Treatments, cures and clinical trials: an in-person update on CIRM’s progress

Patients and Patient Advocates are at the heart of everything we do at CIRM. That’s why we are holding three free public events in the next few months focused on updating you on the stem cell research we are funding, and our plans for the future.

Right now we have 33 projects that we have funded in clinical trials. Those range from heart disease and stroke, to cancer, diabetes, ALS (Lou Gehrig’s disease), two different forms of vision loss, spinal cord injury and HIV/AIDS. We have also helped cure dozens of children battling deadly immune disorders. But as far as we are concerned we are only just getting started.

Over the course of the next few years, we have a goal of adding dozens more clinical trials to that list, and creating a pipeline of promising therapies for a wide range of diseases and disorders.

That’s why we are holding these free public events – something we try and do every year. We want to let you know what we are doing, what we are funding, how that research is progressing, and to get your thoughts on how we can improve, what else we can do to help meet the needs of the Patient Advocate community. Your voice is important in helping shape everything we do.

The first event is at the Gladstone Institutes in San Francisco on Wednesday, September 6th from noon till 1pm. The doors open at 11am for registration and a light lunch.

Gladstone Institutes

Here’s a link to an Eventbrite page that has all the information about the event, including how you can RSVP to let us know you are coming.

We are fortunate to be joined by two great scientists, and speakers – as well as being CIRM grantees-  from the Gladstone Institutes, Dr. Deepak Srivastava and Dr. Steve Finkbeiner.

Dr. Srivastava is working on regenerating heart muscle after it has been damaged. This research could not only help people recover from a heart attack, but the same principles might also enable us to regenerate other organs damaged by disease. Dr. Finkbeiner is a pioneer in diseases of the brain and has done ground breaking work in both Alzheimer’s and Huntington’s disease.

We have two other free public events coming up in October. The first is at UC Davis in Sacramento on October 10th (noon till 1pm) and the second at Cedars-Sinai in Los Angeles on October 30th (noon till 1pm). We will have more details on these events in the coming weeks.

We look forward to seeing you at one of these events and please feel free to share this information with anyone you think might be interested in attending.

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

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

Skin grafts fight diabetes and obesity.

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

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

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

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

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

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

How to reprogram your immune system (Kevin McCormack)

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

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

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

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

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

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

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

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

CIRM-funded spinal cord injury trial expands clinical sites

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

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

Ed Wirth

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

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

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

CIRM-funded stem cell clinical trial for spinal cord injury expands patient recruitment

asterias

It’s always great to start the week off with some good news. Today we learned that the Food and Drug Administration (FDA) has given Asterias Biotherapeutics approval to expand the number and type of people with spinal cord injuries that it treats in their CIRM-funded clinical trial.

Up till now, Asterias has been treating people who have injuries at the C5-C7 level, those are the lowest levels of the cervical spine, near the base of the neck. Now they will be able to treat people with injuries at the C4 level, that’s not only higher up the neck but it’s also the second most common form of spinal cord injury.

In a news release Dr. Ed Wirth, Asterias’ Chief Medical Officer, says this is a vote of confidence from the FDA in the company’s AST-OPC1 stem cell therapy:

“FDA’s decision to allow the company to enroll qualified patients with C-4 level injuries is the result of the data supporting the safety of both AST-OPC1 and the procedure to inject the cells and means that the second most common cervical spinal cord injury population can now be eligible to receive AST-OPC1. The overall changes to the study protocol will enhance our ability to enroll qualified patient candidates for our current SCiStar study and we also expect the changes to help enrollment rates in a future, larger clinical study.”

C4 image

Photo courtesy Shepherd Center, Atlanta

People who are injured at the C4 level are typically paralyzed from the neck down and need constant help, while people with C5-C7 injuries typically have some use of their hands and arms. Caring for someone with a C4 injury is expensive, with lifetime costs estimated around $5 million. Anything that could help people recover some movement would not only reduce those costs but would, more importantly, also increase the quality of life for people.

Asterias is not only expanding the patient population they are working with, they are also expanding the window for treating the injury. Currently patients have to be enrolled from 14 to 30 days post injury. In this new C4 group that window has been extended to 21 to 42 days post injury.

The reason for that change is that because C4 is higher up in the neck, newly injured people often need to be placed on a ventilator to help stabilize them. These patients take a little more time to recover from the initial trauma before they are ready to be treated.

We have blogged several times (here, here and here) about the encouraging news from the Asterias trial and how it appears to be helping people with injuries at the C5-C7 level recover some movement in their arms and hands. In some cases, such as with Kris Boesen for example, the improvement has been quite dramatic. Now the hope is that this new patient population will see similar benefits.

kris-boesen

Kris Boesen, CIRM spinal cord injury clinical trial patient.

The study is being conducted at six centers in the U.S., including some here in California,  and the company plans to increase this to up to 12 sites to accommodate the expanded patient enrollment.

Nine months in, stem cell-based therapy for spinal cord injury continues to improve paralyzed patients’ lives

If you’ve been following the Stem Cellar blog this year, then you must be as encouraged as we are with Asterias Biotherapeutics’ CIRM-funded clinical trial, which is testing an embryonic stem cell-based therapy for spinal cord injury.

astopc1Over many months, we’ve covered the company’s string of positive announcements that their cell therapy product – called AST-OPC1 – appears safe, is doing what is it’s supposed to after injection into the damaged spinal cord, and shows signs of restoring upper body function at 3 and 6 months after treatment. We’ve also written about first-hand accounts from some of the clinical trial participants who describe their remarkable recoveries.

That streak of good news continues today with Asterias’ early morning press release. The announcement summarizes 9-month results for a group of six patients who received an injection of 10 million AST-OPC1 cells 2 to 4 weeks after their injury (this particular trial is not testing the therapy on those with less recent injuries). In a nut shell, their improvements in arm, hand and finger movement seen at the earlier time points have persisted and even gotten better at 9 months.

Two motors levels = a higher quality of life
These participants sustained severe spinal cord injuries in the neck, leading to a loss of feeling and movement in their body from the neck down. To quantify the results of the cell therapy, researchers refer to “motor levels” of improvement. These levels correspond to an increasing number of motor, or movement, abilities. For a spinal cord injury victim paralyzed from the neck down, recovering two motor levels of function can mean the difference between needing 24-hour a day home care versus dressing, feeding and bathing themselves. The impact of this level of improvement cannot be overstated. As mentioned in the press release, regaining these abilities, “can result in lower healthcare costs, significant improvements in quality of life, increased ability to engage in activities of daily living, and increased independence.”

asterias9mo_results

9-month follow-up results of Asterias’ spinal cord injury trial. Patients treated with stem cell-based therapy (green line) have greater movement recovery compared to historical data from 62 untreated patients (Blue dotted line). Image: Asterias Biotherapeutics.

With the new 9-month follow-up data, the clinical researchers have confirmed that 3 out of the 6 (50%) patients show two motor levels of improvement. This result is up from 2 of 6 patients at the earlier time points. And all six patients have at least one motor level of improvement up through 9 months post-treatment. Now, make no mistake, spontaneous recovery from spinal cord injuries does occur. But historical data collected from 62 untreated patients show that only 29% reached two motor levels of improvement after 12-months.

As you can imagine, the Asterias team is optimistic about these latest results. Here’s what Chief Medical Officer, Dr. Edward Wirth had to say:

Edward-Wirth

Edward Wirth
Photo: Asterias

“The new efficacy results show that previously reported meaningful improvements in arm, hand and finger function in the 10 million cell cohort treated with AST-OPC1 cells have been maintained and in some patients have been further enhanced even 9 months following dosing. We are increasingly encouraged by these continued positive results, which are remarkable compared with spontaneous recovery rates observed in a closely matched untreated patient population.”

Equally encouraging is the therapy’s steady safety profile with no serious adverse events reported through the 9-month follow up.

Looking ahead
Dr. Jane Lebkowski, Asterias’ President of R&D and Chief Scientific Officer, will be presenting these data today during the International Society for Stem Cell Research (ISSCR) 2017 Annual Meeting held in Boston. Asterias expects to share more results later this fall after all six patients complete their 12-month follow-up visit.

The clinical trial is also treating another group of patients with a maximum dose of 20 million cells. The hope is that this cohort will show even more effectiveness.

For the sake of the more than 17,000 people who are incapacitated by a severe spinal cord injury each year, let’s hope the streak of good news continues.

Positively good news from Asterias for CIRM-funded stem cell clinical trial for spinal cord injury

AsteriasWhenever I give a talk on stem cells one of the questions I invariably get asked is “how do you know the cells are going where you want them to and doing what you want them to?”

The answer is pretty simple: you look. That’s what Asterias Biotherapeutics did in their clinical trial to treat people with spinal cord injuries. They used magnetic resonance imaging (MRI) scans to see what was happening at the injury site; and what they saw was very encouraging.

Asterias is transplanting what they call AST-OPC1 cells into patients who have suffered recent injuries that have left them paralyzed from the neck down.  AST-OPC1 are oligodendrocyte progenitor cells, which develop into cells that support and protect nerve cells in the central nervous system, the area damaged in spinal cord injury. It’s hoped the treatment will restore connections at the injury site, allowing patients to regain some movement and feeling.

Taking a closer look

Early results suggest the therapy is doing just that, and now follow-up studies, using MRIs, are adding weight to those findings.

The MRIs – taken six months after treatment – show that the five patients given a dose of 10 million AST-OPC1 cells had no evidence of lesion cavities in their spines. That’s important because often, after a spinal cord injury, the injury site expands and forms a cavity, caused by the death of nerve and support cells in the spine, that results in permanent loss of movement and function below the site, and additional neurological damage to the patient.

Another group of patients, treated in an earlier phase of the clinical trial, showed no signs of lesion cavities 12 months after their treatment.

Positively encouraging

In a news release, Dr. Edward Wirth, the Chief Medical Officer at Asterias, says this is very positive:

“These new follow-up results based on MRI scans are very encouraging, and strongly suggest that AST-OPC1 cells have engrafted in these patients post-implantation and have the potential to prevent lesion cavity formation, possibly reducing long-term spinal cord tissue deterioration after spinal cord injury.”

Because the safety data is also encouraging Asterias is now doubling the dose of cells that will be transplanted into patients to 20 million, in a separate arm of the trial. They are hopeful this dose will be even more effective in helping restore movement and function in patients.

We can’t wait to see what they find.

Scientists make stem cell-derived nerve cells damaged in spinal cord injury

The human spinal cord is an information highway that relays movement-related instructions from the brain to the rest of the body and sensory information from the body back to the brain. What keeps this highway flowing is a long tube of nerve cells and support cells bundled together within the spine.

When the spinal cord is injured, the nerve cells are damaged and can die – cutting off the flow of information to and from the brain. As a result, patients experience partial or complete paralysis and loss of sensation depending on the extent of their injury.

Unlike lizards which can grow back lost tails, the spinal cord cannot robustly regenerate damaged nerve cells and recreate lost connections. Because of this, scientists are looking to stem cells for potential solutions that can rebuild injured spines.

Making spinal nerve cells from stem cells

Yesterday, scientists from the Gladstone Institutes reported that they used human pluripotent stem cells to create a type of nerve cell that’s damaged in spinal cord injury. Their findings offer a new potential stem cell-based strategy for restoring movement in patients with spinal cord injury. The study was led by Gladstone Senior Investigator Dr. Todd McDevitt, a CIRM Research Leadership awardee, and was published in the journal Proceedings of the National Academy of Sciences.

The type of nerve cell they generated is called a spinal interneuron. These are specialized nerve cells in the spinal cord that act as middlemen – transporting signals between sensory neurons that connect to the brain to the movement-related, or motor, neurons that connect to muscles. Different types of interneurons exist in the brain and spinal cord, but the Gladstone team specifically created V2a interneurons, which are important for controlling movement.

V2a interneurons extend long distances in the spinal cord. Injuries to the spine can damage these important cells, severing the connection between the brain and the body. In a Gladstone news release, Todd McDevitt explained why his lab is particularly interested in making these cells to treat spinal cord injury.

Todd McDevitt, Gladstone Institutes

“Interneurons can reroute after spinal cord injuries, which makes them a promising therapeutic target. Our goal is to rewire the impaired circuitry by replacing damaged interneurons to create new pathways for signal transmission around the site of the injury.”

 

Transplanting nerve cells into the spines of mice

After creating V2a interneurons from human stem cells using a cocktail of chemicals in the lab, the team tested whether these interneurons could be successfully transplanted into the spinal cords of normal mice. Not only did the interneurons survive, they also set up shop by making connections with other nerve cells in the spinal cord. The mice that received the transplanted cells didn’t show differences in their movement suggesting that the transplanted cells don’t cause abnormalities in motor function.

Co-author on the paper, Dylan McCreedy, described how the transplanted stem cell-derived cells behaved like developing V2a interneurons in the spine.

“We were very encouraged to see that the transplanted cells sprouted long distances in both directions—a key characteristic of V2a interneurons—and that they started to connect with the relevant host neurons.”

Todd McDevitt (right), Jessica Butts (center) and Dylan McCreedy (left) created a special type of neuron from human stem cells that could potentially repair spinal cord injuries. (Photo: Chris Goodfellow, Gladstone)

A new clinical strategy?

Looking forward, the Gladstone team plans to test whether these V2a interneurons can improve movement in mice with spinal cord injury. If results look promising in mice, this strategy of transplanting V2a interneurons could be translated into human clinic trials although much more time and research are needed to get there.

Trials testing stem cell-based treatments for spinal cord injury are already ongoing. Many of them involve transplanting progenitor cells that develop into the different types of cells in the spine, including nerve and support cells. These progenitor cells are also thought to secrete important growth factors that help regenerate damaged tissue in the spine.

CIRM is funding one such clinical trial sponsored by Asterias Biotherapeutics. The company is transplanting oligodendrocyte progenitor cells (which make nerve support cells called oligodendrocytes) into patients with severe spinal cord injuries in their neck. The trial has reported encouraging preliminary results in all six patients that received a dose of 10 million cells. You can read more about this trial here.

What the Gladstone study offers is a different stem cell-based strategy for treating spinal cord injury – one that produces a specific type of spinal nerve cell that can reestablish important connections in the spinal cord essential for movement.

For more on this study, watch the Gladstone’s video abstract “Discovery Offers New Hope to Repair Spinal Cord.


Related Links:

Good news from Asterias’ CIRM-funded spinal cord injury trial

This week in the stem cell field, all eyes are on Asterias Biotherapeutics, a California-based company that’s testing a stem cell based-therapy in a CIRM-funded clinical trial for spinal cord injury patients. The company launched its Phase 1/2a clinical trial back in 2014 with the goal of determining the safety of the therapy and the optimal dose of AST-OPC1 cells to transplant into patients.

astopc1AST-OPC1 cells are oligodendrocyte progenitor cells derived from embryonic stem cells. These are cells located in the brain and spinal cord that develop into support cells that help nerve cells function and communicate with each other.

Asterias is transplanting AST-OPC1 cells into patients that have recently suffered from severe spinal cord injuries in their neck. This type of injury leaves patients paralyzed without any feeling from their neck down. By transplanting cells that can help the nerve cells at the injury site reform their connections, Asterias hopes that their treatment will allow patients to regain some form of movement and feeling.

And it seems that their hope is turning into reality. Yesterday, Asterias reported in a news release that five patients who received a dose of 10 million cells showed improvements in their ability to move after six months after their treatment. All five patients improved one level on the motor function scale, while one patient improved by two levels. A total of six patients received the 10 million cell dose, but so far only five of them have completed the six-month follow-up study, three of which have completed the nine-month follow-up study.

We’ve profiled two of these six patients previously on the Stem Cellar. Kris Boesen was the first patient treated with 10 million cells and has experienced the most improvement. He has regained the use of his hands and arms and can now feed himself and lift weights. Local high school student, Jake Javier, was the fifth patient in this part of the trial, and you can read about his story here.

Kris Boesen, CIRM spinal cord injury clinical trial patient.

Kris Boesen, CIRM spinal cord injury clinical trial patient.

jake_javier_stories_of_hope

Jake Javier and his Mom

The lead investigator on this trial, Dr. Richard Fessler, explained the remarkable progress that these patients have made since their treatment:

“With these patients, we are seeing what we believe are meaningful improvements in their ability to use their arms, hands and fingers at six months and nine months following AST-OPC1 administration. Recovery of upper extremity motor function is critically important to patients with complete cervical spinal cord injuries, since this can dramatically improve quality of life and their ability to live independently.”

Asterias will continue to monitor these patients for changes or improvements in movement and will give an update when these patients have passed the 12-month mark since their transplant. However, these encouraging preliminary results have prompted the company to look ahead towards advancing their treatment down the regulatory approval pathway, out of clinical trials and into patients.

Asterias CEO, Steve Cartt, commented,

Steve Cartt, CEO of Asterias Biotherapeutics

Steve Cartt, CEO of Asterias Biotherapeutics

“These results to date are quite encouraging, and we look forward to initiating discussions with the FDA in mid-2017 to begin to determine the most appropriate clinical and regulatory path forward for this innovative therapy.”

 

Talking with the US FDA will likely mean that Asterias will need to show further proof that their stem cell-based therapy actually improves movement in patients, rather than the patients spontaneously regaining movement (which has been observed in patients before). FierceBiotech made this point in a piece they published yesterday on this trial.

“Those discussions with FDA could lead to a more rigorous examination of the effect of AST-OPC1. Some patients with spinal injury experience spontaneous recovery. Asterias has put together matched historical data it claims show “a meaningful difference in the motor function recovery seen to date in patients treated with the 10 million cell dose of AST-OPC1.” But the jury will remain out until Asterias pushes ahead with plans to run a randomized controlled trial.”

In the meantime, Asterias is testing a higher dose of 20 million AST-OPC1 cells in a separate group of spinal cord injury patients. They believe this number is the optimal dose of cells for achieving the highest motor improvement in patients.

2017 will bring more results and hopefully more good news about Asterias’ clinical trial for spinal cord injury. And as always, we’ll keep you informed with any updates on our Stem Cellar Blog.

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.

First spinal cord injury trial patient gets maximum stem cell dose

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Kris Boesen, CIRM spinal cord injury clinical trial patient.

There comes a pivotal point in every experiment where you say “ok, now we are going to see if this really works.” We may be at that point in the clinical trial we are funding to see if stem cells can help people with spinal cord injuries.

Today Asterias Biotherapeutics announced they have given the first patient in the clinical trial the highest dose of 20 million cells. The therapy was administered at Santa Clara Valley Medical Center (SCVMC) in San Jose, California where Jake Javier – a young man who was treated at an earlier stage of the trial – was treated. You can read Jake’s story here.

The goal of the trial is to test the safety of transplanting three escalating doses of AST-OPC1 cells. These are a form of cell called oligodendrocyte progenitors, which are capable of becoming several different kinds of nerve cells, some of which play a supporting role and help protect nerve cells in the central nervous system – the area damaged in spinal cord injury.

In a news release, Dr. Edward Wirth, Asterias’ Chief Medical Officer, says this could be a crucial phase in the trial:

“We have been very encouraged by the early clinical efficacy and safety data for AST-OPC1, and we now look forward to evaluating the 20 million cell dose in complete cervical spinal cord injury patients. Based on extensive pre-clinical research, this is in the dosing range where we would expect to see optimal clinical improvement in these patients.”

To be eligible, individuals have to have experienced a severe neck injury in the last 30 days, one that has left them with no sensation or movement below the level of their injury, and that means they have typically lost all lower limb function and most hand and arm function.

In the first phase individuals were given 2 million cells. This was primarily to make sure that this approach was safe and wouldn’t cause any problems for the patients. The second phase boosted that dose to ten million cells. That was thought to be about half the therapeutic dose but it seemed to help all those enrolled. By 90 days after the transplant all five patients treated with ten million cells had shown some level of recovery of at least one motor level, meaning they had regained some use of their arms and/or hands on at least one side of their body. Two of the patients experienced an improvement of two motor levels. Perhaps the most impressive was Kris Boesen, who regained movement and strength in both his arms and hands. He says he is even experiencing some movement in his legs.

All this is, of course, tremendously encouraging, but we also have to sound a note of caution. Sometimes individuals experience spontaneous recovery after an accident like this. The fact that all five patients in the 10 million cell group did well suggests that this may be more than just a coincidence. That’s why this next group, the 20 million cell cohort, is so important.

As Steve McKenna, Chief of the Trauma Center at SCVMC, says; if we are truly going to see an improvement in people’s condition because of the stem cell transplant, this is when we would expect to see it:

“The early efficacy results presented in September from the 10 million cell AIS-A cohort were quite encouraging, and we’re looking forward to seeing if those meaningful functional improvements are maintained through six months and beyond. We are also looking forward to seeing the results in patients from the higher 20 million cell AST-OPC1 dose, as well as results in the first AIS-B patients.”

For more information about the Asterias clinical trial, including locations and eligibility requirements, go here: www.clinicaltrials.gov, using Identifier NCT02302157, and at the SCiStar Study Website (www.SCiStar-study.com).

We can never talk about this clinical trial without paying tribute to a tremendous patient advocate and a great champion of stem cell research, Roman Reed. He’s the driving force behind the Roman Reed Spinal Cord Injury Research Act  which helped fund the pioneering research of Dr. Hans Keirstead that laid the groundwork for this clinical trial.

 

 

Stem cell stories that caught our eye: healing diabetic ulcers, new spinal cord injury insights & an expanding CRISPR toolbox

Here are some stem cell stories that caught our eye this past week. Some are groundbreaking science, others are of personal interest to us, and still others are just fun.

Stem cells heal diabetic foot ulcers in pilot study
Foot ulcers are one of the many long-term complications that diabetics face. About 15 percent of patients develop these open sores which typically appear at the bottom of the foot. In a quarter of these cases, the ulcers lead to serious infection requiring amputation.

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Diabetic foot ulcers are open sores that don’t heal and in many cases leads to amputation. Image source: Izunpharma

But help may be on the horizon in the form of stem cells. Researchers at Mansoura University in Egypt recently presented results of a small study in which 10 patients with diabetic foot ulcers received standard care and another 10 patients received standard care plus injections of mesenchymal stem cells that had been collected from each patient’s own bone marrow. After just six weeks, the stem cell treated group showed a 50% reduction in the foot ulcers while the group with only standard care had a mere 7% reduction.

These superior results with the stem cells were observed even though the group receiving the stem cells had larger foot ulcers to begin with compared to the untreated patients. There are many examples of mesenchymal stem cells’ healing power which make them an extremely popular cell source for hundreds of on-going clinical trials. Mesenchymal stem cells are known to reduce inflammation and increase blood vessel formation, two properties that may be at work to give diabetic foot ulcers the chance to get better.

Medscape Medical News reported on these results which were presented at the 2016 annual meeting of the European Association for the Study of Diabetes (EASD) 2016 Annual Meeting

Suppressing nerve signals to help spinal cord injury victims
Losing the use of one’s limbs is a profound life-altering change for spinal cord injury victims. But their quality of life also suffers tremendously from the loss of bladder control and chronic pain sensations. So much so, victims often say that just improving these secondary symptoms would make a huge improvement in their lives.

While current stem cell-based clinical trials, like the CIRM-funded Asterias study, aim to reverse paralysis by restoring loss nerve signals, recent CIRM-funded animal data published in Cell Stem Cell from UC San Francisco suggest that nerve cells that naturally suppress nerve signals may be helpful for these other symptoms of spinal cord injury.

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Mature inhibitory neuron derived from human embryonic stem cells is shown after successfully migrated and integrated into the injured mouse spinal cord.
Photo by Jiadong Chen, UCSF

It turns out that the bladder control loss and chronic pain may be due to overactive nerve signals. So the lab of Arnold Kriegstein transplanted inhibitory nerve cells – derived from human embryonic stem cells – into mice with spinal cord injuries. The scientists observed that these human inhibitory nerve cells, or interneurons, successfully made working connections in the damaged mouse spinal cords. The rewiring introduced by these interneurons also led to reduced pain behaviors in the mice as well as improvements in bladder control.

 

 

In a Yahoo Finance interview, Kreigstein told reporters he’s eager to push forward with these intriguing results:

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Arnold Kriegstein, UCSF

“As a clinician, I’m very aware of the urgency that’s felt among patients who are often very desperate for treatment. As a result, we’re very interested in accelerating this work toward clinical trials as soon as possible, but there are many steps along the way. We have to demonstrate that this is safe, as well as replicating it in other animals. This involves scaling up the production of these human interneurons in a way that would be compatible with a clinical product.”

 

Expanding the CRISPR toolbox
If science had a fashion week, the relatively new gene editing technology called CRISPR/Cas9 would be sure to dominate the runway. You can think of CRISPR/Cas9 as a protein and RNA complex that acts as a molecular scissor which directly targets and cuts specific sequences of DNA in the human genome. Scientists are using CRISPR/Cas9 to develop innovative biomedical techniques such as removing disease-causing mutations in stem cells in hopes of developing potential treatments for patients suffering from diseases that have no cures.

What’s particularly interesting about the CRISPR/Cas9 system is that the Cas9 protein responsible for cutting DNA is part of a family of CRISPR associated proteins (Cas) that have similar but slightly different functions. Scientists are currently expanding the CRISPR toolbox by exploring the functions of other CRISPR associated proteins for gene editing applications.

A CIRM-funded team at UC Berkeley is particularly interested in a CRISPR protein called C2c2, which is different from Cas9 in that it targets and cuts RNA rather than DNA. Led by Berkeley professor Jennifer Doudna, the team discovered that the CRISPR/C2c2 complex has not just one, but two, distinct ways that it cuts RNA. Their findings were published this week in the journal Nature.

The first way involves creation: C2c2 helps make the guide RNAs that are used to find the RNA molecules that it wants to cut. The second way involves destruction: after the CRISPR/C2c2 complex finds it’s RNAs of choice, C2c2 can then cut and destroy the RNAs.

Doudna commented on the potential applications for this newly added CRISPR tool in a Berkeley News release:

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Jennifer Doudna: Photo courtesy of iPSCell.com

“This study expands our molecular understanding of C2c2 to guide RNA processing and provides the first application of this novel RNase. C2c2 is essentially a self-arming sentinel that attacks all RNAs upon detecting its target. This activity can be harnessed as an auto-amplifying detector that may be useful as a low-cost diagnostic.”