NIH and Mesoblast Partner for Clinical Trial in End-Stage Heart Failure


Mesoblast Limited has partnered with the National Heart, Lung, and Blood Institute (a branch of the National Institutes of Health or NIH) to conduct a large clinical trial that uses Mesoblast’s proprietary adult stem cell treatment in patients with advanced heart failure that requires an implantable Left Ventricular Assist Device (LVAD) to maintain proper circulatory support. The Canadian Institutes for Health Research and the National Institute of Neurological Disease and Stroke are also supporters of this trial.

Mesoblast is an Australian company whose Mesenchymal Precursor Cells (MPCs) have shown some promise in several pre-clinical studies and a few small clinical trials. The main objective in this study is to use the MPCs in heart failure patients and to examine the ability of MPCs to reduce the need for LVADs. Also, the study will ascertain is MPCs reduce long-term complications of LVAD transplantation, the most common of which is repeated hospitalizations.

This 120-patient study, to be conducted by the NIH-funded Cardiovascular Surgical Trials Network, will evaluate the effects of MPC transplantation into the hearts of patients with advanced heart failure. 150 million MPCs will be injected into the hearts of each patient and this product is being tested as an “off-the-shelf” medical product.

This new clinical trial builds upon previous successful but small trials in which 30 heart patients were treated with either 25 million MPCs or MPC culture medium during LVAD implantation. This was a double-blind, placebo-controlled study, and it showed that the MPC-treated patients tended to show higher rates of not needing their LVADs anymore 90 days after implantation and 12 months after implantation. This study was complicated by the fact that several patients died during the trial, which is not surprising because patients who received LVADs tend to be very sick. Nevertheless, these results were suggestive that the MPCs were effective. This study was published in the journal Circulation, which is an American Heart Association publication.

This second study will examine 150 patients who will receive a higher dose of the MPCs and a phase three study is on the board in collaboration with Teva Pharmaceutical Industries Ltd, which is Mesoblast’s development and commercial partner, which will examine 1,700 patients.

One of the first measurements examined in this study is how long after the treatment until the patient experiences their first adverse heart event. These are called HF-MACEs or heart failure-related major adverse cardiac events. If MPCs delay the onset of the patient’s first HF-MACE, then the cells might be making the heart healthier and stronger.

Congestive heart failure is a chronic condition characterized by an enlarger heart and insufficient blood flow to the organs and extremities of the body. According to the American Heart Association, congestive heart failure affected ~5.1 million people 20 years of age or older in the US in 2010, and there are 825,000 new cases diagnosed annually. 50% of heart failure patients die within five years of diagnosis.

30%-40% of heart failure patients suffer from moderate/severe class II/III heart failure with low ejection fractions and 10% have advanced heart failure (NYHA class IV heart failure). the only treatment options for end-stage or class IV heart failure are a heart transplant or mechanical support with a LVAD. Heart transplants cannot meet the large need due to donor availability, and permanent LVAD support is currently limited by clinical complications.

Mesenchymal Stem Cells from Fat Relieve Arthritis Pain for Up to Two Years


Regeneus is an Australian regenerative that has developed an experimental treatment for arthritis called HiQCells.  HiQCell is a stem cell treatment made from the patient’s own adipose (fat) tissue, and is subsequently injected into an affected joint or tendon. Regeneus has tested their HiQCell treatment in an independent clinical study that examined the efficacy of injections of HiQCells into the joints of patients with osteoarthritis of the knee.  The study examined 40 patients with knee osteoarthritis.  Half of these patients received the placebo and half HiQCell in a double-blinded study.  When asked about their pain levels six months after the procedure, patients in the placebo and HiQCell group ~45% of patients reported less pain and by 12 months after treatment 55% of patients in both groups reported less pain.  Thus both treatments relieved pain to a similar degree.  However, when the progression of the disease was examined, a very different result was observed.  As osteoarthritis progresses, some of the breakdown products of joint cartilage appear in urine and blood.  By collecting urine and blood samples from osteoarthritis patients, the progression of the disease can be readily tracked.  Blood and urine testing showed significantly less cartilage breakdown in the HiQCell group and significantly more breakdown in the patients in the placebo group who had advanced cartilage damage. Thus, even though the patients who received placebo had about the same level of pain reduction over the six-month period, it seems that their cartilage breakdown progressed at a faster rate.

Now a follow-up examination of these and other subjects who participated in this initial clinical study has revealed something surprising.  According to Regeneus, as of July 21, 2014, from a collection of 386 patients: 1) Pain has continued to decrease two years post-treatment; 2) One year after treatment, 63 of 86 patients reported more than a 30% reduction in pain;
3) Two years after treatment, 14 of 17 patients reported more than a 30 % reduction in pain and 14 patients experienced an average pain reduction of 84% at two years post-treatment; 4) Patients also reported significant improvements from pre-treatment in knee-function, sleep quality and reduced pain medications.  Finally, it is clear from these results that HiQCell is a safe therapy and well tolerated by patients, since the frequency and severity of adverse effects of patients who received HiQCell treatments were no different from those received the placebo.

The HiQCell Joint Registry established by Regeneus is the first of its kind in that the patients who participate in this study are subjected to long-term follow-up and undergo stem cell therapy using the patient’s own fat-derived stem cells. The HiQCell study has been approved by a human research ethics committee.  These 386 patients included in the Joint Registry will continue to be followed for up to 5 years with analysis updated regularly.

Professor Graham Vesey, CEO of Regeneus, comments: “The registry data is demonstrating that HiQCell has a therapeutic benefit for longer than 2 years. We are now also beginning to see very encouraging data from patients that have had cells frozen for future injections. This combination of the long-term effect from HiQCell and the successful storage of cells for repeat injections in the future, means that HiQCell can be used to treat joint pain for many years. This is particularly important for patients that are too young for joint replacement or are simply looking to delay joint replacement.”

Mesenchymal Stem Cells Improve Movement and Decrease Neurodegeneration in Ataxic Mice


Friedrich’s ataxia (FA) results from insufficient concentrations of a protein called Frataxin.  Frataxin serves as an iron metabolism protein that puts iron into proteins that need it.  Because several proteins that play crucial roles in energy metabolism in cells use iron, Frataxin is a very busy molecule and without sufficient quantities of Frataxin, energy metabolism decreases and metabolically active cells, such as nerves and muscles, weaken and die.

Frataxin crystal structure.
Frataxin crystal structure.

In patients with FA, the dorsal root ganglia, which lie just in front of the spinal cord, are the first to die off and degenerate.  Can stem cell treatments provide relief from the ravages of FA?

DRG

To test this possibility, Salvador Martinez and his colleagues from the University Miguel Hernández in Alicante, Spain examined two mouse populations, both of which harbored loss-of-function mutations in the Frataxin (FXN) gene.  Mice from both groups were injected with bone marrow-derived mesenchymal stem cells isolated from either wild-type or YG8 mice.  YG8 mice a genetically manipulated so that they suffer from a mouse form of FA that shows several similarities to human FA.  The mesenchymal stem cells injections were “intrathecal” injections, which means that they were directly injected into the nervous system.

As a result of the stem cell injections,  both groups of mice showed improved motor skills compared to nontreated mice.  The dorsal root ganglia also showed increased frataxin expression in the treated groups, and less cell death.

Why did the stem cell-injected mice fare better?  Further investigations revealed that the injected mesenchymal stem cells expressed the following growth factors:  NT3, NT4, and BDNF.  All of these growth factors can bind to specific receptors embedded in the membranes of those sensory neurons located within the dorsal root ganglia and buck up their survival, thus preventing them from dying.  The stem cell-treated mice also had increased levels of “antioxidant enzymes.”. These are enzymes found in our own cells that dispose of dangerous molecules.  Enzymes such as catalase, superoxide dismutase and so on are examples of antioxidant enzymes.  The stem cell-treated mice had higher levels of catalase and GPX-1 in their dorsal root ganglia, which is significant because YG8 mice show decreased levels of these antioxidant enzymes.

Interestingly, the results were not significantly different if the injected stem cells were isolated from wild-type or YG8 mice. In both cases injected mesenchymal stem cells ameliorated the condition of the FA mice.

In conclusion, transplantation of bone marrow mesenchymal stem cells, either the patient’s own stem cells or donated stem cells, is a feasible therapeutic procedure that might delay the onset of cell death in the dorsal root ganglia of patients with Friedreich’s ataxia.

An Entire Organ Grown Inside an Animal


For the first time, scientists from Scotland have reported that an entire, functional organ has been grown from scratch inside a laboratory animal. A Scottish research group successfully transplanted a small quantity of cells into a laboratory mouse that grew and developed into a functional thymus.

These findings were published in the journal Nature Cell Biology, and might open the door to new alternatives to organ transplantation. This research certainly shows great promise, but is still years away from clinical trials and reproducible human therapies.

If you are wondering what the thymus is, it serves as an integral part of the immune system. The thymus is located just above and slightly over the heart and produces a vital component of the immune system, called T-cells, which fight infections and regulate the immune response.

The thymus
The thymus

thymus location

 

A research team from the Medical Research Council Centre for Regenerative Medicine at the University of Edinburgh began this experiment with mouse embryonic fibroblasts.  These fibroblasts are found in the skin and connective tissue of the embryo.  These mouse embryonic fibroblasts were genetically engineered to expressed the FOXN1 gene, which encodes a transcription factor known as the “forkhead box N1″ protein.  The forkhead box N1 protein binds to DNA and activates the expression of genes necessary to make thymic epithelial cells.  Mice that do not have a functional copy of the FOXN1 gene a “nude” mice.  They are nude because they have no hair and have no thymus.  

Once engineered to express FOXN1, the fibroblasts began to differentiate into thymic epithelial cells.  The Scottish team mixed these genetically engineered fibroblasts with some other support cells and transplanted them into laboratory mice where they summarily formed a fully functional thymus.  Structurally the animal-grown thymus contained the two main regions – the cortex and medulla – and it also produced T-cells.

Prof Clare Blackburn, who was part of the research team, said it was “tremendously exciting” when the team realized what they had accomplished.  Blackburn told the BBC: “This was a complete surprise to us, that we were really being able to generate a fully functional and fully organised organ starting with reprogrammed cells in really a very straightforward way.  This is a very exciting advance and it’s also very tantalising in terms of the wider field of regenerative medicine.”

Such a procedure could benefit patients who need a bone marrow transplant and children who are born without a functioning thymus.  Likewise because our immune response diminishes as we age and out thymus shrivels, such a procedure might boost the waning immune system of aged patients.   could all benefit from such a procedure.

However, there are a number of problems to solve before this procedure can cross the bridge from animal studies to hospital therapies.  First of all, the recipient of these implants were nude mice that had no thymus and could not reject transplanted tissue.  Also, the use of embryonic fibroblasts would cause a robust immune response against them.  Some other cell type must be found for this procedure that grows robustly and does not cause transplantation rejection.

Researchers also need to be sure that the transplant cells do not pose a cancer risk by growing uncontrollably.  Prof Robin Lovell-Badge, from the National Institute for Medical Research, said: “This appears to be an excellent study.  This is an important achievement both for demonstrating how to make an organ, albeit a relatively simple one, and because of the critical role of the thymus in developing a proper functioning immune system.  However… the methods are unlikely to be easy to translate to human patients.”

This experiment is a testimony of just how far the field of regenerative medicine has come.  Already patients with lab-grown blood vessels, windpipes and bladders have benefited from advances in regenerative medicine. These tissue engineered structures have been made by “seeding” a patient’s cells into a scaffold which is then implanted.  The thymus in this case only required one injection of a cluster of cells.  While it is doubtful that other organs will be this easy to grow, it is an encouraging start.

Also, this experiment utilized “direct reprogramming” that did not require taking cells through the embryonic stage.  Instead one-gene reprogramming directed the cells to make thymus epithelium cells.  This almost certainly promises to be a much safer way to make cells for regenerative treatments.

Dr Paolo de Coppi, who pioneers regenerative therapies at Great Ormond Street Hospital, said: “Research such as this demonstrates that organ engineering could, in the future, be a substitute for transplantation.  Engineering of relatively simple organs has already been adopted for a small number of patients and it is possible that within the next five years more complex organs will be engineered for patients using specialised cells derived from stem cells in a similar way as outlined in this paper.  It remains to be seen whether, in the long-term, cells generated using direct reprogramming will be able to maintain their specialised form and avoid problems such as tumour formation.”

Accelerating Bone Regeneration with Combination Gene Therapy and Novel Scaffolds


A truly remarkable paper in the journal Advanced Healthcare Materials by Fergal J. O’Brien and his co-workers from the Tissue Engineering Research Group at the Royal College of Surgeons in Dublin, Ireland has examined a unique way to greatly speed up bone regeneration.

Mesenchymal stem cells from bone marrow (other locations as well) can differentiate into bone-making cells (osteoblasts) that will make architecturally normal bone under particular conditions. The use of mesenchymal stem cells and a variety of manufactured biomaterial matrices and administered growth factors enhance bone formation by mesenchymal stem cells (M. Noelle Knight and Kurt D. Hankenson, Adv Wound Care 2013; 2(6): 306–316; also see Marx RE, Harrell DB. Int J Oral Maxillofac Implants 2014 29(2)e201-9; and Kaigler D, et al., Cell Transplant 2013;22(5):767-77).

Protein growth factors tend to have rather short half-lives when applied to growth scaffolds. A better way to apply growth factors is to use the genes for these growth factors and apply them to “gene activated scaffolds.” Gene-activated scaffolds consist of biomaterial scaffolds modified to act as depots for gene delivery while simultaneously offering structural support and a matrix for new tissue deposition. A gene-activated scaffold can therefore induce the body’s own cells to steadily produce specific proteins providing a much more efficient alternative.

In this paper by O’Brien and his groups, the genes for two growth factors, VEGF and BMP2, were applied to a gene-activated scaffold that consisted of collagen-nanohydroxyapatite. VEGF drives the formation of new blood vessels, and this fresh vascularization, coupled with increase bone deposition, which is induced by BMP2, accelerated bone repair.

Mind you, the assays in the paper were conducted in cell culture systems. However, O’Brien and his colleagues implanted these gene-activated scaffolds with their mesenchymal stem cells into rats that had large gaps in their skulls. In this animal model system for bone repair, stem cell-mediated bone production, in addition to increased blood vessel formation accelerated bone repair in these animals. Tissue examinations of the newly-formed bone showed that bone made from gene-activated scaffolds with mesenchymal stem cells embedded in them made thicker, more vascularized bone than the other types of strategies.

This is not a clinical trial, but this preclinical trial shows that vascularization and bone repair by host cells is enhanced by the use of nanohydroxyapatite vectors to deliver a combination of genes, thus markedly enhancing bone healing.

Mesenchymal Stem Cells Derived from Induced Pluripotent Stem Cells are Epigenetically Rejuvenated


Earlier this year, Miltalipov and his research group published a paper in Nature that compared the genetic integrity of embryonic stem cells made from embryos, to induced pluripotent stem cells and embryonic stem cells made from cloned embryos.  All three sets of stem cells seemed to have comparable numbers of mutations, but the induced pluripotent stem cells had “epigenetic changes” that were not found in either stem cell line from cloned or non-cloned embryos.

Genetic characteristics have to do with the sequence of the DNA molecules that make up the genome of an organism.  Epigenetic characteristics have nothing to do with the sequence of DNA, but instead are the result of small chemicals that are attached to the DNA molecule.  These small chemical tags affect gene expression patterns.  Every cell has a specific epigenetic signature.

During development, the cells that will form our eggs and sperm in our bodies, the “primordial germ cells,” begin their lives in the outer layer of the embryo.  During the third week of life, these primordial germ cells or PGCs move like amoebas and wander into the yolk sac wall and collect near the exit of a sac called the “allantois.”  The PGCs are outside the embryo at this time or extraembryonal.  Incidentallyyolk sac is a terrible name for this structure, since it does not produce yolk proteins.  Therefore other textbooks have renamed it the “primary umbilical vesicle,” which is a bit of a mouthful, but it probably better than “yolk sac.”

 

1 - Primordial germ cells 2 - Allantois 3 - Rectum 4 - Ectoderm 5 - Foregut 6 - Primordial Heart 7 - Secondary yolk sac 8 - Endoderm 9 - Mesoderm 10 - Amniotic cavity
1 – Primordial germ cells
2 – Allantois
3 – Rectum
4 – Ectoderm
5 – Foregut
6 – Primordial Heart
7 – Secondary yolk sac
8 – Endoderm
9 – Mesoderm
10 – Amniotic cavity

The embryo around this time undergoes a bending process as a result of its growth and the head bends toward the tail (known as the cranio-caudal curvature) and then the sides of the embryo fold downwards and eventually fuse (lateral folding).  This bending of the embryo allows the PGCs to wander back into the embryo again between the fourth and sixth week.  The PGCs move along the yolk sac wall to the vitelline and into the wall of the rectum.  After crossing the dorsal mesentery (which holds the developing intestines in place) they colonize the gonadal or genital ridge (which is the developing gonad). During their journey, and while in the gonadal ridge, the PGCs divide many times.

1 - Rectum 2 - Vitelline 3 - Allantois 4 - Nephrogenic cord (pink) 5 - Gonadal ridge (green) 6 - Primordial germ cells (red dots) 7 - Heart prominence
1 – Rectum
2 – Vitelline
3 – Allantois
4 – Nephrogenic cord (pink)
5 – Gonadal ridge (green)
6 – Primordial germ cells (red dots)
7 – Heart prominence

When the PGCs move into the developing gonad, the chemical tags on their DNA are completely removed (rather famous paper – Lee, et al., Development 129, 1807–1817 (2002).  This epigenetic erasure proceeds in order for the PGCs to develop into gametes and then received a gamete-specific set of epigenetic modifications.  These epigenetic modifications also extend to the proteins that package the DNA into chromosomes – proteins called histones.  Specific modifications of histone proteins and DNA lead to gamete-specific expression of genes.  Once fertilization occurs, and the embryological program is initiated, tissue-specific epigenetic modifications are conveyed onto the DNA and histones of particular cell populations.

This is a long-winded explanation, but because many cancer cells have abnormal epigenetic modifications, these epigenetic abnormalities in induced pluripotent stem cells (iPSCs) have been taken with some degree of seriousness.  Although, there is little evidence to date that links the cancer-causing capabilities of iPSCs with specific epigenetic modifications, although it certainly affects the ability of these cells to differentiate into various cell types.

A paper has just come from the laboratory of Wolfgang Wagner from the Aachen University Medical School, in Aachen, Germany that derived iPSCs from mesenchymal stem cells from human bone marrow, and then in a cool one-step procedure, differentiated these cells into mesenchymal stem cells (MSCs).  These  iPS-MSCs looked the same, and acted the same in cell culture as the parent MSCs, and had the same gene expression profiles as primary MSCs.  However, all age-related and tissue-specific epigenetic patterns had been erased by the reprogramming process.  This means that all the tissue-specific, senescence-associated, and age-related epigenetic patterns were erased during reprogramming.  Another feature of these iPS-MSCs is that they lacked but the ability to down-regulate the immune response, which is a major feature of MSCs.

Thus, this paper by the Wagner lab shows that MSCs derived from iPSCs are rejuvenated by the reprogramming process.  Also, the donor-specific epigenetic features are maintained, which was also discovered by Shao and others last year.  This suggests that epigenetic abnormalities are not an inherent property of the derivation of iPSCs, and that this feature is not an intractable characteristic of iPSCs derivation and may not prevent these cells from being successfully and safely used in the clinic.  However, this might be a cell type-specific phenomenon.  Also, the loss of the immune system regulatory capabilities of these iPS-MSCs is troubling and this requires further work.

iPS-MSCs

3D Printed Facial Implant Approved by the FDA


Three-dimensional printing uses modified ink-jet printers to spray cells and biomaterials into shapes that mimic human organs, tissues and structures. These three-dimensional printers have been used to make a variety of implantable structures.

Last year, Oxford Performance Materials announced that they had successfully created a 3D-printed implant that could replace 75 percent of a patient’s skull. This OsteoFab Patient Specific Cranial Device was made of PEKK (Polyetherketoneketone) biomedical polymer and was printed by using CAD files that had been developed to personally fit each patient’s specific dimensions. PEKK is an ultra high performance polymer used in biomedical implants and other highly demanding applications. The PEKK polymer has the advantage of being biomechanically similar to bone. The Osteofab skull implant was approved by the FDA in February of 2013.

Osteofab

The success of OsteoFab laid the groundwork for the recent FDA approval of Oxford’s OsteoFab Patient-Specific Facial Device, a customizable implant for facial reconstruction.

ORM 3D printed facial implant

Implants like this are known as “biocompatible implants,” which behave mechanically, in this case, like real bone.  The techniques developed by Oxford Performance Materials allow engineers to fabricate pieces that match an individual patient’s specific facial dimensions and structure in a manner that reduces the overall cost of the procedures required to surgically reconstruct a face after devastating injury. Due to these technical advances pioneered by Oxford Performance Materials, facial implants can be fabricated very quickly, which allows the plastic surgeons to get the patient into surgery sooner rather than later.

“With the clearance of our 3D printed facial device, we now have the ability to treat these extremely complex cases in a highly effective and economical way, printing patient-specific maxillofacial implants from individualized MRI or CT digital image files from the surgeon,” said Scott DeFelice, CEO of Oxford Performance Materials, in a statement. “This is a classic example of a paradigm shift in which technology advances to meet both the patient’s needs and the cost realities of the overall healthcare system.”

Oxford’s 3D-printed Osteofab cranial implants also have FDA approval and could potentially be combined with these facial implants into a single device for treating severe cases.  Although these facial implants have not yet been used in the United States, Oxford said the implants are now available to doctors and hospitals.

From artificial fingertips to airway splints that help babies breathe, 3D printing has provided the means to address complex surgical repairs.  The good news is that skull caps and facial bones are just the beginning of what 3D printing technologies can achieve.  We may soon see FDA approval for other bones, like knee caps, hips, and even small bones in the fingers and hands.

It’s all a part of a growing wave that could make 3D printers just as common as MRI machines in the tool kits used by physicians to repair and heal injured people.

Chicken Induced Plurpotent Stem Cells Made With Minicircles


The safety of induced pluripotent stem cells (iPSCs) haws been debated in several studies and publications.  Original studies of the genetic differences between the cellular sources of iPSCs and the iPSCs derived from them tended to show a whole gaggle of new mutations that seemed to not appear in the original cells.  Therefore, several commentators warned about the “dark side of pluripotency.”. However, other studies that utilized higher-resolution techniques showers that many of these mutations that occurred in iPSCs did exist in the original cells before their reprogramming, but that these mutations occurred at low frequencies, but became amplified during the culturing of reprogrammed cells.

One feature that has received less attention in these discussions of the safety of iPSC derivation is that the method by which iPSCs are made has distinct consequences for the stem cells that are made.  Typically, methods that utilize gene vectors that do not integrate into the genomes of the host cells are inherently safer than those vectors that do integrate.  PiggyBac transposon vectors integrate, but self-excise soon after their integration, and, therefore, do not leave a trace or their previous integration.  Minicircles also do not integrate and tend to produce safer iPSCs.  For this reason, this present paper is of interest to us.

Franklin West and his colleagues at the University of Georgia have made chicken iPSCs using minicircles to reprogram adult cells.  West was interested in using iPSCs to make recombinant chickens, since chickens are a rather primary food source and major component of economic development in several countries.  Making transgenic or recombinant chickens by means of stem cell technology makes it possible to make animals with improved meat and egg production or disease resistance.

To this end, West and his group made chicken (c) iPSCs from skin fibroblast cells by means of a nonviral minicircle reprogramming method.  This resulted in ciPSCs that showed excellent stem cell appearance and expressed key stem cell marker genes (alkaline phosphatase, POU5F1, SOX2, NANOG, and SSEA-1).  These cells also showed very rapid growth in culture and expressed high levels of the enzyme telomerase, which is an enzyme that is vital for the maintenance of chromosomes.

When West and his research group transplanted late-passage ciPSCs into stage X chicken embryos, the cIPSCs successfully integrated into the growing embryo and contributed to tissues derived from all three primary germ layers (ectoderm, mesoderm, and endoderm).  These ciPSCs also contributed to the gonads, which means that the ciPSCs could make gametes that could contribute to the production of a new generation of chicken.

These ciPSCs provide an exciting new tool to create transgenic chickens and has broad and exciting implications for agricultural and transgenic animal fields at large.  However, it also demonstrates that iPSCs can be safely produced and used for agricultural purposes.  This means that if non-integration-based or non-viral-based techniques are used to make iPSCs it should be possible to make them safely for therapeutic purposes also.

Kyoto University Scientist Plans iPSC Clinical Trial for Parkinson’s Disease Patients


According to the Japan Times, Kyoto University’s Jun Takahashi and his team have plans to launch a clinical study for Parkinson’ disease patients that will utilize cells derived from induced pluripotent stem cells made from the patient’s own cells.

In an interview with Takahashi, the Japan Times reported on Wednesday of this week that he hopes to develop the induced Pluripotent Stem Cell (iPSCs) treatment as soon as possible so that Kyoto University Hospital can provide this treatment by fiscal year 2018 as a designated advanced medical technique that can be used in combination with other conventional treatments and medicines already covered by various insurance policies. Takahashi also expressed his hope that by fiscal year 2023, public health insurance will pay for his treatment.

For this clinical study, Parkinson’s disease patients whose conditions have progressed to the point where their medications are no longer effective will be the primary targeted group.  “It will take a long time” to establish an effective treatment for the progressive disorder, which is incurable at present, Takahashi said, stressing the importance of maintaining a positive attitude toward development and not losing hope.

Parkinson’s disease causes the nerve cells in the brain that utilize the neurotransmitter dopamine to die off.  The death of these dopaminergic neurons adversely affects voluntary muscle movement.

The design of this clinical study will include the production of iPSCs from adult cells collected from participating patients.  These stem cells will be differentiated into neural stem cells that make dopaminergic neurons.  These dopaminergic neuron precursor cells will be transplanted back into the midbrains of the donors before they develop into nerve cells, according to Takahashi.  This way, all injected cells will still have the capacity to divide and migrate once implanted into the brain, but they will still have the capacity to form dopaminergic neurons.

Takahashi’s team will also seek to develop a method for producing a nerve cell drug created from cells taken out of healthy people, to ease the financial burden on patients, he said, since the derivation of iPSCs remains prohibitively expensive.

Takahashi also said he aims to being clinical trials by March 2019.

Regenerating Tooth Roots With Biomaterials


Several different types of stem cells can regenerate tooth enamel, but regenerating the tooth root has proven quite difficult.

Structure_of_Tooth

As you can see from the image above, the tooth root is covered with a tough, fibrous covering called the cementum.  The cementum connects the tooth root to the alveolar bone of the upper and low jaw by means of the periodontal membrane.  the cementum is a thin layer of bone-like material that covers the roots.  It is yellowish and softer than either dentine or enamel.  It is made by a layer of cementum-producing cells called cementoblasts that are adjacent to the dentine.  The periodontal ligament is cellular and its fibers hold the tooth in its socket, which are embedded in the cementum, as shown in the micrograph below.  The complexity of this structure shows you why regenerating this structure is so difficult.

Cementum-peridontal ligament

Howwever, a new study from the laboratory of Weihua Guo at Sichuan University, China has shown that platelet-rich fibrin (PRF) and treated dentin matrix (TDM) can concentrate a variety of various growth factors that summon native stem cells to them, and induce them to regenerate the tooth root.

Guo’s laboratory examined the ability of PRF and TDM to summon endogenous stem cells to the site of an extracted tooth in order to initiate regeneration of the tooth root.  Tooth roots contain soft and hard periodontal tissues, and if periodontal ligament stem cells (PDLSCs) and bone marrow mesenchymal stem cells (BMSCs) could be recruited to the site of tooth extraction by PRF and TDM, then maybe they could initiate tooth root regeneration.

Beagles were used as a transplantation model for this experiment.  After tooth extraction PRF and TDM implants were embedded in the tooth socket.  Also, these matrices were examined in cell culture with  PDLSCs and BMSCs.

PRF significantly recruited and stimulated the growth of both PDLSCs and BMSCs in culture.  In combination, PRF and TDM induced cell differentiation of these implanted stem cell populations.  PRF and TDM induced the expression of mineralization-related genes, such as bone sialoprotein (BSP) and osteopotin (OPN) after only one week in culture.

When implanted into the tooth sockets of beagles that had teeth extracted, transplantation platelet-rich fibrin made from the dog’s own blood products, and TDM made from other animals into fresh tooth extraction socket successfully regenerated the tooth root 3 months after the surgery.  The cementum and periodontal ligament (PDL)-like tissues with properly orientated fibers were clearly present, and the presence of these structures is indicative of functional restoration.

These results suggest that tooth root and the connection of the tooth root to the alveolar bone by cementum and peridontal ligaments can be effectively regenerated through the implantation of PRF and TDM in a tooth socket.  It seems to achieve this regeneration by summoning BMSCs and PDLSCs.  These cues provided by these matrices and the microenvironment provided by the tooth socket are key factors for this regeneration. This strategy provides a genuine clinical pathway toward tooth root regeneration in human patients with destroying human embryos.

A Genetic Recipe To Convert Stem Cells into Blood


University of Wisconsin at Madison Stem Cell researchers led by Igor Slukvin discovered two genetic programs that can convert pluripotent stem cells into the wide array of white and red blood cells found in human blood (pluripotent means “capable of developing into more than one organ or tissue and not fixed as to potential development).

This research has ferreted out the actual pathway used by the developing human body to make blood-based cells at the early stages of development.

During embryonic development, blood formation, which includes the formation of blood cells and blood vessels from the same progenitor cell; a cell called a hemangioblast. This begins in week three of development in the extraembryonic mesoderm or the primary embryonic umbilical sac, which is also known as the yolk sac. Also, the connecting stalk and chorion contain blood islands as well. These blood islands are rich in particular growth factors such as vascular endothelial growth factor (VEGF) and placental growth factor (PIGF). The blood islands form clusters with two cell populations; peripheral cells (angioblasts) that form the endothelial cells that form vessels. These networks of vessels extend and fuse together to form a robust a network. The cores of the blood islands (hemocytoblasts) form blood cells. Initially all vessels (arteries and veins) look the same. Blood formation occurs later in week 5, and occurs throughout the embryonic mesenchyme (connective tissue), and then moves to the liver, and then the spleen, and then bone marrow.

Embryonic red blood cells
Embryonic red blood cells

Hematopoietic stem cells (HSCs), the stem cells that form the blood cells, form from the wall of the aorta, which is the major blood vessel in the embryo. In the aortic wall, cells called hemogenic endothelial cells bud off progenitor cells that become HSCs.

A course of transcription factors have now been identified by Slukvin and his team as the triggers that switch these cells into HSCs. Two groups of transcriptional regulators can induce distinct developmental programs from pluripotent stem cells. The first developmental program, directed by the transcription factors ETV2 and ​GATA2, the pan-myeloid pathway, switches cells into the myeloid lineage (the myeloid lineage includes red blood cells, platelets, neutrophils, macrophages, basophils and eosinophils). The second developmental pathway, directed by the transcription factors GATA2 and ​TAL1, directs cells into the erythro-megakaryocytic pathway. In either cases, these transcription factors directly convert human pluripotent stem cells into an endothelium, which subsequently transform into blood cells with pan-myeloid or erythro-megakaryocytic potential.

Hematopoietic_and_stromal_cell_differentiation

In Slukvin’s laboratory, treatment of either ETV2 and ​GATA2 or GATA2 and ​TAL1 induced cells to make the complete range of human blood cells. Slukvin said of these experiments, “This is the first demonstration of the production of different kinds of cells from human pluripotent stem cells using transcription factors.” Transcription factors bind to DNA at specific sites and regulate gene expression.

Slukvin continued: “By overexpressing just two transcription factors, we can, in the laboratory dish, reproduce the sequence of events we see in the embryo.”

Slukvin and his co-workers showed that his technique produced blood cells by the millions. For every million stem cells, it was possible to produce 30 million blood cells.

Slukvin and his colleagues did not use viruses to genetically modify these stem cells. Instead they used modified RNA to induce overexpression of these transcription factors. Such a technique avoids genetic modification of cells and is inherently safer.

“You can do it without a virus, and genome integrity is not affected,” said Slukvin.  This technique might also work to differentiate pluripotent stem cells into other cell types, such as pancreatic beta cells, brain-specific cells, or liver cells.

Despite these successes, Slukvin says that the “Holy grail” of hematopoietic research is to differentiate pluripotent stem cells into HSCs.  Since HSC transplants are used to treat multiple myeloma and other types of blood-based cancers as well, making HSCs in the laboratory remains a significant goal and challenge as well.

“We still don’t know how to do that,” said Slukin, “but our new approach to making blood cells will give us an opportunity to model their development in a dish and identify novel hematopoietic stem cell factors.”

High-Dose Stem Cell Treatments in Chronic Heart Patients Increases Survival Rates


The DanCell clinical trial was conducted about seven years ago at the Odense University Hospital, Odense, Denmark by a clinical research team led by Axel Diederichsen. The DanCell study examined 32 patients with severe ischemic heart failure who had received two rounds of bone marrow stem cell treatments.

The DanCell study was small and uncontrolled. However, because the vast majority of stem cell-based clinical trials have examined the efficacy of stem cell treatments in patients who have recently experienced a heart attack, this study was one of the few that examined patients with chronic heart failure.

In this study, patients had an average ejection fraction of 33 ± 9%, which is in the cellar – normal ejection fractions in healthy patients are in the 50s-60s. Therefore, these are patients with distinctly “bad tickers.” All 32 patients received two repeated infusions (4 months apart) of their own bone marrow stem cells, but these stem cell infusions were quantitated to determine the number of “CD34+” cells and the number of “CD133+” cells. CD34 is a cell surface protein found on bone marrow hematopoietic stem cells, but it by no means exclusive to HSCs. CD133 is also a cell surface protein found, although not exclusively, on the surfaces of cells that form blood vessels and blood vessels cells as well.

Initially, patients showed no improvements in heart function after 12 months. However, when patients were classified according to those who received the most or the least number of CD34+ cells, a curious thing emerged: those who received more CD34+ cells had a better chance of surviving than those who received fewer CD34+ cells.

Is this a fluke? To determine if it was, Diederichsen and his colleagues followed these patients for 7 years after the bone marrow infusion. When Diederichsen and his colleague recorded the number of deaths and compared them with the number of CD34+ cells infused, the pattern once again held true. The CD34+ cell count and CD133+ cell count did not significantly correlate with survival, but the CD34+ cell count alone was significantly associated with survival. In the authors own words: “decreasing the injected CD34 cell count by 10[6] increases the mortality risk by 10%.”

The conclusions of this small and admittedly uncontrolled study: “patients might benefit from intracoronary stem cell injections in terms of long-term clinical outcome.”

Three things to consider: Patients with heart conditions have poorer quality bone marrow stem cell numbers. Therefore, allogeneic stem cells might be a better way to go with this patient group. Secondly, the Danish group used Lymphoprep to prepare their bone marrow stem cells, which has been used in other failed studies, and the stem cell quality was almost certainly an issue in these cases (see the heart chapter in my book The Stem Cell Epistles for more information). Therefore, independent tests of the bone marrow quality are probably necessary as well or a different isolation technique in general. Also, a controlled trial must be run in order to confirm the efficacy of bone marrow stem cell infusions for patients with chronic ischemic heart disease. Until them, all we can conclude is that intracoronary injections of a high number of CD34+ cells may have a beneficial effect on chronic ischemic heart failure in terms of long-term survival.

Bone Marrow or Umbilical Cord Stem Cells Treat Refractory Lupus-Related Kidney Disease


Autoimmune diseases are those diseases in which the patient’s own immune system attacks his or her own tissues. the treatment of such diseases requires giving patients drugs that suppress the immune system. Such drugs have potent side effects and taking such drugs long-term can also predispose patients to cancers and other types of inimical conditions.

One particular type of autoimmune disease, Systemic Lupus Erythematosis, otherwise known as SLE or just Lupus, results from an immune response against components inside our cells. The recognition of these proteins and other substances by our immune system causes massive cell damage and death. However, lupus is a very individual disease. In some patients, the disease manifests by producing butterfly-like lesions on the face.

Lupus butterfly rash (from http://emedicine.medscape.com/article/332244-overview)
Lupus butterfly rash (from http://emedicine.medscape.com/article/332244-overview)

In others, a severe arthritis in several joints results. In other lupus patients, the liver undergoes progressive degradation and scarring. Still others have severe heart problems, and others have scarring and progressive damage to the kidneys. In other patients a combination of symptoms and organs are affected. Some cases of lupus are sporadic and mild, but others are fulminant and relentless. The particular disease a person shows is completely individual.

In some lupus patients, the kidneys experience lupus nephritis (LN), which is inflammation of the tissues of the kidney. In some patients, drug treatments with corticosteroid drugs like prednisone, or other drugs like hydroxychloroquine (Plaquenil), also can help control lupus. Other drugs include powerful immune suppressants such as cyclophosphamide (Cytoxan), azathioprine (Imuran, Azasan), mycophenolate (Cellcept), leflunomide (Arava) and methotrexate (Trexall), all of which have lists of side effects that include increased risk of infection, liver damage, decreased fertility and an increased risk of cancer. However in a percentage of LN patients, drug treatments simply do not work, and these conditions are known as refractory LN.

A new clinical trial has examined the ability of mesenchymal stem cells from bone marrow or umbilical cord tissue to treat refractory LN. This Chinese study examined 81 patients with active refractory LN. The mesenchymal stem cells (MSCs) used in this study were “allogeneic,” which means that they were taken from someone other than the patient. Such treatments have been shown to successfully treat patients with other types of autoimmune diseases (see Figueroa FE, et al., Biol Res. 2012;45(3):269-77).

In this single-center clinical trial, Fei Gu and Dandan Wang and others from the Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing, Jiangsu, China enrolled 81 Chinese patients with active and refractory LN from 2007 to 2010. These patients received by intravenous administration either allogeneic bone marrow- or umbilical cord-derived MSCs at a dose of 1 million cells per kilogram of bodyweight. All 81 patients were then monitored over the course of one year with periodic follow-up visits to evaluate kidney function and to determine if the patients were experiencing any adverse events from the stem cell treatments.

During the year-long follow-up, 77 of the 81 patients survived ( survival rate of 95%) and 49/81 patients (60.5%) achieved remission. Eleven of 49 (22.4 %) patients showed a “renal flare,” which means that their symptoms and kidney inflammation returned by the end of 12 months after having previously experienced complete remission.

Kidney function jumped during this time. The main measure of kidney function is a test called the glomerular filtration rate or GFR. This measures how well the kidney filters materials per unit time. GFR in these patients improved significantly 12 months after the stem cell treatment (mean ± SD, from 58.55 ± 19.16 to 69.51 ± 27.93 mL/min). Two other measures used to determine the severity of lupus in a patient (Systemic Lupus Erythematosus Disease Activity Index or SLEDAI score), and the activity of lupus within the kidney (British Isles Lupus Assessment Group or BILAG scores) also decreased consistently, showing that the severity of the disease decreased and the severity of the disease within the kidney also decreased after the stem cell treatment (BILAG scores – 4.48 ± 2.60 at baseline to 1.09 ± 0.83 at 12 month and the SLEDAI scores – 13.11 ± 4.20 at baseline to 5.48 ± 2.77 at 12 months).

If that is not convincing, get this: the doses of prednisone and immunosuppressive drugs required by these patients were tapered. In other words, patients were able to eventually get off their drugs sometime within this year-long period. Is that cool or what!! No transplantation-related adverse events were observed.

Thus, the authors conclude, “Allogeneic MSCT resulted in renal remission for active LN patients within 12-month visit, confirming its use as a potential therapy for refractory LN.”

Now this treatment is NOT a cure. Several patients still experienced renal flares one year after treatment, and not all the patients experienced remission. Therefore, this is not a treatment for everyone. Identifying which patients will be helped by these treatments might require microarray analyses, but the bottom line is clear – some patients are definitely helped by MSC treatments.

Granted this is a small study and it is not a controlled study – these stem cell-treated patients were not compared to anything else. However it is a very hopeful beginning. There were no adverse side effects and 60% of the patients experienced remission, and that is definitely good news

Correcting Mutations Associated with a Blood Disorder


The protein hemoglobin carries oxygen from our lungs to our tissues. Mutations in the genes that encode the protein chains that form hemoglobin can cause inherited blood disorders like sickle-cell anemia, or the so-called Thalassemias. Thalassemias come from the Greek word from sea (θάλασσα or thalassa), because these blood disorders are found in Mediterranean populations. Thalassemias are found in these populations because they convey some resistance to malaria, which was endemic to that area. People with thalassemias tend to have fatigue, weakness, a pale appearance, yellow discoloration of skin (jaundice), facial bone deformities, slow growth, abdominal swelling, or dark urine, although some people have no symptoms.

Now this common genetic blood disorder has been genetically corrected in cultured induced pluripotent stem cells by using cutting-edge genome-editing techniques.

β-Thalassaemia shows reduced levels of hemoglobin, and these reduced levels are due to mutations in the gene that encodes the β-globin protein. Hemoglobin consists of four protein chains, two of which are alpha-globin proteins, and the other two of which are beta-globin proteins. Mutations in the beta-globin gene reduces the levels of functional beta-globin protein and this reduces the levels of functional hemoglobin.

Yuet Kan and his colleagues at the University of California, San Francisco, made induced pluripotent stem cells from skin fibroblasts from a person who suffered from β-thalassemia. Kan and his colleagues then used the CRISPR–Cas9 gene-editing technique to correct the mutation responsible for β-thalassemia. The CRISPR–Cas9 gene-editing technique allows for precise and accurate correction of the mutation without affecting other genes.

After the genetic editing, the iPSCs were differentiated into the precursors of red blood cells in culture and demonstrated that the modified cells showed higher expression of hemoglobin than unmodified cells.

Hopefully transplantation of such corrected cells back into the original patient could one day provide a cure for β-thalassaemia, according to the authors.

One Step Closer To Stem Cell Treatment for Multiple Sclerosis


Valentina Fossati and her colleague Panagiotis Douvaras from the New York Stem Cell Foundation (NYSCF) Research Institute have brought us one step closer to creating a viable stem cell-based therapy for multiple sclerosis from a patient’s own cells.

Valentina Fossati, Ph.D.
Valentina Fossati, Ph.D.

NYSCF scientists have, for the first time, produced induced pluripotent stem cell (iPSCs) lines from skin samples of patients who suffer from primary progressive multiple sclerosis. Fossati, Douvaras and colleagues also developed an accelerated protocol to differentiate iPSCs into oligodendrocytes, which are the myelin-making cells that insulate axons of central nervous system neurons. Destruction of the insulating myelin sheath is one of the hallmarks of multiple sclerosis, and oligodendrocyte progenitor cells or OPCs can replace damaged myelin sheath material.

Previously, producing oligodendrocytes from pluripotent stem cells required almost half a year to produce, which limited research on these cells and the development of treatments. This present study, however, has reduced the time required to make oligodendrocytes by half. This increases the feasibility of making these cells and using them in research and, potentially, for treatments.

Oligodendrocytes

By making oligodendrocytes from multiple sclerosis patients, researchers can use these cells to observe, in a culture dish, how multiple sclerosis develops and progresses. The improved protocol for deriving oligodendrocytes from iPSCs will also provide a platform for disease modeling, drug screening, and for replacing the damaged cells in the brain with healthy cells generated using this method.

“We are so close to finding new treatments and even cures for MS. The enhanced ability to derive the cells implicated in the disease will undoubtedly accelerate research for MS and many other diseases” said Susan L. Solomon, NYSCF Chief Executive Officer.

Valentina Fossati, NYSCF – Helmsley Investigator and senior author on the paper, said, “We believe that this protocol will help the MS field and the larger scientific community to better understand human oligodendrocyte biology and the process of myelination. This is the first step towards very exciting studies: the ability to generate human oligodendrocytes in large amounts will serve as an unprecedented tool for developing remyelinating strategies and the study of patient-specific cells may shed light on intrinsic pathogenic mechanisms that lead to progressive MS.”

NYSCF scientists established in this study that their improved the protocol for making myelin-forming cells worked and that the oligodendrocytes derived from the skin of these patients are functional, and able to form their own myelin when put into a mouse model. This is a definite step towards developing future autologous cell transplantation therapies in multiple sclerosis patients. These results also present new research venues to study multiple sclerosis and other diseases, since oligodendrocytes are implicated in many disorders. Therefore, Fossati and others have not only moved multiple sclerosis research forward, but also research on all demyelinating and central nervous system disorders.

“Oligodendrocytes are increasingly recognized as having an absolutely essential role in the function of the normal nervous system, as well as in the setting of neurodegenerative diseases, such as multiple sclerosis. The new work from the NYSCF Research Institute will help to improve our understanding of these important cells. In addition, being able to generate large numbers of patient-specific oligodendrocytes will support both cell transplantation therapeutics for demyelinating diseases and the identification of new classes of drugs to treat such disorders,” said Dr. Lee Rubin, NYSCF Scientific Advisor and Director of Translational Medicine at the Harvard Stem Cell Institute.

Multiple sclerosis is a chronic, inflammatory, demyelinating disease of the central nervous system, distinguished by recurrent episodes of demyelination and the consequent neurological symptoms. Primary progressive multiple sclerosis is the most severe form of multiple sclerosis, characterized by a steady neurological decline from the onset of the disease. Currently, there are no effective treatments or cures for primary progressive multiple sclerosis and treatments rely merely on symptom management.

Inhibiting Leukemic Stem Cells


Blood cancers, also known as leukemias, are, in many ways, a disease of stem cells. A core of cancerous stem cells divide and produce progeny that overpopulate, overwhelm, and in some cases invade and destroy other tissues. However many cancer treatments are designed to specifically attack the progeny of the cancer stem cells and not the leukemic stem cells. Therefore, the disease is destined to relapse, since the main driving entities of the leukemia are left to flourish while their progeny have been killed off.

Acute myeloid leukemia or AML is largely a disease of older adults, and even though the survival rates have increased, only about one out of every four adult patients survives for five years after the AML has been diagnosed. The mean survival time for this disease, which predominantly occurs in the elderly, is less than a year for patients over 65 years. Younger adults tend to do much better than older people. For example, more than half (50%) of the people under 45 diagnosed with AML will live for at least 5 years, and some will be cured. But in others, however, the AML will return and there is no way to tell in advance who has been cured and who will relapse. In people over 65 years of age the outlook tends not to be so good and around 12 out of 100 people (12%) are alive for more than 5 years.

Relapses and treatment failure in AML is almost certainly due to leukaemic stem cells, which cannot be completely eliminated during treatment. However, researcher Dr. Marin Ruthardt from the Hematology Department of the Medical Clinic II and Dr. Jessica Roos, Prof. Diester Steinhilber and Prof. Thorsten Jürgen Maier from the Institute for Pharmaceutical Chemistry has discovered a chink in the armor of leukemic stem cells. They report their data in the current edition of the journal “Cancer Research.”

AML stem cells require an enzyme called 5-lipoxygenase or 5-LO in order to survive. 5-LO plays a very important role in inflammatory diseases like asthma. Ruthardt, Roos, Steinhilber, and Maier and the members of their research teams showed that the leukemic stem cells in a subgroup of AML could be selectively and efficiently attacked by chemical inhibitors of 5-LO. These inhibitors killed the leukemic stem cells in cell culture model systems and in leukemia mouse models.

“These results provide the basis for the potential implementation of 5-LO-inhibitors as stem cell therapeutic agents for a sustained AML cure, although this must be investigated further in preclinical and clinical studies in humans,” explains Dr. Ruthardt.

Prof. Maier continued: “In addition, there are plans for further molecular biological studies with the objective of understanding exactly how the 5-LO inhibitors act on the leukemic cells.”

Hopefully these inhibitors can be fast-tracked for Phase I studies in human patients, and if they prove safe under clinical conditions, then maybe, if all seems well, they can be used to treat AML patients with aggressive cancers that do not respond well to more traditional cancer treatments.

Human Umbilical Cord Stem Cells Prevent Liver Failure in Mice


Acute liver failure results from massive liver damage over a short period of time. Viral infections (hepatitis B virus), drugs (acetaminophen, halothane), sepsis, Wilson’s disease, or autoimmune hepatitis can all cause acute liver failure, but acute liver failure can be life-threatening. Remember, the liver makes the vast majority of blood proteins such as clotting factors or albumin, and without a functioning liver, multi-organ failure ensues.

Liver transplantation can offer effective treatment of acute liver failure, except that there is a global shortage of available livers. The wife of my colleague at Spring Arbor University waited years and years for a liver until a liver was given to her as the result of a dying declaration. THe need is substantial and the supply is miniscule.

Several experiments have demonstrated that the transplantation of mesenchymal stem cells (MSCs) can treat acute liver failure. Human umbilical cord MSCs (hUCMSCs) can be differentiated into cells that closely resemble liver cells (known as hepatocytes) and these i-Heps, as they are called, display many liver-specific functions (secretion of albumin, storage of glycogen, see Campard et al., Gastroenterology 134 2008: 833-848). Likewise, UBMSCs secrete a host of interesting pro-regenerative molecules that seem to aid in liver recovery, regeneration, and healing when implanted into a damaged liver (see Banas et al., J Gastroenterol Hepatol 24 2009: 70-77; van Poll, et al., Hepatology 47 2008: 1634-1643; Moslem, et al., Cell Transplant 22(10) 2013: 1785-99).

To this end, scientists from the Chinese Academy of Sciences in Shenzhen, China have done an interesting side-by-side comparison of the ability of i-Heps and undifferentiated UCMSCs to mitigate acute liver damage in a mouse model.

Ruiping Zhou and Zhuokun Li in the laboratory of Zhi-Ying Chen and their colleagues injected a mixture of D-Galactosamine and a bacterial compound called LPS (lipopolysaccharide) into the bellies of NOD/SCID mice (non-obese diabetic, severe combined immunodeficiency) to induce acute liver damage. Half of the mice injected with this concoction died of acute liver failure, and autopsies of the mice in these experiments showed that half of the liver cells in their livers had been burned out. A control group was injected with salt solutions and showed no such liver damage.

Of these mice, some of the were injected with either two million UBMSCs or two million i-Heps, six hours after the induction of acute liver damage. The cells were given intravenously, in the tail vein.

Interestingly, both groups of mice – those that had received the UBMSCs and those that had received the i-Heps – showed improved survival and improved liver function as ascertained by several liver function tests. Liver biopsies revealed lower levels of cell death within the liver in both cases. Also when the liver is damaged, there are several blood tests that can reveal the presence of liver damage and indicate the degree of liver damage. In all cases where the D-Galactosamine and LPS were administered, the levels of these liver enzymes increased the first after their administration, but in those animals that received either UBMSCs or i-Heps, the markers of liver damage neither climbed as high, nor did they stay high as long, indicating the damage to the liver was mitigated by the infused stem cells.

Liver biopsies of the laboratory animals further confirmed the decreased levels of liver scarring in those animals that had received the stem cells with the D-galactosamine and LPS. Also the levels of cell division, indicative of healing, were increased in the stem cell-treated animals. Two weeks after the initial liver damage, large areas of the liver were observed that showed the signs of cell division, which indicates the presence of active liver repair activities at work in the stem cell-treated animals. Mice not treated with stem cells showed extensive liver damage with little signs of healing if they survived at all.

This interesting study shows that both hUCMSCs and hUCMSC-derived -i-Heps exhibited similar therapeutic effects for mouse acute liver failure. Also, when injected into the tail vein, the stem cells were able to home to the damaged liver and set up shop there. The liver regeneration in both cases seemed to be due to the stimulation of resident liver cells rather substantial contributions from the infused stem cells.

What does this mean for human regenerative medicine? Umbilical cord MSCs are probably a good source of material to treat liver failure. However, such cells will need to be matched to the tissue type of the patient. Secondly, a point emphasized in this paper is that MSCs should not be overly manipulated before they are used because some experiments with MSCs have shown that if these cells are grown in long-term culture, they can undergo malignant transformation (see Rosland, et al., Cancer Res 69 2009: 5331-5339).

Thus beefing the number of cells up for therapeutic purposes to treat a human, which is larger than a mouse, might represent a challenge. However, it is possible to expand MSCs in culture without transforming them into cancer cells, as long as it is done for a short period of time. Finally, MSCs represent an excellent alternative for the shortage of livers, since they can stimulate the liver’s internal healing systems to heal themselves on a short-term basis without the need for a liver transplantation. This sounds like a win-win situation. Of course more work must be done first. Preclinical studies like this must be expanded and then larger animals will need to be used as well before human clinical trials can be planned.

Stroke Patients Improve After Stem Cell Treatments


Neurologists at Imperial College, London have conducted a small pilot study in stroke patients who received stem cell treatments after their strokes. To date, their patients have shown tentative signs of neurological recovery six months after receiving the stem cell treatment.

According to the physicians attending these patients, all five patients who participated in the study have improved after the therapy. Even though these results are hopeful, larger and better controlled trials are required to confirm if the implanted stem cells are responsible for the improvements in these patients. Brain scans of the patients showed that damage caused by the stroke had reduced over time. However, similar improvements are seen in stroke patients as part of the normal recovery process.

When assessed after their six-month check ups, all of the participating patients fared better on standard measures of disability and impairment that are normally caused by stroke. Once again, it is difficult to determine if these improvements result from the stem cell treatments or from standard hospital care.

This pilot study was designed to assess only the safety of the experimental therapy (phase I clinical trial) and with so few patients and no control group to compare them with, it is impossible to draw conclusions about the effectiveness of the treatment at this time.

Paul Bentley is a consultant neurologist at Imperial College London, and his group is presently applying for funding to run a more powerful randomized, controlled trial on this stem cell therapy, which, Bentley hopes, could include at least 50 patients by next year.

“The improvements we saw in these patients are very encouraging, but it’s too early to draw definitive conclusions about the effectiveness of the therapy,” said Soma Banerjee, a lead author and consultant in stroke medicine at Imperial College Healthcare National Health System (NHS) Trust. “We need to do more tests to work out the best dose and timescale for treatment before starting larger trials.”

All five patients who participated in this study were treated within seven days of suffering a severe stroke. Each patient had a bone marrow sample extracted from their hip bones, and these bone marrow cells were processed in the laboratory to isolated the stem cells that give rise to blood cells and blood vessel lining cells (so-called CD34+ cells). These stem cells were infused into one of the main arteries that supplies blood to the brain.

CD34+ cells do not grow into fresh brain tissue, but they might release pro-healing chemicals that suppress inflammation and recruit and stimulate other cells to grow within the damaged brain tissue. Some of the implanted CD34+ cells might also form new blood vessels, said Bentley.

Four out of five of the patients had the most serious type of stroke, and typically, only 4% of these patients survive and are able to live independently after six months. In the pilot study, published in Stem Cells Translational Medicine, all four were alive and three were independent six months later.

“Although they mention some improvement of some of the patients, this could be just chance, or wishful thinking, or due to the special care these patients may have received simply because they were in a trial,” said Robin Lovell-Badge, head of developmental genetics at the MRC’s National Institute for Medical Research in London.

Caution is certainly required in the interpretation of this pilot study, but I think that these results definitely merit a Phase II trial to determine if the improvements are stem cell-independent or stem cell-dependent.

Human Stem Cell-Derived Neurons Grow New Axons In Spinal Cord Injured Rats


A stem cell-based treatment for spinal cord injury took one more baby step forward when scientists from the laboratory of Mark Tuszynski at the at the University of California, San Diego used cells derived from an elderly man’s skin to regrow neural connections in rats with damaged spinal cords.

Tuszynski and others published their results in the Aug. 7 online issue of the journal Neuron. In that paper, Tuszynski and his co-worker report that human stem cells triggered the growth of numerous axons in the damaged spinal cord. Axons are those fibers that extend from the main part or body a neuron (nerve cell) that serve to send electrical impulses away from the body to other cells. Some of these new axons even grew into the animals’ brains.

Axon picture

Dr. Mark Tuszynski is a professor of neurosciences at the University of California, San Diego. “This degree of growth in axons has not been appreciated before,” he said. However, Tuszynski also cautioned that there is still much to be learned about how these newly established nerve fibers behave in laboratory animals. He likened the potential for stem-cell-induced axon growth to nuclear fusion. If it’s contained, you get energy; if it’s not contained, you get an explosion. “Too much axon growth into the wrong places would be a bad thing,” Tuszynski added.

Stem cell researchers have examined the potential for stem cells to restore functioning nerve connections in people with spinal cord injuries. Embryonic stem cells have been used to make new neurons and to also make “oligodendrocyte progenitor cells” or OPCs, which make the insulating myelin sheath that enwraps the axons of spinal nerves. However, several other types of stem cells can make OPCs and new neurons and these stem cells do not come from embryos (for more, see chapter 27 of my book, The Stem Cell Epistles).

In this study, Tuszynski and his team used induced pluripotent stem cells or iPSCs, which are derived from mature adult cells by means of genetic engineering and cell culture techniques. They used cells from a healthy 86-year-old man and genetically reprogrammed so that they were reprogrammed into iPSCs. These iPSCs were then differentiated into neurons that were implanted into a special scaffold embedded with proteins called growth factors, and then grafted into the spinal cords of laboratory rats with spinal cord injuries.

Over the course of several months, these animals showed new, mature neurons and extensive growth in the cells’ axons. These fibers grew through the injury-related scar tissue in the animals’ spinal cords and connected with resident rat neurons.

This is an enormous advance, because the wounded spinal cord creates a “Glial scar” that contains a host of molecules that repel growing axons. Even though this glial scar prevents the immune system from leaking into the spinal cord and destroying it, this same scar prevents the regeneration of damaged neurons and their severed axons.

Glial scar axon repulsion

Dr. David Langer, director of neurosurgery at Lenox Hill Hospital in New York City said: “One of the big obstacles [in this type of research] is this area of scarring in the spinal cord. Getting neurons to traverse it is a real challenge,” said Langer, who was not involved in the research. “The beauty of this study,” he said, “is that they got the neurons to survive and traverse the scar.”

Langer also cautioned, much like Tuszynski, that this experimental success is just a preliminary step. There are, in his words, “huge questions” as to whether or not these axons can make appropriate connections and actually restore function to spine-damaged lab animals. “It’s not just a matter of having the cables,” Langer said. “The wiring has to work.”

And even if this stem cell approach does pan out in animals, Langer added, it would all have to be translated to humans. “We have a long way to go until we’re there,” he said. “It’s not that people shouldn’t have hope. But it should be a realistic hope.”

A few biotech companies have already launched early-stage clinical trials using embryonic (Geron) or fetal stem cells (StemCells Inc) to treat patients with spinal cord injuries. But Tuszynski said his team’s findings offer a cautionary note about moving to human trials too quickly. “We still have a lot to learn,” he said. “We want to be very sure these axons don’t make inappropriate connections. And we need to see if the new connections formed by these axons are stable.”

Ideally, Tuszynski added, if stem cells were to be used in treating spinal cord injuries, they’d be generated as they were in this study — by creating them from a patient’s own cells. That way, he explained, patients would not need immune-suppressing drugs afterward.

Fat-Based Stem Cells Support New Brain Cell Growth in Alzheimer’s Disease Mice


Alzheimer’s disease (AD) causes progressive death of brain cells and dementia. The loss of memory, coordination, and eventually motor function is relentless and horrific, and causes extensive suffering, financial pressures and loss. Stem cell treatments have been proposed as a treatment for AD, but such treatments have met resistance because of the complex pathology of AD. Introducing new neurons into the brain will do little good if cells are normally dying. However, some work with laboratory animals has suggested that stem cell treatments can benefit animals with conditions that approximately AD (see Kim S, et al., PLoS One. 2012;7(9):e45757; Bae JS, et al., Curr Alzheimer Res. 2013 Jun;10(5):524-31). However there are few studies that examine the therapeutic effect of mesenchymal stem cells from fat tissue or “adipose-derived stem cells” on mice with AD, and the effect of these cells on the oxidative injury that tends to accompany AD, and if these stem cells stimulate the generation of new neurons in the brains of AD mice.

Now we have evidence that transplantation of mesenchymal stem cells can stimulate for formation of new brain cells in adult rat or mouse models of AD and improve tissue structure and function after a stroke. Dr. Yufang Yan and her team from the School of Life Sciences at Tsinghua University, China transplanted adipose-derived stromal cells (ADSCs) into a part of the brain known as the hippocampus of mice that express the APP/PS1 transgene. Such mice show an AD-like disease, with memory loss and amyloid plaques that form in the brain.

Transplantation of ADSCs in these AD model mice decreased oxidative stress and promoted the growth of new neurons and glial cells in the subgranular and subventricular zones of the hippocampus, and, consequently improved the cognitive impairment in APP/PS1 transgenic AD mice.

These findings were published in Neural Regeneration Research (Vol. 9, No. 8, 2014), and provide theoretical and experimental evidence that ADSCs can be used to treat AD patients.