Senior author of the study Clive Svendsen, PhD (center)
With funding support from the California Institute for Regenerative Medicine (CIRM), Cedars-Sinai investigators have developed an investigational therapy using support cells and a protective protein that can be delivered past the blood-brain barrier. This combined stem cell and gene therapy can potentially protect diseased motor neurons in the spinal cord of patients with amyotrophic lateral sclerosis, a fatal neurological disorder known as ALS or Lou Gehrig’s disease.
In the first trial of its kind, the Cedars-Sinai team showed that delivery of this combined treatment is safe in humans. The findings were reported in the peer-reviewed journal Nature Medicine.
What causes ALS?
ALS is a progressive neurodegenerative disease that affects nerve cells in the brain and spinal cord. About 6,000 people are diagnosed with ALS each year in the U.S., and the average survival time is two to five years.
The disease results when the cells in the brain or spinal cord that instruct muscles to move—called motor neurons—die off. People with the disease lose the ability to move their muscles and, over time, the muscles atrophy and people become paralyzed and eventually die. There is no effective therapy for the disease.
Using Stem Cells to Treat ALS
In a news release, senior author Clive Svendsen, PhD, executive director of the Cedars-Sinai Board of Governors Regenerative Medicine Institute, says using stem cells shows lots of promise in treating patients with ALS.
“We were able to show that the engineered stem cell product can be safely transplanted in the human spinal cord. And after a one-time treatment, these cells can survive and produce an important protein for over three years that is known to protect motor neurons that die in ALS,” Svendsen says.
Aimed at preserving leg function in patients with ALS, the engineered cells could pave the way to a therapeutic option for this disease that causes progressive muscle paralysis, robbing people of their ability to move, speak and breathe.
The study used stem cells originally designed in Svendsen’s laboratory to produce a protein called glial cell line-derived neurotrophic factor (GDNF). This protein can promote the survival of motor neurons, which are the cells that pass signals from the brain or spinal cord to a muscle to enable movement.
In patients with ALS, diseased glial cells can become less supportive of motor neurons, and these motor neurons progressively degenerate, causing paralysis.
By transplanting the engineered protein-producing stem cells in the central nervous system, where the compromised motor neurons are located, these stem cells can turn into new supportive glial cells and release the protective protein GDNF, which together helps the motor neurons stay alive.
Ensuring Safety in the Trial
The primary goal of the trial was to ensure that delivering the cells releasing GDNF to the spinal cord did not have any safety issues or negative effects on leg function.
In this trial, none of the 18 patients treated with the therapy—developed by Cedars-Sinai scientists and funded by CIRM—had serious side effects after the transplantation, according to the data.
Because patients with ALS usually lose strength in both legs at a similar rate, investigators transplanted the stem cell-gene product into only one side of the spinal cord so that the therapeutic effect on the treated leg could be directly compared to the untreated leg.
After the transplantation, patients were followed for a year so the team could measure the strength in the treated and untreated legs. The goal of the trial was to test for safety, which was confirmed, as there was no negative effect of the cell transplant on muscle strength in the treated leg compared to the untreated leg.
What’s Next?
Investigators expect to start a new study with more patients soon. They will be targeting lower in the spinal cord and enrolling patients at an earlier stage of the disease to increase the chances of seeing effects of the cells on the progression of ALS.
“We are very grateful to all the participants in the study,” said Svendsen. “ALS is a very tough disease to treat, and this research gives us hope that we are getting closer to finding ways to slow down this disease.”
The Cedars-Sinai team is also using the GDNF-secreting stem cells in another CIRM-funded clinical trial for ALS, transplanting the cells into a specific brain region, called the motor cortex that controls the initiation of movement in the hand. The clinical trial is also funded by CIRM.
The California Institute for Regenerative Medicine (CIRM) remains committed to funding research and clinical trials to treat ALS. To date, CIRM has provided $93 million in funding for research to treat ALS.
Read the original source release of the study here.
One of the great pleasures of my job is getting to meet the high school students who take part in our SPARK or Summer Internship to Accelerate Regenerative Medicine Knowledge program. It’s a summer internship for high school students where they get to spend a couple of months working in a world class stem cell and gene therapy research facility. The students, many of whom go into the program knowing very little about stem cells, blossom and produce work that is quite extraordinary.
One such student is Tan Ieng Huang, who came to the US from China for high school. During her internship at U.C. San Francisco she got to work in the lab of Dr. Arnold Kriegstein. He is the Founding Director of the Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research at the University of California, San Francisco. Not only did she work in his lab, she took the time to do an interview with him about his work and his thoughts on the field.
It’s a fascinating interview and shows the creativity of our SPARK students. You will be seeing many other examples of that creativity in the coming weeks. But for now, enjoy the interview with someone who is a huge presence in the field today, by someone who may well be a huge presence in the not too distant future.
‘a tête-à-tête with Prof. Arnold Kriegstein’
The Kriegstein lab team: Photo courtesy UCSF
Prof. Arnold Kriegstein is the Founding Director of the Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research at the University of California, San Francisco. Prof. Kriegstein is also the Co-Founder and Scientific Advisor of Neurona Therapeutics which seeks to provide effective and safe cell therapies for chronic brain disorder. A Clinician by training, Prof. Kriegstein has been fascinated by the intricate workings of the human brain. His laboratory focuses on understanding the transcriptional and signaling networks active during brain development, the diversity of neuronal cell types, and their fate potential. For a long time, he has been interested in harnessing this potential for translational and therapeutic intervention.
During my SEP internship I had the opportunity to work in the Kriegstein lab. I was in complete awe. I am fascinated by the brain. During the course of two months, I interacted with Prof. Kriegstein regularly, in lab meetings and found his ideas deeply insightful. Here’s presenting some excerpts from some of our discussions, so that it reaches many more people seeking inspiration!
Tan Ieng Huang (TH): Can you share a little bit about your career journey as a scientist?
Prof. Arnold Kriegstein (AK): I wanted to be a doctor when I was very young, but in high school I started having some hands-on research experience. I just loved working in the lab. From then on, I was thinking of combining those interests and an MD/PhD turned out to be an ideal course for me. That was how I started, and then I became interested in the nervous system. Also, when I was in high school, I spent some time one summer at Rockefeller University working on a project that involved operant conditioning in rodents and I was fascinated by behavior and the role of the brain in learning and memory. That happened early on, and turned into an interest in cortical development and with time, that became my career.
TH: What was your inspiration growing up, what made you take up medicine as a career?
AK: That is a little hard to say, I have an identical twin brother. He and I used to always share activities, do things together. And early on we actually became eagle scouts, sort of a boy scout activity in a way. In order to become an eagle scout without having to go through prior steps, we applied to a special program that the scouts had, which allowed us to shadow physicians in a local hospital. I remember doing that at a very young age. It was a bit ironic, because one of the evenings, they showed us films of eye surgery, and my brother actually fainted when they made an incision in the eye. The reason it makes me laugh now is because my brother became an eye surgeon many years later. But I remember our early experience, we both became very fascinated by medicine and medical research.
Tan Ieng and Dr. Arnold Kriegstein at UCSF
TH: What inspired you to start the Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research Institute?
AK: My interest in brain development over the years became focused on earlier stages of development and eventually Neurogenesis, you know, how neurons are actually generated during early stages of in utero brain development. In the course of doing that we discovered that the radial glial cells, which have been thought for decades to simply guide neurons as they migrate, turned out to actually be the neural stem cells, they were making the neurons and also guiding them toward the cortex. So, they were really these master cells that had huge importance and are now referred to as neural stem cells. But at that time, it was really before the stem cell field took off. But because we studied neurogenesis, because I made some contributions to understanding how the brain develops from those precursors or progenitor cells, when the field of stem cells developed, it was very simple for me to identify as someone who studied neural stem cells. I became a neural stem cell scientist. I started a neural stem cell program at Columbia University when I was a Professor there and raised 15 million dollars to seed the program and hired new scientists. It was shortly after that I was approached to join UCSF as the founder of a new stem cell program. And it was much broader than the nervous system; it was a program that covered all the different tissues and organ systems.
TH: Can you tell us a little bit about how stem cell research is contributing to the treatment of diseases? How far along are we in terms of treatments?
AK: It’s taken decades, but things are really starting to reach the clinic now. The original work was basic discovery done in research laboratories, now things are moving towards the clinic. It’s a really very exciting time. Initially the promise of stem cell science was called Regenerative medicine, the idea of replacing injured or worn-out tissues or structures with new cells and new tissues, new organs, the form of regeneration was made possible by understanding that there are stem cells that can be tweaked to actually help make new cells and tissues. Very exciting process, but in fact the main progress so far hasn’t been replacing worn out tissues and injured cells, but rather understanding diseases using human based model of disease. That’s largely because of the advent of induced pluripotent stem cells, a way of using stem cells to make neurons or heart cells or liver cells in the laboratory, and study them both in normal conditions during development and in disease states. Those platforms which are relatively easy to make now and are pretty common all over the world allow us to study human cells rather than animal cells, and the hope is that by doing that we will be able to produce conventional drugs and treatments that work much better than ones we had in the past, because they will be tested in actual human cells rather than animal cells.
TH: That is a great progress and we have started using human models because even though there are similarities with animal models, there are still many species-specific differences, right?
AK: Absolutely, in fact, one of the big problems now in Big Pharma, you know the drug companies, is that they invest millions and sometimes hundreds of millions of dollars in research programs that are based on successes in treating mice, but patients don’t respond the same way. So the hope is that by starting with a treatment that works on human cells it might be more likely that the treatment will work on human patients.
TH: What are your thoughts on the current challenges and future of stem cell research?
AK: I think this is an absolute revolution in modern medicine, the advent of two things that are happening right now, first the use of induced pluripotent stem cells, the ability to make pluripotent cells from adult tissue or cells from an individual allows us to use models of diseases that I mentioned earlier from actual patients. That’s one major advance. And the other is gene editing, and the combination of gene editing and cell-based discovery science allows us to think of engineering cells in ways that can make them much more effective as a form of cell therapy and those cell therapies have enormous promise. Right now, they are being used to treat cancer, but in the future, they might be able to treat heart attack, dementia, neurodegenerative diseases, ALS, Parkinson’s disease, a huge list of disorders that are untreatable right now or incurable. They might be approached by the combination of cell-based models, cell therapies, and gene editing.
TH: I know there are still some challenges right now, like gene editing has some ethical issues because people don’t know if there can be side effects after the gene editing, what are your thoughts?
AK: You know, like many other technologies there are uncertainties, and there are some issues. Some of the problems are off-target effects, that is you try to make a change in one particular gene, and while doing that you might change other genes in unexpected ways and cause complications. But we are understanding that more and more now and can make much more precise gene editing changes in just individual genes without affecting unanticipated areas of the genome. And then there are also the problems of how to gene-edit cells in a safe way. There are certain viral factors that can be used to introduce the gene editing apparatus into a cell, and sometimes if you are doing that in a patient, you can also have unwanted side effects from the vectors that you are using, often they are modified viral vectors. So, things get complicated very quickly when you start trying to treat patients, but I think these are all tractable problems and I think in time they will all be solved. It will be a terrific, very promising future when it comes to treating patients who are currently untreatable.
TH: Do you have any advice for students who want to get into this field?
AK: Yes, I think it’s actually never been a better time and I am amazed by the technologies that are available now. Gene editing that I mentioned before but also single cell approaches, the use of single cell multiomics revealing gene expression in individual cells, the molecular understanding of how individual cells are formed, how they are shaped, how they change from one stage to another, how they can be forced into different fates. It allows you to envision true Regenerative medicine, improving health by healing or replacing injured or diseased tissues. I think this is becoming possible now, so it’s a very exciting time. Anyone who has an interest in stem cell biology or new ways of treating diseases, should think about getting into a laboratory or a clinical setting. I think this time is more exciting than it’s ever been.
TH: So excited to hear that, because in school we have limited access to the current knowledge, the state-of-art. I want to know what motivates you every day to do Research and contribute to this field?
AK: Well, you know that I have been an MD/PhD, as I mentioned before, in a way, there are two different reward systems at play. In terms of the PhD and the science, it’s the discovery part that is so exciting. Going in every day and thinking that you might learn something that no one has ever known before and have a new insight into a mechanism of how something happens, why it happens. Those kinds of new insights are terrifically satisfying, very exciting. On the MD side, the ability to help patients and improve peoples’ lives is a terrific motivator. I always wanted to do that, was very driven to become a Neurologist and treat both adult and pediatric patients with neurological problems. In the last decade or so, I’ve not been treating patients so much, and have focused on the lab, but we have been moving some of our discoveries from the laboratory into the clinic. We have just started a clinical trial, of a new cell-based therapy for epilepsy in Neurona Therapeutics, which is really exciting. I am hoping it will help the patients but it’s also a chance to actually see something that started out as a project in the laboratory become translated into a therapy for patients, so that’s an achievement that has really combined my two interests, basic science, and clinical medicine. It’s a little late in life but not too late, so I’m very excited about that.
Tan Ieng Huang, Kriegstein Lab, SEP Intern, CIRM Spark Program2022
Lou Gehrig’s disease, or ALS, is a nasty degenerative condition that destroys the brain cells controlling movement. People with ALS suffer a progressive loss of ability to walk, talk, eat and breathe.
The average life expectancy for someone diagnosed with ALS is just two to five years. It has a devastating impact on the people diagnosed and their families.
On the latest episode of our podcast,Talking ‘Bout (re)Generation, we talk to two women who have suffered a loss in this fight, but who are using their experience with ALS to help others battling the disease.
Nadia Sethi became the Director of Community Engagement and Outreach at the ALS Therapy Development Institute after losing her husband to ALS.
Their courage and determination to turn a tragedy into something positive, to help others, and to hopefully play a role in finding treatments to help people with ALS, is deeply moving and inspiring.
It’s hard to think of something as being rare when it affects up to 30 million Americans and 300 million people worldwide. But the truth is there are more than 6,000 conditions – those affecting 200,000 people or fewer – that are considered rare.
Today, February 28th, is Rare Disease Day. It’s a day to remind ourselves of the millions of people, and their families, struggling with these diseases. These conditions are also called or orphan diseases because, in many cases, drug companies were not interested in adopting them to develop treatments.
At the California Institute for Regenerative Medicine (CIRM), we have no such reservations. In fact last Friday our governing Board voted to invest almost $12 million to support a clinical trial for IPEX syndrome. IPEX syndrome is a condition where the body can’t control or restrain an immune response, so the person’s immune cells attack their own healthy tissue. This leads to the development of Type 1 diabetes, severe eczema, damage to the small intestines and kidneys and failure to thrive. It’s diagnosed in infancy, most of those affected are boys, and it is often fatal.
Taylor Lookofsky (who has IPEX syndrome) and his father Brian
IPEX is one of two dozen rare diseases that CIRM is funding a clinical trial for. In fact, more than one third of all the projects we fund target a rare disease or condition. Those include:
Some might question the wisdom of investing hundreds of millions of dollars in conditions that affect a relatively small number of patients. But if you see the faces of these patients and get to know their families, as we do, you know that often agencies like CIRM are their only hope.
Dr. Maria Millan, CIRM’s President and CEO, says the benefits of one successful approach can often extend far beyond one rare disease.
“Children with IPEX syndrome clearly represent a group of patients with an unmet medical need, and this therapy could make a huge difference in their lives. Success of this treatment in this rare disease presents far-reaching potential to develop treatments for a larger number of patients with a broad array of immune disorders.”
CIRM is proud to fund and spread awareness of rare diseases and invites you to watch this video about how they affect families around the world.
MRI section of a brain affected by ALS with the front section of the brain highlighted
Amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig’s disease, is a nasty disease that steadily attacks nerve cells in the brain and spinal cord. It’s pretty much always fatal within a few years. As if that wasn’t bad enough, ALS also can overlap with a condition called frontotemporal dementia (ALS/FTD). Together these conditions cause devastating symptoms of muscle weakness along with changes in memory, behavior and personality.
Now researchers at Cambridge University in the UK have managed to grow groups of cells called “mini-brains” that mimic ALS/FTD and could lead to new approaches to treating this deadly combination.
We have written about these mini-brains before. Basically, they are created, using the iPSC method, that takes skin or blood cells from a patient with a particular condition, in this case ALS/FTD, and turns them into the kind of nerve cells in the brain affected by the disease. Because they came from someone who had ALS/FTD they display many of the characteristics of the disease and this gives researchers a great tool to study the condition.
This kind of approach has been done before and given researchers a glimpse into what is happening in the brains of people with ALS/FTD. But in the past those cells were in a kind of clump, and it wasn’t possible to get enough nutrients to the cells in the middle of the clump for the mini-brain to survive for long.
What is different about the Cambridge team is that they were able to create these mini-brains using thin, slices of cells. That meant all the cells could get enough nutrients to survive a long time, giving the team a better model to understand what is happening in ALS/FTD.
In a news release, Dr András Lakatos, the senior author of the study, said: “Neurodegenerative diseases are very complex disorders that can affect many different cell types and how these cells interact at different times as the diseases progress.
“To come close to capturing this complexity, we need models that are more long-lived and replicate the composition of those human brain cell populations in which disturbances typically occur, and this is what our approach offers. Not only can we see what may happen early on in the disease – long before a patient might experience any symptoms – but we can also begin to see how the disturbances change over time in each cell.”
Thanks to these longer-lived cells the team were able to see changes in the mini-brains at a very early stage, including damage to DNA and cell stress, changes that affected other cells which play a role in muscle movements and behavior.
Because the cells developed using the iPSC method are from a patient with ALS/FTD, the researchers were able to use them to screen many different medications to see if any had potential as a therapy. They identified one, GSK2606414, that seemed to help in reducing the build-up of toxic proteins, reduced cell stress and the loss of nerve cells.
The team acknowledge that these results are promising but also preliminary and will require much more research to verify them.
Biomedical specialist Mamadou Dialio at work in the Cedars-Sinai Biomanufacturing Center. Photo by Cedars-Sinai.
Following the race to develop a vaccine for COVID-19 has been a crash course in learning how complicated creating a new therapy is. It’s not just the science involved, but the logistics. Coming up with a vaccine that is both safe and effective is difficult enough, but then how do you make enough doses of it to treat hundreds of millions of people around the world?
That’s a familiar problem for stem cell researchers. As they develop their products they are often able to make enough cells in their own labs. But as they move into clinical trials where they are testing those cells in more and more people, they need to find a new way to make more cells. And, of course, they need to plan ahead, hoping the therapy is approved by the Food and Drug Administration, so they will need to be able to manufacture enough doses to meet the increased demand.
We saw proof of that planning ahead this week with the news that Cedars-Sinai Medical Center in Los Angeles has opened up a new Biomanufacturing Center.
Dr. Clive Svendsen, executive director of the Cedars-Sinai Board of Governors Regenerative Medicine Institute, said in a news release, the Center will manufacture the next generation of drugs and regenerative medicine therapies.
“The Cedars-Sinai Biomanufacturing Center leverages our world-class stem-cell expertise, which already serves scores of clients, to provide a much-needed biomanufacturing facility in Southern California. It is revolutionary by virtue of elevating regenerative medicine and its therapeutic possibilities to an entirely new level-repairing the human body.”
This is no ordinary manufacturing plant. The Center features nine “clean rooms” that are kept free from dust and other contaminants. Everyone working there has to wear protective suits and masks to ensure they don’t bring anything into the clean rooms.
The Center will specialize in manufacturing induced pluripotent stem cells, or iPSCs. Dhruv Sareen, PhD, executive director of the Biolmanufacturing Center, says iPSCs are cells that can be turned into any other kind of cell in the body.
“IPSCs are powerful tools for understanding human disease and developing therapies. These cells enable us to truly practice precision medicine by developing drug treatments tailored to the individual patient or groups of patients with similar genetic profiles.”
The Biomanufacturing Center is designed to address a critical bottleneck in bringing cell- and gene-based therapies to the clinic. After all, developing a therapy is great, but it’s only half the job. Making enough of it to help the people who need it is the other half.
CIRM is funding Dr. Svendsen’s work in developing therapies for ALS and other diseases and disorders.
Having grown up in an era where to find your way around you had to use paper maps, a compass and a knowledge of the stars (OK, I’m not actually that old!) I’m forever grateful to whoever invented the GPS. It’s a lifesaver, and I daresay has also saved more than a few marriages!
Having a way to guide people where they need to be is amazing. Now researchers at Sanford Burnham Prebys Medical Discovery Institute have come up with a similar tool for stem cells. It’s a drug that can help guide stem cells to go where they need to go, to repair damaged tissue and improve the healing process.
In a news release Evan Snyder, MD, PhD, the senior author of the study, explained in wonderfully simply terms what they have done:
“The ability to instruct a stem cell where to go in the body or to a particular region of a given organ is the Holy Grail for regenerative medicine. Now, for the first time ever, we can direct a stem cell to a desired location and focus its therapeutic impact.”
More than a decade ago Snyder and his team discovered that when our body suffers an injury the result is often inflammation and that this then sends out signals for stem cells to come and help repair the damage. This is fine when the problem is a cut or sprain, short term issues in need of a quick fix. But what happens if it’s something more complex, such as a heart attack or stroke where the need is more long term.
In the study, funded in part by CIRM, the team took a molecule, called CXCL12, known to help guide stem cells to damaged tissue, and used it to create a drug called SDV1a. Snyder says this new drug has several key properties.
“Since inflammation can be dangerous, we modified CXCL12 by stripping away the risky bit and maximizing the good bit. Now we have a drug that draws stem cells to a region of pathology, but without creating or worsening unwanted inflammation.”
To test the drug to see how well it worked the team implanted SDV1a and some human brain stem cells into mice with Sandhoff disease, a condition that progressively destroys cells in the brain and spinal cord. They were able to demonstrate that the drug helped the stem cells migrate to where they were needed and to help in repairing the damage. The treated mice had a longer lifespan and better motor function, as well as developing symptoms later than untreated mice.
The team is now testing this drug to see if it has any impact on ALS, also known as Lou Gehrig’s disease. And Snyder says there are other areas where it could prove effective.
“We are optimistic that this drug’s mechanism of action may potentially benefit a variety of neurodegenerative disorders, as well as non-neurological conditions such as heart disease, arthritis and even brain cancer. Interestingly, because CXCL12 and its receptor are implicated in the cytokine storm that characterizes severe COVID-19, some of our insights into how to selectively inhibit inflammation without suppressing other normal processes may be useful in that arena as well.”
CIRM’s President & CEO, Dr. Maria Millan, says this kind of work highlights the important role the stem cell agency plays, in providing long-term support for promising but early stage research.
“Thanks to decades of investment in stem cell science, we are making tremendous progress in our understanding of how these cells work and how they can be harnessed to help reverse injury or disease. Dr. Snyder’s group has identified a drug that could boost the ability of neural stem cells to home to sites of injury and initiate repair. This candidate could help speed the development of stem cell treatments for conditions such as spinal cord injury and Alzheimer’s disease.”
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.”
An Organ-Chip used in the study to create a blood-brain barrier (BBB).
The brain is a complex part of the human body that allows for the formation of thoughts and consciousness. In many ways it is the essence of who we are as individuals. Because of its importance, our bodies have developed various layers of protection around this vital organ, one of which is called the blood-brain barrier (BBB).
The BBB is a thin border of various cell types around the brain that regulate what can enter the brain tissue through the bloodstream. Its primary purpose is to prevent toxins and other unwanted substances from entering the brain and damaging it. Unfortunately this barrier can also prevent helpful medications, designed to fix problems, from reaching the brain.
Several brain disorders, such as Amyotrophic Lateral Sclerosis (ALS – also known as Lou Gehrig’s disease), Parkinson’s Disease (PD), and Huntington’s Disease (HD) have been linked to defective BBBs that keep out critical biomolecules needed for healthy brain activity.
In a CIRM-funded study, a team at Cedars-Sinai Medical Center created a BBB through the use of stem cells and an Organ-Chip made from induced pluripotent stem cells (iPSCs). These are a specific type of stem cells that can turn into any type of cell in the body and can be generated from a person’s own cells. In this study, iPSCs were created from adult blood samples and used to make the neurons and other supporting cells that make up the BBB. These cells were then placed inside an Organ-Chip which recreates the environment that cells normally experience within the human body.
Inside the 3-D Organ-Chip, the cells were able to form a BBB that functions as it does in the body, with the ability to block entry of certain drugs. Most notably, when the BBB was generated from cell samples of patients with HD, the BBB malfunctioned in the same way that it does in patients with the disease.
These findings expand the potential for personalized medicine for various brain disorders linked to problems in the BBB. In a press release, Dr. Clive Svendsen, director of the Cedars-Sinai Board of Governors Regenerative Medicine Institute and senior author of the study, was quoted as saying,
“The study’s findings open a promising pathway for precision medicine. The possibility of using a patient-specific, multicellular model of a blood barrier on a chip represents a new standard for developing predictive, personalized medicine.”
The full results of the study were published in the scientific journal Cell Stem Cell.
A descriptive illustration of Amyotrophic Lateral Sclerosis (ALS), also known as Lou Gehrig’s Disease. Courtesy of ALS Foundation website.
Understanding the basic biology of how a cell functions can be crucial to being able to better understand a disease and unlock a potential approach for a treatment. Stem cells are unique in that they give scientists the opportunity to create a controlled environment of cells that might be otherwise difficult to study. Dr. Eva Hedlund and a team of researchers at the Karolinska Institute in Sweden utilize a stem cell model approach to uncover findings related to Amyotrophic Lateral Sclerosis (ALS), also known as Lou Gehrig’s Disease.
ALS is a progressive neurodegenerative disease that destroys motor neurons, a type of nerve cell, that are important for voluntary muscle movement. When motor neurons can no longer send signals to the muscles, the muscles begin to deteriorate, a process formally known as atrophy. The progressive atrophy leads to muscle paralysis, including those in the legs and feet, arms and hands, and those that control swallowing and breathing. It affects about 30,000 people in the United States alone, with 5,000 new cases diagnosed each year. There is currently no cure.
In a previous study, researchers at the Karolinska Institute were able to successfully create oculomotor neurons from embryonic stem cells. For reasons not yet fully understood, oculomotor neurons are “ALS resilient” and can survive all stages of the disease.
In the current study, published in Stem Cell Reports, Dr. Hedlund and her team found that the oculomotor neurons they generated appeared more resilient to ALS-like degeneration when compared to spinal cord motor neurons, something commonly observed in humans. Furthermore, they discovered that their “ALS resilient” neurons generated from stem cells activate a survival-enhancing signal known as Akt, which is common in oculomotor neurons in humans and could explain their resilience. These results could potentially aid in identifying genetic targets for treatments protecting sensitive neurons from the disease.
In a press release, Dr. Hedlund is quoted as saying,
“This cell culture system can help identify new genes contributing to the resilience in oculomotor neurons that could be used in gene therapy to strengthen sensitive motor neurons.”
CIRM is currently funding two clinical trials for ALS, one of which is being conducted by Cedars-Sinai Medical Center and the other by Brainstorm Cell Therapeutics. The latter of the trials is currently recruiting patients and information on how to enroll can be found here.
The Stem Cellar 