem Cell and constitute proof-of-concept experiments that may provide a viable new approach to making more stem cells from umbilical cord blood.

“Stem cells are rare in cord blood and often there are not enough present in a typical collection to be useful for human transplantation. The goal is to find ways to make more of them and enable more patients to make use of blood stem cell therapy,” says Dr. Dick. “Our discovery shows a method that could be harnessed over the long-term into a clinical therapy and we could take advantage of cord blood being collected in various public banks that are now growing across the country.”

Currently, all patients who require stem cell transplants must be matched to an adult donor. The donor and the recipient must share a common set of cell surface proteins called “human leukocyte antigens” HLAs. HLAs are found on the surfaces of all nucleated cells in our bodies and these proteins are encoded by a cluster of genes called the “Major Histocompatibility Complex,” (MHC) which is found on chromosome six.

Map of MHC

There are two main types of MHC genes: Class I and Class II.

MHC Functions

Class I MHC contains three genes (HLA-A, B, and C). The three proteins encoded by these genes, HLA-A, -B, & -C, are found on the surfaces of almost all cells in our bodies. The exceptions are red blood cells and platelets, which do not have nuclei. Class II MHC genes consist of HLA-DR, DQ, and DP, and the proteins encoded by these genes are exclusive found on the surfaces of immune cells called “antigen-presenting cells” (includes macrophages, dendritic cells and B cells). Antigen-presenting cells recognize foreign substances in our bodies, grab them and, if you will, hold them up for everyone to see. The cells that usually respond to antigen presentation are immune cells called “T-cells.” T-cells are equipped with an antigen receptor that only binds antigens when those antigens are complexed with HLA proteins.

If you are given cells from another person who is genetically distinct from you, the HLA proteins on the surfaces of those cells are recognized by antigen-presenting cells as foreign substances. The antigen-presenting cells will them present pieces of the foreign HLA proteins on their surfaces, and T-cells will be sensitized to those proteins. These T-cells will them attack and destroy any cells in your body that have those foreign HLA proteins. This is the basis of transplant rejection and is the main reason transplant patients must continue to take drugs that prevent their T-cells from recognizing foreign HLA proteins as foreign.

When it comes to bone marrow transplantations, patients can almost never find a donor whose HLA surface proteins match perfectly. However, if the HLA proteins of the donor are too different from those of the recipient, then the cells from the bone marrow transplant attack the recipient’s cells and destroy them. This is called “Graft versus Host Disease” (GVHD). The inability of leukemia and lymphoma and other patients to receive bone marrow transplants is the unavailability of matching bone marrow. Globally, many thousands of patients are unable to get stem cell transplants needed to combat blood cancers such as leukemia because there is no donor match.

“About 40,000 people receive stem cell transplants each year, but that represents only about one-third of the patients who require this therapy,” says Dr. Dick. “That’s why there is a big push in research to explore cord blood as a source because it is readily available and increases the opportunity to find tissue matches. The key is to expand stem cells from cord blood to make many more samples available to meet this need. And we’re making progress.”

Umbilical cord blood, however, is different from adult bone marrow. The cells in umbilical cord blood are more immature and not nearly as likely to generate GVHD. Therefore, less perfect HLA matches can be used to treat patients in need of a bone marrow transplant. Unfortunately, umbilical cord blood has the drawback of have far fewer stem cells than adult bone marrow. If the number of blood-making (hematopoietic) stem cells in umbilical cord blood can be increased, then umbilical cord blood would become even more useful from a clinical perspective.

There has been a good deal of research into expanding the number of stem cells present in cord blood, the Dick/de Haan teams took a different approach. When a stem cell divides it produces a large number of “progenitor cells” that retain key properties of being able to develop into every one of the 10 mature blood cell types. These progenitor cells, however, have lost the critical ability to self-renew.

Dick and his colleagues analyzed mouse and human models of blood development, and they discovered that a microRNA called miR-125a is a genetic switch that is on in stem cells and controls self-renewal, but gets turned off in the progenitor cells.

“Our work shows that if we artificially throw the switch on in those downstream cells, we can endow them with stemness and they basically become stem cells and can be maintained over the long-term,” says Dr. Dick.

In their paper, Dick and de Haan showed that forced expression of miR-125 increases the number of hematopoietic stem cells in a living animal. Also, miR-125 induces stem cell potential in murine and human progenitor cells, and represses, among others, targets of the MAP kinase signaling pathway, which is important in differentiation of cells away from the stem cell fate. Furthermore, since miR-125 function and targets are conserved in human and mouse, what works in mice might very well work in human patients.

graphical abstract CSC_v9

This is proof-of-concept paper – no human trials have been conducted to date, but these data may be the beginnings of making more stem cells from banked cord blood to cure a variety of blood-based conditions.

Here’s to hoping.

C-Cure Shows Positive Trends in Phase 3 Trial but Fails to Meet Primary Endpoints


Celyad has pioneered a stem cell treatment for the heart called C-Cure. C-Cure consists of bone marrow stem cells that are isolated from a bone marrow aspiration that are then treated with a proprietary concoction that drives the cells to become cardiac progenitor cells, After this treatment, the cells are administered to the patient by means of a catheter where they will hopefully regenerate dead heart muscle tissue, make new blood vessels to replace clogged and dead blood vessels, and also smooth muscle cells to regulate the diameter of the newly-formed blood vessels.

The first clinical trial for C-Cure was announced in the Journal of the American College of Cardiology in June 2013. At this time, Celyad reported in their published data that all the mesenchymal stem cells (MSCs) had been successfully primed with their cocktails and successfully delivered to each patient. The desired cell dose was achieved in 75% of patients in cell delivery without complications occurred in 100% of cases. Fortunately, there were incidents of increased cardiac or systemic toxicity induced by the therapy.

Patients also showed some improvements. For example, left ventricular ejection fraction was improved by cell therapy (from 27.5 ± 1.0% to 34.5 ± 1.1%) versus standard of care alone (from 27.8 ± 2.0% to 28.0 ± 1.8%, p = 0.0001) and was associated with a reduction in left ventricular end-systolic volume (−24.8 ± 3.0 ml vs. −8.8 ± 3.9 ml, p = 0.001). Patients was received MSC therapy also improved their 6-min walk distance (+62 ± 18 m vs. −15 ± 20 m, p = 0.01) and had a superior composite clinical score encompassing cardiac parameters in tandem with New York Heart Association functional class, quality of life, physical performance, hospitalization, and event-free survival. The initial trial examined 13 control patients who received standard care and 20 patients who received their own MSCs and followed them for 2 years.

The strategy surrounding C-Cure is based on preclinical experiments in laboratory mice in which animals that had suffered heart attacks were treated with human MSCs that had been isolated from volunteers and pretreated with a cocktail that consisted of transforming growth factor-beta1, bone morphogenetic protein-4, activin A, retinoic acid, insulin-like growth factor-1, fibroblast growth factor-2, alpha-thrombin, and interleukin-6. This cocktail apparently drove the cells to form a heart-like fate. Then the cocktail-treated MSCs were implanted into the hearts of the mice and in the words of the paper’s abstract, the cells “achieved superior functional and structural benefit without adverse side effects. Engraftment into murine hearts was associated with increased human-specific nuclear, sarcomeric, and gap junction content along with induction of myocardial cell cycle activity.”. must say that I did not see definitive proof in this paper that the implanted cells actually formed new myocardium as opposed to inducing native cardiac stem cell population to form new myocardial cells.

This present trial is a Phase 3 clinical trial and it examined changes in patient mortality, morbidity, quality of life, six-minute walk test, and left ventricular structure and function at nine months after the treatment was given, The trial recruited 271 evaluable patients with chronic advanced symptomatic heart failure in 12 different countries in Europe and Israel. Like the trial before it, it was double blinded, placebo controlled.

First the good news: the procedure was well tolerated with no safety concerns.

The bad news was that a statistically-significant difference between the control group and treatment group was not observed 39 weeks after treatment. There is a silver lining to all this though: a positive trend was seen across all treatment groups. More interestingly, the primary endpoint was met (p=0.015) for a subset of the patients treated with their own MSCs. This subset represents 60% of the population of the CHART-1 study (baseline End Diastolic Volume (EDV) segmentation), which is pretty significant subset of the subject group. These patients showed less mortality and worsening of heart failure, better quality of life, an improved 6-minute walk test, end systolic volume and an improved ejection fraction.

On the strength of these data, Celyad thinks that this 60^ might represent the patient population for whom C-Cure is a viable treatment. What remains is to determine exactly who those patients are, the nature of their disease, and how much patients might be identified.

Dr. Christian Homsy, CEO of Celyad, commented: “For the first time in a randomized, double-blind, controlled, Phase III cell therapy study, a positive effect, consistent across all parameters tested, was observed for a substantial, clearly definable, group of heart failure patients.

CHART-1 has allowed us to better define the patient population that would benefit from C-Cure®. We are excited by the prospects for C-Cure® as a new potential treatment option for a highly relevant heart failure population. We are confident that the results will generate interest from potential partners that could accelerate the development and commercialization of C-Cure®.”

Prof. Jozef Bartunek, CHART-1 principal co-investigator, said: “This pioneering study has contributed greatly to our understanding of heart failure disease and the place of regenerative medicine in its management. The results seen for a large clinically relevant number of the patients are ground breaking. We look forward to completing the full analysis and making the data available to the medical community at ESC.

On behalf of the CHART 1 steering committee we wish to thank the patients and families who were enrolled in the study as well as all the physicians and medical teams that made this study possible.”

Prof. Gerasimos Filippatos, Immediate Past-President of the Heart Failure Association of the European Society of Cardiology, member of the CHART-1 dissemination committee, said, “The CHART-1 results have identified a well-defined group of patients with symptomatic heart failure despite optimal therapy. Those patients are a large subset of the heart failure population and present specific therapeutic challenges. The outcome of CHART-1 indicate those patients could benefit from this therapy”.

The Company will use their CHART-1 results as the foundation of their CHART-2 US trial, which will test the target patient group with C-CURE. Celyad is also in the process of seeking partnerships to accelerate further development and commercialization of C-Cure®.

Do C-CURE cells make new heart muscle cells?  Count me skeptical.,  Just because cells form something that looks like cardiac cells in culture is no indication that they form tried and true heart muscle cells.  This is especially true, since bone marrow-based cells lack the calcium handling machinery of heart muscle cells and until someone definitely shows that bone marrow cells can be transdiferentiated into cells that possess the calcium handling proteins of heart muscle cells, I will remain skeptical,

Having said that, this is a very interesting clinical trial despite the fact that it failed to meet its primary endpoints.  Further work might even make more of it.  Here’s to hoping.