Despite advances in treatments in recent years heart disease remains the leading cause of death in the US. It accounts for one in three deaths in this country, and many people are not even aware they have a problem until they have a heart attack.
One of the early warning signs of danger is a heart arrhythmia; that’s when electrical signals that control the hearts beating don’t work properly and can result in the heart beating too fast, too slow, or irregularly. However, predicting who is at risk of these arrhythmias is difficult. Now new research may have found a way to change that.
A research team at the Institute of Molecular and Cell Biology in Singapore combined stem cells with machine learning, and developed a way to predict arrhythmias, with a high degree of accuracy.
The team used stem cells to create different batches of cardiomyocytes or heart muscle cells. Some of these batches were healthy heart cells, but some had arrhythmias caused by different problems such as a genetic disorder or drug induced.
They then trained a machine learning program to use videos to scan the 3,000 different groups of cells. By studying the different beating patterns of the cells, and then using the levels of calcium in the cells, the machine was able to predict, with 90 percent accuracy, which cells were most likely to experience arrhythmias.
The researchers say their approach is faster, simpler and more accurate than current methods of trying to predict who is at risk for arrhythmias and could have a big impact on our ability to intervene before the individual suffers a fatal heart attack.
The California Institute for Regenerative Medicine has invested more than $180 million in more than 80 different projects, including four clinical trials, targeting heart disease.
Researchers are working on a stem cell-based retinal implant that could be used for people with with advanced dry age-related macular degeneration. (Photo/
Britney O. Pennington)
When Anna Kuehl began losing her vision, she feared losing the ability to read and go on long walks in nature—two of her favorite pastimes. Anna had been diagnosed with age-related macular degeneration, the leading cause of vision loss in the US. She lost the central vision in her left eye, which meant she could no longer make out people’s faces clearly, drive a car, or read the time on her watch.
The treatment sprang out of research done by Dr. Mark Humayun and his team at USC. In collaboration with Regenerative Patch Technologies they developed a stem cell-derived implant using cells from a healthy donor. The implant was then placed under the retina in the back of the eye. The hope was those stem cells would then repair and replace damaged cells and restore some vision.
Dr. Mark Humayun, photo courtesy USC
In the past, using donor cells meant that patients often had to be given long-term immunosuppression to stop their body’s immune system attacking and destroying the patch. But in this trial, the patients were given just two months of immunosuppression, shortly before and after the implant procedure.
In a news story on the USC website, Dr. Humayun said this was an important advantage. “There’s been some debate on whether stem cells derived from a different, unrelated person would survive in the retina without long-term immunosuppression. For instance, if you were to receive a kidney transplant, long-term immunosuppression would be required to prevent organ rejection. This study indicates the cells on the retinal implant can survive for up to two years without long-term immunosuppression.”
Cells show staying power
When one of the patients in the clinical trial died from unrelated causes two years after getting the implant, the research team were able to show that even with only limited immunosuppression, there was no evidence that the patient’s body was rejecting the donor cells.
“These findings show the implant can improve visual function in some patients who were legally-blind before treatment and that the cells on the implant survive and remain functional for at least two years despite not being matched with those of the patient,” Humayun said.
For Anna Kuehl, the results have been remarkable. She was able to read an additional 17 letters on a standard eye chart. Even more importantly, she is able to read again, and able to walk and enjoy nature again.
Dr. Humayun says the study—published in the journal Stem Cell Reports—may have implications for treating other vision-destroying diseases. “This study addresses the debate over the viability of using mismatched stem cells — this shows that a mismatched stem cell derived implant can be safe and viable over multiple years.”
When the COVID pandemic broke out researchers all over the world scrambled to find new approaches to tackling the virus. Some of these, such as the vaccines, proved remarkably effective. Others, such as the anti-parasite medication ivermectin or the anti-malaria drug chloroquine, were not only not helpful, they were sometimes harmful.
Part of the problem was the understandable desire to find something, anything that would protect people from the virus. But another part of the problem was that even with research that was based on solid science, the reporting of that research in the media sometimes tilted towards hype rather than hard evidence.
A new study in the journal Stem Cell Reports takes a look at the explosion of research targeting COVID. They highlighted the lack of rigor that sometimes accompanied that research, and the lack of regulation that allowed some predatory clinics to offer stem cell “therapies” that had never been tested in people let alone shown to be either safe or effective.
Dr. Leigh Turner, from the University of California Irvine and a co-author of the study, warned against studies that were cutting ethical and scientific corners. “Scientists, regulators, and policymakers must guard against the proliferation of poorly designed, underpowered, and duplicative studies that are launched with undue haste because of the pandemic, but are unlikely to provide convincing, clinically meaningful safety and efficacy data.”
The researchers cited an earlier study (by UC Davis’ Dr. Paul Knoepfler and Dr. Mina Kim) that looked at 70 clinical trials involving cell-based treatments for COVID-19. Drs. Knoepfler and Kim found that most were small, involving around 50 patients, and only 22.8% were randomized, double-blinded, and controlled experiments. They say even if these produced promising results they would have to be tested in much larger numbers to be of real benefit.
Another issue that Turner and his team highlighted was the hype that sometimes accompanied this work, citing news releases that over-hyped findings and failed to mention study limitations to gain more media coverage.
In a news releaseDr. Laertis Ikonomou, of the University at Buffalo and a co-author of the study, said over-hyping treatments is nothing new but that it seemed to become even more common during COVID.
“Therefore, it is even more important to communicate promising developments in COVID-19-related science and clinical management [responsibly]. Key features of good communication are an accurate understanding of new findings, including study limitations and avoidance of sensationalist language.”
“Realistic time frames for clinical translation are equally important as is the realization that promising interventions at preliminary stages may not always translate to proven treatments following rigorous testing.”
They also warned about clinics advertising “stem cell therapies” that were unproven and unlicensed and often involved injecting the patients’ own cells back into them. The researchers say it’s time that the FDA and other authorities cracked down on companies taking advantage of patients in this way.
“If companies and affiliated clinicians are not fined, forced to return to patients whatever profits they have made, confronted with criminal charges, subject to revocation of medical licensure, or otherwise subject to serious legal and financial consequences, it is possible that more businesses will be drawn to this space because of the profits that can be generated from selling unlicensed and unproven cell-based products in the midst of a pandemic.”
At a time when so many were dying or suffering long-term health problems as a result of COVID, it’s unconscionable that others were happy to cash in on the fear and pain to make a quick buck.
When the pandemic broke out the CIRM Board voted to approved $5 million in emergency funding to help develop new therapies to combat the virus. Altogether we funded 17 different projects including three clinical trials.
You can’t fix a global problem at the local level. That’s the gist of a new perspective piece in the journal Stem Cell Reports that calls for a global approach to rogue stem cell clinics that offer bogus therapies.
The authors of the article are calling on the World Health Organization (WHO) to set up an advisory committee to draw up rules and regulations to help guide countries trying to shut these clinics down.
In a news release, senior author Mohamed Abou-el-Enein, the executive director of the joint University of Southern California/Children’s Hospital of Los Angeles Cell Therapy Program, says these clinics are trying to cash in on the promise of regenerative medicine.
“Starting in the early 2000s… unregulated stem cell clinics offering untested and poorly characterized treatments with insufficient information on their safety and efficacy began emerging all over the world, taking advantage of the media hype around stem cells and patients’ hope and desperation.”
Dr. Larry Goldstein
The authors include Lawrence Goldstein, PhD, a CIRM Board member and a Science Policy Fellows for the International Society for Stem Cell Research (ISSCR).
Zubin Master, an associate professor of biomedical ethics at the Mayo Clinic, says the clinics prey on vulnerable people who have serious medical conditions and who have often tried conventional medical approaches without success.
“We should aim to develop pathways to provide patients with evidenced-based experimental regenerative intervention as possible options where there is oversight, especially in circumstances where there is no suitable alternative left.”
The report says: “The unproven SCI (stem cell intervention) industry threatens the advancement of regenerative medicine. Reports of adverse events from unproven SCIs has the potential to affect funding and clinical trial recruitment, as well as increasing burdens among regulatory agencies to oversee the industry.
Permitting unregulated SCIs to flourish demonstrates a lack of concern over patient welfare and undermines the need for scientific evidence for medicinal product R&D. While some regulatory agencies have limited oversight or enforcement powers, or choose not to use them, unproven SCI clinics still serve to undermine authority given to regulatory agencies and may reduce public trust impacting the development of safe and effective therapies. Addressing the continued proliferation of clinics offering unproven SCIs is a problem worth addressing now.”
The authors say the WHO is uniquely positioned to help create a framework for the field that can help address these issues. They recommend setting up an advisory committee to develop global standards for regulations governing these clinics that could be applied in all countries. They also say we need more educational materials to let physicians as well as patients understand the health risks posed by bogus clinics.
This article comes out in the same week that reports by the Pew Charitable Trust and the FDA also called for greater regulation of these predatory clinics (we blogged about that here). Clearly there is growing recognition both in the US and worldwide that these clinics pose a threat not just to the health and safety of patients, but also to the reputation of the field of regenerative medicine as a whole.
“I believe that the global spread of unproven stem cell therapies reflects critical gaps in the international system for responding to health crises, which could put the life of thousands of patients in danger,” Abou-el-Enein says. “Urgent measures are needed to enhance the global regulatory capacity to detect and respond to this eminent crisis rapidly.”
It’s hard enough trying to follow the movements of individuals in a crowd of people but imagine how much harder it is to follow the movements of stem cells, crowded into a tiny petri dish. Well, researchers at the Gladstone Institutes in San Francisco have done just that.
In a CIRM-funded study ($5.85M) Dr. Todd McDevitt and his team created a super smart artificial intelligence way of tracking the movements of hundreds of stem cells growing together in a colony, and even identify “leaders” in the pack.
In our bodies groups of stem cells are able to move in specific ways to form different organs and tissues when exposed to the right environment. Unfortunately, we are still trying to learn what “the right environment” is for different organs.
In a news release, McDevitt, the senior author of the paper published in the journal Stem Cell Reports, says this method of observing cells may help us better understand that.
“If I wanted to make a new human heart right now, I know what types of cells are needed, and I know how to grow them independently in dishes. But we really don’t know how to get those cells to come together to form something as complex as a heart. To accomplish that, we need more insights into how cells work cooperatively to arrange themselves.”
Normally scientists watch cells by tagging them with a fluorescent marker so they can see them under a microscope. But this is slow, painstaking work and not particularly accurate. This new method used a series of what are called “neural networks”, which are artificial intelligence (AI) programs that can detect patterns in the movements of the cells. When combined together the networks proved to be able to track the movement of 95 percent of the cells. Humans by comparison can only manage up to 90 percent. But the nets were not only sharper, they were also faster, much faster, some 500 times faster.
This enhanced ability to watch the cells showed that instead of being static most of the time, as had previously been thought, they were actually on the move a lot of the time. They would move around for 15 minutes and then take a breather for ten minutes (time for the stem cell equivalent of a cup of tea perhaps).
Some cells moved around a lot in one direction, while others just seemed to shuffle around in the same area. Some cells even seemed to act as “leaders” while other cells appeared to be “followers” and shuffle along behind them.
None of this would have been visible without the power of the AI networks and McDevitt says being able to tap into this could help researchers better understand how to use these complex movements.
“This technique gives us a much more comprehensive view of how cells behave, how they work cooperatively, and how they come together in physical space to form complex organs.
Follow the Leader is not just a kids’ game anymore. Now it’s a scientific undertaking.
Astrocytes, which provide structural support and protection for neurons and also supply them with nutrients and oxygen.
Bipolar disorder (BPD) is a mental disorder that causes unusual shifts in mood, energy, activity levels, concentration, and the ability to carry out day-to-day tasks. In the United States, recent research has shown that 1.6% of the population has BPD, which is roughly over 4 million people. Those with BPD are more likely to have conditions associated with chronic inflammation such as hypertension and diabetes. It is because of this that scientists have been studying the connection between inflammation and BPD for quite some time.
In a new study, researchers at the Salk Institute for Biological Studies, UC San Diego, and the Institute of Psychiatry and Neuroscience of Paris have found evidence that astrocytes, a certain type of brain cell, can trigger inflammation more easily in those that have BPD. What’s more, these astrocytes can be linked to decreased brain activity that could be harmful to mental health.
Astrocytes are star shaped (as the word “astro” might suggest) and help support neurons, the cells that relay information around the brain. One of these supporting roles includes helping trigger inflammation in the brain and the surrounding nervous system to help with injury or infection. The researchers believe that this process can go wrong in people with BPD and that astrocytes can play a role in this dysfunctional inflammation.
For this study, the team used induced pluripotent stem cells (iPSCs), a kind of stem cell that can turn into virtually any type of cell, that they created from patients with BPD and patients without BPD. They converted these iPSCs into astrocytes and compared those that came from BPD patients to those that did not. What they found is that the astrocytes from patients with BPD were noticeably different. The BPD astrocytes had a higher expression of a protein that triggers an inflammatory response when compared to the non-BPD astrocytes. When they exposed neurons to the BPD astrocytes, the team saw decreased levels of neural activity compared to the non-BPD astrocytes. Lastly, when the researchers blocked the inflammatory protein, the neurons were less affected by the BPD astrocytes.
“Our study suggests that normal function of astrocytes is affected in bipolar disorder patients’ brains, contributing to neuroinflammation,” said Dr. Renata Santos, a researcher at the Salk Institute as well as the Institute of Psychiatry and Neuroscience of Paris, in a news release.
The team hopes that their findings can not only provide insight into BPD, but to other mental illnesses linked to inflammation such as schizophrenia. The ultimate goal is to help advance research into astrocytes and inflammation in order to develop treatments that might reverse the harmful bodily changes seen in those with BPD and other mental disorders.
The full study was published in Stem Cell Reports.
Close-up of the arm of a 70-year-old male patient with a torn biceps muscle as a result of a bowling injury; Photo courtesy Science Photo Library
In the time of coronavirus an awful lot of people are not just working from home they’re also working out at home. That’s a good thing; exercise is a great way to boost the immune system, stay healthy and deal with stress. But for people used to more structured workouts at the gym it can come with a downside. Trying new routines at home that look easy on YouTube, but are harder in practice could potentially increase the risk of injury.
A new study from Japan looks at what happens when you damage a muscle. It won’t help it heal faster, but it will at least let you understand what is happening inside your body as you sit there with ice on your arm and ibuprofen in your hand.
The researchers found that when you damage a muscle, for example by trying to lift too much weight or doing too many repetitions of one exercise, the damaged muscle fibers leak substances that activate nearby “satellite” stem cells. These satellite cells then flock to the site of the injury and help repair the muscle.
The team, from Kumamoto University and Nagasaki University in Japan, named the leaking substances “Damaged myofiber-derived factors” (DMDFs) – personally I think “Substances Leaked by Injured Muscles (SLIM) would be a much cooler acronym, but that’s just me. Gaining a deeper understanding of how DMDFs work might help lead to therapies for older people who have fewer satellite muscle cells, and also for conditions like muscular dystrophy and age-related muscular fragility (sarcopenia), where the number and function of satellite cells decreases.
In an article in Science Daily, Professor Yusuke Ono, the leader of the study, says it’s possible that DMDFs play an even greater role in the body:
“In this study, we proposed a new muscle injury-regeneration model. However, the detailed molecular mechanism of how DMDFs activate satellite cells remains an unclear issue for future research. In addition to satellite cell activation, DMDF moonlighting functions are expected to be diverse. Recent studies have shown that skeletal muscle secretes various factors that affect other organs and tissues, such as the brain and fat, into the bloodstream, so it may be possible that DMDFs are involved in the linkage between injured muscle and other organs via blood circulation. We believe that further elucidation of the functions of DMDFs could clarify the pathologies of some muscle diseases and help in the development of new drugs.”
This past week, there has been a lot of mention of CIRM funded studies that really highlight the importance of the work we support and the different disease areas we make an impact on. This includes important research related to rare disease, Type 1 Diabetes (T1D), and heart function. Below is a summary of the promising CIRM-funded studies released this past week for each one of these areas.
Rare Disease
Comparison of normal (left) and Pelizaeus-Merzbacher disease (PMD) brains (right) at age 2.
Pelizaeus-Merzbacher disease (PMD) is a rare genetic condition affecting boys. It can be fatal before 10 years of age and symptoms of the disease include weakness and breathing difficulties. PMD is caused by a disruption in the formation of myelin, a type of insulation around nerve fibers that allows electrical signals in the brain to travel quickly. Without proper signaling, the brain has difficulty communicating with the rest of the body. Despite knowing what causes PMD, it has been difficult to understand why there is a disruption of myelin formation in the first place.
However, in a CIRM-funded study, Dr. David Rowitch, alongside a team of researchers at UCSF, Stanford, and the University of Cambridge, has been developing potential stem cell therapies to reverse or prevent myelin loss in PMD patients.
Two new studies, of which Dr. Rowitch is the primary author, published in Cell Stem Cell, and Stem Cell Reports, respectively report promising progress in using stem cells derived from patients to identify novel PMD drugs and in efforts to treat the disease by directly transplanting neural stem cells into patients’ brains.
In a UCSF press release, Dr. Rowitch talks about the implications of his findings, stating that,
“Together these studies advance the field of stem cell medicine by showing how a drug therapy could benefit myelination and also that neural stem cell transplantation directly into the brains of boys with PMD is safe.”
Type 1 Diabetes
Viacyte, a company that is developing a treatment for Type 1 Diabetes (T1D), announced in a press release that the company presented preliminary data from a CIRM-funded clinical trial that shows promising results. T1D is an autoimmune disease in which the body’s own immune system destroys the cells in the pancreas that make insulin, a hormone that enables our bodies to break down sugar in the blood. CIRM has been funding ViaCyte from it’s very earliest days, investing more than $72 million into the company.
The study uses pancreatic precursor cells, which are derived from stem cells, and implants them into patients in an encapsulation device. The preliminary data showed that the implanted cells, when effectively engrafted, are capable of producing circulating C-peptide, a biomarker for insulin, in patients with T1D. Optimization of the procedure needs to be explored further.
“This is encouraging news,” said Dr. Maria Millan, President and CEO of CIRM. “We are very aware of the major biologic and technical challenges of an implantable cell therapy for Type 1 Diabetes, so this early biologic signal in patients is an important step for the Viacyte program.”
Heart Function
Although various genome studies have uncovered over 500 genetic variants linked to heart function, such as irregular heart rhythms and heart rate, it has been unclear exactly how they influence heart function.
In a CIRM-funded study, Dr. Kelly Frazer and her team at UCSD studied this link further by deriving heart cells from induced pluripotent stem cells. These stem cells were in turn derived from skin samples of seven family members. After conducting extensive genome-wide analysis, the team discovered that many of these genetic variations influence heart function because they affect the binding of a protein called NKX2-5.
In a press release by UCSD, Dr. Frazer elaborated on the important role this protein plays by stating that,
“NKX2-5 binds to many different places in the genome near heart genes, so it makes sense that variation in the factor itself or the DNA to which it binds would affect that function. As a result, we are finding that multiple heart-related traits can share a common mechanism — in this case, differential binding of NKX2-5 due to DNA variants.”
The full results of this study were published in Nature Genetics.
Retina affected by age-related macular degeneration
Age-related macular degeneration (AMD) is the leading cause of vision loss in people over 60. It affects 10 million Americans. That’s more than cataracts and glaucoma combined. The causes of AMD are not known but are believed to involve a mixture of hereditary and environmental factors. There is no treatment for it.
Now, in a
CIRM-funded study, researchers at UC San Diego (UCSD) have used stem cells to
help identify genetic elements that could provide some clues as to the cause,
and maybe give some ideas on how to treat it.
Before we get into what the researchers did let’s take a look at what AMD does. At a basic level it attacks the retina, the thin layer of tissue that lines the back of the eye. The retina receives light, turns it into electrical signals and sends it to the brain which turns it into a visual image.
The disease destroys the macula, the part of the retina that controls our central vision. At first, sight becomes blurred or fuzzy but over time it progresses to the point where central vision is almost completely destroyed.
To try and
understand why this happens the team at UCSD took skin samples from six people
with AMD and, using the iPSC method, turned those cells into the kinds of cell found in the retina. Because
these cells came from people who had AMD they now displayed the same
characteristics as AMD-affected retinal cells. This allowed the researchers to
create what is called a “disease-in-a-dish” model that allowed them to see, in
real time, what is happening in AMD.
They were able to
identify a genetic variant that reduces production of a protein called VEGFA,
which is known to promote the growth of new blood vessels.
In a news release Kelly Frazer, director of the Institute for Genomic Medicine at UCSD and the lead author of the study, said the results were unexpected.
Kelly Frazer, PhD, UC San Diego
“We didn’t start with the VEGFA gene when we went looking for genetic causes of AMD. But we
were surprised to find that with samples from just six people, this genetic
variation clearly emerged as a causal factor.”
Frazer says this
discovery, published in the journal Stem
Cell Reports, could
ultimately lead to new approaches to developing new treatments for AMD.
There are more than 200,000 cases of traumatic brain injury (TBI) in the US every year. The injuries can be devastating, resulting in everything from difficult sleeping to memory loss, depression and severe disability. There is no cure. But this week the SanBio Group had some encouraging news from its Phase 2 STEMTRA clinical trial.
In the trial patients with TBI were given stem cells, derived from the bone marrow of healthy adult donors. When transplanted into the area of injury in the brain, these cells appear to promote recovery by stimulating the brain’s own regenerative ability.
In this trial the cells demonstrated what the company describes as “a statistically significant improvement in their motor function compared to the control group.”
Endometriosis is an often painful condition that is caused when the cells that normally line the inside of the uterus grow outside of it, causing scarring and damaging other tissues. Over time it can result in severe pain, infertility and increase a woman’s risk for ovarian cancer.
There is no effective long-term treatment but now researchers at Northwestern Medicine have developed an approach, using the woman’s own cells, that could help treat the problem.
The researchers took cells from women, turned them into iPS pluripotent stem cells and then converted those into healthy uterine cells. In laboratory tests these cells responded to the progesterone, the hormone that plays a critical role in the uterus.
In a news release, Dr. Serdar Bulun, a senior author of the study, says this opens the way to testing these cells in women:
“This is huge. We’ve opened the door to treating endometriosis. These women with endometriosis start suffering from the disease at a very early age, so we end up seeing young high school girls getting addicted to opioids, which totally destroys their academic potential and social lives.”
A lot of the research we write about on the Stem Cellar focuses on potential treatments or new approaches that show promise. So every once in a while, it’s good to remind ourselves that there are already stem cell treatments that are not just showing promise, they are saving lives.
That is the case with Ja’Ceon Golden. Regular readers of our blog know that Ja’Ceon was diagnosed with Severe Combined Immunodeficiency (SCID) also known as “bubble baby disease” when he was just a few months old. Children born with SCID often die in the first few years of life because they don’t have a functioning immune system and so even a simple infection can prove life-threatening.
Fortunately Ja’Ceon was enrolled in a CIRM-funded clinical trial at UC San Francisco where his own blood stem cells were genetically modified to correct the problem.
Today he is a healthy, happy, thriving young boy. These pictures, taken by his great aunt Dannie Hawkins, including one of him in his Halloween costume, show how quickly he is growing. And all thanks to some amazing researchers, an aunt who wouldn’t give up on him, and the support of CIRM.
The Stem Cellar 