Can stem cells help people recovering from a stroke? You asked, and the experts answered

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We recently held our first ever Facebook Live event. It was focused on the use of stem cells and recovery from a stroke and featured three great guests: Dr. Gary Steinberg, chief of Neurosurgery at Stanford, Sonia Coontz, a patient of Dr. Steinberg’s, and CIRM’s own Science Officer Dr. Lila Collins.

We had an amazing response from people during the event and in the days since then with some 6,750 people watching the video and almost 1,000 people reacting by posting a comment or sharing it with friends. It was one of the most successful things we have ever done on Facebook so it’s not surprising that we plan on doing many more Facebook Live ‘Ask the Expert’ events in the future. We will post more details of that as we finalize them.

We tried to cover as many topics as possible during the hour but there were simply too many questions for us to get to all of them. So here is a recap of the key issues we covered, and a few we didn’t have a chance to answer.

Let’s start with Dr. Steinberg’s explanation of the research that led to his current clinical trial:

Dr. Steinberg: “I got interested in this about 18 years ago when I took human cells and transplanted them into rodent models of stroke. What we found was that when we transplanted those cells into the stroke region, the core of the stroke, they didn’t survive very well but when we moved them a few millimeters away from the stroke they not only survived but they migrated to the stroke.

The reason they migrate is that the stem cells have receptors on them that interact with chemicals given off by the stroke environment and that’s why they migrate to the stroke site. And when they get to the site they can turn into different kinds of cells. Very importantly we found these mice and rats that had behavioral problems – walking, moving – as a result of the stroke, we found we could improve their neurological outcomes with the stem cells.

With the help of CIRM, which has been very generous, we were fortunate enough to receive about $24 million in funding over the last 8 years, from 2010, to move this therapy into the clinic to understand the basic mechanisms of the recovery and to start clinical trials

One of the surprising things was that our initial notion was that the cells we transplanted into the brains would initially turn into the cells in the brain affected by the stroke and reconstitute those circuits. We were shocked to find that that was not what was happening, that only a few of the transplanted cells turned into neurons. The way they were recovering function was by secreting very powerful growth factors and molecules and proteins that enhanced native recovery or the ability of the normal brain to recover itself. Some of these processes included outgrowth of neurons, new connections, new synapses, not from the stem cells but from the native cells already in the brain.

This is not cell replacement but enhancing native recovery and, in a simple sense, what the cells are doing, we believe, is to change the adult brain, which has a hard time recovering from a stroke, into an infant brain and infants recover very well after a stroke.”

All this work was focused on ischemic strokes, where a blockage cuts off blood flow to the brain. But people like Cheryl Ward wanted to know: “Will this work for hemorrhagic stroke?” That’s where a blood vessel in the brain leaks or ruptures.

Dr. Steinberg: “I suspect we will be generalizing this therapy into hemorrhagic patients very, very soon and there’s no reason why it shouldn’t work there. The reason we didn’t start there is that 85% of strokes are ischemic and only 15% are hemorrhagic so it’s a smaller population but a very, very important population because when patients have a hemorrhage from a stroke they are often more seriously disabled than from ischemic.”

Dr. Lila Collins: “I would like to highlight one trial for hemorrhagic stroke with the Mayo Clinic and that’s using mesenchymal stem cells (normally found in bone marrow or blood). It’s an early stage, Phase 1 safety study in patients with recent cerebral hemorrhage.  They are looking at improvements in neurological function and patients have to be treated within 72 hours after the stroke.”

Dr. Steinberg explained that because it’s more difficult to enroll patients within 72 hours of a stroke that we may end up offering a combination of therapies spread out over months or even years.

Dr. Steinberg: “It may be that and we may figure this out in the next 5 to 10 years, that you might want to treat patients acutely (right away) with an intravenous therapy in the first 72 hours and then you might want to come in again sub-acutely within a few months, injecting the cells into the brain near the stroke, and then maybe come in chronically a few years later if there are still problems and place the cells directly in the brain. So, lots of ways to think about how to use this in the future.”

James Russell suffered a stroke in 2014 and wrote:

“My left side was affected. My vision was also impacted. Are any stroke patients being given stem cells seeing possible improvement in visual neglect?”

Dr. Steinberg: “We don’t know the answer to that yet, it’s quite possible. It’s true these vision circuits are not dead and could be resurrected. We have not targeted visual pathways in our work, we have targeted motor functions, but I would also be optimistic that we could target patients who have vision problems from stroke. It’s a very important area.

A number of people wondered if stem cells can help people recovering from a stroke can they also help people with other neurological conditions.

Hanifa Gaphoor asked “What about Parkinson’s disease?” and Ginnievive Patch wondered “Do you feel hopeful for neurological illnesses like Huntington’s disease and ALS? Dr. Steinberg was cautiously optimistic.

Dr. Steinberg: “We’ve extended this kind of treatment not just for ischemic stroke but into traumatic brain injury (TBI) and we just completed a trial for patients with chronic TBI or who have suffered a trauma to the brain. Many other indications may be possible. In fact, now that we know these circuits are not dead or irreversibly injured, we believe we could even extend this to neurodegenerative diseases like ALS, Parkinson’s, maybe even to Alzheimer’s disease in the future. So, lots of hope but we don’t want to oversell this, and we want to make sure this is done in a rigorous fashion.”

Several people had questions about using their own adipose, or fat stem cells, in therapies being offered at clinics around the US and in other countries. Cheri Hicks asked: “I’m curious if adipose stem cell being used at clinics at various places is helpful or beneficial?”

Dr. Steinberg: “I get emails or calls from patients every week saying should I go to Russia, India or Mexico and get stem cell transplants which are done not as part of a rigorous trial and I discourage patients from getting stem cells that are not being given in a controlled fashion. For one thing, patients have been getting hurt by these treatments in these clinics; they have developed tumors and infections and other problems. In many cases we don’t even know what the cells are, there’s not published information and the patients pay cash for this, of course.”

At CIRM we also worry about people going to clinics, in the US and in other countries, where they are getting therapies that have not been approved by the US Food and Drug Administration (FDA) or other appropriate regulatory bodies. That’s why we have created this page on our website to help people who want a stem cell therapy but don’t know what to look for in a clinical trial or what questions to ask to make sure it’s a legitimate trial, one that’s been given the go-ahead by the FDA.

Bret Ryan asked: “What becomes of the implanted cells?”

Dr. Steinberg: We found after transplanting the cells, one week after the transplant, we see a new abnormality in the premotor cortex, the area of the brain that controls motor function. We saw a new abnormality there or a new signal that disappears after a month and never comes back. But the size of that temporary abnormality after one week correlates very closely with the degree of recovery after six months, one year and two years.

One of the interesting things is that it doesn’t seem to be necessary for the cells to survive long term to have beneficial effects. The cells we used in the SanBio trial don’t survive more than a month and yet they seem to aid recovery function in our pilot studies which is sustained for years.”

And of course, many people, such as Karen Smart, wanted to know how they could get the therapy. Right now, the clinical trial is fully enrolled but Stanford is putting together a waiting list for future trials. If you are interested and would like more information, please email: stemcellstudy@stanford.edu.

Sonia Coontz, the patient who was also a key part of the Facebook Live event, has an amazing story to tell. She was left devastated, physically and emotionally, after having a stroke. But then she heard about Dr. Steinberg’s clinical trial and it changed her life. Here’s her story.

We were thrilled to receive all of your comments and questions during our first Facebook Live event. It’s this kind of dialogue between scientists, patients and the public that will be critical for the continued support of our mission to accelerate stem cell treatments to patients with unmet medical needs.

Due to the response, we plan to regularly schedule these “Ask the Expert” events. What disease area would you like us to focus on next time? Leave us a comment or email info@cirm.ca.gov

 

Friday Stem Cell Round: Ask the Expert Facebook Live, Old Brain Cells Reveal Insights and Synthetic Development

Stem Cell Photo of the Week: We’re Live on Facebook Live!

Our stem cell photo of the week is a screenshot from yesterday’s Facebook Live event: “Ask the Expert: Stem Cells and Stroke”. It was our first foray into Facebook Live and, dare I say, it was a success with over 150 comments and 4,500 views during the live broadcast.

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Screen shot of yesterday’s Facebook Live event. Panelists included (from top left going clockwise): Sonia Coontz, Kevin McCormack, Gary Steinberg, MD, PhD and Lila Collins, PhD.

Our panel included Dr. Gary Steinberg, MD, PhD, the Chair of Neurosurgery at Stanford University, who talked about promising clinical trial results testing a stem cell-based treatment for stroke. Lila Collins, PhD, a Senior Science Officer here at CIRM, provided a big picture overview of the latest progress in stem cell therapies for stroke. Sonia Coontz, a patient of Dr. Steinberg’s, also joined the live broadcast. She suffered a devastating stroke several years ago and made a remarkable recovery after getting a stem cell therapy. She had an amazing story to tell. And Kevin McCormack, CIRM’s Senior Director of Public Communications, moderated the discussion.

Did you miss the Facebook Live event? Not to worry. You can watch it on-demand on our Facebook Page.

What other disease areas would you like us to discuss? We plan to have these Ask the Expert shows on a regular basis so let us know by commenting here or emailing us at info@cirm.ca.gov!

Brain cells’ energy “factories” may be to blame for age-related disease

Salk Institute researchers published results this week that shed new light on why the brains of older individuals may be more prone to neurodegenerative diseases like Parkinson’s and Alzheimer’s. To make this discovery, the team applied a technique they devised back in 2015 which directly converts skin cells into brain cells, aka neurons. The method skips the typical intermediate step of reprogramming the skin cells into induced pluripotent stem cells (iPSCs).

They collected skin samples from people ranging in age from 0 to 89 and generated neurons from each. With these cells in hand, the researchers then examined how increased age affects the neurons’ mitochondria, the structures responsible for producing a cell’s energy needs. Previous studies have shown a connection between faulty mitochondria and age-related disease.

While the age of the skin cells had no bearing on the health of the mitochondria, it was a different story once they were converted into neurons. The mitochondria in neurons derived from older individuals clearly showed signs of deterioration and produced less energy.

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Aged mitochondria (green) in old neurons (gray) appear mostly as small punctate dots rather than a large interconnected network. Credit: Salk Institute.

The researchers think this stark difference in the impact of age on skin cells vs. neurons may occur because neurons have higher energy needs. So, the effects of old age on mitochondria only become apparent in the neurons. In a press release, Salk scientist Jerome Mertens explained the result using a great analogy:

“If you have an old car with a bad engine that sits in your garage every day, it doesn’t matter. But if you’re commuting with that car, the engine becomes a big problem.”

The team is now eager to use this method to examine mitochondrial function in neurons derived from Alzheimer’s and Parkinson’s patient skin samples and compared them with skin-derived neurons from similarly-aged, healthy individuals.

The study, funded in part by CIRM, was published in Cell Reports.

“Synthetically” Programming embryo development

One of the most intriguing, most fundamental questions in biology is how an embryo, basically a non-descript ball of cells, turns into a complex animal with eyes, a brain, a heart, etc. A deep understanding of this process will help researchers who aim to rebuild damaged or diseased organs for patients in need.

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Researchers programmed cells to self-assemble into complex structures such as this one with three differently colored layers. Credit: Wendell Lim/UCSF

A fascinating report published this week describes a system that allows researchers to program cells to self-organize into three-dimensional structures that mimic those seen during early development. The study applied a customizable, synthetic signaling molecule called synNotch developed in the Wendell Lim’s UCSF lab by co-author Kole Roybal, PhD, now an assistant professor of microbiology and immunology at UCSF, and Leonardo Morsut, PhD, now an assistant professor of stem cell biology and regenerative medicine at the University of Southern California.

A UCSF press release by Nick Weiler describes how synNotch was used:

“The researchers engineered cells to respond to specific signals from neighboring cells by producing Velcro-like adhesion molecules called cadherins as well as fluorescent marker proteins. Remarkably, just a few simple forms of collective cell communication were sufficient to cause ensembles of cells to change color and self-organize into multi-layered structures akin to simple organisms or developing tissues.”

Senior author Wendell Lim also explained how this system could overcome the challenges facing those aiming to build organs via 3D bioprinting technologies:

“People talk about 3D-printing organs, but that is really quite different from how biology builds tissues. Imagine if you had to build a human by meticulously placing every cell just where it needs to be and gluing it in place. It’s equally hard to imagine how you would print a complete organ, then make sure it was hooked up properly to the bloodstream and the rest of the body. The beauty of self-organizing systems is that they are autonomous and compactly encoded. You put in one or a few cells, and they grow and organize, taking care of the microscopic details themselves.”

Study was published in Science.

Can stem cells help people recover from a stroke? Join us for a Facebook Live event this Thursday, May 31 for the answers

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Stroke is one of the leading causes of death in the US and the leading cause of serious, long-term disability. But could stem cell therapies change that and help people who’ve had a brain attack?  Could stem cells help repair the damage caused by a stroke and restore a person’s ability to speak normally, to be able to walk without a limp or regain strength in their hands and arms?

To find out the answers to these and other questions joins us for “Ask the Expert”, a special Facebook Live event this Thursday, May 31, from noon till 1pm PDT

 The event will feature Dr. Gary Steinberg, the Chair of Neurosurgery at Stanford University. Dr. Steinberg is currently running a CIRM-funded clinical trial targeting stroke.

We will also be joined by CIRM Senior Science Officer Lila Collins, PhD who can talk about the broad range of other projects using stem cells to help people recover from a stroke.

We are also delighted to welcome Sonia Coontz, who suffered a devastating stroke several years ago and made a remarkable recovery after getting a stem cell therapy.

To join us for the event, all you have to do is go to our Facebook page on Thursday at noon (PDT) and you should see a video playing, which you can watch on mobile or desktop. Click the video to enter viewing mode.

Also, make sure to “like” our page before the event to receive a notification that we’ve gone live.

And we want to hear from you, so you will be able to post questions for the experts to answer or, you can email them directly to us at info@cirm.ca.gov

We look forward to seeing you there.

 

‘Ask The Expert’ on Facebook Live about the power of stem cells to reverse damage caused by a stroke.

facebook-live-brand-awarenessIt’s not often you get a chance to ask a world class stem cell expert a question about their work, and how it might help you or someone you love. But on Thursday, May 31 you can do just that.

CIRM is hosting a special ‘Ask the Expert’ event on Facebook Live. The topic is Strokes and Stem Cells. Just head over to our Facebook Page on May 31st from noon till 1pm PST to experience it live. You can also re-watch the event any time after the broadcast has ended from our Facebook videos page.

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We will be joined by Dr. Gary Steinberg, chair of neurosurgery at Stanford University, who will talk to us about his work in helping reverse the damage caused by a stroke, even for people who experienced a brain attack several years ago.

CIRM Senior Science Officer, Dr. Lila Collins, will talk about other stem cell research targeting stroke, its promise and some of the problems that still need to be overcome.

You will have a chance to ask questions of both our experts, either live on the day or by sending us questions in advance at info@cirm.ca.gov.

We’ll post reminders on Facebook so make sure to follow us. But for now, mark the date and time on your diary and please feel free to share this information with anyone you think might be interested.

It promises to be a fascinating event.

 

 

UC Davis researchers make stem cell-derived mini-brains that contain blood vessels

Growing neurons on a flat petri dish is a great way to study the inner workings of nerve signals in the brain. But I think it’s safe to argue that a two-dimensional lawn of cells doesn’t capture all the complexity of our intricate, cauliflower-shaped brains. Then again, cracking open the skulls of living patients is also not a viable path for fully understanding the molecular basis of brain disorders.

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Brain organoids (two white balls) growing in petri dish.
Image: Pasca Lab, Stanford University.

The recent emergence of stem cell-derived mini-brains, or brain organoids, as a research tool is bridging this impasse. With induced pluripotent stem cells (iPSCs) derived from a readily-accessible skin sample from patients, it’s possible to generate three-dimensional balls of cells that mimic particular parts of the brain’s anatomy. These mini-brains have the expected type of neurons, as well as other cells that support neuron function. We’ve written many blogs, most recently in January, on the applications of this cutting-edge tool.

With any new technology, there is always room for improvement. One thing that most mini-brains lack is their own system of blood vessels, or vasculature. That’s where Dr. Ben Waldau, a vascular neurosurgeon at UC Davis Medical Center, and his lab come into the picture. Last week, their published work in NeuroReport showed that incorporating blood vessels into a brain organoid is possible.

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A stained cross-section of a brain organoid showing that blood vessels (in red) have penetrated both the outer, more organized layers and the inner core. Image: UC Davis Institute for Regenerative Cures

Using iPSCs from one patient, the Waldau team separately generated brain organoids and blood vessels cells, also called endothelial cells. After growing each for about a month, the organoids were embedded in a gelatin containing the endothelial cells. In an excellent Wired article, writer Megan Molteni explains what happened next:

“After incubating for three weeks, they took a single organoid and transplanted it into a tiny cavity carefully carved into a mouse’s brain. Two weeks later the organoid was alive, well—and, critically, had grown capillaries that penetrated all the way to its inner layers.”

Every tissue relies on nutrients and oxygen from the blood. As Molteni suggests, being able to incorporate blood vessels and brain organoids from the same patient’s cells may make it possible to grow and study even more complex brain structures without the need of a mouse using fluidic pumps.

As Waldau explains in the Wired article, this vascularized brain organoid system also adds promise to the ultimate goal of repairing damaged brain tissue:

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Ben Waldau

“The whole idea with these organoids is to one day be able to develop a brain structure the patient has lost made with the patient’s own cells. We see the injuries still there on the CT scans, but there’s nothing we can do. So many of them are left behind with permanent neural deficits—paralysis, numbness, weakness—even after surgery and physical therapy.”

 

 

Stem Cell Stories That Caught our Eye: Stem Cell Therapies for Stroke and Duchenne Muscular Dystrophy Patients

With the Thanksgiving holiday behind us, we’re back to the grind at CIRM. Here are two exciting CIRM-funded stem cell stories that happened while you were away.

Stanford Scientists Are Treating Stroke Patients with Stem Cells

Smithsonian Magazine featured the work of a CIRM-funded scientist in their December Magazine issue. The article, “A Neurosurgeon’s Remarkable Plan to Treat Stroke Victims with Stem Cells”, features Dr. Gary Steinberg, who is the Chair of Neurosurgery at Stanford Medical Center and the founder of the Stanford Stroke Center.

Gary Steinberg (Photo by Jonathan Sprague)

The brain and its 100 billion cells need blood, which carries oxygen and nutrients, to function. When that blood supply is cut off, brain cells start to die and patients experience a stroke. Stroke can happen in one of two ways: either by blood clots that block the arteries and blood vessels that send blood to the brain or by blood vessels that burst within the brain itself. Symptoms experienced by stroke victims vary based on the severity of the stroke, but often patients report experiencing numbness or paralysis in their limbs or face, difficulty walking, talking and understanding.

Steinberg and his team at Stanford are developing a stem cell treatment to help stroke patients. Steinberg believes that not all brain cells die during a stroke, but rather some brain cells become “dormant” and stop functioning instead. By transplanting stem cells derived from donated bone marrow into the brains of stroke patients, Steinberg thinks he can wake up these dormant cells much like how the prince wakens Sleeping Beauty from her century of enchanted sleep.

Basically, the transplanted cells act like a defibrillator for the dormant cells in the stroke-damaged area of the brain. Steinberg thinks that the transplanted cells secrete proteins that signal dormant brain cells to wake up and start functioning normally again, and that they also trigger a “helpful immune response” that prompts the brain to repair itself.

Sonia has seen first hand how a stroke can rob you of even your most basic abilities.

Steinberg tested this stem cell treatment in a small clinical trial back in 2013. 18 patients were treated and many of them showed improvements in their symptoms. The Smithsonian piece mentions a particular patient who had a remarkable response to the treatment. Sonia Olea Coontz, at age 32, suffered a stroke that robbed her of most of her speech and her ability to use her right arm and leg. After receiving Steinberg’s stem cell treatment, Sonia rapidly improved and was able to raise her arm above her head and gained most of her speech back. You can read more about her experience in our Stories of Hope.

In collaboration with a company called SanBio, Steinberg’s team is now testing this stem cell therapy in 156 stroke patients in a CIRM-funded phase 2 clinical trial. The trial will help answer the question of whether this treatment is safe and also effective in a larger group of patients.

The Smithsonian article, which I highly recommend reading, shared Steinberg’s future aspirations to pursue stem cell therapies for traumatic brain and spinal cord injuries as well as neurodegenerative diseases like Alzheimer’s, Parkinson’s and ALS.

 

Capricor Approved to Launch New Clinical Trial for Duchenne Muscular Dystrophy

On Wednesday, Capricor Therapeutics achieved an exciting milestone for its leading candidate CAP-1002 – a stem cell-based therapy developed to treat boys and young men with a muscle-wasting disease called Duchenne muscular dystrophy (DMD).

The Los Angeles-based company announced that it received approval from the US Food and Drug Administration (FDA) for their investigational new drug (IND) application to launch a new clinical trial called HOPE II that’s testing repeated doses of CAP-1002 cells in DMD patients. The cells are derived from donated heart tissue and are believed to release regenerative factors that strengthen heart and other muscle function in DMD patients.

Capricor is currently conducting a Phase 2 trial, called HOPE-1, that’s testing a single dose of CAP-1002 cells in 24 DMD patients. CIRM is funding this trial and you can learn more about it on our clinical dashboard website and watch a video interview we did with a young man who participated in the trial.

Earlier this year, the company shared encouraging, positive results from the HOPE-1 trial suggesting that the therapy was improving some heart function and upper limb movement six months after treatment and was well-tolerated in patients. The goal of the new trial will be to determine whether giving patients repeated doses of the cell therapy over time will extend the benefits in upper limb movement in DMD patients.

In a news release, Capricor President and CEO Dr. Linda Marbán shared her company’s excitement for the launch of their new trial and what this treatment could mean for DMD patients,

Linda Marban, CEO of Capricor Therapeutics

“The FDA’s clearance of this IND upon its initial submission is a significant step forward in our development of CAP-1002. While there are many clinical initiatives in Duchenne muscular dystrophy, this is one of the very few to focus on non-ambulant patients. These boys and young men are looking to maintain what function they have in their arms and hands and, based on our previous study, we think CAP-1002 may be able to do exactly that.”

Curing the Incurable through Definitive Medicine

“Curing the Incurable”. That was the theme for the first annual Center for Definitive and Curative Medicine (CDCM) Symposium held last week at Stanford University, in Palo Alto, California.

The CDCM is a joint initiative amongst Stanford Healthcare, Stanford Children’s Health and the Stanford School of Medicine. Its mission is to foster an environment that accelerates the development and translation of cell and gene therapies into clinical trials.

The research symposium focused on “the exciting first-in-human cell and gene therapies currently under development at Stanford in bone marrow, skin, cardiac, neural, pancreatic and neoplastic diseases.” These talks were organized into four different sessions: cell therapies for neurological disorders, stem cell-derived tissue replacement therapies, genome-edited cell therapies and anti-cancer cell-based therapies.

A few of the symposium speakers are CIRM-funded grantees, and we’ll briefly touch on their talks below.

Targeting cancer

The keynote speaker was Irv Weissman, who talked about hematopoietic or blood-forming stem cells and their value as a cell therapy for patients with blood disorders and cancer. One of the projects he discussed is a molecule called CD47 that is found on the surface of cancer cells. He explained that CD47 appears on all types of cancer cells more abundantly than on normal cells and is a promising therapeutic target for cancer.

Irv Weissman

Irv Weissman

“CD47 is the first gene whose overexpression is common to all cancer. We know it’s molecular mechanism from which we can develop targeted therapies. This would be impossible without collaborations between clinicians and scientists.”

 

At the end of his talk, Weissman acknowledged the importance of CIRM’s funding for advancing an antibody therapeutic targeting CD47 into a clinical trial for solid cancer tumors. He said CIRM’s existence is essential because it “funds [stem cell-based] research through the [financial] valley of death.” He further explained that CIRM is the only funding entity that takes basic stem cell research all the way through the clinical pipeline into a therapy.

Improving bone marrow transplants

judith shizuru

Judith Shizuru

Next, we heard a talk from Judith Shizuru on ways to improve current bone-marrow transplantation techniques. She explained how this form of stem cell transplant is “the most powerful form of cell therapy out there, for cancers or deficiencies in blood formation.” Inducing immune system tolerance, improving organ transplant outcomes in patients, and treating autoimmune diseases are all applications of bone marrow transplants. But this technique also carries with it toxic and potentially deadly side effects, including weakening of the immune system and graft vs host disease.

Shizuru talked about her team’s goal of improving the engraftment, or survival and integration, of bone marrow stem cells after transplantation. They are using an antibody against a molecule called CD117 which sits on the surface of blood stem cells and acts as an elimination signal. By blocking CD117 with an antibody, they improved the engraftment of bone marrow stem cells in mice and also removed the need for chemotherapy treatment, which is used to kill off bone marrow stem cells in the host. Shizuru is now testing her antibody therapy in a CIRM-funded clinical trial in humans and mentioned that this therapy has the potential to treat a wide variety of diseases such as sickle cell anemia, leukemias, and multiple sclerosis.

Tackling stroke and heart disease

img_1327We also heard from two CIRM-funded professors working on cell-based therapies for stroke and heart disease. Gary Steinberg’s team is using human neural progenitor cells, which develop into cells of the brain and spinal cord, to treat patients who’ve suffered from stroke. A stroke cuts off the blood supply to the brain, causing the death of brain cells and consequently the loss of function of different parts of the body.  He showed emotional videos of stroke patients whose function and speech dramatically improved following the stem cell transplant. One of these patients was Sonia Olea, a young woman in her 30’s who lost the ability to use most of her right side following her stroke. You can read about her inspiring recover post stem cell transplant in our Stories of Hope.

Dr. Joe Wu. (Image Source: Sean Culligan/OZY)

Dr. Joe Wu. (Image Source: Sean Culligan/OZY)

Joe Wu followed with a talk on adult stem cell therapies for heart disease. His work, which is funded by a CIRM disease team grant, involves making heart cells called cardiomyocytes from human embryonic stem cells and transplanting these cells into patient with end stage heart failure to improve heart function. His team’s work has advanced to the point where Wu said they are planning to file for an investigational new drug (IND) application with the US Food and Drug Administration (FDA) in six months. This is the crucial next step before a treatment can be tested in clinical trials. Joe ended his talk by making an important statement about expectations on how long it will take before stem cell treatments are available to patients.

He said, “Time changes everything. It [stem cell research] takes time. There is a lot of promise for the future of stem cell therapy.”

Avalanches of exciting new stem cell research at the Keystone Symposia near Lake Tahoe

From January 8th to 13th, nearly 300 scientists and trainees from around the world ascended the mountains near Lake Tahoe to attend the joint Keystone Symposia on Neurogenesis and Stem Cells at the Resort at Squaw Creek. With record-high snowfall in the area (almost five feet!), attendees had to stay inside to stay warm and dry, and even when we lost power on the third day on the mountain there was no shortage of great science to keep us entertained.

Boy did it snow at the Keystone Conference in Tahoe!

Boy did it snow at the Keystone Conference in Tahoe!

One of the great sessions at the meeting was a workshop chaired by CIRM’s Senior Science Officer, Dr. Kent Fitzgerald, called, “Bridging and Understanding of Basic Science to Enable/Predict Clinical Outcome.” This workshop featured updates from the scientists in charge of three labs currently conducting clinical trials funded and supported by CIRM.

Regenerating injured connections in the spinal cord with neural stem cells

Mark Tuszynski, UCSD

Mark Tuszynski, UCSD

The first was a stunning talk by Dr. Mark from UCSD who is investigating how neural stem cells can help outcomes for those with spinal cord injury. The spinal cord contains nerves that connect your brain to the rest of your body so you can sense and move around in your environment, but in cases of severe injury, these connections are cut and the signal is lost. The most severe of these injuries is a complete transection, which is when all connections have been cut at a given spot, meaning no signal can pass through, just like how no cars could get through if a section of the Golden Gate Bridge was missing. His lab works in animal models of complete spinal cord transections since it is the most challenging to repair.

As Dr. Tuszynski put it, “the adult central nervous system does not spontaneously regenerate [after injury], which is surprising given that it does have its own set of stem cells present throughout.” Their approach to tackle this problem is to put in new stem cells with special growth factors and supportive components to let this process occur.

Just as most patients wouldn’t be able to come in for treatment right away after injury, they don’t start their tests until two weeks after the injury. After that, they inject neural stem cells from either the mouse, rat, or human spinal cord at the injury site and then wait a bit to see if any new connections form. Their group has shown very dramatic increases in both the number of new connections that regenerate from the injury site and extend much further than previous efforts have shown. These connections conduct electrochemical messages as normal neurons do, and over a year later they see no functional decline or tumors forming, which is often a concern when transplanting stem cells that normally like to divide a lot.

While very exciting, he cautions, “this research shows a major opportunity in neural repair that deserves proper study and the best clinical chance to succeed”. He says it requires thorough testing in multiple animal models before going into humans to avoid a case where “a clinical trial fails, not because the biology is wrong, but because the methods need tweaking.”

Everyone needs support – even dying cells

The second great talk was by Dr. Clive Svendsen of Cedars-Sinai Regenerative Medicine Institute on how stem cells might help provide healthy support cells to rescue dying neurons in the brains of patients with neurodegenerative diseases like Amyotrophic Lateral Sclerosis (ALS) and Parkinson’s. Some ALS cases are hereditary and would be candidates for a treatment using gene editing techniques. However, around 90 percent of ALS cases are “sporadic” meaning there is no known genetic cause. Dr. Svendsen explained how in these cases, a stem cell-based approach to at least fix the cellular cause of the disease, would be the best option.

While neurons often capture all the attention in the brain, since they are the cells that actually send messages that underlie our thoughts and behaviors, the Svendsen lab spends a great deal of time thinking about another type of cell that they think will be a powerhouse in the clinic: astrocytes. Astrocytes are often labeled as the support cells of the brain as they are crucial for maintaining a balance of chemicals to keep neurons healthy and functioning. So Dr. Svendsen reasoned that perhaps astrocytes might unlock a new route to treating neurodegenerative diseases where neurons are unhealthy and losing function.

ALS is a devastating disease that starts with early muscle twitches and leads to complete paralysis and death usually within four years, due to the rapid degeneration of motor neurons that are important for movement all over the body. Svendsen’s team found that by getting astrocytes to secrete a special growth factor, called “GDNF”, they could improve the survival of the neurons that normally die in their model of ALS by five to six times.

After testing this out in several animal models, the first FDA-approved trial to test whether astrocytes from fetal tissue can slow spinal motor neuron loss will begin next month! They will be injecting the precursor cells that can make these GDNF-releasing astrocytes into one leg of ALS patients. That way they can compare leg function and track whether the cells and GDNF are enough to slow the disease progression.

Dr. Svendsen shared with us how long it takes to create and test a treatment that is committed to safety and success for its patients. He says,

Clive Svendsen has been on a 15-year quest to develop an ALS therapy

Clive Svendsen 

“We filed in March 2016, submitted the improvements Oct 2016, and we’re starting our first patient in Feb 2017. [One document is over] 4500 pages… to go to the clinic is a lot of work. Without CIRM’s funding and support we wouldn’t have been able to do this. This isn’t easy. But it is doable!”

 

Improving outcomes in long-term stroke patients in unknown ways

Gary Steinberg

Gary Steinberg

The last speaker for the workshop, Dr. Gary Steinberg, a neurosurgeon at Stanford who is looking to change the lives of patients with severe limitations after having a stroke. The deficits seen after a stroke are thought to be caused by the death of neurons around the area where the stroke occurred, such that whatever functions they were involved with is now impaired. Outcomes can vary for stroke patients depending on how long it takes for them to get to the emergency department, and some people think that there might be a sweet spot for when to start rehabilitative treatments — too late and you might never see dramatic recovery.

But Dr. Steinberg has some evidence that might make those people change their mind. He thinks, “these circuits are not irreversibly damaged. We thought they were but they aren’t… we just need to continue figuring out how to resurrect them.”

He showed stunning videos from his Phase 1/2a clinical trial of several patients who had suffered from a stroke years before walking into his clinic. He tested patients before treatment and showed us videos of their difficulty to perform very basic movements like touching their nose or raising their legs. After carefully injecting into the brain some stem cells taken from donors and then modified to boost their ability to repair damage, he saw a dramatic recovery in some patients as quickly as one day later. A patient who couldn’t lift her leg was holding it up for five whole seconds. She could also touch her arm to her nose, whereas before all she could do was wiggle her thumb. One year later she is even walking, albeit slowly.

He shared another case of a 39 year-old patient who suffered a stroke didn’t want to get married because she felt she’d be embarrassed walking down the aisle, not to mention she couldn’t move her arm. After Dr. Steinberg’s trial, she was able to raise her arm above her head and walk more smoothly, and now, four years later, she is married and recently gave birth to a boy.

But while these studies are incredibly promising, especially for any stroke victims, Dr. Steinberg himself still is not sure exactly how this stem cell treatment works, and the dramatic improvements are not always consistent. He will be continuing his clinical trial to try to better understand what is going on in the injured and recovering brain so he can deliver better care to more patients in the future.

The road to safe and effective therapies using stem cells is long but promising

These were just three of many excellent presentations at the conference, and while these talks involved moving science into human patients for clinical trials, the work described truly stands on the shoulders of all the other research shared at conferences, both present and past. In fact, the reason why scientists gather at conferences is to give one another feedback and to learn from each other to better their own work.

Some of the other exciting talks that are surely laying down the framework for future clinical trials involved research on modeling mini-brains in a dish (so-called cerebral organoids). Researchers like Jürgen Knoblich at the Institute of Molecular Biotechnology in Austria talked about the new ways we can engineer these mini-brains to be more consistent and representative of the real brain. We also heard from really fundamental biology studies trying to understand how one type of cell becomes one vs. another type using the model organism C. elegans (a microscopic, transparent worm) by Dr. Oliver Hobert of Columbia University. Dr. Austin Smith, from the University of Cambridge in the UK, shared the latest about the biology of pluripotent cells that can make any cell type, and Stanford’s Dr. Marius Wernig, one of the meeting’s organizers, told us more of what he’s learned about the road to reprogramming an ordinary skin cell directly into a neuron.

Stay up to date with the latest research on stem cells by continuing to follow this blog and if you’re reading this because you’re considering a stem cell treatment, make sure you find out what’s possible and learn about what to ask by checking out closerlookatstemcells.org.


Samantha Yammine

Samantha Yammine

Samantha Yammine is a science communicator and a PhD candidate in Dr. Derek van der Kooy’s lab at the University of Toronto. You can learn more about Sam and her research on her website.

New approach could help turn back the clock and reverse damage for stroke patients

stroke

Stroke: courtesy WebMD

Stroke is the leading cause of serious, long-term disability in the US. Every year almost 800,000 people suffer from a stroke. The impact on their lives, and the lives of those around them can be devastating.

Right now the only treatment approved by the US Food and Drug Administration (FDA) is tissue plasminogen activator or tPA. This helps dissolve the blood clot causing most strokes and restores blood flow to the brain. However, to be fully effective this has to be administered within about 3-4 hours after the stroke. Many people are unable to get to the hospital in time and as a result suffer long-term damage, damage that for most people has been permanent.

But now a new study in Nature Medicine shows that might not be the case, and that this damage could even be reversible.

The research, done by a team at the University of Southern California (USC) uses a one-two punch combination of stem cells and a protein that helps those cells turn into neurons, the cells in the brain damaged by a stroke.

First, the researchers induced a stroke in mice and then transplanted human neural stem cells alongside the damaged brain tissue. They then added in a dose of the protein 3K3A-APC or a placebo.

hey found that mice treated with 3K3A-APC had 16 times more human stem-cell derived neurons than the mice treated with the placebo. Those neurons weren’t just sitting around doing nothing. USC’s Berislav Zlokovic, senior author of the paper, says they were actively repairing the stroke-induced damage.

“We showed that 3K3A-APC helps the grafted stem cells convert into neurons and make structural and functional connections with the host’s nervous system. No one in the stroke field has ever shown this, so I believe this is going to be the gold standard for future studies. Functional deficits after five weeks of stroke were minimized, and the mice were almost back to normal in terms of motor and sensorimotor functions. Synapses formed between transplanted cells and host cells, so there is functional activation and cooperation of transplanted cells in the host circuitry.”

The researchers wanted to make sure the transplanted cell-3K3A-ACP combination was really the cause of the improvement in the mice so they then used what’s called an “assassin toxin” to kill the neurons they had created. That reversed the improvements in the treated mice, leaving them comparable to the untreated mice. All this suggests the neurons had become an integral part of the mouse’s brain.

So how might this benefit people? You may remember that earlier this summer Stanford researchers produced a paper showing they had helped some 18 stroke patients, by injecting stem cells from donor bone marrow into their brain. The improvements were significant, including in at least one case regaining the ability to walk. We blogged about that work here

In that study, however, the cells did not become neurons nor did they seem to remain in the brain for an extended period. It’s hoped this new work can build on that by giving researchers an additional tool, the 3K3A-ACP protein, to help the transplanted cells convert to neurons and become integrated into the brain.

One of the other advantages of using this protein is that it has already been approved by the FDA for use in people who have experienced an ischemic stroke, which accounts for about 87 percent of all strokes.

The USC team now hope to get approval from the FDA to see if they can replicate their experiences in mice in people, through a Phase 2 clinical trial.