Every year California performs around 100 kidney transplants in children but, on average, around 50 of these patients will have their body reject the transplant. These children then have to undergo regular dialysis while waiting for a new organ. Even the successful transplants require a lifetime of immunosuppression medications. These medications can prevent rejection but they also increase the risk of infection, gastrointestinal disease, pancreatitis and cancer.
Dr. Alice Bertaina and her team at Stanford University were awarded $11,998,188 to test an approach that uses combined blood stem cell (HSC) and kidney transplantation with the goal to improve outcomes with kidney transplantation in children. This approach seeks to improve on the blood stem cell preparation through an immune-based purification process.
In this approach, the donor HSC are transplanted into the patient in order to prepare for the acceptance of the donor kidney once transplanted. Donor HSC give rise to cells and conditions that re-train the immune system to accept the kidney. This creates a “tolerance” to the transplanted kidney providing the opportunity to avoid long-term need for medications that suppress the immune system.
Pre-clinical data support the idea that this approach could enable the patient to stop taking any immunosuppression medications within 90 days of the surgery.
Dr. Maria T. Millan, President and CEO of CIRM, a former pediatric transplant surgeon and tolerance researcher states that “developing a way to ensure long-term success of organ transplantation by averting immune rejection while avoiding the side-effects of life-long immunosuppression medications would greatly benefit these children.”
The CIRM Board also awarded $7,141,843 to Dr. Ivan Kingand Tachyon Therapeutics, Inc to test a drug showing promise in blocking the proliferation of cancer stem cells in solid tumors such as colorectal and gastrointestinal cancer.
Patients with late-stage colorectal cancer are typically given chemotherapy to help stop or slow down the progression of the disease. However, even with this intervention survival rates are low, usually not more than two years.
Tachyon’s medication, calledTACH101, is intended to target colorectal cancer (CRC) stem cells as well as the bulk tumor by blocking an enzyme called KDM4, which cancer stem cells need to grow and proliferate.
In the first phase of this trial Dr. King and his team will recruit patients with advanced or metastatic solid tumors to assess the safety of TACH101, and determine what is the safest maximum dose. In the second phase of the trial, patients with gastrointestinal tumors and colorectal cancer will be treated using the dose determined in the first phase, to determine how well the tumors respond to treatment.
The CIRM Board also awarded $5,999,919 to Dr. Natalia Gomez-Ospina and her team at Stanford University for a late-stage preclinical program targeting Severe Mucopolysaccharidosis type 1, also known as Hurler syndrome. This is an inherited condition caused by a faulty gene. Children with Hurler syndrome lack an enzyme that the body needs to digest sugar. As a result, undigested sugar molecules build up in the body, causing progressive damage to the brain, heart, and other organs. There is no effective treatment and life expectancy for many of these children is only around ten years.
Dr. Gomez-Ospina will use the patient’s own blood stem cells that have been genetically edited to restore the missing enzyme. The goal of this preclinical program is to show the team can manufacture the needed cells, to complete safety studies and to apply to the US Food and Drug Administration for an Investigational New Drug (IND), the authorization needed to begin a clinical trial in people.
Finally the Board awarded $20,401,260 to five programs as part of its Translational program. The goal of the Translational program is to support promising stem cell-based or gene projects that accelerate completion of translational stage activities necessary for advancement to clinical study or broad end use. Those can include therapeutic candidates, diagnostic methods or devices and novel tools that address critical bottlenecks in research.
The successful applicants are:
APPLICATION
TITLE
PRINCIPAL INVESTIGATOR – INSTITUTION
AMOUNT
TRAN4-14124
Cell Villages and Clinical Trial in a Dish with Pooled iPSC-CMs for Drug Discovery
Nikesh Kotecha — Greenstone Biosciences
$1,350,000
TRAN1-14003
Specific Targeting Hypoxia Metastatic Breast Tumor with Allogeneic Off-the-Shelf Anti-EGFR CAR NK Cells Expressing an ODD domain of HIF-1α
Jianhua Yu — Beckman Research Institute of City of Hope
$6,036,002
TRAN1-13983
CRISPR/Cas9-mediated gene editing of Hematopoietic stem and progenitor cells for Friedreich’s ataxia
Stephanie Cherqui — University of California, San Diego
$4,846,579
TRAN1-13997
Development of a Gene Therapy for the Treatment of Pitt Hopkins Syndrome (PHS) – Translating from Animal Proof of Concept to Support Pre-IND Meeting
Allyson Berent — Mahzi Therapeutics
$4,000,000
TRAN1-13996
Overcoming resistance to standard CD19-targeted CAR T using a novel triple antigen targeted vector
William J Murphy — University of California, Davis
The world of stem cell research is advancing rapidly, with new findings and discoveries seemingly every week. And yet some things that we knew years ago are still every bit as relevant today as they were then.
Take for example a TEDx talk by Dr. Daniel Kota, a stem cell researcher and the Director, Cellular Therapy – Research and Development at Houston Methodist.
Dr. Kota’s talk is entitled: “Promises and Dangers of Stem Cell Therapies”. In it he talks about the tremendous potential of stem cells to reverse the course of disease and help people battle previously untreatable conditions.
But he also warns about the gap between what the science can do, and what people believe it can do. He says too many people have unrealistic expectations of what is available right now, fueled by many unscrupulous snake oil salesmen who open clinics and offer “treatments” that are both unproven and unapproved by the Food and Drug Administration.
He says we need to “bridge the gap between stem cell science and society” so that people have a more realistic appreciation of what stem cells can do.
Sadly, as the number of clinics peddling these unproven therapies grows in the US, Dr. Kota’s message remains all too timely.
A study by Stanford Medicine researchers in older mice may lead to treatments that help seniors regain muscle strength lost to aging.
Muscle stem cells—which are activated in response to muscle injury to regenerate damaged muscle tissue—lose their potency with age. A study from the National Health and Nutrition Examination Survey showed that five percent of adults aged 60 and over had weak muscle strength, and thirteen percent had intermediate muscle strength.
Now, researchers at Stanford Medicine are seeing that old mice regain the leg muscle strength of younger animals after receiving an antibody treatment that targets a pathway mediated by a molecule called CD47.
CD47 is a protein found on the surface of many cells in the body. Billed as the “don’t eat me” molecule, it is better known as a target for cancer immunotherapy. It’s common on the surface of many cancer cells and protects them from immune cells that patrol the body looking for dysfunctional or abnormal cells.
Stanford researchers are finding that old muscle stem cells may use a similar approach to avoid being targeted by the immune system.
It’s been difficult to determine why muscle stem cells lose their ability to divide rapidly in response to injury or exercise as they age. Dr. Ermelinda Porpiglia, the lead author of the study, used a technique called “single-cell mass cytometry” to study mouse muscle stem cells.
Using the technique, Porpiglia focused on CD47, and found that the molecule was found at high levels on the surface of some muscle stem cells in older mice, but at lower levels in younger animals. Porpiglia also found that high levels of CD47 on the surface of muscle stem cells correlate with a decrease in their function.
“This finding was unexpected because we primarily think of CD47 as an immune regulator,” Porpiglia said. “But it makes sense that, much like cancer cells, aged stem cells might be using CD47 to escape the immune system.”
Testing an Antibody
Further investigation revealed that a molecule called thrombospondin, which binds to CD47 on the surface of the muscle stem cells, suppresses the muscle stem cells’ activity.
Porpiglia showed that an antibody that recognizes thrombospondin and blocks its ability to bind to CD47 dramatically affected the function of muscle stem cells. Cells from older animals divided more robustly when growing in a laboratory dish in the presence of the antibody, and when the antibody was injected into the leg muscles of old mice the animals developed bigger and stronger leg muscles than control animals.
When given prior to injury, the antibody helped the aged animals recover in ways similar to younger mice.
Porpiglia said, “We are hopeful that it might one day be possible to inject an antibody to thrombospondin at specific sites in the body to regenerate muscle in older people or to counteract functional problems due to disease or surgery.”
These results are significant because they could one day make it possible to boost muscle recovery in humans after surgery and reduce the decline in muscle strength as people age, but researchers say more work is needed.
“Rejuvenating the muscle stem cell population in older mice led to a significant increase in strength,” said Dr. Helen Blau, a senior author of the study. “This is a localized treatment that could be useful in many clinical settings, although more work needs to be done to determine whether this approach will be safe and effective in humans.”
CIRM has previously funded work with researchers using CD47 that led to clinical trials targeting cancer. You can read about that work here and here. That work led to the creation of a company, Forty Seven Inc, which was eventually bought by Gilead for $4.9 billion.
This brings the total number of CIRM funded clinical trials to 83.
$11,999,984 was awarded to Dr. Jana Portnow at the Beckman Research Institute of City of Hope. They are using Neural stem cells (NSCs) as a form of delivery vehicle to carry a cancer-killing virus that specifically targets brain tumor cells.
Glioblastoma is the most common malignant primary brain tumor in adults and each year about 12,000 Americans are diagnosed. The 5-year survival rate is only about 10%.
The current standard of care involves surgically removing the tumor followed by radiation, chemotherapy, and alternating electric field therapy. Despite these treatments, survival remains low.
The award to Dr. Portnow will fund a clinical trial to assess the safety and effectiveness of this stem cell-based treatment for Glioblastoma.
The Board also awarded $3,111,467 to Dr. Boris Minev of Calidi Biotherapeutics. This award is in the form of a CLIN1 grant, with the goal of completing the testing needed to apply to the Food and Drug Administration (FDA) for permission to start a clinical trial in people.
This project uses donor fat-derived mesenchymal stem cells that have been loaded with oncolytic virus to target metastatic melanoma, triple negative breast cancer, and advanced head & neck squamous cell carcinoma.
“There are few options for patients with advanced solid tumor cancers such as glioblastoma, melanoma, breast cancer, and head & neck cancer,” says Maria T. Millan, M.D., President and CEO of CIRM. “Surgical resection, chemotherapy and radiation are largely ineffective in advanced cases and survival typically is measured in months. These new awards will support novel approaches to address the unmet medical needs of patients with these devastating cancers.”
The CIRM Board also voted to approve awarding $71,949,539 to expand the CIRM Alpha Clinics Network. The current network consists of six sites and the Board approved continued funding for those and added an additional three sites. The funding is to last five years.
The goal of the Alpha Clinics award is to expand existing capacities for delivering stem cell, gene therapies and other advanced treatment to patients. They also serve as a competency hub for regenerative medicine training, clinical research, and the delivery of approved treatments.
Each applicant was required to submit a plan for Diversity, Equity and Inclusion to support and facilitate outreach and study participation by underserved and disproportionately affected populations in the clinical trials they serve.
The successful applicants are:
Application
Program Title
Institution/Principal Investigator
Amount awarded
INFR4-13579
The Stanford Alpha Stem Cell Clinic
Stanford University – Matthew Porteus
$7,997,246
INFR4-13581
UCSF Alpha Stem Cell Clinic
U.C. San Francisco – Mark Walters
$7,994,347
INFR4-13586
A comprehensive stem cell and gene therapy clinic to advance new therapies for a diverse patient population in California
Cedars-Sinai Medical Center – Michael Lewis
$7,957,966
INFR4-13587
The City of Hope Alpha Clinic: A roadmap for equitable and inclusive access to regenerative medicine therapies for all Californians
City of Hope – Leo Wang
$8,000,000
INFR4-13596
Alpha Stem Cell Clinic for Northern and Central California
U.C. Davis – Mehrdad Abedi
$7,999,997
INFR4-13685
Expansion of the Alpha Stem Cell and Gene Therapy Clinic at UCLA
U.C. Los Angeles – Noah Federman
$8,000,000
INFR4-13878
Alpha Clinic Network Expansion for Cell and Gene Therapies
University of Southern California – Thomas Buchanan
$7,999,983
INFR4-13952
A hub and spoke community model to equitably deliver regenerative medicine therapies to diverse populations across four California counties
U.C. Irvine – Daniela Bota
$8,000,000
INFR4-13597
UC San Diego Health CIRM Alpha Stem Cell Clinic
U.C. San Diego – Catriona Jamieson
$8,000,000
The Board also unanimously, and enthusiastically, approved the election of Maria Gonzalez Bonneville to be the next Vice Chair of the Board. Ms. Bonneville, the current Vice President of Public Outreach and Board Governance at CIRM, was nominated by all four constitutional officers: the Governor, the Lieutenant Governor, the Treasurer and the Controller.
In supporting the nomination, Board member Ysabel Duron said: “I don’t think we could do better than taking on Maria Gonzalez Bonneville as the Vice Chair. She is well educated as far as CIRM goes. She has a great track record; she is empathetic and caring and will be a good steward for the taxpayers to ensure the work we do serves them well.”
In her letter to the Board applying for the position, Ms. Bonneville said: “CIRM is a unique agency with a large board and a long history. With my institutional knowledge and my understanding of CIRM’s internal workings and processes, I can serve as a resource for the new Chair. I have worked hand-in-hand with both the Chair and Vice Chair in setting agendas, prioritizing work, driving policy, and advising accordingly. I have worked hard to build trusted relationships with all of you so that I could learn and understand what areas were of the most interest and where I could help shed light on those particular programs or initiatives. I have also worked closely with Maria Millan for the last decade, and greatly enjoy our working relationship. In short, I believe I provide a level of continuity and expertise that benefits the board and helps in times of transition.”
In accepting the position Ms. Bonneville said: “I am truly honored to be elected as the Vice Chair for the CIRM Board. I have been a part of CIRM for 11 years and am deeply committed to the mission and this new role gives me an opportunity to help support and advance that work at an exciting time in the Agency’s life. There are many challenges ahead of us but knowing the Board and the CIRM team I feel confident we will be able to meet them, and I look forward to helping us reach our goals.”
Ms. Bonneville will officially take office in January 2023.
The vote for the new Chair of CIRM will take place at the Board meeting on December 15th.
Our 2021-22 Annual Report is now online. It’s filled with information about the work we have done over the last year (we are on a fiscal calendar year from July 1 – June 30), the people who have helped us do that work, and some of the people who have benefited from that work. One of those is Dr. Alysson Muotri, a professor in the Departments of Pediatrics and Cellular & Molecular Medicine at the University of California, San Diego.
Dr. Alysson Muotri, in his lab at UCSD
For Dr. Alysson Muotri, trying to unlock the secrets of the brain isn’t just a matter of scientific curiosity, it’s personal. He has a son with autism and Dr. Muotri is looking for ways to help him, and millions of others like him around the world.
He created the Tooth Fairy project where parents donated more than 3,000 baby teeth from children with autism and children who are developing normally. Dr. Muotri then turned cells from those teeth into neurons, the kind of brain cell affected by autism. He is using those cells to try and identify how the brain of a child with autism differs from a child who is developing normally.
“We’ve been using cells from this population to see what are the alterations (in the gene) and if we can revert them back to a normal state. If you know the gene that is affected, and autism has a strong genetic component, by genome sequencing you can actually find what are the genes that are affected and in some cases there are good candidates for gene therapy. So, you just put the gene back. And we can see that in the lab where we are correcting the gene that is mutated, the networks start to function in a way that is more neurotypical or normal. We see that as highly promising, there’s a huge potential here to help those individuals.”
He is also creating brain organoids, three-dimensional structures created from stem cells that mimic some of the actions and activities of the brain. Because these are made from human cells, not mice or other animals, they may be better at indicating if new therapies have any potential risks for people.
“We can test drugs in the brain organoids of the person and see if it works, see if there’s any toxicity before you actually give the drug to a person, and it will save us time and money and will increase our knowledge about the human brain.”
He says he still gets excited seeing how these cells work. “It’s amazing, it’s a miracle. Every time I see it, it’s like seeing dolphins in the sea because it’s so beautiful.”
Dr. Muotri is also a big proponent of diversity, equity and inclusion in scientific research. He says in the past it was very much a top-down model with scientists deciding what was important. He says we need to change that and give patients and communities a bigger role in shaping the direction of research.
“I think this is something we scientists have to learn, how to incorporate patients in our research. These communities are the ones we are studying, and we need to know what they want and not assume that what we want is what they want. They should be consulted on our grants, and they should participate in the design of our experiments. That is the future.”
Growing up Veronica McDougall thought everyone saw the world the way she did; blurry, slightly out-of-focus and with tunnel vision. As she got older her sight got worse and even the strongest prescription glasses didn’t help. When she was 15 her brother tried teaching her to drive. One night she got into the driver’s seat to practice and told him she couldn’t see anything. Everything was just black. After that she stopped driving.
Veronica says high school was really hard for her, but she managed to graduate and go to community college. As her vision deteriorated, she found it was increasingly hard to read the course work and impossible to see the assignments on the blackboard. Veronica says she was lucky to have some really supportive teachers — including the now First Lady Jill Biden — but eventually she had to drop out.
Getting a diagnosis
When she was 24, she went to see a specialist who told her she had retinitis pigmentosa, a rare degenerative condition that would eventually leave her legally blind. She says it felt like a death sentence. “All of my dreams of becoming a nurse, of getting married, of having children, of traveling – it all just shattered in that moment.”
Veronica says she went from being a happy, positive person to an angry depressed one. She woke up each morning terrified, wondering, “Is this the day I go blind?”
Then her mother learned about a CIRM-funded clinical trial with a company called jCyte. Veronica applied to be part of it, was accepted and was given an injection of stem cells in her left eye. She says over the course of a few weeks, her vision steadily improved.
“About a month after treatment, I was riding in the car with my mom and suddenly, I realized I could see her out of the corner of my eye while looking straight ahead. That had never, ever happened to me before. Because, I had been losing my peripheral vision at a young age without realizing that until up to that point, I had never had that experience.”
A second chance at life
She went back to college, threw herself into her studies, started hiking and being more active. She says it was as if she was reborn. But in her senior year, just as she was getting close to finishing her degree, her vision began to deteriorate again. Fortunately, she was able to take part in a second clinical trial, and this time her vision came back stronger than ever.
“I’m so grateful to the researchers who gave me my sight back with the treatment they have worked their entire lives to develop. I am forever grateful for the two opportunities to even receive these two injections and to be a part of an amazing experience to see again. I feel so blessed! Thank you for giving me my life back.”
And in getting her life back, Veronica had a chance to give life. When she was at college she met and starting dating Robert, the man who was to become her partner. They now have a little boy, Elliott.
As for the future, Veronica hopes to get a second stem cell therapy to improve her vision even further. Veronica’s two treatments were in her left eye. She is hoping that the Food and Drug Administration will one day soon approve jCyte’s therapy, so that she can get the treatment in her right eye. Then, she says, she’ll be able to see the world as the rest of us can.
Dr. Jill Helms, and associate! Photo courtesy Stanford University
Jill Helms is not your average Stanford University faculty member. Yes, she is a professor in the Department of Surgery. Yes, she has published lots of scientific studies. Yes, she is a stem cell scientist (funded by CIRM). And yes, she is playing a leading role in Ankasa Regenerative Therapeutics, a company focused on tissue repair and regeneration. But she is so much more than all that.
She is a brilliant public speaker, a fashionista, and has ridden her horse to work (well, Stanford is referred to as The Farm, so why not!) and she lives on a farm of her own called “Follow Your Bliss.” The name comes from philosopher Joseph Campbell who wrote, “If you follow your bliss, you put yourself on a kind of path that has been there all the while, waiting for you. And the life you ought to be living is the one you are living.”
Dr. Helms says that pretty much sums up her life. She says she feels enormously blessed.
Well, we felt enormously blessed when she agreed to sit down with us and chat about her work, her life and her love of fashion for the California Institute for Regenerative Medicine podcast, Talking ‘Bout (re)Generation.
A urethral stricture is scarring of the tube that carries urine out of the body. If left untreated it can be intensely painful and lead to kidney stones and infections. That’s why the governing Board of the California Institute for Regenerative Medicine (CIRM) is investing more than $3.8 million in a Phase 1 clinical trial to create a stem cell-based therapy for the condition.
When a scar, or stricture, forms along the urethra it impedes the flow of urine and causes other complications. James Yoo, M.D., Ph.D., and his team at Wake Forest University Health Sciences will use epithelial and smooth muscle cells, taken from the patient’s bladder, and layer them on to a synthetic tubular scaffold. The tube will then be surgically implanted inside the urethra.
The goal is for the progenitor cells to support self-renewal of the tissue and for the entire structure to become integrated into the surrounding tissue and become indistinguishable from it, restoring normal urinary function. Dr. Yoo and his team believe their approach has the potential to be effective for at least a decade.
“While not immediately life-threatening, urethral strictures lead to multiple health complications that impair quality of life and predispose to kidney dysfunction,” says Dr. Maria T. Millan, President and CEO of CIRM. “Developing an effective and durable treatment would significantly impact lives and has the potential to decrease the cumulative healthcare costs of treating recurrent kidney stones, infections and downstream kidney complications, especially of long-segment urethral strictures.”
Sean Entin, stroke survivor and founder of Stroke Hacker
The word “miraculous” gets tossed around a lot in the world of medicine, mostly by people who have made an unexpected recovery from a deadly or life-threatening condition. In Sean Entin’s case calling his recovery from an almost-fatal stroke could be called miraculous, but I think you would also have to say it’s due to hard work, determination, and an attitude that never even considered giving up.
Sean had a stroke in 2011. Doctors didn’t think he’d survive. He was put into a coma and underwent surgery to create an opening in his skull to give his brain time and space to heal. When he woke he couldn’t walk or talk, couldn’t count. Doctors told him he would never walk again.
They didn’t know Sean. Fast forward to today. Sean is active, has completed two 5k races – that’s two more than me – and has created Stroke Hacker, a program designed to help others going through what he did.
Sean is a remarkable man, which is why I sat down to chat with him for the latest episode of the California Institutes for Regenerative Medicine’s podcast, ‘Talking ‘Bout (re)Generation’.
He is a fascinating man, and he makes for fascinating company. Enjoy the podcast.
The California Institute for Regenerative Medicine (CIRM) has invested more than $80 million in stroke research, including one clinical trial currently underway.
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
The Stem Cellar 