You know you are working with some of the finest scientific minds in the world when they get elected to the prestigious National Academy of Sciences (NAS). It’s the science equivalent of the baseball, football or even Rock and Roll Hall of Fame. People only get in if their peers vote them in. It’s considered one of the highest honors in science, one earned over many decades of hard work. And when it comes to hard work there are few people who work harder than U.C. San Diego’s Dr. Lawrence Goldstein, one of the newly elected members of the NAS.
For more than 25 years Larry’s work has targeted the brain and, in particular, Alzheimer’s disease and amyotrophic lateral sclerosis (ALS) better known as Lou Gehrig’s disease.
In 2012 his team was the first to create stem cell models for two different forms of Alzheimer’s, the hereditary and the sporadic forms. This gave researchers a new way of studying the disease, helping them better understand what causes it and looking at new ways of treating it.
His work has also helped develop a deeper understanding of the genetics of Alzheimer’s and to identify possible new targets for stem cell and other therapies.
Larry was typically modest when he heard the news, saying: “I have been very fortunate to have wonderful graduate students and fellows who have accomplished a great deal of excellent research. It is a great honor for me and for all of my past students and fellows – I am obviously delighted and hope to contribute to the important work of the National Academy of Sciences.”
But Larry doesn’t intend to rest on his laurels. He says he still has a lot of work to do, including “raising funding to test a new drug approach for Alzheimer’s disease that we’ve developed with CIRM support.”
Jennifer Briggs Braswell, PhD, worked with Larry at UCSD from 2005 to 2018. She says Larry’s election to the NAS is well deserved:
“His high quality publications, the pertinence of his studies in neurodegeneration to our current problems, and his constant, unwavering devotion to the next generation of scientists is matched only by his dedication to improving public understanding of science to motivate social, political, and financial support.
“He has been for me a supportive mentor, expressing enthusiastic belief in the likely success of my good ideas and delivering critique with kindness and sympathy. He continues to inspire me, our colleagues at UCSD and other communities, advocate publicly for the importance of science, and work tirelessly on solutions for neurodegenerative disorders.”
On March 19th we held a special Facebook Live “Ask the Stem Cell Team About Autism” event. We were fortunate enough to have two great experts – Dr. Alysson Muotri from UC San Diego, and CIRM’s own Dr. Kelly Shepard. As always there is a lot of ground to cover in under one hour and there are inevitably questions we didn’t get a chance to respond to. So, Dr. Shepard has kindly agreed to provide answers to all the key questions we got on the day.
If you didn’t get a chance to see the event you can watch the video here. And feel free to share the link, and this blog, with anyone you think might be interested in the material.
Can umbilical cord blood stem cells help reduce some of the symptoms?
This question was addressed by Dr. Muotri in the live presentation. To recap, a couple of clinical studies have been reported from scientists at Duke University and Sutter Health, but the results are not universally viewed as conclusive. The Duke study, which focused on very young children, reported some improvements in behavior for some of the children after treatment, but it is important to note that this trial had no placebo control, so it is not clear that those patients would not have improved on their own. The Duke team has moved forward with larger trial and placebo control.
Does it have to be the child’s own cord blood or could donated blood work too?
In theory, a donated cord product could be used for similar purposes as a child’s own cord, but there is a caveat- the donated cord tissues must have some level of immune matching with the host in order to not be rejected or lead to other complications, which under certain circumstances, could be serious.
Some clinics claim that the use of fetal stem cells can help stimulate improved blood and oxygen flow to the brain. Could that help children with autism?
Fetal stem cells have been tested in FDA approved/sanctioned clinical trials for certain brain conditions such as stroke and Parkinson Disease, where there is clearer understanding of how and which parts of the brains are affected, which nerve cells have been lost or damaged, and where there is a compelling biological rationale for how certain properties the transplanted cells, such as their anti-inflammatory properties, could provide benefit.
In his presentation, Dr. Muotri noted that neurons are not lost in autistic brains, so there is nothing that would be “replaced” by such a treatment. And although some forms of autism might include inflammation that could potentially be mitigated, it is unlikely that the degree of benefit that might come from reducing inflammation would be worth the risks of the treatment, which includes intracranial injection of donated material. Unfortunately, we still do not know enough about the specific causes and features of autism to determine if and to what extent stem cell treatments could prove helpful. But we are learning more every day, especially with some of the new technologies and discoveries that have been enabled by stem cell technology.
Some therapies even use tissue from sheep claiming that a pill containing sheep pancreas can migrate to and cure a human pancreas, pills containing sheep brains can help heal human brains. What are your thoughts on those?
For some conditions, there may be a scientific rationale for how a specific drug or treatment could be delivered orally, but this really depends on the underlying biology of the condition, the means by which the drug exerts its effect, and how quickly that drug or substance will be digested, metabolized, or cleared from the body’s circulation. Many drugs that are delivered orally do not reach the brain because of the blood-brain barrier, which serves to isolate and protect the brain from potentially harmful substances in the blood circulation. For such a drug to be effective, it would have to be stable within the body for a period of time, and be something that could exert its effects on the brain either directly or indirectly.
Sheep brain or pancreas (or any other animal tissue consumed) in a pill form would be broken down into basic components immediately by digestion, i.e. amino acids, sugars, much like any other meat or food. Often complex treatments designed to be specifically targeted to the brain are delivered by intra-cranial/intrathecal injection, or by developing special strategies to evade the blood brain barrier, a challenge that is easier said than done. For autism, there is still a lot to be learned regarding how a therapeutic intervention might work to help people, so for now, I would caution against the use of dietary supplements or pills that are not prescribed or recommended by your doctor.
What are the questions parents should ask before signing up for any stem cell therapy
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
A CIRM-funded trial conducted by Oncternal Therapeutics in collaboration with UC San Diego released an interim clinical data update for patients with mantle cell lymphoma (MCL), a type of blood cancer.
The treatment being developed involves an antibody called cirmtuzumab (named after yours truly) being used with a cancer fighting drug called ibrutinib. The antibody recognizes and attaches to a protein on the surface of cancer stem cells. This attachment disables the protein, which slows the growth of the blood cancer and makes it more vulnerable to anti-cancer drugs.
Here are the highlights from the new interim clinical data:
Patients had received a median of two prior therapies before participating in this study including chemotherapy; autologous stem cell transplant (SCT); autologous SCT and CAR-T therapy; autologous SCT and allogeneic SCT; and ibrutinib with rituximab, a different type of antibody therapy.
6 of the 12 patients in the trial experienced a Complete Response (CR), which is defined as the disappearance of all signs of cancer in response to treatment.
All six CRs are ongoing, including one patient who has remained in CR for more than 21 months past treatment.
Four of the six patients achieved CRs within four months on the combination of cirmtuzumab and ibrutinib.
Of the remaining 6 patients, 4 experienced a Partial Response (PR), which is defined as a decrease in the extent of the cancer in the body.
The remaining two patients experienced Stable Disease (SD), which is defined as neither an increase or decrease in the extent of the cancer.
The full interim clinical data update can be viewed in the press release here.
Do an online search for “autism stem cells” and you quickly come up with numerous websites offering stem cell therapies for autism. They offer encouraging phrases like “new and effective approach” and “a real, lasting treatment.” They even include dense scientific videos featuring people like Dr. Arnold Caplan, a professor at Case Western Reserve University who is known as the “father of the mesenchymal stem” (it would be interesting to know if Dr. Caplan knows he is being used as a marketing tool?)
The problem with these sites is that they are offering “therapies” that have never been proven to be safe, let alone effective. They are also very expensive and are not covered by insurance. Essentially they are preying on hope, the hope that any parent of a child with autism spectrum disorder (ASD) will do anything and everything they can to help their child.
But there is encouraging news about stem cells and autism, about their genuine potential to help children with ASD. That’s why we are holding a special Facebook Live “Ask the Stem Cell Team” about Autism on Thursday, March 19th at noon (PDT).
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 Shephard.
We’ll take a look at Dr. Muotri’s work and also discuss the work of other researchers in the field, such as Dr. Joanne Kurtzberg’s work at Duke University.
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 email@example.com.
CIRM funds a lot of research and all of it has life-saving potential. But every once in a while you come across a story about someone benefiting from CIRM-supported research that highlights why the work we do is so important. This story is about a brilliant researcher at UC San Diego developing a treatment for a really rare disease, one that was unlikely to get funding from a big pharmaceutical company because it offered little chance for a return on its investment. At CIRM we don’t have to worry about things like that. Stories like this are our return on investment.
Our thanks to our colleagues at UCSD News for allowing us to run this piece in full.
By Heather Buschman, PhD
Born with a rare disease called cystinosis, 20-year-old Jordan Janz arrived at a crossroads: continue life as-is, toward a future most likely leading to kidney failure and an early death or become the first patient in the world to undergo a new gene-and-stem cell therapy developed over more than a decade by UC San Diego School of Medicine researchers
For the majority of Jordan Janz’s 20 years of life, most neighbors in his tiny Canadian town never knew he was sick. Janz snowboarded, hunted and fished. He hung with friends, often playing ice hockey video games. He worked in shipping and receiving for a company that makes oil pumps.
But there were times when Janz was younger that he vomited up to 13 times each day. He received a growth hormone injection every day for six years. He needed to swallow 56 pills every day just to manage his symptoms. And the medication required around-the-clock administration, which meant his mother or another family member had to get up with him every night.
“I was tired for school every day,” Janz said. “I was held back in second grade because I missed so much school. And because the medication had a bad odor to it, when I did go to school kids would ask, ‘What’s that smell?’ It was hard.”
Janz was born with cystinosis, a rare metabolic disorder that’s detected in approximately one in 100,000 live births worldwide. People with cystinosis inherit a mutation in the gene that encodes a protein called cystinosin. Cystinosin normally helps cells transport the amino acid cystine. Because cells in people with cystinosis don’t produce the cystinosin protein, cystine accumulates. Over the years, cystine crystals build up and begin to damage tissues and organs, from the kidneys and liver to muscles, eyes and brain. Numerous symptoms and adverse consequences result.
These days, Janz manages his condition. There’s a time-release version of the symptom-relieving medication now that allows him to go 12 hours between doses, allowing for a good night’s sleep. But there’s no stopping the relentless accumulation of cystine crystals, no cure for cystinosis.
In October 2019, Janz became the first patient to receive treatment as part of a Phase I/II clinical trial to test the safety and efficacy of a unique gene therapy approach to treating cystinosis. The treatment was developed over more than a decade of research by Stephanie Cherqui, PhD, associate professor of pediatrics, and her team at University of California San Diego School of Medicine.
“The day they started looking for people for the trial, my mom picked up the phone, found a number for Dr. Cherqui, called her and put my name in as a candidate,” Janz said.
Janz’s mom, Barb Kulyk, has long followed Cherqui’s work. Like many parents of children with cystinosis, Kulyk has attended conferences, read up on research and met many other families, doctors and scientists working on the condition. Kulyk says she trusts Cherqui completely. But she was understandably nervous for her son to be the first person ever to undergo a completely new therapy.
“It’s like giving birth,” she said shortly before Janz received his gene therapy. “You’re really looking forward to the outcome, but dreading the process.”
Cherqui’s gene therapy approach involves genetical modifying the patient’s own stem cells. To do this, her team obtained hematopoietic stem cells from Janz’s bone marrow. These stem cells are the precursors to all blood cells, including both red blood cells and immune cells. The scientists then re-engineered Janz’s stem cells in a lab using gene therapy techniques to introduce a normal version of the cystinosin gene. Lastly, they reinfused Janz with his own now-cystinosin-producing cells. The approach is akin to a bone marrow transplant — the patient is both donor and recipient.
“A bone marrow transplant can be very risky, especially when you take hematopoietic stem cells from a another person. In that case, there’s always the chance the donor’s immune cells will attack the recipient’s organs, so-called graft-versus-host disease,” Cherqui explained. “It’s a great advantage to use the patient’s own stem cells.”
As is the case for other bone marrow transplants, Janz’s gene-modified stem cells are expected to embed themselves in his bone marrow, where they should divide and differentiate to all types of blood cells. Those cells are then expected to circulate throughout his body and embed in his tissues and organs, where they should produce the normal cystinosin protein. Based on Cherqui’s preclinical data, she expects the cystinosin protein will be transferred to the surrounding diseased cells. At that point, Janz’s cells should finally be able to appropriately transport cystine for disposal — potentially alleviating his symptoms.
Before receiving his modified stem cells, Janz had to undergo chemotherapy to make space in his bone marrow for the new cells. Not unexpectedly, Janz experienced a handful of temporary chemotherapy-associated side-effects, including immune suppression, hair loss and fatigue. He also had mucositis, an inflammation of mucous membranes lining the digestive tract, which meant he couldn’t talk or eat much for a few days.
Now, only three months after his transfusion of engineered stem cells, Cherqui reports that Janz is making a good recovery, though it’s still too early to see a decrease in his cystinosis-related symptoms.
“I’ve been sleeping at least 10 hours a day for the last few weeks,” Janz said. “It’s crazy, but I know my body is just working hard to, I guess, create a new ‘me.’ So it’s no wonder I’m tired. But I’m feeling okay overall.
“One of the hardest parts for me is being inactive for so long. I’m not used to doing nothing all day. But I’m taking an online course while I wait for my immune system to rebuild. And I’m getting pretty good at video games.”
Like all Phase I/II clinical trials, the current study is designed to first test the safety and tolerability of the new treatment. Janz knows the treatment might not necessarily help him.
“When we started this trial, my mom explained it like this: ‘We have a tornado at the front door and a tsunami at the back door, and we have to pick one to go through. Neither will be any fun and we don’t know what’s going to happen, but you have to believe you will make it and go.
“So we weighed the pros and cons and, basically, if I don’t do this trial now, when I’m older I might not be healthy and strong enough for it. So I decided to go for it because, even if there are consequences from the chemotherapy, if it works I could live 20 years longer than I’m supposed to and be healthy for the rest of my life. That’s worth it.”
Besides the possible benefit to himself, Janz also sees his participation in the clinical trial as a way to contribute to the tight-knit community of families with children who have cystinosis.
“I’m willing to do if it helps the kids,” he said. “Somebody has to do it. I don’t have the money to donate to scientific conferences and stuff like that, but I can do this trial.”
If the treatment continues to meet certain criteria for safety and efficacy for Janz and one other participant after three months, two more adult participants will be enrolled. Three months after that, if the treatment continues to be safe and effective, the trial might enroll two adolescent participants. To participate in the clinical trial, individuals must meet specific eligibility requirements.
Later in the trial, Cherqui and team will begin measuring how well the treatment actually works. The specific objectives include assessing the degree to which gene-modified stem cells establish themselves in bone marrow, how they affect cystine levels and cystine crystal counts in blood and tissues.
“This trial is the first to use gene-modified hematopoietic stem cell gene therapy to treat a multi-organ degenerative disorder for which the protein is anchored in the membrane of the lysosomes, as opposed to secreted enzymes,” Cherqui said. “We were amazed when we tested this approach in the mouse model of cystinosis — autologous stem cell transplantation reversed the disease. The tissues remained healthy, even the kidneys and the eyes.”
Trial participants are closely monitored for the first 100 days after treatment, then tested again at six, nine, 12, 18 and 24 months post-gene therapy for a variety of factors, including vital signs, cystine levels in a number of organs, kidney function, hormone function and physical well-being.
“If successful in clinical trials, this approach could provide a one-time, lifelong therapy that may prevent the need for kidney transplantation and long-term complications caused by cystine buildup,” Cherqui said.
For the trial participants, all of the pre-treatment tests, the treatment itself, and monitoring afterward means a lot of travel to and long stays in San Diego.
It’s tough on Kulyk and Janz. They have to fly in from Alberta, Canada and stay in a San Diego hotel for weeks at a time. Kulyk has two older adult children, as well as a 12-year-old and a seven-year-old at home.
“I’ve missed a lot of things with my other kids, but none of them seem to hold any grudges,” she said. “They seem to be totally fine and accepting. They’re like, ‘We’re fine, mom. You go and take care of Jordan.’”
Janz is looking forward to getting back home to his friends, his dog and his job, which provided him with paid leave while he received treatment and recovers.
For Cherqui, the search for a cystinosis cure is more than just a scientific exercise. Cherqui began working on cystinosis as a graduate student more than 20 years ago. At the time, she said, it was simply a model in which to study genetics and gene therapy.
“When you read about cystinosis, it’s just words. You don’t put a face to it. But after I met all the families, met the kids, and now that I’ve seen many of them grow up, and some of them die of the disease — now it’s a personal fight, and they are my family too.”
Patients with cystinosis typically experience kidney failure in their 20s, requiring kidney dialysis or transplantation for survival. For those born with cystinosis who make it into adulthood, the average lifespan is approximately 28 years old.
“I’m optimistic about this trial because it’s something we’ve worked so hard for and now it’s actually happening, and these families have so much hope for a better treatment,” Cherqui said. “After all the years of painstaking laboratory research, we now need to move into the clinic. If this works, it will be wonderful. If it doesn’t, we will all be disappointed but a least we’ll be able to say we tried.”
Nancy Stack, who founded the Cystinosis Research Foundation after her own daughter, Natalie, was diagnosed with the disease, calls Cherqui “the rock star of our community.”
“She cares deeply about the patients and is always available to talk, to explain her work and to give us hope,” Stack said. “She said years ago that she would never give up until she found the cure — and now we are closer to a cure than ever before.” (Read more about Natalie here.)
In addition to cystinosis, Cherqui says this type of gene therapy approach could also lead to treatment advancements for other multi-organ degenerative disorders, such as Friedreich’s ataxia and Danon disease, as well as other kidney, genetic and systemic diseases similar to cystinosis.
While they wait for the long-term results of the treatment, Kulyk is cautiously hopeful.
“Moms are used to being able to fix everything for their children — kiss boo-boos make them better, make cupcakes for school, whip up Halloween costumes out of scraps, pull a coveted toy out of thin air when it has been sold out for months.
“But we have not been able to fix this, to take it away. I not only want this disease gone for my child, I want cystinosis to be nothing more than a memory for all the children and adults living with it. I know that even if and when Jordan is cured, there will still be so much work to do, in terms of regulatory approvals and insurance coverage.
“Having hope for your child’s disease to be cured is a slippery slope. We have all been there, held hope in our hands and had to let go. But, I find myself in a familiar place, holding onto hope again and this time I am not letting go.”
For more information about the Phase I/II clinical trial for cystinosis and to learn how to enroll, call 1-844-317-7836 or email firstname.lastname@example.org.
Cherqui’s research has been funded by the Cystinosis Research Foundation, California Institute for Regenerative Medicine (CIRM), and National Institutes of Health. She receives additional support from the Sanford Stem Cell Clinical Center and CIRM-funded Alpha Stem Cell Clinic at UC San Diego Health, and AVROBIO.
Cystic fibrosis is a disorder that mostly affects the lungs. It is caused by a mutation in a gene called cystic fibrosis transmembrane conductance regulator (CFTR). As a result of this mutation, cells that produce mucus (a slimy substance like the one in your nose) secrete a thicker-than-normal mucus that can create blockages in the lungs and digestive system. In the lungs, this thicker mucus is a perfect breeding ground for bacteria, leading to more chronic lung infections in those with cystic fibrosis.
However, some people with cystic fibrosis don’t develop lung infections as early or as often as others with the disorder. Thanks to a CIRM funded study, Dr. Kelly Frazer and her team at the UC San Diego School of Medicine have discovered why this might happen.
Before we get into that, we need to dive a bit deeper into cystic fibrosis and what causes this thicker-than normal mucus. In healthy people, CFTR is embedded in the membrane of most cells, where it forms a channel that allows chloride – a component of salt – to travel through. This flow ensures that cells have the right balance of salt and water. In people with cystic fibrosis, the CFTR mutation means that the channel doesn’t work as well, the flow of water is blocked resulting in more thick and sticky mucus. There are medications that can help boost CFTR, but they are very expensive and don’t work for everyone.
Dr. Frazer and her team discovered that a gene, called RNF5, also prevents CFTR from functioning well. People with cystic fibrosis who have lower levels of RNF5 have channels that function better, with less mucus build up, compared to people with higher levels of RNF5. This could potentially explain why some with cystic fibrosis get more chronic lung infections compared to others with the condition.
In a press release by UC San Diego School of Medicine, Dr. Frazer talks about how RNF5 could play a role in treating patients.
“The cystic fibrosis field is trying to figure out what are the modifiers across the genome that increase or decrease the probability that an individual patient will respond to these expensive drugs. RNF5 may be one of these modifier genes.”
In the same press release, Dr. Matteo D’Antonio, a project scientist in Dr. Frazer’s lab, talks about how these findings could result in more personalized treatments for people with cystic fibrosis.
“This study uncovered a new aspect of cystic fibrosis — one that could lead to new drug design and development, and allow clinicians to better tailor treatments.”
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.
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.”
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.”
For several years, researchers have been able to take stem cells and use them to make three dimensional structures called organoids. These are a kind of mini organ that scientists can then use to study what happens in the real thing. For example, creating kidney organoids to see how kidney disease develops in patients.
Scientists can do the same with brain cells, creating clumps
of cells that become a kind of miniature version of parts of the brain. These
organoids can’t do any of the complex things our brains do – such as thinking –
but they do serve as useful physical models for us to use in trying to develop
a deeper understanding of the brain.
Now Alysson Muotri and his team at UC San Diego – in
a study supported by two
grants from CIRM – have taken the science one step further, developing
brain organoids that allow us to measure the level of electrical activity they
generate, and then compare it to the electrical activity seen in the developing
brain of a fetus. That last sentence might cause some people to say “What?”, but
this is actually really cool science that could help us gain a deeper
understanding of how brains develop and come up with new ways to treat problems
in the brain caused by faulty circuitry, such as autism or schizophrenia.
The team developed new, more effective methods of growing
clusters of the different kinds of cells found in the brain. They then placed
them on a multi-electrode array, a kind of muffin tray that could measure
electrical impulses. As they fed the cells and increased the number of cells in
the trays they were able to measure changes in the electrical impulses they
gave off. The cells went from producing 3,000 spikes a minute to 300,000 spikes
a minute. This is the first time this level of activity has been achieved in a
cell-based laboratory model. But that’s not all.
When they further analyzed the activity of the organoids, they found there were some similarities to the activity seen in the brains of premature babies. For instance, both produced short bursts of activity, followed by a period of inactivity.
In a news
release Muotri says they were surprised by the finding:
“We couldn’t believe it at first — we
thought our electrodes were malfunctioning. Because the data were so striking,
I think many people were kind of skeptical about it, and understandably so.”
Muotri knows that this research –
published in the journal Cell Stem Cell – raises ethical issues and he is
quick to say that these organoids are nothing like a baby’s brain, that they differ
in several critical ways. The organoids are tiny, not just in size but also in
the numbers of cells involved. They also don’t have blood vessels to keep them
alive or help them grow and they don’t have any ability to think.
“They are far from being functionally
equivalent to a full cortex, even in a baby. In fact, we don’t yet have a way
to even measure consciousness or sentience.”
What these organoids do have is the ability to help us look
at the structure and activity of the brain in ways we never could before. In
the past researchers depended on mice or other animals to test new ideas or
therapies for human diseases or disorders. Because our brains are so different
than animal brains those approaches have had limited results. Just think about
how many treatments for Alzheimer’s looked promising in animal models but
failed completely in people.
These new organoids allow us to explore how new therapies
might work in the human brain, and hopefully increase our ability to develop
more effective treatments for conditions as varied as epilepsy and autism.
In addition to approving funding for breast cancer related brain metastases last week, the CIRM Board also approved an additional $19.7 million geared towards our translational research program. The goal of this program is to help promising projects complete the testing needed to begin talking to the US Food and Drug Administration (FDA) about holding a clinical trial.
Before getting into the details of each project, here is a table with a brief synopsis of the awards:
TRAN1 – 11532
$3.73 million was awarded to Dr. Mark Humayun at USC to develop a novel therapeutic product capable of slowing the progression of age-related macular degeneration (AMD).
AMD is an eye disease that causes severe vision impairment, resulting in the inability to read, drive, recognize faces, and blindness if left untreated. It is the leading cause of vision loss in the U.S. and currently affects over 2 million Americans. By the year 2050, it is projected that the number of affected individuals will more than double to over 5 million. A layer of cells in the back of the eye called the retinal pigment epithelium (RPE) provide support to photoreceptors (PRs), specialized cells that play an important role in our ability to process images. The dysfunction and/or loss of RPE cells plays a critical role in the loss of PRs and hence the vision problems observed in AMD. One form of AMD is known as dry AMD (dAMD) and accounts for about 90% of all AMD cases.
The approach that Dr. Humayun is developing will use a biologic product produced by human embryonic stem cells (hESCs). This material will be injected into the eye of patients with early development of dAMD, supporting the survival of photoreceptors in the affected retina.
TRAN1 – 11579
$6.23 million was awarded to Dr. Mark Tuszynski at UCSD to develop a neural stem cell therapy for spinal cord injury (SCI).
According to data from the National Spinal
Cord Injury Statistical Center, as of 2018, SCI affects an estimated 288,000
people in the United States alone, with about 17,700 new cases each year. There
are currently no effective therapies for SCI. Many people suffer SCI in early
adulthood, leading to life-long disability and suffering, extensive treatment
needs and extremely high lifetime costs of health care.
The approach that Dr. Tuszynski is developing will use hESCs to create neural stem cells (NSCs). These newly created NSCs would then be grafted at the site of injury of those with SCI. In preclinical studies, the NSCs have been shown to support the formation of neuronal relays at the site of SCI. The neuronal relays allow the sensory neurons in the brain to communicate with the motor neurons in the spinal cord to re-establish muscle control and movement.
TRAN1 – 11548
$4.83 million was awarded to Dr. Brian Cummings at UC Irvine to develop a neural stem cell therapy for traumatic brain injury (TBI).
TBI is caused by a bump, blow, or jolt to the head that disrupts the normal function of the brain, resulting in emotional, mental, movement, and memory problems. There are 1.7 million people in the United States experiencing a TBI that leads to hospitalization each year. Since there are no effective treatments, TBI is one of the most critical unmet medical needs based on the total number of those affected and on a cost basis.
The approach that Dr. Cummings is developing will also use hESCs to create NSCs. These newly created NSCs would be integrated with injured tissue in patients and have the ability to turn into the three main cell types in the brain; neurons, astrocytes, and oligodendrocytes. This would allow for TBI patients to potentially see improvements in issues related to memory, movement, and anxiety, increasing independence and lessening patient care needs.
TRAN1 – 11628
$4.96 million was awarded to Dr. Evan Snyder at Sanford Burnham Prebys to develop a neural stem cell therapy for perinatal hypoxic-ischemic brain injury (HII).
HII occurs when there is a lack of oxygen flow to the brain. A newborn infant’s body can compensate for brief periods of depleted oxygen, but if this lasts too long, brain tissue is destroyed, which can cause many issues such as developmental delay and motor impairment. Current treatment for this condition is whole-body hypothermia (HT), which consists of significantly reducing body temperature to interrupt brain injury. However, this is not very effective in severe cases of HII.
The approach that Dr. Snyder is developing will use an established neural stem cell (NSC) line. These NSCs would be injected and potentially used alongside HT treatment to increase protection from brain injury.