These are definitely strange, unusual and challenging times. Every day seems to bring new restrictions on what we can and should do. All, of course, in the name of protecting us and helping us avoid a potentially deadly virus. We all hope this will soon pass but we also know the bigger impact of the coronavirus is likely to linger for many months, perhaps even years.
With that in mind a few people have asked us why we are still going ahead with our Facebook Live ‘Ask the Stem Cell Team About Autism’ event this Thursday, March 19th at 12pm PDT. It’s a good question. And the answer is simple. Because there is still a need for good, thoughtful information about the potential for stem cells to help families who have a loved one with autism. And because we still need to do all we can to dispel the bad information out there and warn people about the bogus clinics offering unproven therapies.
In many ways Facebook Live is the perfect way to deliver this information. It allows us to reach out to large numbers of people without having them in the same room. We can educate not contaminate.
And we have some great experts to discuss the use of stem cells in helping people with autism.
The event features Dr. Alysson Muotri from UC San Diego. We have written about his work with stem cells for autism in the past. And CIRM’s own Associate Director for Discovery and Translation, Dr. Kelly Shepard.
But we also want you to be a part of this as well. So, join us online for the event. You can post comments and questions during the event, and we’ll do our best to answer them. Or you can send us in questions ahead of time to firstname.lastname@example.org.
If you were unable to tune in while we were live, not to worry, you you can watch it here on our Facebook page
On December 12th we hosted our latest ‘Facebook Live: Ask the Stem Cell Team’ event. This time around we really did mean team. We had a host of our Science Officers answering questions from friends and supporters of CIRM. We got a lot of questions and didn’t have enough time to address them all. So here’s answers to all the questions.
What are the obstacles to using partial cellular reprogramming to return people’s entire bodies to a youthful state.Paul Hartman. San Leandro, California
Dr. Kelly Shepard: Certainly, scientists have observed that various manipulations of cells, including reprogramming, partial reprogramming, de-differentiation and trans-differentiation, can restore or change properties of cells, and in some cases, these changes can reflect a more “youthful” state, such as having longer telomeres, better proliferative capacity, etc. However, some of these same rejuvenating properties, outside of their normal context, could be harmful or deadly, for example if a cell began to grow and divide when or where it shouldn’t, similar to cancer. For this reason, I believe the biggest obstacles to making this approach a reality are twofold: 1) our current, limited understanding of the nature of partially reprogrammed cells; and 2) our inability to control the fate of those cells that have been partially reprogrammed, especially if they are inside a living organism. Despite the challenges, I think there will be step wise advances where these types of approaches will be applied, starting with specific tissues. For example, CIRM has recently funded an approach that uses reprogramming to make “rejuvenated” versions of T cells for fighting lung cancer. There is also a lot of interest in using such approaches to restore the reparative capacity of aged muscle. Perhaps some successes in these more limited areas will be the basis for expanding to a broader use.
What’s going on with Stanford’s stem cell trials for stroke? I remember the first trial went really well In 2016 have not heard anything about since? Elvis Arnold
Dr. Lila Collins: Hi Elvis, this is an evolving story. I believe you are referring to SanBio’s phase 1/2a stroke trial, for which Stanford was a site. This trial looked at the safety and feasibility of SanBio’s donor or allogeneic stem cell product in chronic stroke patients who still had motor deficits from their strokes, even after completing physical therapy when natural recovery has stabilized. As you note, some of the treated subjects had promising motor recoveries.
SanBio has since completed a larger, randomized phase 2b trial in stroke, and they have released the high-level results in a press release. While the trial did not meet its primary endpoint of improving motor deficits in chronic stroke, SanBio conducted a very similar randomized trial in patients with stable motor deficits from chronic traumatic brain injury (TBI). In this trial, SanBio saw positive results on motor recovery with their product. In fact, this product is planned to move towards a conditional approval in Japan and has achieved expedited regulatory status in the US, termed RMAT, in TBI which means it could be available more quickly to patients if all goes well. SanBio plans to continue to investigate their product in stroke, so I would stay tuned as the work unfolds.
Also, since you mentioned Stanford, I should note that Dr Gary Steinberg, who was a clinical investigator in the SanBio trial you mentioned, will soon be conducting a trial with a different product that he is developing, neural progenitor cells, in chronic stroke. The therapy looks promising in preclinical models and we are hopeful it will perform well for patients in the clinic.
I am a stroke survivor will stem cell treatment able to restore my motor skills?Ruperto
Dr. Lila Collins:
Hi Ruperto. Restoring motor loss after stroke is a very active area of research. I’ll touch upon a few ongoing stem cell trials. I’d just like to please advise that you watch my colleague’s comments on stem cell clinics (these can be found towards the end of the blog) to be sure that any clinical research in which you participate is as safe as possible and regulated by FDA.
Back to stroke, I mentioned SanBio’s ongoing work to address motor skill loss in chronic stroke earlier. UK based Reneuron is also conducting a phase 2 trial, using a neural progenitor cell as a candidate therapy to help recover persistent motor disability after stroke (chronic). Dr Gary Steinberg at Stanford is also planning to conduct a clinical trial of a human embryonic stem cell-derived neuronal progenitor cell in stroke.
There is also promising work being sponsored by Athersys in acute stroke. Athersys published results from their randomized, double blinded placebo controlled Ph2 trial of their Multistem product in patients who had suffered a stroke within 24-48 hours. After intravenous delivery, the cells improved a composite measure of stroke recovery, including motor recovery. Rather than acting directly on the brain, Multistem seems to work by traveling to the spleen and reducing the inflammatory response to a stroke that can make the injury worse.
Athersys is currently recruiting a phase 3 trial of its Multistem product in acute stroke (within 1.5 days of the stroke). The trial has an accelerated FDA designation, called RMAT and a special protocol assessment. This means that if the trial is conducted as planned and it reaches the results agreed to with the FDA, the therapy could be cleared for marketing. Results from this trial should be available in about two years.
Questions from several hemorrhagic stroke survivors who say most clinical trials are for people with ischemic strokes. Could stem cells help hemorrhagic stroke patients as well?
Dr. Lila Collins:
Regarding hemorrhagic stroke, you are correct the bulk of cell therapies for stroke target ischemic stroke, perhaps because this accounts for the vast bulk of strokes, about 85%.
That said, hemorrhagic strokes are not rare and tend to be more deadly. These strokes are caused by bleeding into or around the brain which damages neurons. They can even increase pressure in the skull causing further damage. Because of this the immediate steps treating these strokes are aimed at addressing the initial bleeding insult and the blood in the brain.
While most therapies in development target ischemic stroke, successful therapies developed to repair neuronal damage or even some day replace lost neurons, could be beneficial after hemorrhagic stroke as well.
I had an Ischemic stroke in 2014, and my vision was also affected. Can stem cells possibly help with my vision issues. James Russell
Dr. Lila Collins:
Hi James. Vision loss from stroke is complex and the type of loss depends upon where the stroke occurred (in the actual eye, the optic nerve or to the other parts of the brain controlling they eye or interpreting vision). The results could be:
Visual loss from damage to the retina
You could have a normal eye with damage to the area of the brain that controls the eye’s movement
You could have damage to the part of the brain that interprets vision.
You can see that to address these various issues, we’d need different cell replacement approaches to repair the retina or the parts of the brain that were damaged.
Replacing lost neurons is an active effort that at the moment is still in the research stages. As you can imagine, this is complex because the neurons have to make just the right connections to be useful.
Is there any stem cell therapy for optical nerve damage? Deanna Rice
Dr. Ingrid Caras: There is currently no proven stem cell therapy to treat optical nerve damage, even though there are shady stem cell clinics offering treatments. However, there are some encouraging early gene therapy studies in mice using a virus called AAV to deliver growth factors that trigger regeneration of the damaged nerve. These studies suggest that it may be possible to restore at least some visual function in people blinded by optic nerve damage from glaucoma
I read an article about ReNeuron’s retinitis pigmentosa clinical trial update. In the article, it states: “The company’s treatment is a subretinal injection of human retinal progenitors — cells which have almost fully developed into photoreceptors, the light-sensing retinal cells that make vision possible.” My question is: If they can inject hRPC, why not fully developed photoreceptors?Leonard
Dr. Kelly Shepard: There is evidence from other studies, including from other tissue types such as blood, pancreas, heart and liver, that fully developed (mature) cell types tend not to engraft as well upon transplantation, that is the cells do not establish themselves and survive long term in their new environment. In contrast, it has been observed that cells in a slightly less “mature” state, such as those in the progenitor stage, are much more likely to establish themselves in a tissue, and then differentiate into more mature cell types over time. This question gets at the crux of a key issue for many new therapies, i.e. what is the best cell type to use, and the best timing to use it.
My question for the “Ask the Stem Cell Team” event is: When will jCyte publish their Phase IIb clinical trial results. Chris Allen
Dr. Ingrid Caras: The results will be available sometime in 2020.
I understand the hRPC cells are primarily neurotropic (rescue/halt cell death); however, the literature also says hRPC can become new photoreceptors. My questions are:Approximately what percentage develop into functioning photoreceptors? And what percentage of the injected hRPC are currently surviving?Leonard Furber, an RP Patient
Dr. Kelly Shepard: While we can address these questions in the lab and in animal models, until there is a clinical trial, it is not possible to truly recreate the environment and stresses that the cells will undergo once they are transplanted into a human, into the site where they are expected to survive and function. Thus, the true answer to this question may not be known until after clinical trials are performed and the results can be evaluated. Even then, it is not always possible to monitor the fate of cells after transplantation without removing tissues to analyze (which may not be feasible), or without being able to transplant labeled cells that can be readily traced.
Dr. Ingrid Caras – Although the cells have been shown to be capable of developing into photoreceptors, we don’t know if this actually happens when the cells are injected into a patient’s eye. The data so far suggest that the cells work predominantly by secreting growth factors that rescue damaged retinal cells or even reverse the damage. So one possible outcome is that the cells slow or prevent further deterioration of vision. But an additional possibility is that damaged retinal cells that are still alive but are not functioning properly may become healthy and functional again which could result in an improvement in vision.
What advances have been made using stem cells for the treatment of Type 2 Diabetes?Mary Rizzo
Dr. Ross Okamura: Type 2 Diabetes (T2D) is a disease where the body is unable to maintain normal glucose levels due to either resistance to insulin-regulated control of blood sugar or insufficient insulin production from pancreatic beta cells. The onset of disease has been associated with lifestyle influenced factors including body mass, stress, sleep apnea and physical activity, but it also appears to have a genetic component based upon its higher prevalence in certain populations.
Type 1 Diabetes (T1D) differs from T2D in that in T1D patients the pancreatic beta cells have been destroyed by the body’s immune system and the requirement for insulin therapy is absolute upon disease onset rather than gradually developing over time as in many T2D cases. Currently the only curative approach to alleviate the heavy burden of disease management in T1D has been donor pancreas or islet transplantation. However, the supply of donor tissue is small relative to the number of diabetic patients. Donor islet and pancreas transplants also require immune suppressive drugs to prevent allogenic immune rejection and the use of these drugs carry additional health concerns. However, for some patients with T1D, especially those who may develop potentially fatal hypoglycemia, immune suppression is worth the risk.
To address the issue of supply, there has been significant activity in stem cell research to produce insulin secreting beta cells from pluripotent stem cells and recent clinical data from Viacyte’s CIRM funded trial indicates that implanted allogeneic human stem cell derived cells in T1D patients can produce circulating c-peptide, a biomarker for insulin. While the trial is not designed specifically to cure insulin-dependent T2D patients, the ability to produce and successfully engraft stem cell-derived beta cells would be able to help all insulin-dependent diabetic patients.
It’s also worth noting that there is a sound scientific reason to clinically test a patient-derived pluripotent stem cell-based insulin-producing cells in insulin-dependent T2D diabetic patients; the cells in this case could be evaluated for their ability to cure diabetes in the absence of needing to prevent both allogeneic and autoimmune responses.
SPINAL CORD INJURY
Is there any news on clinical trials for spinal cord injury? Le Ly
Kevin McCormack: The clinical trial CIRM was funding, with Asterias (now part of a bigger company called Lineage Cell Therapeutics, is now completed and the results were quite encouraging. In a news release from November of 2019 Brian Culley, CEO of Lineage Cell Therapeutics, described the results this way.
“We remain extremely excited about the potential for OPC1 (the name of the therapy used) to provide enhanced motor recovery to patients with spinal cord injuries. We are not aware of any other investigative therapy for SCI (spinal cord injury) which has reported as encouraging clinical outcomes as OPC1, particularly with continued improvement beyond 1 year. Overall gains in motor function for the population assessed to date have continued, with Year 2 assessments measuring the same or higher than at Year 1. For example, 5 out of 6 Cohort 2 patients have recovered two or more motor levels on at least one side as of their Year 2 visit whereas 4 of 6 patients in this group had recovered two motor levels as of their Year 1 visit. To put these improvements into perspective, a one motor level gain means the ability to move one’s arm, which contributes to the ability to feed and clothe oneself or lift and transfer oneself from a wheelchair. These are tremendously meaningful improvements to quality of life and independence. Just as importantly, the overall safety of OPC1 has remained excellent and has been maintained 2 years following administration, as measured by MRI’s in patients who have had their Year 2 follow-up visits to date. We look forward to providing further updates on clinical data from SCiStar as patients continue to come in for their scheduled follow up visits.”
Lineage Cell Therapeutics plans to meet with the FDA in 2020 to discuss possible next steps for this therapy.
In the meantime the only other clinical trial I know that is still recruiting is one run by a company called Neuralstem. Here is a link to information about that trial on the www.clinicaltrials.gov website.
Now that the Brainstorm ALS trial is finished looking for new patients do you have any idea how it’s going and when can we expect to see results? Angela Harrison Johnson
Dr. Ingrid Caras: The treated patients have to be followed for a period of time to assess how the therapy is working and then the data will need to be analyzed. So we will not expect to see the results probably for another year or two.
Are there treatments for autism or fragile x using stem cells? Magda Sedarous
Dr. Kelly Shepard: Autism and disorders on the autism spectrum represent a collection of many different disorders that share some common features, yet have different causes and manifestations, much of which we still do not understand. Knowing the origin of a disorder and how it affects cells and systems is the first step to developing new therapies. CIRM held a workshop on Autism in 2009 to brainstorm potential ways that stem cell research could have an impact. A major recommendation was to exploit stem cells and new technological advances to create cells and tissues, such as neurons, in the lab from autistic individuals that could then be studied in great detail. CIRM followed this recommendation and funded several early-stage awards to investigate the basis of autism, including Rett Syndrome, Fragile X, Timothy Syndrome, and other spectrum disorders. While these newer investigations have not yet led to therapies that can be tested in humans, this remains an active area of investigation. Outside of CIRM funding, we are aware of more mature studies exploring the effects of umbilical cord blood or other specific stem cell types in treating autism, such as an ongoing clinical trial conducted at Duke University.
What is happening with Parkinson’s research? Hanifa Gaphoor
Dr. Kent Fitzgerald: Parkinson’s disease certainly has a significant amount of ongoing work in the regenerative medicine and stem cell research.
The nature of cell loss in the brain, specifically the dopaminergic cells responsible for regulating the movement, has long been considered a good candidate for cell replacement therapy.
This is largely due to the hypothesis that restoring function to these cells would reverse Parkinson’s symptoms. This makes a lot of sense as front line therapy for the disease for many years has been dopamine replacement through L-dopa pills etc. Unfortunately, over time replacing dopamine through a pill loses its benefit, whereas replacing or fixing the cells themselves should be a more permanent fix.
Because a specific population of cells in one part of the brain are lost in the disease, multiple labs and clinicians have sought to replace or augment these cells by transplantation of “new” functional cells able to restore function to the area an theoretically restore voluntary motor control to patients with Parkinson’s disease.
Early clinical research showed some promise, however also yielded mixed results, using fetal tissue transplanted into the brains of Parkinson’s patients. As it turns out, the cell types required to restore movement and avoid side effects are somewhat nuanced. The field has moved away from fetal tissue and is currently pursuing the use of multiple stem cell types that are driven to what is believed to be the correct subtype of cell to repopulate the lost cells in the patient.
One project CIRM sponsored in this area with Jeanne Loring sought to develop a cell replacement therapy using stem cells from the patients themselves that have been reprogrammed into the kinds of cell damaged by Parkinson’s. This type of approach may ultimately avoid issues with the cells avoiding rejection by the immune system as can be seen with other types of transplants (i.e. liver, kidney, heart etc).
Still, others are using cutting edge gene therapy technology, like the clinical phase project CIRM is sponsoring with Krystof Bankiewicz to investigate the delivery of a gene (GDNF) to the brain that may help to restore the activity of neurons in the Parkinson’s brain that are no longer working as they should.
The bulk of the work in the field of PD at the present remains centered on replacing or restoring the dopamine producing population of cells in the brain that are affected in disease.
Any plans for Huntington’s?Nikhat Kuchiki
Dr. Lisa Kadyk: The good news is that there are now several new therapeutic approaches to Huntington’s Disease that are at various stages of preclinical and clinical development, including some that are CIRM funded. One CIRM-funded program led by Dr. Leslie Thompson at UC Irvine is developing a cell-based therapeutic that consists of neural stem cells that have been manufactured from embryonic stem cells. When these cells are injected into the brain of a mouse that has a Huntington’s Disease mutation, the cells engraft and begin to differentiate into new neurons. Improvements are seen in the behavioral and electrophysiological deficits in these mutant mice, suggesting that similar improvements might be seen in people with the disease. Currently, CIRM is funding Dr. Thompson and her team to carry out rigorous safety studies in animals using these cells, in preparation for submitting an application to the FDA to test the therapy in human patients in a clinical trial.
There are other, non-cell-based therapies also being tested in clinical trials now, using anti-sense oligonucleotides (Ionis, Takeda) to lower the expression of the Huntington protein. Another HTT-lowering approach is similar – but uses miRNAs to lower HTT levels (UniQure,Voyager)
TRAUMATIC BRAIN INJURY (TBI)
My 2.5 year old son recently suffered a hypoxic brain injury resulting in motor and speech disabilities. There are several clinical trials underway for TBI in adults. My questions are:
Will the results be scalable to pediatric use and how long do you think it would take before it is available to children?
I’m wondering why the current trials have chosen to go the route of intracranial injections as opposed to something slightly less invasive like an intrathecal injection?
Is there a time window period in which stem cells should be administered by, after which the administration is deemed not effective?
Dr. Kelly Shepard: TBI and other injuries of the nervous system are characterized by a lot of inflammation at the time of injury, which is thought to interfere with the healing process- and thus some approaches are intended to be delivered after that inflammation subsides. However, we are aware of approaches that intend to deliver a therapy to a chronic injury, or one that has occurred previously. Thus, the answer to this question may depend on how the intended therapy is supposed to work. For example, is the idea to grow new neurons, or is it to promote the survival of neurons of other cells that were spared by the injury? Is the therapy intended to address a specific symptom, such as seizures? Is the therapy intended to “fill a gap” left behind after inflammation subsides, which might not restore all function but might ameliorate certain symptoms.? There is still a lot we don’t understand about the brain and the highly sophisticated network of connections that cannot be reversed by only replacing neurons, or only reducing inflammation, etc. However, if trials are well designed, they should yield useful information even if the therapy is not as effective as hoped, and this information will pave the way to newer approaches and our technology and understanding evolves.
We have had a doctor recommending administering just the growth factors derived from MSC stem cells. Does the science work that way? Is it possible to isolate the growth factors and boost the endogenous growth factors by injecting allogenic growth factors?
Dr. Stephen Lin: Several groups have published studies on the therapeutic effects in non-human animal models of using nutrient media from MSC cultures that contain secreted factors, or extracellular vesicles from cells called exosomes that carry protein or nucleic acid factors. Scientifically it is possible to isolate the factors that are responsible for the therapeutic effect, although to date no specific factor or combination of factors have been identified to mimic the effects of the undefined mixtures in the media and exosomes. At present no regulatory approved clinical therapy has been developed using this approach.
PREDATORY STEM CELL CLINICS
What practical measures are being taken to address unethical practitioners whose bad surgeries are giving stem cell advances a bad reputation and are making forward research difficult?Kathy Jean Schultz
Dr. Geoff Lomax: Terrific question! I have been doing quite a bit research into the history of this issue of unethical practitioners and I found an 1842 reference to “quack medicines.” Clearly this is nothing new. In that day, the author appealed to make society “acquainted with the facts.”
In California, we have taken steps to (1) acquaint patients with the facts about stem cell treatments and (2) advance FDA authorized treatments for unmet medical needs.
First, CIRM work with Senator Hernandez in 2017 to write a law the requires provides to disclose to patient that a stem cell therapy has not been approved by the Food and Drug administration.
We continue to work with the State Legislature and Medical Board of California to build on policies that require accurate disclosure of the facts to patients.
Second, our clinical trial network the — Alpha Stem Cell Clinics – have supported over 100 FDA-authorized clinical trials to advance responsible clinical research for unmet medical needs.
I’m curious if adipose stem cell being used at clinics at various places in the country is helpful or beneficial?Cheri Hicks
Adipose tissue has been widely used particularly in plastic and reconstructive surgery. Many practitioners suggest adipose cells are beneficial in this context. With regard to regenerative medicine and / or the ability to treat disease and injury, I am not aware of any large randomized clinical trials that demonstrate the safety and efficacy of adipose-derived stem cells used in accordance with FDA guidelines.
I went to a “Luncheon about Stem Cell Injections”. It sounded promising. I went thru with it and got the injections because I was desperate from my knee pain. The price of stem cell injections was $3500 per knee injection. All went well. I have had no complications, but haven’t noticed any real major improvement, and here I am a year later. My questions are:
1) I wonder on where the typical injection cells are coming from?
2) I wonder what is the actual cost of the cells?
3) What kind of results are people getting from all these “pop up” clinics or established clinics that are adding this to there list of offerings?
Dr. Geoff Lomax: You raise a number of questions and point here; they are all very good and it’s is hard to give a comprehensive response to each one, but here is my reaction:
There are many practitioners in the field of orthopedics who sincerely believe in the potential of cell-based treatments to treat injury / pain
Most of the evidence presented is case reports that individuals have benefited
The challenge we face is not know the exact type of injury and cell treatments used.
Well controlled clinical trials would really help us understand for what cells (or cell products) and for what injury would be helpful
Prices of $3000 to $5000 are not uncommon, and like other forms of private medicine there is often a considerable mark-up in relation to cost of goods.
You are correct that there have not been reports of serious injury for knee injections
However the effectiveness is not clear while simultaneously millions of people have been aided by knee replacements.
Do stem cells have benefits for patients going through chemotherapy and radiation therapy?Ruperto
Dr. Kelly Shepard: The idea that a stem cell therapy could help address effects of chemotherapy or radiation is being and has been pursued by several investigators over the years, including some with CIRM support. Towards the earlier stages, people are looking at the ability of different stem cell-derived neural cell preparations to replace or restore function of certain brain cells that are damaged by the effects of chemotherapy or radiation. In a completely different type of approach, a group at City of Hope is exploring whether a bone marrow transplant with specially modified stem cells can provide a protective effect against the chemotherapy that is used to treat a form of brain cancer, glioblastoma. This study is in the final stage of development that, if all goes well, culminates with application to the FDA to allow initiation of a clinical trial to test in people.
Dr. Ingrid Caras: That’s an interesting and valid question. There is a Phase 1 trial ongoing that is evaluating a novel type of stem/progenitor cell from the umbilical cord of healthy deliveries. In animal studies, these cells have been shown to reduce the toxic effects of chemotherapy and radiation and to speed up recovery. These cells are now being tested in a First-in-human clinical trial in patients who are undergoing high-dose chemotherapy to treat their disease.
There is a researcher at Stanford, Michelle Monje, who is investigating that the role of damage to stem cells in the cognitive problems that sometimes arise after chemo- and radiation therapy (“chemobrain”). It appears that damage to stem cells in the brain, especially those responsible for producing oligodendrocytes, contributes to chemobrain. In CIRM-funded work, Dr. Monje has identified small molecules that may help prevent or ameliorate the symptoms of chemobrain.
Is it possible to use a technique developed to fight one disease to also fight another? For instance, the bubble baby disease, which has cured (I think) more than 50 children, may also help fight sickle cell anemia? Don Reed.
Dr. Lisa Kadyk: Hi Don. Yes, the same general technique can often be applied to more than one disease, although it needs to be “customized” for each disease. In the example you cite, the technique is an “autologous gene-modified bone marrow transplant” – meaning the cells come from the patient themselves. This technique is relevant for single gene mutations that cause diseases of the blood (hematopoietic) system. For example, in the case of “bubble baby” diseases, a single mutation can cause failure of immune cell development, leaving the child unable to fight infections, hence the need to have them live in a sterile “bubble”. To cure that disease, blood stem cells, which normally reside in the bone marrow, are collected from the patient and then a normal version of the defective gene is introduced into the cells, where it is incorporated into the chromosomes. Then, the corrected stem cells are transplanted back into the patient’s body, where they can repopulate the blood system with cells expressing the normal copy of the gene, thus curing the disease.
A similar approach could be used to treat sickle cell disease, since it is also caused by a single gene mutation in a gene (beta hemoglobin) that is expressed in blood cells. The same technique would be used as I described for bubble baby disease but would differ in the gene that is introduced into the patient’s blood stem cells.
Is there any concern that CIRM’s lack of support in basic research will hamper the amount of new approaches that can reach clinical stages? Jason
Dr. Kelly Shepard: CIRM always has and continues to believe that basic research is vital to the field of regenerative medicine. Over the past 10 years CIRM has invested $904 million in “discovery stage/basic research”, and about $215 million in training grants that supported graduate students, post docs, clinical fellows, undergraduate, masters and high school students performing basic stem cell research. In the past couple of years, with only a limited amount of funds remaining, CIRM made a decision to invest most of the remaining funds into later stage projects, to support them through the difficult transition from bench to bedside. However, even now, CIRM continues to sponsor some basic research through its Bridges and SPARK Training Grant programs, where undergraduate, masters and even high school students are conducting stem cell research in world class stem cell laboratories, many of which are the same laboratories that were supported through CIRM basic research grants over the past 10 years. While basic stem cell research continues to receive a substantial level of support from the NIH ($1.8 billion in 2018, comprehensively on stem cell projects) and other funders, CIRM believes continued support for basic research, especially in key areas of stem cell research and vital opportunities, will always be important for discovering and developing new treatments.
What is the future of the use of crispr cas9 in clinical trials in california/globally. Art Venegas
Dr. Kelly Shepard: CRISPR/Cas9 is a powerful gene editing tool. In only a few years, CRISPR/Cas9 technology has taken the field by storm and there are already a few CRISPR/Cas9 based treatments being tested in clinical trials in the US. There are also several new treatments that are at the IND enabling stage of development, which is the final testing stage required by the FDA before a clinical trial can begin. Most of these clinical trials involving CRISPR go through an “ex vivo” approach, taking cells from the patient with a disease causing gene, correcting the gene in the laboratory using CRISPR, and reintroducing the cells carrying the corrected gene back into the patient for treatment. Sickle cell disease is a prime example of a therapy being developed using this strategy and CIRM funds two projects that are preparing for clinical trials with this approach. CRISPR is also being used to develop the next generation of cancer T-cell therapies (e.g. CAR-T), where T-cells – a vital part of our immune system – are modified to target and destroy cancer cell populations. Using CRISPR to edit cells directly in patients “in vivo” (inside the body) is far less common currently but is also being developed. It is important to note that any FDA sanctioned “in vivo” CRISPR clinical trial in people will only modify organ-specific cells where the benefits cannot be passed on to subsequent generations. There is a ban on funding for what are called germ line cells, where any changes could be passed down to future generations.
CIRM is currently supporting multiple CRISPR/Cas9 gene editing projects in California from the discovery or most basic stage of research, through the later stages before applying to test the technique in people in a clinical trial.
While the field is new – if early safety signals from the pioneering trials are good, we might expect a number of new CRISPR-based approaches to enter clinical testing over the next few years. The first of these will will likely be in the areas of bone marrow transplant to correct certain blood/immune or metabolic diseases, and cancer immunotherapies, as these types of approaches are the best studied and furthest along in the pipeline.
Explain the differences between gene therapy and stem cell therapy?Renee Konkol
Dr. Stephen Lin: Gene therapy is the direct modification of cells in a patient to treat a disease. Most gene therapies use modified, harmless viruses to deliver the gene into the patient. Gene therapy has recently seen many success in the clinic, with the first FDA approved therapy for a gene induced form of blindness in 2017 and other approvals for genetic forms of smooth muscle atrophy and amyloidosis.
Stem cell therapy is the introduction of stem cells into patients to treat a disease, usually with the purpose of replacing damaged or defective cells that contribute to the disease. Stem cell therapies can be derived from pluripotent cells that have the potential to turn into any cell in the body and are directed towards a specific organ lineage for the therapy. Stem cell therapies can also be derived from other cells, called progenitors, that have the ability to turn into a limited number of other cells in the body. for example hematopoietic or blood stem cells (HSCs), which are found in bone marrow, can turn into other cells of the blood system including B-cells and T-cells: while mesenchymal stem cells (MSCs), which are usually found in fat tissue, can turn into bone, cartilage, and fat cells. The source of these cells can be from the patient’s own body (autologous) or from another person (allogeneic).
Gene therapy is often used in combination with cell therapies when cells are taken from the patient and, in the lab, modified genetically to correct the mutation or to insert a correct form of the defective gene, before being returned to patients. Often referred to as “ex vivo gene therapy” – because the changes are made outside the patient’s body – these therapies include Chimeric Antigen Receptor T (CAR-T) cells for cancer therapy and gene modified HSCs to treat blood disorders such as severe combined immunodeficiency and sickle cell disease. This is an exciting area that has significantly improved and even cured many people already.
Currently, how can the outcome of CIRM stem cell medicine projects and clinical trials be soundly interpreted when their stem cell-specific doses are not known?James L. Sherley, M.D., Ph.D., Director. Asymmetrex, LLC
Dr. Stephen Lin: Stem cell therapies that receive approval to conduct clinical trials must submit a package of data to the FDA that includes studies that demonstrate their effectiveness, usually in animal models of the disease that the cell therapy is targeting. Those studies have data on the dose of the cell therapy that creates the therapeutic effect, which is used to estimate cell doses for the clinical trial. CIRM funds discovery and translational stage awards to conduct these types of studies to prepare cell therapies for clinical trials. The clinical trial is also often designed to test multiple doses of the cell therapy to determine the one that has the best therapeutic effect. Dosing can be very challenging with cell therapies because of issues including survival, engraftment, and immune rejection, but CIRM supports studies designed to provide data to give the best estimate possible.
Is there any research on using stem cells to increase the length of long bones in people?” For example, injecting stem cells into the growth plates to see if the cells can be used to lengthen limbs.Sajid
Dr. Kelly Shepard: There is quite a lot of ongoing research seeking ways to repair bones with stem cell based approaches, which is not the same but somewhat related. Much of this is geared towards repairing the types of bone injuries that do not heal well naturally on their own (large gaps, dead bone lesions, degenerative bone conditions). Also, a lot of this research involves engineering bone tissues in the lab and introducing the engineered tissue into a bone lesion that need be repaired. What occurs naturally at the growth plate is a complex interaction between many different cell types, much of which we do not fully understand. We do not fully understand how to use the cells that are used to engineer bone tissue in the lab. However, a group at Stanford, with some CIRM support, recently discovered a “skeletal stem cell” that exists naturally at the ends of human bones and at sites of fracture. These are quite different than MSCs and offer a new path to be explored for repairing and generating bone.
At CIRM we are privileged to work with many remarkable people who combine brilliance, compassion and commitment to their search for new therapies to help people in need. One of those who certainly fits that description is UC Davis’ Jan Nolta.
This week the UC Davis Newsroom posted a great interview with Jan. Rather than try and summarize what she says I thought it would be better to let her talk for herself.
Talking research, unscrupulous clinics, and sustaining the momentum
In 2007, Jan Nolta
returned to Northern California from St. Louis to lead what was at the
time UC Davis’ brand-new stem cell program. As director of the UC Davis Stem Cell Program
and the Institute for Regenerative Cures, she has overseen the opening
of the institute, more than $140 million in research grants, and dozens
upon dozens of research studies. She recently sat down to answer some
questions about regenerative medicine and all the work taking place at UC Davis Health.
Q: Turning stem cells into cures has been your mission and mantra since you founded the program. Can you give us some examples of the most promising research?
I am so excited about our research. We have about 20 different disease-focused teams.
That includes physicians, nurses, health care staff, researchers and
faculty members, all working to go from the laboratory bench to
patient’s bedside with therapies.
Perhaps the most promising and
exciting research right now comes from combining blood-forming
stem cells with gene therapy. We’re working in about
eight areas right now, and the first cure, something that we definitely
can call a stem cell “cure,” is coming from this combined approach.
doctors will be able to prescribe this type of stem cell therapy.
Patients will use their own bone marrow or umbilical cord stem cells.
Teams such as ours, working in good manufacturing practice
facilities, will make vectors, essentially “biological delivery
vehicles,” carrying a good copy of the broken gene. They will be
reinserted into a patient’s cells and then infused back into the
patient, much like a bone marrow transplant.
“Perhaps the most promising and exciting research right now comes from combining blood-forming stem cells with gene therapy.”
Along with treating the famous bubble baby disease,
where I had started my career, this approach looks very promising for
sickle cell anemia. We’re hoping to use it to treat several different
inherited metabolic diseases. These are conditions characterized by an
abnormal build-up of toxic materials in the body’s cells. They interfere
with organ and brain function. It’s caused by just a single enzyme.
Using the combined stem cell gene therapy, we can effectively put a good
copy of the gene for that enzyme back into a patient’s bone marrow stem
cells. Then we do a bone marrow transplantation and bring back a
person’s normal functioning cells.
The beauty of this therapy is
that it can work for the lifetime of a patient. All of the blood cells
circulating in a person’s system would be repaired. It’s the number one
stem cell cure happening right now. Plus, it’s a therapy that won’t be
rejected. These are a patient’s own stem cells. It is just one type of
stem cell, and the first that’s being commercialized to change cells
throughout the body.
Q: Let’s step back for a moment. In 2004, voters approved Proposition 71.
It has funded a majority of the stem cell research here at UC Davis and
throughout California. What’s been the impact of that ballot measure
and how is it benefiting patients?
We have learned so
much about different types of stem cells, and which stem cell will be
most appropriate to treat each type of disease. That’s huge. We had to
first do that before being able to start actual stem cell therapies. CIRM [California Institute for Regenerative Medicine] has funded Alpha Stem Cell Clinics.
We have one of them here at UC Davis and there are only five in the
entire state. These are clinics where the patients can go for
high-quality clinical stem cell trials approved by the FDA
[U.S. Food and Drug Administration]. They don’t need to go to
“unapproved clinics” and spend a lot of money. And they actually
“By the end of this year, we’ll have 50 clinical trials.”
By the end of this year, we’ll have 50 clinical trials [here at UC Davis Health]. There are that many in the works.
Our Alpha Clinic
is right next to the hospital. It’s where we’ll be delivering a lot of
the immunotherapies, gene therapies and other treatments. In fact, I
might even get to personally deliver stem cells to the operating room
for a patient. It will be for a clinical trial involving people who have
broken their hip. It’s exciting because it feels full circle, from
working in the laboratory to bringing stem cells right to the patient’s
We have ongoing clinical trials
for critical limb ischemia, leukemia and, as I mentioned, sickle cell
disease. Our disease teams are conducting stem cell clinical trials
targeting sarcoma, cellular carcinoma, and treatments for dysphasia [a
swallowing disorder], retinopathy [eye condition], Duchenne muscular
dystrophy and HIV. It’s all in the works here at UC Davis Health.
also great potential for therapies to help with renal disease and
kidney transplants. The latter is really exciting because it’s like a
mini bone marrow transplant. A kidney recipient would also get some
blood-forming stem cells from the kidney donor so that they can better
accept the organ and not reject it. It’s a type of stem cell therapy
that could help address the burden of being on a lifelong regime of
immunosuppressant drugs after transplantation.
Q: You and
your colleagues get calls from family members and patients all the
time. They frequently ask about stem cell “miracle” cures. What should
people know about unproven treatments and unregulated stem cell clinics?
That’s a great question.The number one rule is that if
you’re asked to pay money for a stem cell treatment, don’t do it. It’s a
big red flag.
When it comes to advertised therapies: “The number one rule is that if you’re asked to pay money for a stem cell treatment, don’t do it. It’s a big red flag.”
there are unscrupulous people out there in “unapproved clinics” who
prey on desperate people. What they are delivering are probably not even
stem cells. They might inject you with your own fat cells, which
contain very few stem cells. Or they might use treatments that are not
matched to the patient and will be immediately rejected. That’s
dangerous. The FDA is shutting these unregulated clinics down one at a
time. But it’s like “whack-a-mole”: shut one down and another one pops
On the other hand, the Alpha Clinic is part of our
mission is to help the public get to the right therapy, treatment or
clinical trial. The big difference between those who make patients pay
huge sums of money for unregulated and unproven treatments and UC Davis
is that we’re actually using stem cells. We produce them in rigorously
regulated cleanroom facilities. They are certified to contain at least 99% stem cells.
and family members can always call us here. We can refer them to a
genuine and approved clinical trial. If you don’t get stem cells at the
beginning [of the clinical trial] because you’re part of the placebo
group, you can get them later. So it’s not risky. The placebo is just
saline. I know people are very, very desperate. But there are no miracle
cures…yet. Clinical trials, approved by the FDA, are the only way we’re
going to develop effective treatments and cures.
Scientific breakthroughs take a lot of patience and time. How do you and
your colleagues measure progress and stay motivated?
Motivation? “It’s all for the patients.”
all for the patients. There are not good therapies yet for many
disorders. But we’re developing them. Every day brings a triumph.
Measuring progress means treating a patient in a clinical trial, or
developing something in the laboratory, or getting FDA approval. The big
one will be getting biological license approval from the FDA, which
means a doctor can prescribe a stem cell or gene therapy treatment. Then
it can be covered by a patient’s health insurance.
I’m a cancer
survivor myself, and I’m also a heart patient. Our amazing team here at
UC Davis has kept me alive and in great health. So I understand it from
both sides. I understand the desperation of “Where do I go?” and “What
do I do right now?” questions. I also understand the science side of
things. Progress can feel very, very slow. But everything we do here at
the Institute for Regenerative Cures is done with patients in mind, and
We know that each day is so important when you’re watching
a loved one suffer. We attend patient events and are part of things
like Facebook groups, where people really pour their hearts out. We say
to ourselves, “Okay, we must work harder and faster.” That’s our
motivation: It’s all the patients and families that we’re going to help
who keep us working hard.
Battling cancer is always a balancing act. The methods we use – surgery, chemotherapy and radiation – can help remove the tumors but they often come at a price to the patient. In cases where the cancer has spread to the bone the treatments have a limited impact on the disease, but their toxicity can cause devastating problems for the patient. Now, in a CIRM-supported study, researchers at UC Irvine (UCI) have developed a method they say may be able to change that.
Bone metastasis –
where cancer starts in one part of the body, say the breast, but spreads to the
bones – is one of the most common complications of cancer. It can often result
in severe pain, increased risk of fractures and compression
of the spine. Tackling them is difficult because some cancer cells can
alter the environment around bone, accelerating the destruction of healthy bone
cells, and that in turn creates growth factors that stimulate the growth of the
cancer. It is a vicious cycle where one problem fuels the other.
Now researchers at
UCI have developed a method where they combine engineered mesenchymal stem cells (taken from the bone marrow) with
targeting agents. These act like a drug delivery device, offloading
different agents that simultaneously attack the cancer but protect the bone.
In a news release Weian Zhao, lead author of the study, said:
“What’s powerful about this
strategy is that we deliver a combination of both anti-tumor and anti-bone
resorption agents so we can effectively block the vicious circle between
cancers and their bone niche. This is a safe and almost nontoxic treatment
compared to chemotherapy, which often leaves patients with lifelong issues.”
published in the journal EBioMedicine,
has already been shown to be effective in mice. Next, they hope to be able to
do the safety tests to enable them to apply to the Food and Drug Administration
for permission to test it in people.
The team say if this
approach proves effective it might also be used to help treat other bone-related
diseases such as osteoporosis and multiple myeloma.
When you have a great story to tell the best and most effective way to get it out to the widest audience is still the media, both traditional mainstream and new social media. Recently we have seen three great examples of how that can be done and, hopefully, the benefits that can come from it.
First, let’s go old
school. Earlier this month Caroline Chen wrote a wonderful
in-depth article about clinics that are cashing in on a gray area in stem
cell research. The piece, a collaboration between the New Yorker magazine and
ProPublica, focused on the use of amniotic stem cell treatments and the gap
between what the clinics who offer it are claiming it can do, and the reality.
Here’s one paragraph
profiling a Dr. David Greene, who runs a company providing amniotic fluid to
clinics. It’s a fine piece of writing showing how the people behind these
therapies blur the lines between fact and reality, not just about the cells but
also about themselves:
“Greene said that amniotic stem cells derive their healing power from an ability to develop into any kind of tissue, but he failed to mention that mainstream science does not support his claims. He also did not disclose that he lost his license to practice medicine in 2009, after surgeries he botched resulted in several deaths. Instead, he offered glowing statistics: amniotic stem cells could help the heart beat better, “on average by twenty per cent,” he said. “Over eighty-five per cent of patients benefit exceptionally from the treatment.”
backpedals on that claim, saying:
“I don’t claim that this is a treatment. I don’t claim that it cures anything. I don’t claim that it’s a permanent fix. All I discuss is maybe, potentially, people can get some improvements from stem-cell care.”
This week CBS2
TV in Chicago did their own investigative story about how the number of local
clinics offering unproven and unapproved therapies is on the rise. Reporter Pam
Zekman showed how misleading newspaper ads brought in people desperate for
something, anything, to ease their arthritis pain.
She interviewed two
patients who went to one of those clinics, and ended up out of pocket, and out
“They said they would regenerate the cartilage,” Patricia Korona recalled. She paid $4500 for injections in her knee, but the pain continued. Later X-rays were ordered by her orthopedic surgeon.
“He found bone on bone,” Korona said. “No cartilage grew, which tells me it failed; didn’t work.”
John Zapfel paid $14,000 for stem cell injections on each side of his neck and his shoulder. But an MRI taken by his current doctor showed no improvement.
“They ripped me off, and I was mad.” Zapfel said.
TV and print reports
like this are a great way to highlight the bogus claims made by many of these
clinics, and to shine a light on how they use hype to sell hope to people who
are in pain and looking for help.
At a time when
journalism seems to be increasingly under attack with accusations of “fake news”
it’s encouraging to see reporters like these taking the time and news outlets
devoting the resources to uncover shady practices and protect vulnerable
But the news isn’t
all bad, and the use of social media can help highlight the good news.
That’s what happened
yesterday in our latest CIRM
Facebook Live “Ask the Stem Cell Team” event. The event focused on the
future of stem cell research but also included a really thoughtful look at the
progress that’s been made over the last 10-15 years.
We had two great
guests, UC Davis stem cell researcher and one of the leading bloggers on the
field, Paul Knoepfler PhD; and David
Higgins, PhD, a scientist, member of the CIRM Board and a Patient Advocate
for Huntington’s Disease. They were able to highlight the challenges of the
early years of stem cell research, both globally and here at CIRM, and show how
the field has evolved at a remarkable rate in recent years.
subject of the “bogus clinics” came up – Paul has become a national expert on
these clinics and is quoted in the New Yorker article – as did the subject of
the frustration some people feel at what they consider to be the too-slow pace
of progress. As David Higgins noted, we all think it’s too slow, but we are not
going to race recklessly ahead in search of something that might heal if we
might also end up doing something that might kill.
A portion of the
discussion focused on funding and, in particular, what happens if CIRM is no
longer around to fund the most promising research in California. We are due to
run out of funding for new projects by the end of this year, and without a
re-infusion of funds we will be pretty much closing our doors by the end of
2020. Both Paul and David felt that could be disastrous for the field here in
California, depriving the most promising projects of support at a time when
they needed it most.
It’s probably not
too surprising that three people so closely connected to CIRM (Paul has
received funding from us in the past) would conclude that CIRM is needed for
stem cell research to not just survive but thrive in California.
A word of caution
before you watch: fashion conscious people may be appalled at how my pocket handkerchief
took on a life of its own.
It’s not often you read the word “sensational” in a news release about stem cells. But this week researchers at the University of Copenhagen released findings that are overturning long-held ideas about the development of cells in our stomachs. So perhaps calling it “sensational” is not too big a stretch.
In the past it was believed that the development of immature cells in our stomachs, before a baby is born, was predetermined, that the cells had some kind of innate sense of what they were going to become and when. Turns out that’s not the case. The researchers say it’s the cells’ environment that determines what they will become and that all cells in the fetus’ gut have the potential to turn into stem cells.
In the “sensational” news
release lead author, Kim Jensen, says this
finding could help in the development of new therapies.
“We used to believe that a cell’s
potential for becoming a stem cell was predetermined, but our new results show
that all immature cells have the same probability for becoming stem cells in
the fully developed organ. In principle, it is simply a matter of being in the
right place at the right time. Here signals from the cells’ surroundings
determine their fate. If we are able to identify the signals that are necessary
for the immature cell to develop into a stem cell, it will be easier for us to
manipulate cells in the wanted direction’.
It’s long been known that some lizards and other mammals can
regrow severed limbs, but it hasn’t been clear how. Now scientists at the
University of Cambridge in the UK have figured out what’s going on.
genomics the scientists were able to track which genes are turned on and
off at particular times, allowing them to watch what happens inside the tail of
the African clawed frog tadpole as it regenerates the damaged limb.
They found that the response was orchestrated by a group of
skin cells they called Regeneration-Organizing
Cells, or ROCs. Can Aztekin, one of the lead authors of the study in the
journal Science, says seeing how ROCs work could lead
to new ideas on how to stimulate similar regeneration in other mammals.
“It’s an astonishing process to
watch unfold. After tail amputation, ROCs migrate from the body to the wound
and secrete a cocktail of growth factors that coordinate the response of tissue
precursor cells. These cells then work together to regenerate a tail of the
right size, pattern and cell composition.”
Orphan Drug Designation for CIRM-funded
Poseida Therapeutics got some good news recently about their CIRM-funded therapy for multiple myeloma. The US Food and Drug Administration (FDA) granted them orphan drug designation.
drug designation is given to therapies targeting rare diseases or disorders
that affect fewer than 200,000 people in the U.S. It means the company may be
eligible for grant funding toward clinical trial costs, tax
advantages, FDA user-fee benefits and seven years of market
exclusivity in the United States following marketing approval by
is seeking to destroy these cancerous myeloma cells with an immunotherapy
approach that uses the patient’s own engineered immune system T cells to seek
and destroy the myeloma cells.”
CEO, Eric Ostertag, said the designation is an important milestone for the
company therapy which “has
demonstrated outstanding potency, with strikingly low rates of toxicity in our
phase 1 clinical trial. In fact, the FDA has approved fully outpatient dosing
in our Phase 2 trial starting in the second quarter of 2019.”
Do we know how to pick ‘em or what? For a number of years now we have been funding the work of Stanford’s Dr. Marius Wernig, who is doing groundbreaking work in helping advance stem cell research. Just how groundbreaking was emphasized this week when he was named as the winner of the 2018 Ogawa-Yamanaka Stem Cell Prize.
Marius Wernig, MD, PhD. [Photo: Stanford University]
The prestigious award, from San Francisco’s Gladstone Institutes, honors Wernig for his innovative work in developing a faster, more direct method of turning ordinary cells into, for example, brain cells, and for his work advancing the development of disease models for diseases of the brain and skin disorders.
Dr. Deepak Srivastava, the President of Gladstone, announced the award in a news release:
“Dr. Wernig is a leader in his field with extraordinary accomplishments in stem cell reprogramming. His team was the first to develop neuronal cells reprogrammed directly from skin cells. He is now investigating therapeutic gene targeting and cell transplantation–based strategies for diseases with mutations in a single gene.”
Wernig was understandably delighted at the news:
“It is a great honor to receive this esteemed prize. My lab’s goal is to discover novel biology using reprogrammed cells that aids in the development of effective treatments.”
Wernig will be presented with the award, and a check for $150,000, at a ceremony on Oct. 15 at the Gladstone Institutes in San Francisco.
A stem cell trifecta for teeth research
It was a tooth trifecta among stem cell scientists this week. At Tufts University School of Medicine, researchers made an important advance in the development of bioengineered teeth. The current standard for tooth replacement is a dental implant. This screw-shaped device acts as an artificial tooth root that’s inserted into the jawbone. Implants have been used for 30 years and though successful they can lead to implant failure since they lack many of the properties of natural teeth. By implanting postnatal dental cells along with a gel material into mice, the team demonstrated, in a Journal of Dental Research report, the development of natural tooth buds. As explained in Dentistry Today, these teeth “include features resembling natural tooth buds such as the dental epithelial stem cell niche, enamel knot signaling centers, transient amplifying cells, and mineralized dental tissue formation.”
Another challenge with the development of a bioengineered tooth replacement is reestablishing nerve connections within the tooth, which plays a critical role in its function and protection but doesn’t occur spontaneously after an injury. A research team across the “Pond” at the French National Institute of Health and Medical Research, showed that bone marrow-derived mesenchymal stem cells in the presence of a nerve fiber can help the nerve cells make connections with bioengineered teeth. The study was also published in the Journal of Dental Research.
And finally, a research report about stem cells and the dreaded root canal. When the living soft tissue, or dental pulp, of a tooth becomes infected, the primary course of action is the removal of that tissue via a root canal. The big downside to this procedure is that it leaves the patient with a dead tooth which can be susceptible to future infections. To combat this side effect, researchers at the New Jersey Institute of Technology report the development of a potential remedy: a gel containing a fragment of a protein that stimulates the growth of new blood vessels as well as a fragment of a protein that spurs dental stem cells to divide and grow. Though this technology is still at an early stage, it promises to help keep teeth alive and healthy after root canal. The study was presented this week at the National Meeting of the American Chemical Society.
Here’s an animated video that helps explain the research:
A new study published in STEM CELLS, conducted by researchers at the University of Amsterdam, shows how mesenchymal stem cells (MSCs) can restore the health and improve the function of the immune system, which could benefit the treatment of sepsis. Sepsis is a life-threatening complication from an infection that can lead to multiple organ failure. It is a major cause of illness and death worldwide and despite the use of antibiotics it kills about one in every four patients who contract it.
Since early studies done on animals have shown that treating sepsis with MSCs can reduce the mortality rate by as much as 73 percent, a group of researchers from University of Amsterdam sought to answer this question: could humans realize the same benefits?
So, the team conducted an experiment by taking a group of healthy volunteers and inducing endotoxemia in them, where bacterial toxins can build up and cause fever, nausea and vomiting but do not cause long-term harm to the participants (?). The idea was that by inducing endotoxemia, which exhibits some of the key characteristics of sepsis, that they could model the condition in people.
One hour prior to the initial dose, each person was given an infusion of either adipose (fat) mesenchymal stem cells (ACSs) taken from a donor, or a placebo as a control. Those receiving the ASCs were divided into three groups, with each group receiving a consecutively higher dose of cells.
In a news release, Desiree Perlee, senior author of the study, said the study provided some valuable insights and information:
“The results showed that the ASCs were well tolerated…We realize that there is a limitation with the endotoxemia model. Although in a qualitative way it resembles responses seen in patients with sepsis, it differs in that sepsis-associated alterations are more severe and sustained, while in the endotoxemia model responses occur in a very rapid, short-lived and transient way. But despite these limitations, some of our findings confirm the earlier studies on animals. We believe they show further testing of ASCs in actual sepsis patients is warranted.”
Dr. Jan Nolta, Editor-in-Chief of STEM CELLS (and a CIRM-grantee), said, “This novel clinical trial provides important insight into the mechanism of action of MSCs in inflammation and provides human safety data in support of treatment of sepsis using MSCs.
When I give an “Intro to Stem Cells” presentation to, say, high school students or to a local Rotary Club, I begin by explaining that there are three main types of stem cells: (1) embryonic stem cells (ESCs) (2) adult stem cells and (3) induced pluripotent stem cells (iPSCs). Well, like most things in science, it’s actually not that simple.
To delve a little deeper into the details of characterizing stem cells, I recommend checking out a video animation produced by BioInformant, a stem cell market research company. The video is introduced in a blog, “Do you know the 5 types of stem cells?” by Cade Hildreth, BioInformant’s founder and president.
Image credit: BioInformant
Hildreth’s list categorizes stem cells by the extent of each type’s shape-shifting abilities. So while we sometimes place ESCs and iPSCs in different buckets because the methods for obtaining them are very different, in this list, they both belong to the pluripotent stem cell type. Pluri (“many”) – potent (“potential”) refers to the ability of both stem cell types to specialize into all of the cell types in the body. They can’t, though, make the cells of the placenta and other extra-embryonic cells too. Those ultimate blank-slate stem cells are called toti (“total”) – potent (“potential”).
When it comes to describing adult stem cells in my talks, I often lump blood stem cells together with muscle stem cells because they are stem cells that are present within us throughout life. But based on their ability to mature into specialized cells, these two stem cell types fall into two different categories in Hildreth’s list: blood stem cells which can specialize into closely related cell types – the various cell types found in the blood – are considered “oligopotent” while muscle stem cells are “unipotent” because the can only mature into one type of cell, a muscle cell.
For more details on the five types of stem cells based on their potential to specialize, head over to the BioInformant blog. And scroll to the very bottom for the video animation which can also viewed on FaceBook.
We usually think that starving something of oxygen is going to make it weaker and maybe even kill it. But a new study by J. Kent Leach at UC Davis shows that instead of weakening bone defects, depriving them of oxygen might help boost their ability to create new bone or repair existing bone.
Leach says in the past the use of stem cells to repair damaged or defective bone had limited success because the stem cells often didn’t engraft in the bone or survive long if they did. That was because the cells were being placed in an environment that lacked oxygen (concentration levels in bone range from 3% to 8%) so the cells found it hard to survive.
However, studies in the lab had shown that if you preconditioned mesenchymal stem cells (MSCs), by exposing them to low oxygen levels before you placed them on the injury site, you helped prolong their viability. That was further enhanced by forming the MSCs into three dimensional clumps called spheroids.
Lightbulb goes off
In the current study, published in Stem Cells, Leach says the earlier spheroid results gave him an idea:
“We hypothesized that preconditioning MSCs in hypoxic (low oxygen) culture before spheroid formation would increase cell viability, proangiogenic potential (ability to create new blood vessels), and resultant bone repair compared with that of individual MSCs.”
So, the researchers placed one group of human MSCs, taken from bone marrow, in a dish with just 1% oxygen, and another identical group of MSCs in a dish with normal oxygen levels. After three days both groups were formed into spheroids and placed in an alginate hydrogel, a biopolymer derived from brown seaweed that is often used to build cellular cultures.
The team found that the oxygen-starved cells lasted longer than the ones left in normal oxygen, and the longer those cells were deprived of oxygen the better they did.
Theory is great, how does it work in practice?
Next was to see how those two groups did in actually repairing bones in rats. Leach says the results were encouraging:
“Once again, the oxygen-deprived, spheroid-containing gels induced significantly more bone healing than did gels containing either preconditioned individual MSCs or acellular gels.”
The team say this shows the use of these oxygen-starved cells could be an effective approach to repairing hard-to-heal bone injuries in people.
“Short‐term exposure to low oxygen primes MSCs for survival and initiates angiogenesis (the development of new blood vessels). Furthermore, these pathways are sustained through cell‐cell signaling following spheroid formation. Hypoxic (low oxygen) preconditioning of MSCs, in synergy with transplantation of cells as spheroids, should be considered for cell‐based therapies to promote cell survival, angiogenesis, and bone formation.”
CIRM & Dr. Leach
While CIRM did not fund this study we have invested more than $1.8 million in another study Dr. Leach is doing to develop a new kind of imaging technology that will help us see more clearly what is happening in bone and cartilage-targeted therapies.
In addition, back in March of 2012, Dr. Leach spoke to the CIRM Board about his work developing new approaches to growing bone.