Using Small Molecules to Covert Donated Stomach Cells into Stem Cells that Can Cure Liver Disease


A collaboration between Yunfang Wang from the Tissue Engineering Lab at the Beijing Institute of Transfusion Medicine in Beijing, China and Xuetao Pei, from the Stem Cell and Regenerative Medicine Lab, also at the Beijing Institute of Transfusion Medicine has produced a remarkable result.

Wang and Pei and their colleagues have used small molecules to convert human gastric epithelial cells into endodermal progenitors.  Endodermal stem/progenitor cells have diverse potential applications in research and regenerative medicine.  They can differentiate into just about any cell type in the gastrointestinal tract, including liver cells, and pancreatic cells.  Thus these cells may have a variety of uses in research, and perhaps even in the clinic.

In this experiment, gastric epithelial cells were isolated from human donors and cultured in the presence of a carpet of tissue-specific mesenchymal cells as support cells to help the gastric epithelial cells survive in primary culture.  These cells were then treated with a cocktail of small molecules that drove the cells to dedifferentiate into induced endodermal progenitor cells (hiEndoPCs). These cells can grow in culture, expand rapidly and express a variety of stem cell markers.

In culture, the hiEndoPCs were able to differentiate into liver cells (hepatocytes, pancreatic endocrine cells, and intestinal epithelial cells.  The differentiation protocols used in this paper all involved the use of small molecules – no genetic engineering of the cells was necessary.

Small molceules that convert gastric epithelial cells into hiEndoPCs

Then liver cells made from hiEndoPCs were transplanted into mice that had messed up livers (Fah -/- Rag2-/-).  Fah-mutant mice lack the enzyme fumarylacetoacetate hydrolase, and without this enzyme, the liver is incapable to processing toxic ammonium, which builds up in the liver and kills it.  Rag2 mutations prevent the mouse from rejecting implanted livers cells.  In these experiments, transplanted hepatocytes rescued liver failure in these mice.  hiEndoPCs had the added advantage of no causing teratomas, like embryonic stem cells.

Human gastric epithelial cells are easily isolated from human donors without causing harm to the donor.  They can be isolated from patients of a variety of ages and this strategy can easily convert those cells into a cell population that is readily expandable and can be personalized into cells from treating patients with abnormal livers, pancreases, or intestinal tracts.  This fascinating proof-of-principle paper brings such personalized medicine one step closer.

The article was published in Cell Stem Cells 2016, http://dx.doi.org/10.1016/j.stem.2016.06.006. 


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.

Bilateral, Multiple, Intraspinal Stem Cell Injections are Safe for ALS


Jonathan Glass, professor of neurology at Emory University in School of Medicine, is the principal investigator of a phase 2 clinical trial that examined the safety of intraspinal injection of human spinal cord–derived neural stem cells in people with amyotrophic lateral sclerosis (ALS), or Lou Gehrig’s disease.

This clinical trial was not designed to determine whether the treatment was effective, which is odd given that the trial was a phase 2 trial. Glass and his collaborators noted that the transplanted stem cells did not slow down the progression of the disease. However, given that the trial was not designed to detect efficacy, it is difficult to draw any hard-and-fast conclusions.

ALS is a disorder in which the motor neurons of the brain and spinal cord degenerate. Motor neuron degeneration causes progressive loss of muscle control, which includes breathing and swallowing (leading to death). There are no treatments that can stop ALS.

“Though there were two serious complications related to the treatment, the level of acceptable risk for treating patients with ALS, where the prognosis is poor and treatments are limited, is arguably higher than that for more benign disorders,” said Dr. Glass.

In this study, 15 ALS patients who manifested their first signs and symptoms of the disease within two years of the start of the study, were treated at three different university hospitals.

The participants were divided into five treatment groups that received increasing doses of stem cells. This trial was an “open-label” trial, which means that the participants knew they were getting active stem cell treatments.

Participants received bilateral (both sides) injections into the cervical spinal cord between the C3 and C5 regions. The final group received injections into both the lumbar (L2-L4) and cervical cord through two separate surgical procedures.

Vertebral Column regions

The numbers of injections ranged from 10 to 40, and the number of cells injected ranged from two million to 16 million. Because of the large range of injections and stem cells injected, determining the safety of these treatments was probably more important that the efficacy of the treatments.

During the nine months of follow-up, patients were assessed for side effects from the intraspinal injections and progression of the disease, according to the functional rating scale. Most of the side effects were related to temporary pain associated with surgery and to medications that suppress the immune system.

Two people developed serious complications related to the treatment. One patient developed spinal cord swelling that caused pain, sensory loss and partial paralysis, and another patient developed central pain syndrome; a neurological condition caused by damage to or dysfunction of the central nervous system (CNS), which includes the brain, brainstem, and spinal cord. This syndrome can be caused by stroke, multiple sclerosis, tumors, epilepsy, brain or spinal cord trauma, or Parkinson’s disease.

The participants’ functioning was compared to three historical control groups, and there was no difference in how fast the disease progressed between those
who received stem cells and those who did not. This is a significant finding because injecting cells into the spinal cord might actually accelerate the progression of the disease. However, this study seemed to show that 10-40 injections into the spinal do not affect the progression of ALS.

However, Glass cautioned that no conclusions can be draw about effectiveness of the treatment from such a small, non-blinded, non-placebo-controlled study.

“This study was not designed, nor was it large enough, to determine the effectiveness of slowing or stopping the progression of ALS. The importance of this study is that it will allow us to move forward to a larger trial specifically designed to test whether transplantation of human stem cells into the spinal cord will be a positive treatment for patients with ALS,” Dr. Glass said.

These results were published in Jonathan D. Glass et al., “Transplantation of spinal cord–derived neural stem cells for ALS: Analysis of phase 1 and 2 trials,” Neurology, June 2016 DOI:10.1212/WNL.0000000000002889.

Induced Pluripotent Stem Cells from Diabetic Foot Ulcer Fibroblasts


Dr. Jonathan Garlick is professor of Oral Pathology at Tufts University and has achieved some notoriety among stem cell scientists by publishing a stem-cell rap on You Tube to teach people about the importance of stem cells.

Garlick and his colleagues have published a landmark paper in the journal Cellular Reprogramming in which cells from diabetic patients were reprogrammed into induced pluripotent stem cells (iPSCs).

Garlick and his colleagues have established, for the first time, that skin cells from diabetic foot ulcers can be reprogrammed iPSCs. These cells can provide an excellent model system for diabetic wounds and may also used, in the future, to treat chronic wounds.

ESC and iPSCs differentiation to fibroblast fate. ESC and iPSC were differentiated and monitored at various stages of differentiation. Representative images show the morphology of ESC and 2 iPSC lines after days 1, 4, 7, 10, 14, 21 and 28 of differentiation. Early morphologic changes showed differentiation beginning at the periphery of colonies (day 1). At later stages cells acquired fibroblast features of elongated, stellate cells (day 10 at days 21 and 28 of differentiation.
ESC and iPSCs differentiation to fibroblast fate. ESC and iPSC were differentiated and monitored at various stages of differentiation. Representative images show the morphology of ESC and 2 iPSC lines after days 1, 4, 7, 10, 14, 21 and 28 of differentiation. Early morphologic changes showed differentiation beginning at the periphery of colonies (day 1). At later stages cells acquired fibroblast features of elongated, stellate cells (day 10 at days 21 and 28 of differentiation.

Garlick’s team at Tufts University School of Dental Medicine and the Sackler School of Graduate Biomedical Sciences at Tufts, have also used their diabetic-derived iPSCs to show that a protein called fibronectin is linked to a breakdown in the wound-healing process in cells from diabetic foot ulcers.

One of the goals of Garlick’s research is to develop efficient protocols to make functional cell types from iPSCs and to use them to generate 3D tissues that demonstrate a broad range of biological functions. His goal is to use the 3D model system to develop human therapies to replace or regenerate damaged human cells and tissues and restore their normal function.

In this paper, Garlick and his colleagues showed that not only can fibroblasts from diabetic wounds form iPSCs, but they can also participate in 3D skin-like tissues. This model system is more than a disease-in-a-dish system but disease-in-a-tissue system.

Fabrication of three-dimensional tissue construction. (A) A collagen gel embedded with human dermal fibroblasts is layered onto a polycarbonate membrane. (B) After dermal fibroblasts contract and remodel the collagen matrix, keratinocytes are then seeded onto it to create a monolayer that will form the basal layer of the tissue. (C) Tissues are raised to an air-liquid interface to initiate tissue development that mimics in vivo skin.
Fabrication of three-dimensional tissue construction. (A) A collagen gel embedded with human dermal fibroblasts is layered onto a polycarbonate membrane. (B) After dermal fibroblasts contract and remodel the collagen matrix, keratinocytes are then seeded onto it to create a monolayer that will form the basal layer of the tissue. (C) Tissues are raised to an air-liquid interface to initiate tissue development that mimics in vivo skin. From this site.

“The results are encouraging. Unlike cells taken from healthy human skin, cells taken from wounds that don’t heal – like diabetic foot ulcers – are difficult to grow and do not restore normal tissue function,” said Garlick. “By pushing these diabetic wound cells back to this earliest, embryonic stage of development, we have ‘rebooted’ them to a new starting point to hopefully make them into specific cell types that can heal wounds in patients suffering from such wounds.”

Scientists in Garlick’s laboratory used these 3D tissues to test the properties of cells from diabetic foot ulcers and found that cells from the ulcers get are not able to advance beyond synthesizing an immature scaffold made up predominantly of a protein called fibronectin.  Fibronectin, unfortunately, seems to prevent proper closure of wounds.

Fibronectin Sigma

Fibronectin has been shown to be abnormal in other diabetic complications, such as kidney disease, but this is the first study that directly connects it to cells taken from diabetic foot ulcers.

Deriving more effective therapies for foot ulcers has been slow going because of a lack of realistic wound-healing models that mimic the extracellular matrices of human tissues. This scaffolding is critical for wound repair in skin, and other tissue as well.

The work in this paper builds on earlier experiments that showed that cells from diabetic ulcers have fundamental defects that can be simulated using laboratory-grown 3D tissue models. These 3D models will almost certainly be a good model system to test new therapeutics that could improve wound healing and prevent those limb amputations that result when treatments fail.

Garlick’s 3D model will allow him and other researchers to push these studies forward. Can they differentiate their cells into more mature cell types that can be studied in 3D models to see if they will improve healing of chronic wounds?

More than 29 million Americans have diabetes. Diabetic foot ulcers, often resistant to treatment, are a major complication. The National Diabetes Statistics Report of 2014 stated that about 73,000 non-traumatic lower-limb amputations in 2010 were performed in adults aged 20 years or older with diagnosed diabetes, and approximately 60 percent of all non-traumatic lower-limb amputations occur in people with diabetes.

This paper appeared in: Behzad Gerami-Naini, et al., Cellular Reprogramming. June 2016, doi:10.1089/cell.2015.0087.

How Stem Cells Exit The Bloodstream


New research from a laboratory at North Carolina State University has changed our understanding of how therapeutic stem cells exit the bloodstream.  Understanding this new process, which has been given the name “angiopellosis” may not only increase our understanding of how intravenous stem cells home to their target tissues, but also how metastatic cancer cells invade new sites.

When white blood cells are summoned to a site of infection, they exit the bloodstream by means of a rather well understood process called “Leukocyte extravasation” or “diapedesis.”.

Leukocyte extravasation mostly occurs in post-capillary venules, where hemodynamic shear force are low.  This process is characterized by 4 steps: 1)  “chemoattraction;” 2)  “rolling adhesion;” 3) “tight adhesion;” and 4)  “(endothelial) transmigration.”. If any of these steps are inhibited, diapedesis does not occur.

White blood cells or leukocytes phagocytose or gobble up foreign particles, produce antibodies, secrete inflammatory response triggers (histamine and heparin), and neutralize histamine.  In general, leukocytes defend an organism and protect it from disease by promoting or inhibiting inflammatory responses. Leukocytes do most of their specific functions in tissues and they use the blood as a transport medium to reach the tissues of the body.

extravasation1319669430297

Below is a brief summary of each of the four steps involved in leukocyte extravasation:

1) Chemoattraction

Upon recognition of and activation by pathogenic organisms, resident macrophages in the affected tissue release small signaling proteins called “cytokines” such as IL-1, TNFα and chemokines (small molecules that induce cell migration). IL-1, TNFα and other blood-based  molecules induce the endothelial cells that line blood vessels near the site of infection to express cellular adhesion molecules, including selectins.  Circulating leukocytes are localized to the site of injury or infection as a result of secreted chemokines.

2) Rolling adhesion

Sugar residues on they surfaces of circulating leukocytes bind to these selectin molecules on the inner wall of the blood vessels.  This interaction, however, is relatively modest in its binding strength.  The sugar-selectin interaction causes the leukocytes to roll along the inner surface of the vessel wall as transient bounds are constantly broken and reformed between selectins and cell-bound sugars.

The carbohydrate binding partner for P-selectin, P-selectin glycoprotein ligand-1 (PSGL-1), is an expressed by different types of leukocytes. The binding of PSGL-1 on the leukocyte to P-selectin on the endothelial cell allows for the leukocyte to roll along the endothelial surface. This interaction can be fine-tuned by the different ways that sugars are attached to PSGL-1.   These different forms of PSGL-1 that have distinct patterns of sugar attachment have unique affinities for different selectins.  This gives different leukocytes varying abilities to migrate to distinct specific sites within the body.

3) Tight adhesion

The chemokines released by macrophages activate the rolling leukocytes and induce them to synthesize surface integrin molecules.   Integrin molecules create high-affinity associations between cells and bind tightly to complementary receptors expressed on endothelial cells. This immobilized the leukocytes, despite the shear forces of the ongoing blood flow.

4) Transmigration

The internal cytoskeleton of the leukocytes are reorganizes that the leukocytes spread out over the endothelial cells. In this form, leukocytes extend pseudopodia and pass through gaps between endothelial cells.  This migratory step requires the expression of PECAM proteins on both the surface  of the leukocytes and the endothelial cells.  PECAM interaction effectively pulls the cell through the endothelium. Once through the endothelium, the leukocyte must penetrate the underlying basement membrane.  The mechanism by which the leukocytes does this remains a source of some dispute.  Once in the interstitial fluid, leukocytes migrate along a gradient of attractant molecules towards the site of injury or infection.

When stem cells are administered intravenously, they too Havre a similar ability to leave the bloodstream, but the means by which they do so was poorly understood.

Ke Cheng and colleagues examined zebrafish and used genetically engineered fish whose blood vessels glowed a fluorescent color.  Next, these fish were injected with leukocytes, and stem cells from rats, humans, and dogs that had been labeled with a red fluorescent protein.  These cells were followed by means of time-lapsed, three-dimensional light sheet microscopic imaging.  This technology allowed Cheng and others to view the stem cells as they left the blood vessels.

As predicted, the leukocytes exited the bloodstream by means of leukocytes extravasation.  The stem cells, however, were actively expelled from the blood vessels by the endothelial cells.  The endothelial cells membranes moved around the stem cells, surrounded them, moved them through the endothelial cells and then extruded them on the opposite side of the blood vessel.  This is a very different process than diapedesis in which the leukocyte is the active participant.  In the case of the stem cells, the endothelial cells are the active participants and the stem cells passively exit the bloodstream.  Cheng and company called this process angiopellosis.

Other differences between angiopellosis and diapedesis involved the time of the process.  Diapedesis can occur rather quickly whereas angiopellosis takes hours.  During diapedesis, one cell moves at a time, but during angiopellosis, several cells are moved at a time.

How effective of a method is this to leave the bloodstream?  If cancer cells used angiopellosis to facilitate metastasis, cent we inhibit it?

Further work should answer these important questions.  This work was published in the journal Stem Cells, 2016; DOI:10.1002/stem.2451.

New Stem Cell Treatment for Bronchopleural Fistulas


Mayo Clinic researchers have made history by using a patient’s own stem cells to heal an open wound on the upper chest of a patient that had been caused by postoperative complications of lung removal.

A hole in the chest that opens to the outside is called a bronchopleural fistulae. Such wounds are holes that lead from large airways in the lungs to the membrane that lines the lungs.

Unfortunately, present treatments for bronchopulmonary fistulae tend to be terribly successful and death from such injuries are all too common.

According to Dr. Dennis Wigle, a Mayo Clinch Researcher, “Current management is not reliably successful. After exhausting therapeutic options, and with declining health of the patient, we moved toward a new approach. The protocol and approach were based on an ongoing trial investigating this method to treat anal fistulas in Cohn’s disease”.

So Dr. Wigle and his colleagues harvested stem cells from the belly fat of their patient and seeded onto a bioabsorbable mesh that was surgically implanted at the site of the fistula.

Follow-up imaging of the patient showed that the fistula had closed and remained healed. More than a year-and-a-half later, the patient remains asymptomatic and has been able to resume activities of daily living.

In their paper, Wigle and others describe their patient, a 63-year-old female patient, who was referred to Mayo Clinic for treatment of a large bronchopleural fistula.

Because present therapies offer little relief, Wigle and his team turned to regenerative therapies in order to try a more innovative treatment.

“To our knowledge, this case represents the first in human report of surgically placed stem cells to repair a large, multiple recurrent bronchopleural fistula. The approach was well tolerated suggesting the potential for expanded use,” said Dr. Wigle.

While this procedure was successful in this case, it is unclear if this treatment was the main contributor to the healing of the wound. Since this is a single-patient case study and not a double blinded, placebo-controlled study, it is lower-quality evidence.

However, Wigle and others hope to further examine this technique, and in particular, the use a patient’s own stem cells, to treat fistulae in the respiratory system.

This case study was published in Stem Cells Translational Medicine, June 2016 DOI:10.5966/sctm.2016-0078.

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.