Stem cell therapy for Parkinson’s disease shows promise in monkeys

Tremors, muscle stiffness, shuffling, slow movement, loss of balance. These are all symptoms of Parkinson’s disease (PD), a neurodegenerative disorder that progressively destroys the dopamine-producing neurons in the brain that control movement.

While there is no cure for Parkinson’s disease, there are drugs like Levodopa and procedures like deep brain stimulation that alleviate or improve some Parkinsonian symptoms. What they don’t do, however, is slow or reverse disease progression.

Scientists are still trying to figure out what causes Parkinson’s patients to lose dopaminergic neurons, and when they do, they hope to stop the disease in its early stages before it can cause the debilitating symptoms mentioned above. In the meantime, some researchers see hope for treating Parkinson’s in the form of stem cell therapies that can replace the brain cells that are damaged or lost due to the disease.

Dopaminergic neurons derived from induced pluripotent stem cells. (Xianmin Zeng, Buck Institute)

Promising results in monkeys

This week, a team of Japanese scientists reported in the journal Nature that they treated monkeys with Parkinson’s-like symptoms by transplanting dopaminergic neurons made from human stem cells into their brains. To prevent the monkeys from rejecting the human cells, they were treated with immunosuppressive drugs. These transplanted neurons survived for more than two years without causing negative side effects, like tumor growth, and also improved PD symptoms, making it easier for the monkeys to move around.

The neurons were made from induced pluripotent stem cells (iPSCs), which are stem cells that can become any cell type in the body and are made by transforming mature human cells, like skin, back to an embryonic-like state. The scientists transplanted neurons made from the iPSCs of healthy people and PD patients into the monkeys and saw that both types of neurons survived and functioned properly by producing dopamine in the monkey brains.

Experts in the field spoke to the importance of these findings in an interview with Nature News. Anders Bjorklund, a neuroscientist at Lund University in Sweden, said “it’s addressing a set of critical issues that need to be investigated before one can, with confidence, move to using the cells in humans,” while Lorenz Studer, a stem-cell scientist at the Memorial Sloan Kettering Cancer Center in New York City, said that “there are still issues to work out, such as the number of cells needed in each transplant procedure. But the latest study is ‘a sign that we are ready to move forward.’”

Next stop, human trials

Jun Takahashi

Looking ahead, Jun Takahashi, the senior author on the study, explained that his team hopes to launch a clinical trial testing this iPSC-based therapy by the end of 2018. Instead of developing personalized iPSC therapies for individual PD patients, which can be time consuming and costly, Takahashi plans to make special donor iPSC lines (called human leukocyte antigen or HLA-homozygous iPSCs) that are immunologically compatible with a larger population of patients.

In a separate study published at the same time in Nature Communications, Takahashi and colleagues showed that transplanting neurons derived from immune-matched monkey iPSCs improved their survival and dampened the immune response.

The Nature News article does a great job highlighting the findings and significance of both studies and also mentions other research projects using stem cells to treat PD in clinical trials.

“Earlier this year, Chinese researchers began a Parkinson’s trial that used a different approach: giving patients neural-precursor cells made from embryonic stem cells, which are intended to develop into mature dopamine-producing neurons. A year earlier, in a separate trial, patients in Australia received similar cells. But some researchers have expressed concerns that the immature transplanted cells could develop tumour-causing mutations.

Meanwhile, researchers who are part of a Parkinson’s stem-cell therapy consortium called GForce-PD, of which Takahashi’s team is a member, are set to bring still other approaches to the clinic. Teams in the United States, Sweden and the United Kingdom are all planning trials to transplant dopamine-producing neurons made from embryonic stem cells into humans. Previously established lines of embryonic stem cells have the benefit that they are well studied and can be grown in large quantities, and so all trial participants can receive a standardized treatment.”

You can read more coverage on these research studies in STATnews, The San Diego Union Tribune, and Scientific American.

For a list of projects CIRM is funding on Parkinson’s disease, visit our website.

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New research suggests taking a daily dose of vitamin C could prevent leukemia

Did you take your vitamins today? It’s not always easy to remember with such busy lives, but after you read this blog, you’ll be sure to make vitamins part of your daily routine if you haven’t already!

Two recent studies, published in the journals Nature and Cell, reported that vitamin C has a direct impact on the function of blood forming, or hematopoietic stem cells, and can be used to protect mice from getting a blood cancer called leukemia.

Science reporter Bradley Fikes compared the findings of the two studies yesterday in the San Diego Union Tribune. According to Fikes, the Nature study, which was conducted by scientists at UT Southwestern, “found that human and mouse hematopoietic stem cells absorb unusually large amounts of vitamin C. When the cells were depleted of vitamin C, they were more likely to turn into leukemia cells.”

As for the Cell study, scientists from NYU Langone Health “found that high doses of vitamin C can cause leukemic cells to die, potentially making it a useful and safe chemotherapy agent.” For more details on this particular study, see our blog from last week and the video below.

Dr. Benjamin Neel, director of NYU Langone’s Perlmutter Cancer Center, discusses how vitamin C may “tell” faulty stem cells in the bone marrow to mature and die normally, instead of multiplying to cause blood cancers.

Vitamin C levels are crucial for preventing leukemia

The common factor between the two studies is a gene called Tet2, which is turned on in blood stem cells and protects them from over-proliferating and acquiring genetic mutations that transform them into leukemia cells. If one copy of the Tet2 gene is genetically mutated, treating blood stem cells with vitamin C can make up for this partial loss in Tet2 function. However, if both copies of Tet2 are mutated, its protective functions are completely lost and blood stem cells can turn cancerous.

Fikes reached out to Sean Morrison, senior author on the Nature study, for an explanation about the relationship between vitamin C and Tet2, and how it can be leveraged to prevent or treat leukemia:

Sean Morrison

“The Cell study showed that high doses of vitamin C can compensate for Tet2 mutations, restoring normal function, Morrison said. Usually, transformation of normal cells into leukemic cells is irreversible, but the study demonstrated that’s not true when the leukemia is driven by Tet2 mutations.”

“The Nature study demonstrated that vitamin C is a limiting factor in the proper function of Tet2, Morrison said. People have two copies of the gene, one from each parent. When one of the genes is disabled, it’s important to take the full recommended dose of vitamin C so the remaining gene can exert its full tumor-suppressing effect.”

Before you place your bulk order of vitamin C on amazon, you should be aware that Morrison and his colleagues found that giving mice super doses of the supplement failed to further reduce their risk of getting leukemia. Thus, it seems that having the right levels of vitamin C in blood stem cells and healthy copies of the Tet2 gene are vital for preventing leukemia.

Vitamin C, a panacea for cancer?

These two studies raise important questions. Do vitamin C levels play a role in the development of other cancer cells and could this supplement be used as a treatment for other types of cancers?

Since the 1970’s, scientists (including the famous American scientist Linus Pauling) and doctors have pursued vitamin C as a potential cancer treatment. Early stage research revealed that vitamin C plays a role in slowing the growth of various types of cancer cells including prostate, colon and brain cancer cells. More recently, some of this research has progressed to clinical trials that are testing high-doses of vitamin C either by itself or in combination with chemotherapy drugs in cancer patients. Some of these trials have reported an improved quality of life and increased average survival time in patients, but more research and trials are necessary to determine whether vitamin C is a truly effective anti-cancer therapy.

Now that Morrison and his team have a better understanding of how vitamin C levels affect cancer risk, they plan to address some of these outstanding questions in future studies.

“Our data also suggest that probably not all cancers are increased by vitamin C depletion. We particularly would predict that certain leukemias would be increased in the absence of vitamin C. We’re collaborating with the Centers for Disease Control right now to look more carefully at the epidemiological data that have been collected over decades, to understand more precisely which cancers are at increased risk in people that have lower levels of vitamin C.”

CIRM weekly stem cell roundup: stomach bacteria & cancer; vitamin C may block leukemia; stem cells bring down a 6’2″ 246lb football player

gastric

This is what your stomach glands looks like from the inside:  Credit: MPI for Infection Biology”

Stomach bacteria crank up stem cell renewal, may be link to gastric cancer (Todd Dubnicoff)

The Centers for Disease Control and Prevention estimate that two-thirds of the world’s population is infected with H. pylori, a type of bacteria that thrives in the harsh acidic conditions of the stomach. Data accumulated over the past few decades shows strong evidence that H. pylori infection increases the risk of stomach cancers. The underlying mechanisms of this link have remained unclear. But research published this week in Nature suggests that the bacteria cause stem cells located in the stomach lining to divide more frequently leading to an increased potential for cancerous growth.

Tumors need to make an initial foothold in a tissue in order to grow and spread. But the cells of our stomach lining are replaced every four days. So, how would H. pylori bacterial infection have time to induce a cancer? The research team – a collaboration between scientists at the Max Planck Institute in Berlin and Stanford University – asked that question and found that the bacteria are also able to penetrate down into the stomach glands and infect stem cells whose job it is to continually replenish the stomach lining.

Further analysis in mice revealed that two groups of stem cells exist in the stomach glands – one slowly dividing and one rapidly dividing population. Both stem cell populations respond similarly to an important signaling protein, called Wnt, that sustains stem cell renewal. But the team also discovered a second key stem cell signaling protein called R-spondin that is released by connective tissue underneath the stomach glands. H. pylori infection of these cells causes an increase in R-spondin which shuts down the slowly dividing stem cell population but cranks up the cell division of the rapidly dividing stem cells. First author, Dr. Michal Sigal, summed up in a press release how these results may point to stem cells as the link between bacterial infection and increased risk of stomach cancer:

“Since H. pylori causes life-long infections, the constant increase in stem cell divisions may be enough to explain the increased risk of carcinogenesis observed.”

vitamin-c-1200x630

Vitamin C may have anti-blood cancer properties

Vitamin C is known to have a number of health benefits, from preventing scurvy to limiting the buildup of fatty plaque in your arteries. Now a new study says we might soon be able to add another benefit: it may be able to block the progression of leukemia and other blood cancers.

Researchers at the NYU School of Medicine focused their work on an enzyme called TET2. This is found in hematopoietic stem cells (HSCs), the kind of stem cell typically found in bone marrow. The absence of TET2 is known to keep these HSCs in a pre-leukemic state; in effect priming the body to develop leukemia. The researchers showed that high doses of vitamin C can prevent, or even reverse that, by increasing the activity level of TET2.

In the study, in the journal Cell, they showed how they developed mice that could have their levels of TET2 increased or decreased. They then transplanted bone marrow with low levels of TET2 from those mice into healthy, normal mice. The healthy mice started to develop leukemia-like symptoms. However, when the researchers used high doses of vitamin C to restore the activity levels of TET2, they were able to halt the progression of the leukemia.

Now this doesn’t mean you should run out and get as much vitamin C as you can to help protect you against leukemia. In an article in The Scientist, Benjamin Neel, senior author of the study, says while vitamin C does have health benefits,  consuming large doses won’t do you much good:

“They’re unlikely to be a general anti-cancer therapy, and they really should be understood based on the molecular understanding of the many actions vitamin C has in cells.”

However, Neel says these findings do give scientists a new tool to help them target cells before they become leukemic.

Jordan reed

Bad toe forces Jordan Reed to take a knee: Photo courtesy FanRag Sports

Toeing the line: how unapproved stem cell treatment made matters worse for an NFL player  

American football players are tough. They have to be to withstand pounding tackles by 300lb men wearing pads and a helmet. But it wasn’t a crunching hit that took Washington Redskins player Jordan Reed out of the game; all it took to put the 6’2” 246 lb player on the PUP (Physically Unable to Perform) list was a little stem cell injection.

Reed has had a lingering injury problem with the big toe on his left foot. So, during the off-season, he thought he would take care of the issue, and got a stem cell injection in the toe. It didn’t quite work the way he hoped.

In an interview with the Richmond Times Dispatch he said:

“That kind of flared it up a bit on me. Now I’m just letting it calm down before I get out there. I’ve just gotta take my time, let it heal and strengthen up, then get back out there.”

It’s not clear what kind of stem cells Reed got, if they were his own or from a donor. What is clear is that he is just the latest in a long line of athletes who have turned to stem cells to help repair or speed up recovery from an injury. These are treatments that have not been approved by the Food and Drug Administration (FDA) and that have not been tested in a clinical trial to make sure they are both safe and effective.

In Reed’s case the problem seems to be a relatively minor one; his toe is expected to heal and he should be back in action before too long.

Stem cell researcher and avid blogger Dr. Paul Knoepfler wrote he is lucky, others who take a similar approach may not be:

“Fortunately, it sounds like Reed will be fine, but some people have much worse reactions to unproven stem cells than a sore toe, including blindness and tumors. Be careful out there!”

How mice and zebrafish are unlocking clues to repairing damaged hearts

Bee-Gees

The Bee Gees, pioneers in trying to find ways to mend a broken heart. Photograph: Michael Ochs Archives

This may be the first time that the Australian pop group the Bee Gees have ever been featured in a blog about stem cell research, but in this case I think it’s appropriate. One of the Bee Gees biggest hits was “How can you mend a broken heart” and while it was a fine song, Barry and Robin Gibb (who wrote the song) never really came up with a viable answer.

Happily some researchers at the University of Southern California may succeed where Barry and Robin failed. In a study, published in the journal Nature Genetics, the USC team identify a gene that may help regenerate damaged heart tissue after a heart attack.

When babies are born they have a lot of a heart muscle cell called a mononuclear diploid cardiomyocyte or MNDCM for short. This cell type has powerful regenerative properties and so is able to rebuild heart muscle. However, as we get older we have less and less MNDCMs. By the time most of us are at an age where we are most likely to have a heart attack we are also most likely to have very few of these cells, and so have a limited ability to repair the damage.

Michaela Patterson, and her colleagues at USC, set out to find ways to change that. They found that in some adult mice less than 2 percent of their heart cells were MNDCMs, while other mice had a much higher percentage, around 10 percent. Not surprisingly the mice with the higher percentage of MNDCMs were better able to regenerate heart muscle after a heart attack or other injury.

So the USC team – with a little help from CIRM funding – dug a little deeper and did a genome-wide association study of these mice, that’s where they look at all the genetic variants in different individuals to see if they can spot common traits. They found one gene, Tnni3k, that seems to play a key role in generating MNDCMs.

Turning Tnni3K off in mice resulted in higher numbers of MNDCMs, increasing their ability to regenerate heart muscle. But when they activated Tnni3k in zebrafish it reduced the number of MNDCMs and impaired the fish’s ability to repair heart damage.

While it’s a long way from identifying something interesting in mice and zebrafish to seeing if it can be used to help people, Henry Sucov, the senior author on the study, says these findings represent an important first step in that direction:

“The activity of this gene, Tnni3k, can be modulated by small molecules, which could be developed into prescription drugs in the future. These small molecules could change the composition of the heart over time to contain more of these regenerative cells. This could improve the potential for regeneration in adult hearts, as a preventative strategy for those who may be at risk for heart failure.”

 

 

 

Stem cell stories that caught our eye: skin grafts fight diabetes, reprogramming the immune system, and Asterias expands spinal cord injury trial sites

Here are the stem cell stories that caught our eye this week.

Skin grafts fight diabetes and obesity.

An interesting new gene therapy strategy for fighting type 1 diabetes and obesity surfaced this week. Scientists from the University of Chicago made genetically engineered skin grafts that secrete a peptide hormone called glucagon-liked peptide-1 (GLP-1). This peptide is released by cells in the intestine and can lower blood sugar levels by stimulating pancreatic islet cells to secrete insulin (a hormone that promotes the absorption of glucose from the blood).

The study, which was published in the journal Cell Stem Cell, used CRISPR gene editing technology to introduce a mutation to the GLP-1 gene in mouse and human skin stem cells. This mutation stabilized the GLP-1 peptide, allowing it to hang around in the blood for longer. The team matured these stem cells into skin grafts that secreted the GLP-1 into the bloodstream of mice when treated with a drug called doxycycline.

When fed a high-fat diet, mice with a skin graft (left), genetically altered to secrete GLP-1 in response to the antibiotic doxycycline, gained less weight than normal mice (right). (Image source: Wu Laboratory, the University of Chicago)

On a normal diet, mice that received the skin graft saw a rise in their insulin levels and a decrease in their blood glucose levels, proving that the gene therapy was working. On a high fat diet, mice with the skin graft became obese, but when they were treated with doxycycline, GLP-1 secreted from their grafts reduced the amount of weight gain. So not only does their engineered skin graft technology look like a promising new strategy to treat type 1 diabetes patients, it also could be used to control obesity. The beauty of the technology is in its simplicity.

An article in Genetic Engineering and Biotechnology News that covered this research explained that Xiaoyang Wu, the senior author on the study, and his team “worked with skin because it is a large organ and easily accessible. The cells multiply quickly and are easily transplanted. And, transplanted cells can be removed, if needed. “Skin is such a beautiful system,” Wu says, noting that its features make it a perfect medium for testing gene therapies.”

Wu concluded that, “This kind of therapy could be potentially effective for many metabolic disorders.” According to GenBio, Wu’s team “is now testing the gene-therapy technique in combination with other medications.” They also hope that a similar strategy could be used to treat patients that can’t make certain proteins like in the blood clotting disorder hemophilia.

How to reprogram your immune system (Kevin McCormack)

When your immune system goes wrong it can cause all manner of problems, from type 1 diabetes to multiple sclerosis and cancer. That’s because an overactive immune system causes the body to attack its own tissues, while an underactive one leaves the body vulnerable to outside threats such as viruses. That’s why scientists have long sought ways to correct those immune dysfunctions.

Now researchers at the Gladstone Institutes in San Francisco think they have found a way to reprogram specific cells in the immune system and restore a sense of health and balance to the body. Their findings are published in the journal Nature.

The researchers identified a drug that targets effector T cells, which get our immune system to defend us against outside threats, and turns them into regulatory T cells, which control our immune system and stops it from attacking our own body.

Why would turning one kind of T cell into another be helpful? Well, in some autoimmune diseases, the effector T cells become overly active and attack healthy tissues and organs, damaging and even destroying them. By converting them to regulatory T cells you can prevent that happening.

In addition, some cancers can hijack regulatory T cells and suppress the immune system, allowing the disease to spread. By turning those cells into effector T cells, you can boost the immune system and give it the strength to fight back and, hopefully, kill the cancer.

In a news release, Gladstone Senior Investigator Sheng Ding, the lead scientists on the study, said their findings could have several applications:

“Our findings could have a significant impact on the treatment of autoimmune diseases, as well as on stem cell and immuno-oncology therapies.” 

Gladstone scientists Sheng Ding (right) and Tao Xu (left) discovered how to reprogram cells in our immune system. (Gladstone Institutes)

CIRM-funded spinal cord injury trial expands clinical sites

We have another update from CIRM’s clinical trial front. Asterias Biotherapeutics, which is testing a stem cell treatment for complete cervical (neck) spinal cord injury, is expanding its clinical sites for its CIRM-funded SCiStar Phase 1/2a trial. The company is currently treating patients at six sites in the US, and will be expanding to include two additional sites at Thomas Jefferson University Hospital in Philadelphia and the UC San Diego Medical Center, which is part of the UCSD Health CIRM Alpha Stem Cell Clinic.

In a company news release, Ed Wirth, Chief Medical Officer of Asterias said,

Ed Wirth

“We are excited about the clinical site openings at Thomas Jefferson University Hospital and UC San Diego Health. These sites provide additional geographical reach and previous experience with spinal cord injury trials to our SCiStar study. We have recently reported completion of enrollment in four out of five cohorts in our SCiStar study so we hope these institutions will also participate in a future, larger study of AST-OPC1.”

The news release also gave a recap of the trial’s positive (but still preliminary) results this year and their plans for completing trial enrollment.

“In June 2017, Asterias reported 9 month data from the AIS-A 10 million cell cohort that showed improvements in arm, hand and finger function observed at 3-months and 6-months following administration of AST-OPC1 were confirmed and in some patients further increased at 9-months. The company intends to complete enrollment of the entire SCiStar study later this year, with multiple safety and efficacy readouts anticipated during the remainder of 2017 and 2018.”

Scientists fix heart disease mutation in human embryos using CRISPR

Last week the scientific community was buzzing with the news that US scientists had genetically modified human embryos using CRISPR gene editing technology. While the story broke before the research was published, many journalists and news outlets weighed in on the study’s findings and the ethical implications they raise. We covered this initial burst of news in last week’s stem cell stories that caught our eye.

Shoukhrat Mitalipov (Leah Nash, New York Times)

After a week of suspense, the highly-anticipated study was published yesterday in the journal Nature. The work was led by senior author Dr. Shoukhrat Mitalipov from Oregon Health and Sciences University (and a member of CIRM’s Grants Working Group, the panel of experts who review applications to us for funding) in collaboration with scientists from the Salk Institute and Korea’s Institute for Basic Science.

In brief, the study revealed that the teams’ CRISPR technology could correct a genetic mutation that causes a disease called hypertrophic cardiomyopathy (HCM) in 72% of human embryos without causing off-target effects, which are unwanted genome modifications caused by CRISPR. These findings are a big improvement over previous studies by other groups that had issues with off-target effects and mosaicism, where CRISPR only correctly modifies mutations in some but not all cells in an embryo.

Newly fertilized eggs before gene editing, left, and embryos after gene editing and a few rounds of cell division. (Image from Shoukrat Mitalipov in New York Times)

Mitalipov spoke to STATnews about a particularly interesting discovery that he and the other scientists made in the Nature study,

“The main finding is that the CRISPR’d embryos did not accept the “repair DNA” that the scientists expected them to use as a replacement for the mutated gene deleted by CRISPR, which the embryos inherited from their father. Instead, the embryos used the mother’s version of the gene, called the homologue.”

Sharon Begley, the author of the STATnews article, argued that this discovery means that “designer babies” aren’t just around the corner.

“If embryos resist taking up synthetic DNA after CRISPR has deleted an unwanted gene, then “designer babies,” created by inserting a gene for a desirable trait into an embryo, will likely be more difficult than expected.”

Ed Yong from the Atlantic also took a similar stance towards Mitalipov’s study in his article titled “The Designer Baby Era is Not Upon Us”. He wrote,

“The bigger worry is that gene-editing could be used to make people stronger, smarter, or taller, paving the way for a new eugenics, and widening the already substantial gaps between the wealthy and poor. But many geneticists believe that such a future is fundamentally unlikely because complex traits like height and intelligence are the work of hundreds or thousands of genes, each of which have a tiny effect. The prospect of editing them all is implausible. And since genes are so thoroughly interconnected, it may be impossible to edit one particular trait without also affecting many others.”

Dr. Juan Carlos Izpisua Belmonte, who’s a corresponding author on the paper and a former CIRM grantee from the Salk Institute, commented on the impact that this research could have on human health in a Salk news release.

Co-authors Juan Carlos Izpisua Belmonte and Jun Wu. (Salk Institute)

“Thanks to advances in stem cell technologies and gene editing, we are finally starting to address disease-causing mutations that impact potentially millions of people. Gene editing is still in its infancy so even though this preliminary effort was found to be safe and effective, it is crucial that we continue to proceed with the utmost caution, paying the highest attention to ethical considerations.”

Pam Belluck from The New York Times also suggested that this research could have a significant impact on how we prevent disease in newborns.

“This research marks a major milestone and, while a long way from clinical use, it raises the prospect that gene editing may one day protect babies from a variety of hereditary conditions.”

So when will the dawn of CRISPR babies arrive? Ed Yong took a stab at answering this million dollar question with help from experts in the field.

“Not for a while. The technique would need to be refined, tested on non-human primates, and shown to be safe. “The safety studies would likely take 10 to 15 years before FDA or other regulators would even consider allowing clinical trials,” wrote bioethicist Hank Greely in a piece for Scientific American. “The Mitalipov research could mean that moment is 9 years and 10 months away instead of 10 years, but it is not close.” In the meantime, Mitalipov’s colleague Sanjiv Kaul says, “We’ll get the method to perfection so that when it’s possible to use it in a clinical trial, we can.”

Stem Cell Stories that Caught our Eye: CRISPRing Human Embryos, brain stem cells slow aging & BrainStorm ALS trial joins CIRM Alpha Clinics

Here are the stem cell stories that caught our eye this week. Enjoy!

Scientists claim first CRISPR editing of human embryos in the US.

Here’s the big story this week. Scientists from Portland, Oregon claim they genetically modified human embryos using the CRISPR/Cas9 gene editing technology. While their results have yet to be published in a peer review journal (though the team say they are going to be published in a prominent journal next month), if they prove true, the study will be the first successful attempt to modify human embryos in the US.

A representation of an embryo being fertilized. Scientists can inject CRISPR during fertilization to correct genetic disorders. (Getty Images).

Steve Connor from MIT Technology Review broke the story earlier this week noting that the only reports of human embryo modification were published by Chinese scientists. The China studies revealed troubling findings. CRISPR caused “off-target” effects, a situation where the CRISPR machinery randomly introduces genetic errors in a cell’s DNA, in the embryos. It also caused mosaicism, a condition where the desired DNA sequences aren’t genetically corrected in all the cells of an embryo producing an individual with cells that have different genomes. Putting aside the ethical conundrum of modifying human embryos, these studies suggested that current gene editing technologies weren’t accurate enough to safely modify human embryos.

But a new chapter in human embryo modification is beginning. Shoukhrat Mitalipov (who is a member of CIRM’s Grants Working Group, the panel of scientific experts that reviews our funding applications) and his team from the Oregon Health and Science University said that they have developed a method to successfully modify donated human embryos that avoids the problems experienced by the Chinese scientists. The team found that introducing CRISPR at the same time an embryo was being fertilized led to successful correction of disease-causing mutations while avoiding mosaicism and “off-target” effects. They grew these embryos for a few days to confirm that the genetic modifications had worked before destroying them.

The MIT piece quoted a scientist who knows of Mitalipov’s work,

“It is proof of principle that it can work. They significantly reduced mosaicism. I don’t think it’s the start of clinical trials yet, but it does take it further than anyone has before.”

Does this discovery, if it’s true, open the door further for the creation of designer babies? For discussions about the future scientific and ethical implications of this research, I recommend reading Paul Knoepfler’s blog, this piece by Megan Molteni in Wired Magazine and Jessica Berg’s article in The Conversation.

Brain stem cells slow aging in mice

The quest for eternal youth might be one step closer thanks to a new study published this week in the journal Nature. Scientists from the Albert Einstein College of Medicine in New York discovered that stem cells found in an area of the brain called the hypothalamus can slow the aging process in mice.

The hypothalamus is located smack in the center of your brain near the brain stem. It’s responsible for essential metabolic functions such as making and secreting hormones, managing body temperature and controlling feelings of hunger and thirst. Because the body’s metabolic functions decline with age, scientists have suspected that the hypothalamus plays a role in aging.

The mouse hypothalamus. (NIH, Wikimedia).

In the current study, the team found that stem cells in the hypothalamus gradually disappear as mice age. They were curious whether the disappearance of these stem cells could jump start the aging process. When they removed these stem cells, the mice showed more advanced mental and physical signs of aging compared to untreated mice.

They also conducted the opposite experiment where they transplanted hypothalamic stem cells taken from baby mice (the idea being that these stem cells would exhibit more “youthful” qualities) into the brains of middle-aged mice and saw improvements in mental and physical functions and a 10% increase in lifespan.

So what is it about these specific stem cells that slows down aging? Do they replenish the aging brain with new healthy cells or do they secrete factors that keep the brain healthy? Interestingly, the scientists found that these stem cells secreted vesicles that contained microRNAs, which are molecules that regulate gene expression by turning genes on or off.

They injected these microRNAs into the brains of middle-aged mice and found that they reversed symptoms of aging including cognitive decline and muscle degeneration. Furthermore, when they removed hypothalamic stem cells from middle-aged mice and treated them with the microRNAs, they saw the same anti-aging effects.

In an interview with Nature News, senior author on the study, Dongsheng Cai, commented that hypothalamic stem cells could have multiple ways of regulating aging and that microRNAs are just one of their tools. For this research to translate into an anti-aging therapy, “Cai suspects that anti-ageing therapies targeting the hypothalamus would need to be administered in middle age, before a person’s muscles and metabolism have degenerated beyond a point that could be reversed.”

This study and its “Fountain of Youth” implications has received ample attention from the media. You can read more coverage from The Scientist, GenBio, and the original Albert Einstein press release.

BrainStorm ALS trial joins the CIRM Alpha Clinics

Last month, the CIRM Board approved $15.9 million in funding for BrainStorm Cell Therapeutic’s Phase 3 trial that’s testing a stem cell therapy to treat patients with a devastating neurodegenerative disease called amyotrophic lateral sclerosis or ALS (also known as Lou Gehrig’s disease).

The stem cell therapy, called NurOwn®, is made of mesenchymal stem cells extracted from a patient’s bone marrow. The stem cells are genetically modified to secrete neurotrophic factors that keep neurons in the brain healthy and prevent their destruction by diseases like ALS.

BrainStorm has tested NurOwn in early stage clinical trials in Israel and in a Phase 2 study in the US. These trials revealed that the treatment was “safe and well tolerated” and that “NurOwn also achieved multiple secondary efficacy endpoints, showing clear evidence of a clinically meaningful benefit.  Notably, response rates were higher for NurOwn-treated subjects compared to placebo at all time points in the study out to 24 weeks.”

This week, BrainStorm announced that it will launch its Phase 3 CIRM-funded trial at the UC Irvine (UCI) CIRM Alpha Stem Cell Clinic. The Alpha Clinics are a network of top medical centers in California that specialize in delivering high quality stem cell clinical trials to patients. UCI is one of four medical centers including UCLA, City of Hope, and UCSD, that make up three Alpha Clinics currently supporting 38 stem cell trials in the state.

Along with UCI, BrainStorm’s Phase 3 trial will also be conducted at two other sites in the US: Mass General Hospital in Boston and California Pacific Medical Center in San Francisco. Chaim Lebovits, President and CEO, commented,

“We are privileged to have UCI and Dr. Namita Goyal join our pivotal Phase 3 study of NurOwn. Adding UCI as an enrolling center with Dr. Goyal as Principal Investigator will make the treatment more accessible to patients in California, and we welcome the opportunity to work with this prestigious institution.”

Before the Phase 3 trial can launch at UCI, it needs to be approved by our federal regulatory agency, the Food and Drug Administration (FDA), and an Institutional Review Board (IRB), which is an independent ethics committee that reviews biomedical research on human subjects. Both these steps are required to ensure that a therapy is safe to test in patients.

With promising data from their Phase 1 and 2 trials, BrainStorm’s Phase 3 trial will likely get the green light to move forward. Dr. Goyal, who will lead the trial at the UCI Alpha Clinic, concluded:

“NurOwn is a very promising treatment with compelling Phase 2 data in patients with ALS; we look forward to further advancing it in clinical development and confirming the therapeutic benefit with Brainstorm.”

CIRM-funded life-saving stem cell therapy gets nod of approval from FDA

Cured_AR_2016_coverIf you have read our 2016 Annual Report (and if you haven’t you should, it’s brilliant) or just seen the cover you’ll know that it features very prominently a young girl named Evie Padilla Vaccaro.

Evie was born with Severe Combined Immunodeficiency or SCID – also known as “bubble baby disease”; we’ve written about it here. SCID is a rare but deadly immune disorder which leaves children unable to fight off simple infections. Many children with SCID die in the first few years of life.

Fortunately for Evie and her family, Dr. Don Kohn and his team at UCLA, working with a UK-based company called Orchard Therapeutics Ltd., have developed a treatment called OTL-101. This involves taking the patient’s own blood stem cells, genetically modifying them to correct the SCID mutation, and then returning the cells to the patient. Those modified cells create a new blood supply, and repair the child’s immune system.

Evie was treated with OTL-101 when she was a few months old. She is cured. And she isn’t the only one. To date more than 40 children have been treated with this method. All have survived and are doing well.

Orchard Therapeutics

 FDA acknowledgement

Because of that success the US Food and Drug Administration (FDA) has granted OTL-101 Rare Pediatric Disease Designation. This status is given to a treatment that targets a serious or life-threatening disease that affects less than 200,000 people, most of whom are under 18 years of age.

The importance of the Rare Pediatric Disease Designation is that it gives the company certain incentives for the therapy’s development, including priority review by the FDA. That means if it continues to show it is safe and effective it may have a faster route to being made more widely available to children in need.

In a news release Anne Dupraz, PhD, Orchard’s Chief Regulatory Officer, welcomed the decision:

“Together with Orphan Drug and Breakthrough Therapy Designations, this additional designation is another important development step for the OTL-101 clinical program. It reflects the potential of this gene therapy treatment to address the significant unmet medical need of children with ADA-SCID and eligibility for a Pediatric Disease Priority Review voucher at time of approval.”

Creating a trend

This is the second time in less than two weeks that a CIRM-funded therapy has been awarded Rare Pediatric Disease designation. Earlier this month Capricor Therapeutics was given that status for its treatment for Duchenne Muscular Dystrophy.

Two other CIRM-funded clinical trials – Humacyte and jCyte – have been given Regenerative Medicine Advanced Therapy Designation (RMAT) by the FDA. This makes them eligible for earlier and faster interactions with the FDA, and also means they may be able to apply for priority review and faster approval.

All these are encouraging signs for a couple of reasons. It suggests that the therapies are showing real promise in clinical trials. And it shows that the FDA is taking steps to encourage those therapies to advance as quickly – and safely of course – as possible.

Credit where credit is due

In the past we have been actively critical of the FDA’s sluggish pace in moving stem cell therapies out of the lab and into clinical trials where they can be tested in people. So when the FDA does show signs of changing the way it works it’s appropriate that that we are actively supportive.

Getting these designations is, of course, no guarantee the therapies will ultimately prove to be successful. But if they are, creating faster pathways means they can get to patients, the people who really need them, at a much faster pace.

 

 

 

 

 

Stem cell agency funds Phase 3 clinical trial for Lou Gehrig’s disease

ALS

At CIRM we don’t have a disease hierarchy list that we use to guide where our funding goes. We don’t rank a disease by how many people suffer from it, if it affects children or adults, or how painful it is. But if we did have that kind of hierarchy you can be sure that Amyotrophic Lateral Sclerosis (ALS), also known as Lou Gehrig’s disease, would be high on that list.

ALS is a truly nasty disease. It attacks the neurons, the cells in our brain and spinal cord that tell our muscles what to do. As those cells are destroyed we lose our ability to walk, to swallow, to talk, and ultimately to breathe.

As Dr. Maria Millan, CIRM’s interim President and CEO, said in a news release, it’s a fast-moving disease:

“ALS is a devastating disease with an average life expectancy of less than five years, and individuals afflicted with this condition suffer an extreme loss in quality of life. CIRM’s mission is to accelerate stem cell treatments to patients with unmet medical needs and, in keeping with this mission, our objective is to find a treatment for patients ravaged by this neurological condition for which there is currently no cure.”

Having given several talks to ALS support groups around the state, I have had the privilege of meeting many people with ALS and their families. I have seen how quickly the disease works and the devastation it brings. I’m always left in awe by the courage and dignity with which people bear it.

BrainStorm

I thought of those people, those families, today, when our governing Board voted to invest $15.9 million in a Phase 3 clinical trial for ALS run by BrainStorm Cell Therapeutics. BrainStorm is using mesenchymal stem cells (MSCs) that are taken from the patient’s own bone marrow. This reduces the risk of the patient’s immune system fighting the therapy.

After being removed, the MSCs are then modified in the laboratory to  boost their production of neurotrophic factors, proteins which are known to help support and protect the cells destroyed by ALS. The therapy, called NurOwn, is then re-infused back into the patient.

In an earlier Phase 2 clinical trial, NurOwn showed that it was safe and well tolerated by patients. It also showed evidence that it can help stop, or even reverse  the progression of the disease over a six month period, compared to a placebo.

CIRM is already funding one clinical trial program focused on treating ALS – that’s the work of Dr. Clive Svendsen and his team at Cedars Sinai, you can read about that here. Being able to add a second project, one that is in a Phase 3 clinical trial – the last stage before, hopefully, getting approval from the Food and Drug Administration (FDA) for wider use – means we are one step closer to being able to offer people with ALS a treatment that can help them.

Diane Winokur, the CIRM Board Patient Advocate member for ALS, says this is something that has been a long time coming:

CIRM Board member and ALS Patient Advocate Diane Winokur

“I lost two sons to ALS.  When my youngest son was diagnosed, he was confident that I would find something to save him.  There was very little research being done for ALS and most of that was very limited in scope.  There was one drug that had been developed.  It was being released for compassionate use and was scheduled to be reviewed by the FDA in the near future.  I was able to get the drug for Douglas.  It didn’t really help him and it was ultimately not approved by the FDA.

When my older son was diagnosed five years later, he too was convinced I would find a therapy.  Again, I talked to everyone in the field, searched every related study, but could find nothing promising.

I am tenacious by nature, and after Hugh’s death, though tempted to give up, I renewed my search.  There were more people, labs, companies looking at neurodegenerative diseases.

These two trials that CIRM is now funding represent breakthrough moments for me and for everyone touched by ALS.  I feel that they are a promising beginning.  I wish it had happened sooner.  In a way, though, they have validated Douglas and Hugh’s faith in me.”

These therapies are not a cure for ALS. At least not yet. But what they will do is hopefully help buy people time, and give them a sense of hope. For a disease that leaves people desperately short of both time and hope, that would be a precious gift. And for people like Diane Winokur, who have fought so hard to find something to help their loved ones, it’s a vindication that those efforts have not been in vain.

One man’s journey with leukemia has turned into a quest to make bone marrow stem cell transplants safer

Dr. Lukas Wartman in his lab in March 2011 (left), before he developed chronic graft-versus-host disease, and last month at a physical therapy session (right). (Photo by Whitney Curtis for Science Magazine)

I read a story yesterday in Science Magazine that really stuck with me. It’s about a man who was diagnosed with leukemia and received a life-saving stem cell transplant that is now threatening his health.

The man is name Lukas Wartman and is a doctor at Washington University School of Medicine in St. Louis. He was first diagnosed with a type of blood cancer called acute lymphoblastic leukemia (ALL) in 2003. Since then he has taken over 70 drugs and undergone two rounds of bone marrow stem cell transplants to fight off his cancer.

The first stem cell transplant was from his brother, which replaced Wartman’s diseased bone marrow, containing blood forming stem cells and immune cells, with healthy cells. In combination with immunosuppressive drugs, the transplant worked without any complications. Unfortunately, a few years later the cancer returned. This time, Wartman opted for a second transplant from an unrelated donor.

While the second transplant and cancer-fighting drugs have succeeded in keeping his cancer at bay, Wartman is now suffering from something equally life threatening – a condition called graft vs host disease (GVHD). In a nut shell, the stem cell transplant that cured him of cancer and saved his life is now attacking his body.

GVHD, a common side effect of bone marrow transplants

GVHD is a disease where donor transplanted immune cells, called T cells, expand and attack the cells and tissues in your body because they see them as foreign invaders. GVHD occurs in approximately 50% of patients who receive bone marrow, peripheral blood or cord blood stem cell transplants, and typically affects the skin, eyes, mouth, liver and intestines.

The main reason why GVHD is common following blood stem cell transplants is because many patients receive transplants from unrelated donors or family members who aren’t close genetic matches. Half of patients who receive these types of transplants develop an acute form of GVHD within 100 days of treatment. These patients are put on immunosuppressive steroid drugs with the hope that the patient’s body will eventually kill off the aggressive donor T cells.

This was the case for Wartman after the first transplant from his brother, but the second transplant from an unrelated donor eventually caused him to develop the chronic form of GVHD. Wartman is now suffering from weakened muscles, dry eyes, mouth sores and skin issues as the transplanted immune cells slowly attack his body from within. Thankfully, his major organs are still untouched by GVHD, but Wartman knows it could be only a matter of time before his condition worsens.

Dr. Lukas Wartman has to use eye drops every 20 minutes to deal with dry eyes caused by GVHD. (Photo by Whitney Curtis for Science Magazine)

Hope for GVHD sufferers

Wartman along with other GVHD patients are basically guinea pigs in a field where effective drugs are still being developed and tested. Many of these patients, including Wartman, have tried many unproven treatments or drugs for other disease conditions in desperate hope that something will work. It’s a situation that is heartbreaking not only for the patient but also for their families and doctors.

There is hope for GVHD patients however. Science Magazine mentioned two promising drugs for GVHD, ibrutinib and ruxolitinib. Both received breakthrough therapy designation from the US Food and Drug Administration and could be the first approved treatments for GVHD.

Another promising therapy is called Prochymal. It’s a stem cell therapy developed by former CIRM President and CEO, Dr. Randy Mills, at Osiris Therapeutics. Prochymal is already approved to treat the acute form of GVHD in Canada, and is currently being tested in phase 3 trials in the US in young children and adults.

While CIRM isn’t currently funding clinical trials for GVHD, we are funding a trial out of Stanford University led by Dr. Judy Shizuru that aims to improve the outcome of bone marrow stem cell transplants in patients. Shizuru says that these transplants are “the most powerful form of cell therapy out there, for cancers or deficiencies in blood formation” but they come with their own set of potentially deadly side effects such as GVHD.

Shizuru is testing an antibody drug that blocks a signaling protein called CD117, which sits on the surface of blood stem cells and acts as an elimination signal. By turning off this protein, her team improved the engraftment of bone marrow stem cells in mice that had leukemia and removed their need for chemotherapy treatment. The therapy is in a Phase 1 trial for patients with an immune disease called severe combined immunodeficiency (SCID) who receive bone marrow transplants, but Shizuru said that her hope is the drug could also treat patients with certain cancers or blood diseases.

Advocating for better GVHD treatments

The reason the article in Science Magazine spoke to me is because of the power of Wartman’s story. Wartman’s battle with ALL and now GVHD has transformed him into one of the strongest patient voices advocating for the development of new GVHD treatments. Jon Cohen, the author of the Science Magazine article, explained:

“The urgency of his case has turned Wartman into one of the world’s few patients who advocate for GVHD research, prevention, and treatment. ‘Most people it affects suffer quietly,” says Wartman. ‘They’re grateful they’re alive, and they’re beaten down. It’s the paradox of being cured and dying of the cure. Even if you can get past that, you don’t have the energy to advocate, and that’s really tragic.’”

Patients like Wartman are an inspiration not only to other people with GVHD, but also to funding agencies and scientists working to advance GVHD research towards a cure. We don’t want these patients to suffer quietly. Wartman’s story is an important reminder that there’s a lot more work to do to make bone marrow transplants safer – so that they save lives without later putting those lives at risk.