Stem cell therapy for Parkinson’s disease shows promise in monkeys

Tremors, muscle stiffness, shuffling, slow movement, loss of balance. These are all symptoms of Parkinson’s disease (PD), a neurodegenerative disorder that progressively destroys the dopamine-producing neurons in the brain that control movement.

While there is no cure for Parkinson’s disease, there are drugs like Levodopa and procedures like deep brain stimulation that alleviate or improve some Parkinsonian symptoms. What they don’t do, however, is slow or reverse disease progression.

Scientists are still trying to figure out what causes Parkinson’s patients to lose dopaminergic neurons, and when they do, they hope to stop the disease in its early stages before it can cause the debilitating symptoms mentioned above. In the meantime, some researchers see hope for treating Parkinson’s in the form of stem cell therapies that can replace the brain cells that are damaged or lost due to the disease.

Dopaminergic neurons derived from induced pluripotent stem cells. (Xianmin Zeng, Buck Institute)

Promising results in monkeys

This week, a team of Japanese scientists reported in the journal Nature that they treated monkeys with Parkinson’s-like symptoms by transplanting dopaminergic neurons made from human stem cells into their brains. To prevent the monkeys from rejecting the human cells, they were treated with immunosuppressive drugs. These transplanted neurons survived for more than two years without causing negative side effects, like tumor growth, and also improved PD symptoms, making it easier for the monkeys to move around.

The neurons were made from induced pluripotent stem cells (iPSCs), which are stem cells that can become any cell type in the body and are made by transforming mature human cells, like skin, back to an embryonic-like state. The scientists transplanted neurons made from the iPSCs of healthy people and PD patients into the monkeys and saw that both types of neurons survived and functioned properly by producing dopamine in the monkey brains.

Experts in the field spoke to the importance of these findings in an interview with Nature News. Anders Bjorklund, a neuroscientist at Lund University in Sweden, said “it’s addressing a set of critical issues that need to be investigated before one can, with confidence, move to using the cells in humans,” while Lorenz Studer, a stem-cell scientist at the Memorial Sloan Kettering Cancer Center in New York City, said that “there are still issues to work out, such as the number of cells needed in each transplant procedure. But the latest study is ‘a sign that we are ready to move forward.’”

Next stop, human trials

Jun Takahashi

Looking ahead, Jun Takahashi, the senior author on the study, explained that his team hopes to launch a clinical trial testing this iPSC-based therapy by the end of 2018. Instead of developing personalized iPSC therapies for individual PD patients, which can be time consuming and costly, Takahashi plans to make special donor iPSC lines (called human leukocyte antigen or HLA-homozygous iPSCs) that are immunologically compatible with a larger population of patients.

In a separate study published at the same time in Nature Communications, Takahashi and colleagues showed that transplanting neurons derived from immune-matched monkey iPSCs improved their survival and dampened the immune response.

The Nature News article does a great job highlighting the findings and significance of both studies and also mentions other research projects using stem cells to treat PD in clinical trials.

“Earlier this year, Chinese researchers began a Parkinson’s trial that used a different approach: giving patients neural-precursor cells made from embryonic stem cells, which are intended to develop into mature dopamine-producing neurons. A year earlier, in a separate trial, patients in Australia received similar cells. But some researchers have expressed concerns that the immature transplanted cells could develop tumour-causing mutations.

Meanwhile, researchers who are part of a Parkinson’s stem-cell therapy consortium called GForce-PD, of which Takahashi’s team is a member, are set to bring still other approaches to the clinic. Teams in the United States, Sweden and the United Kingdom are all planning trials to transplant dopamine-producing neurons made from embryonic stem cells into humans. Previously established lines of embryonic stem cells have the benefit that they are well studied and can be grown in large quantities, and so all trial participants can receive a standardized treatment.”

You can read more coverage on these research studies in STATnews, The San Diego Union Tribune, and Scientific American.

For a list of projects CIRM is funding on Parkinson’s disease, visit our website.

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Stem cell treatment helps puppies born with spina bifida walk again

Just when you thought puppies couldn’t get any cuter, this video appears in your twitter feed.

These adorable English bulldog puppies are named Darla and Spanky, and they were born with a birth defect called spina bifida where the bones and tissue surrounding the spinal cord fail to fuse completely. Spina bifida occurs in 1500-2000 children in the US each year and can cause serious problems such as paralysis and issues with walking, cognition, and bladder or bowel control. Dogs born with this condition usually cannot use their hind legs, and as a sad consequence, are typically put down at a young age.

Cutting edge research from UC Davis is now giving these unfortunate puppies hope. Diana Farmer, a fetal surgeon at UC Davis Health, and scientists from the university’s Veterinary Institute for Regenerative Cures have developed a combination surgery and stem cell transplant, using placenta-derived mesenchymal stromal cells (PMSCs), to treat puppies with spina bifida. Because prenatal screening for spina bifida is not done in dogs, Darla and Spanky received the treatment when they were ten weeks old.

With funding from a CIRM preclinical development award, Farmer has done similar surgeries in lambs that are still in the womb. A UC Davis news release provided historical background on Farmer’s work on spina bifida,

“Farmer pioneered the use of surgery prior to birth to improve brain development in children with spina bifida. She later showed that prenatal surgery combined with human placenta-derived mesenchymal stromal cells (PMSCs), held in place with a cellular scaffold, helped research lambs born with the disorder walk without noticeable disability.”

As you can see from the video, the surgeries were a success. Darla and Spanky are now able to live up to their full puppy potential and will live happily ever after with their adoptive family in New Mexico.

Looking forward, Farmer and her team would like to treat more dogs with spina bifida so they can improve another negative consequence of spina bifida called incontinence, or an uncontrollable bladder. The UC Davis release explained that, “while Darla and Spanky are very mobile and doing well on their feet, they still require diapers.” (Side note: this video proves that puppies can make anything look cute, even dirty diapers.)

Additionally, the team is hoping to receive regulatory approval from the US Food and Drug Administration to launch a clinical trial testing this therapy in humans. If this stem cell treatment proves to be both safe and effective in clinical trials, it could potentially prevent spina bifida from ever happening in animals and in humans.

English Bulldog undergoing spina bifida surgery at UC Davis Veterinary Medical Teaching Hospital. (Gregory Urquiaga/UC Davis)

Stories that caught our eye: stem cell transplants help put MS in remission; unlocking the cause of autism; and a day to discover what stem cells are all about

multiple-sclerosis

Motor neurons

Stem cell transplants help put MS in remission: A combination of high dose immunosuppressive therapy and transplant of a person’s own blood stem cells seems to be a powerful tool in helping people with relapsing-remitting multiple sclerosis (RRMS) go into sustained remission.

Multiple sclerosis (MS) is an autoimmune disorder where the body’s own immune system attacks the brain and spinal cord, causing a wide variety of symptoms including overwhelming fatigue, blurred vision and mobility problems. RRMS is the most common form of MS, affecting up to 85 percent of people, and is characterized by attacks followed by periods of remission.

The HALT-MS trial, which was sponsored by the National Institute of Allergy and Infectious Diseases (NIAID), took the patient’s own blood stem cells, gave the individual chemotherapy to deplete their immune system, then returned the blood stem cells to the patient. The stem cells created a new blood supply and seemed to help repair the immune system.

Five years after the treatment, most of the patients were still in remission, despite not taking any medications for MS. Some people even recovered some mobility or other capabilities that they had lost due to the disease.

In a news release, Dr. Anthony Fauci, Director of NIAID, said anything that holds the disease at bay and helps people avoid taking medications is important:

“These extended findings suggest that one-time treatment with HDIT/HCT may be substantially more effective than long-term treatment with the best available medications for people with a certain type of MS. These encouraging results support the development of a large, randomized trial to directly compare HDIT/HCT to standard of care for this often-debilitating disease.”

scripps-campus

Scripps Research Institute

Using stem cells to model brain development disorders. (Karen Ring) CIRM-funded scientists from the Scripps Research Institute are interested in understanding how the brain develops and what goes wrong to cause intellectual disabilities like Fragile X syndrome, a genetic disease that is a common cause of autism spectrum disorder.

Because studying developmental disorders in humans is very difficult, the Scripps team turned to stem cell models for answers. This week, in the journal Brain, they published a breakthrough in our understanding of the early stages of brain development. They took induced pluripotent stem cells (iPSCs), made from cells from Fragile X syndrome patients, and turned these cells into brain cells called neurons in a cell culture dish.

They noticed an obvious difference between Fragile X patient iPSCs and healthy iPSCs: the patient stem cells took longer to develop into neurons, a result that suggests a similar delay in fetal brain development. The neurons from Fragile X patients also had difficulty forming synaptic connections, which are bridges that allow for information to pass from one neuron to another.

Scripps Research professor Jeanne Loring said that their findings could help to identify new drug therapies to treat Fragile X syndrome. She explained in a press release;

“We’re the first to see that these changes happen very early in brain development. This may be the only way we’ll be able to identify possible drug treatments to minimize the effects of the disorder.”

Looking ahead, Loring and her team will apply their stem cell model to other developmental diseases. She said, “Now we have the tools to ask the questions to advance people’s health.”

A Day to Discover What Stem Cells Are All about.  (Karen Ring) Everyone is familiar with the word stem cells, but do they really know what these cells are and what they are capable of? Scientists are finding creative ways to educate the public and students about the power of stem cells and stem cell research. A great example is the University of Southern California (USC), which is hosting a Stem Cell Day of Discovery to educate middle and high school students and their families about stem cell research.

The event is this Saturday at the USC Health Sciences Campus and will feature science talks, lab tours, hands-on experiments, stem cell lab video games, and a resource fair. It’s a wonderful opportunity for families to engage in science and also to expose young students to science in a fun and engaging way.

Interest in Stem Cell Day has been so high that the event has already sold out. But don’t worry, there will be another stem cell day next year. And for those of you who don’t live in Southern California, mark your calendars for the 2017 Stem Cell Awareness Day on Wednesday, October 11th. There will be stem cell education events all over California and in other parts of the country during that week in honor of this important day.

 

 

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.

CIRM-funded stem cell trial for retinitis pigmentosa makes progress

A CIRM-funded clinical trial for retinitis pigmentosa (RP), a degenerative eye disease that causes blindness, recently reached its next milestone and announced the completion of its patient enrollment for a phase I/IIa study testing a stem cell derived therapy. This is a major step forward in determining whether this approach is both safe and effective at improving sight in RP patients.

retinitis pigmentosas_1RP is a genetically inherited disease that destroys the light-sensing photoreceptor cells at the back of the eye. Symptoms of the disease typically appear in childhood and often cause blindness by the age of 40. RP affects approximately 100,000 people in the US, and there are no effective treatments.

Stem cell treatment for RP

Regenerative medicine offers a promising strategy for treating RP by replacing the lost or damaged photoreceptors in the retina with healthy retinal cells derived from human stem cells.

CIRM is funding a clinical trial that’s testing a stem cell-based treatment for advanced RP. The trial is sponsored by a California-based company called jCyte, which was founded in 2012 by Dr. Henry Klassen and Dr. Jing Yang, both currently professors at UC Irvine.

The treatment involves injecting human retinal progenitor cells, which are derived from adult stem cells, into the damaged area of the retina at the back of the eye to hopefully improve vision. These progenitor cells could either replace the damaged photoreceptors in the eye, or could help rescue the remaining photoreceptors from being destroyed.

RP clinical trials makes progress

Earlier this year, jCyte reported that they had treated the first nine patients in their phase I/IIa safety trial and did not observe any negative side effects caused by the treatment. Today, they announced that they have finished the trial enrollment with a total of 28 patients. Four different doses of retinal progenitor cells were tested in this patient group to determine both safety and the optimal dose of cells. While the results of this trial won’t be available until next year, eight of the enrolled patients have already completed the one-year study and have shown promising safety results.

In a jCyte news release, Dr. Klassen explained:

Klassen“We have successfully completed four DSMB (Data Safety Monitoring Board) reviews. So far, trial participants have had no significant side effects, with good tolerance of the injected cells. We are quite gratified by the results.”

CIRM is also happy to hear these positive findings as proving that a stem cell treatment is safe in patients is essential for moving a clinical trial forward. Jonathan Thomas, Chairman of the CIRM Governing Board commented in a CIRM news release:

Jonathan Thomas

Jonathan Thomas

“We are really encouraged by the preliminary safety results of the jCyte trial. RP is a rare disease and an unmet medical need that could benefit from advances in stem cell-based treatments. The jCyte trial will hopefully pave the way for determining how stem cells can improve vision in RP patients, and ultimately other diseases of blindness.”

Next steps

As this trial moves forward, jCyte hopes to begin planning a phase IIb trial that will determine whether their stem cell-based therapy is effective at improving vision in advanced RP patients.

“I look forward to the next stage of development towards commercialization,” said jCyte CEO Paul Bresge. “We never lose sight of our singular goal: to ultimately deliver this much-needed therapy to patients.”

If all goes well, additional RP patients will be needed to participate in the second phase of the jCyte trial. Patients who are interested in learning more about this trial or enrolling in future trials, should visit the jCyte website.

If you want to learn more about how stem cells could potentially yield new treatments for diseases of blindness, watch our video “Eyeing Stem Cell Therapies for Vision Loss”.


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Throwback Thursday: Progress to a Cure for Type 1 Diabetes

Welcome back to our “Throwback Thursday” series on the Stem Cellar. Over the years, we’ve accumulated an arsenal of valuable stem cell stories on our blog. Some of these stories represent crucial advances towards stem cell-based cures for serious diseases and deserve a second look.

novemberawarenessmonthThis week in honor of Diabetes Awareness Month, we are featuring type 1 diabetes (T1D), a chronic disease that destroys the insulin-producing beta cells in your pancreas. Without these important cells, patients cannot maintain the proper levels of glucose, a fancy name for sugar, in their blood and are at risk for many complications including heart disease, blindness, and even death.

Cell replacement therapy is evolving into an attractive option for patients with T1D. Replacing lost beta cells in the pancreas is a more permanent and less burdensome solution than the daily insulin shots (or insulin pumps) that many T1D patients currently take.

So let’s take a look at the past year’s advances in stem cell research for diabetes.

Making Insulin-Producing Cells from Stem Cells and Skin

This year, there were a lot of exciting studies that improved upon previous methods for generating pancreatic beta cells in a dish. Here’s a brief recap of a few of the studies we covered on our blog:

  • Make pancreatic cells from stem cells. Scientists from the Washington University School of Medicine in St. Louis and the Harvard Stem Cell Institute developed a method that makes beta cells from T1D patient-derived induced pluripotent stem cells (iPSCs) that behave very similarly to true beta cells both in a dish and when transplanted into diabetic mice. Their discovery has the potential to offer personalized stem cell treatments for patients with T1D in the near future and the authors of the study predicted that their technology could be ready to test in humans in the next three to five years.
  • Making functional pancreatic cells from skin. Scientists from the Gladstone Institutes used a technique called direct reprogramming to turn human skin cells directly into pancreatic beta cells without having to go all the way back to a pluripotent stem cell state. The pancreatic cells looked and acted like the real thing in a dish (they were able to secrete insulin when exposed to glucose), and they functioned normally when transplanted into diabetic mice. This study is exciting because it offers a new and more efficient method to make functioning human beta cells in mass quantities.

    Functioning human pancreatic cells after they’ve been transplanted into a mouse. (Image: Saiyong Zhu, Gladstone)

    Functioning human pancreatic cells after they’ve been transplanted into a mouse. (Image: Saiyong Zhu, Gladstone)

  • Challenges of stem cell-derived diabetes treatments. At this year’s Ogawa-Yamanaka Stem Cell Award ceremony Douglas Melton, a well-renowned diabetes researcher from Harvard, spoke about the main challenges for developing stem cell-derived diabetes treatments. The first is the need for better control over the methods that make beta cells from stem cells. The second was finding ways to make large quantities of beta cells for human transplantation. The last was finding ways to prevent a patient’s immune system from rejecting transplanted beta cells. Melton and other scientists are already working on improving techniques to make more beta cells from stem cells. As for preventing transplanted beta cells from being attacked by the patient’s immune system, Melton described two possibilities: using an encapsulation device or biological protection to mask the transplanted cells from an attack.

Progress to a Cure: Clinical Trials for Type 1 Diabetes

Speaking of encapsulation devices, CIRM is funding a Phase I clinical trial sponsored by a San Diego-based company called ViaCyte that’s hoping to develop a stem cell-based cure for patients with T1D. The treatment involves placing a small encapsulated device containing stem cell-derived pancreatic precursor cells under the skin of T1D patients. Once implanted, these precursor cells should develop into pancreatic beta cells that can secrete insulin into the patient’s blood stream. The goal of this trial is first to make sure the treatment is safe for patients and second to see if it’s effective in improving a patient’s ability to regulate their blood sugar levels.

To learn more about this exciting clinical trial, watch this fun video made by Youreka Science.

ViaCyte is still waiting on results for their Phase 1 clinical trial, but in the meantime, they are developing a modified version of their original device for T1D called PEC-Direct. This device also contains pancreatic precursor cells but it’s been designed in a way that allows the patient’s blood vessels to make direct connections to the cells inside the device. This vascularization process hopefully will improve the survival and function of the insulin producing beta cells inside the device. This study, which is in the last stage of research before clinical trials, is also being funded by CIRM, and we are excited to hear news about its progress next year.

ViaCyte's PEC-Direct device allows a patient's blood vessels to integrate and make contact with the transplanted beta cells.

ViaCyte’s PEC-Direct device allows a patient’s blood vessels to integrate and make contact with the transplanted beta cells.


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Deleting a single gene can boost blood stem cell regeneration

A serious side effect that cancer patients undergoing chemotherapy experience is myelosuppression. That’s a big word for a process that involves the decreased production of the body’s immune cells from hematopoietic stem cells (HSCs) or blood stem cells in the bone marrow. Without these important cells that make up the immune system, patients are at risk for major infections and even death.

Human blood (red) and immune cells (green) are made from hematopoietic/blood stem cells. Photo credit: ZEISS Microscopy.

Human blood (red) and immune cells (green) are made from hematopoietic/blood stem cells. Photo credit: ZEISS Microscopy.

Scientists are trying to find ways to treat cancer patients that have undergone myelosuppressive therapies, as well as patients that need bone marrow transplants to replace their own bone marrow that’s been damaged or removed. One possible solution is boosting the regenerative capacity of HSCs. Transplanting HSCs that are specially primed to reproduce rapidly into cells of the immune system could improve the outcome of bone marrow transplants in patients.

Deleting Grb10 boost blood stem cell regeneration

A CIRM-funded team from the UCLA Broad Stem Cell Research Center and the Jonsson Comprehensive Cancer Center has identified a single gene that can be manipulated to boost HSC regeneration in mice. The study, which was published in Cell Reports, found that deleting or turning off expression of an imprinted gene called Grb10 in HSCs caused these blood stem cells to reproduce more robustly after being transplanted into mice that had their bone marrow removed.

I just used another big word in that last paragraph, so let me explain. An imprinted gene is a gene that is expressed or activated based on which parent it was inherited from. Typically, you receive one copy of a gene from your mother and one from your father and both are expressed – a process called Mendelian inheritance. But imprinted genes are different – they are marked with specific epigenetic tags that silence their expression in the sperm or egg cells of the parents. Thus if you inherited an imprinted gene from your mother, the other copy of that gene from your father would be expressed and vice versa.

Scientists have discovered that imprinted genes are important for human development and also for directing what cell types adult stem cells like HSCs develop into. The team from UCLA led by senior author Dr. John Chute, was interested in answering a different question: are imprinted genes involved in determining the function of HSCs? They compared two different populations of HSCs derived from mouse bone marrow: a normal, healthy population and HSCs exposed to total body irradiation (TBI), which destroys the immune system. They discovered that the expression of an imprinted gene called Grb10 was dramatically higher in HSCs exposed to TBI compared to healthy HSCs.

Cell Reports

Deleting Grb10  increases blood stem cell regeneration in the bone marrow of irradiated mice (bottom) compared to normal mice (top). Cell Reports

Because Grb10 is an imprinted gene, the scientists deleted either the paternal or maternal copy of that gene in mice. While deleting the paternal Grb10 gene had no effect on the function of HSCs, maternal deletion dramatically boosted the capacity of HSCs to divide and make more copies of themselves. Without the maternal copy of Grb10, HSCs were able to regenerate at a much faster scale than normal HSCs.

To further prove their point, the team transplanted normal HSCs and HSCs that lacked Grb10 into TBI or fully irradiated mice. HSCs that lacked Grb10 were able to regenerate themselves and produce other immune cells more robustly 20 weeks after transplantation compared to normal HSCs.

Potential applications and future studies

This study offers two important findings. First, they discovered that Grb10 plays an important role “in regulating HSC self-renewal following transplantation and HSC regeneration in response to injury.” Second, they found that inhibiting Grb10 function in HSCs could have potential therapeutic applications for boosting “hematopoietic regeneration in the setting of HSC transplantation or following myelosuppressive injury.” Patients in need of bone marrow transplants could potentially receive more benefit from transplants of HSCs that don’t express the Grb10 gene.

In my opinion, further studies should be done to further understand the role of Grb10 in regulating HSC self-renewal and regeneration. What is the benefit of having this gene expressed in HSCs if inhibiting its expression leads to an increased regenerative capacity? Is it to prevent cancer from forming? Additionally, the authors will need to address the potential long-term side effects of inhibiting Grb10 expression in HSCs. They did report that mice that lacked the Grb10 gene did not develop blood cancers at one year of age which is good news. They also suggested that instead of deleting Grb10, new drugs could be identified that inhibit Grb10 function in HSCs.

A patient perspective on how stem cells could give a second vision to the blind

October is Blindness Awareness month. In honor of the patients who suffer from diseases of blindness and of the scientists and doctors who work tirelessly to develop treatments and cures for these diseases, we are featuring an interview with Kristin Macdonald, a woman who is challenged by Retinitis Pigmentosa (RP).

RP is a genetically inherited disease that affects the photoreceptors at the back of the eye in an area called the retina. It’s a hard disease to diagnose because the first signs are subtle. Patients slowly lose their peripheral vision and ability to see well at night. As the disease progresses, the window of sight narrows and patients experience “tunnel vision”. Eventually, they become totally blind. Currently, there is no treatment for RP, but stem cell research might offer a glimmer of hope.

Kristin MacDonald

Kristin MacDonald

Kristin Macdonald was the first patient treated in a CIRM-funded stem cell trial for RP run by Dr. Henry Klassen at UC Irvine. She is a patient advocate and inspirational speaker for the blind and visually impaired, and is also a patient ambassador for Americans for Cures. Kristin is an amazing woman who hasn’t let RP prevent her from living her life. It was my pleasure to interview her to learn more about her life’s vision, her experience in CIRM’s RP trial, and her thoughts on patient advocacy and the importance of stem cell research.


Q: Tell us about your experience with being diagnosed with RP?

I was officially diagnosed with RP at 31. RP is a very difficult thing to diagnose, and I had to go through a series of doctors before we figured it out. The signs were there in my mid-to-late twenties, but unfortunately I didn’t really know what they were.

Being diagnosed with RP was really surprising to me. I grew up riding horses and doing everything. I had 20/20 vision and didn’t need any reading glasses. I started getting these night vision symptoms in my mid-to-late 20s in New York when I was in Manhattan. It was then that I started tripping, falling and getting clumsy. But I didn’t know what was happening and I was having such a great time with my life that I just denied it. I didn’t want to acknowledge that anything was wrong.

So I moved out to Los Angeles to pursue an acting and television career, and I just kept ignoring that thing in the brain that says “something’s wrong”. By the time I broke my arm for the second time, I had to go to see a doctor. And that’s when they diagnosed me.

Q: How did you boost yourself back up after being diagnosed with RP?

RP doesn’t come with an instruction booklet. It’s a very gradual adjustment emotionally, physically and spiritually. The first thing I did was to get out of denial, which was a really scary place to be because you can break your leg that way. You have to acknowledge what’s happening in life otherwise you’ll never get anywhere or past anything. That was my first stage of getting over denial. As I slowly started to accept things, I learned to live in the moment, which in a way is a big thing in life because we should all be living for today.

I think the fear of someone telling you that you’re going to go into the dark when you’ve always lived your life in the light can be overwhelming at times. I used to go to the mall and sometimes a door to a store would be gone or an elevator that I used to see is gone. What I did to deal with these fears and changes was to become as proactive as possible. I enlisted all of the best people around me in the business. I started doing charitable work for the Center for the Partially Sighted and for the Foundation for Fighting Blindness. I sat on the board of AIRSLA.org, an internet radio service for the blind and visually impaired, where I still do my radio show. Through that, I met other people who were going through the same type of thing and would come into my home to teach me independent living skills.

I remember the first day when an independent living counselor from the Center for the Partially Sighted came to my house and said we have to check in and see what your adjustment to blindness is like. Those words cut through me. “Adjustment to blindness”. It felt like I was going to prison, that’s how it felt like to me back then. But I am so glad I reached out to the Center for the Partially Sighted because they gave me invaluable instructions on how to function as a blind person. They helped me realize I could really live a good life and be whole, and that blindness would never define me.

I also worked a lot on my spiritual side. I read a lot of positive thinking books and found comfort in my faith in god and the support from my family, friends and my boyfriend. I can’t even enumerate how good they’ve been to me.

Q: How has being blind impacted your ability to do the things you love?

I’m a very social person, so giving up my car and suddenly being confined at night was crushing to me. And we didn’t have Uber back then! During that time, I had to learn how to lead a full life socially. I still love to do salsa dancing but it’s tricky. If I stand on the sidelines, some of the dancers will pass you by because they don’t know you’re blind. I also learned how to horseback ride and swim in the ocean – just a different way. I go in the water on a surf leash. Or I ride around the ring with my best friend guiding me.

Kristin loves to ride horses.

Kristin doesn’t let being mostly blind stop her from riding horses.

Q: What treatments have you had for RP?

I investigated just about everything that was out there. [Laughs] After I was diagnosed, I became very proactive to find treatments. But after a while, I became discouraged because these treatments either didn’t work or still needed time for the FDA to give approval.

I did participate in a study nine years ago and had genetically modified cells put into my eye. I had two surgeries: one to put the cells in and one to take them out because the treatment hadn’t done anything. I didn’t get any improvement, and that was crushing to me because I had hoped and waited so long.

I just kept praying, waiting, reading and hoping. And then boom, all the sudden I got a phone call from UC Irvine saying they wanted me to participate in their stem cell trial for RP. They said I’d be the third person in the world to have it done and the first in their clinical trial. They told me I was to be the first North American patient to have progenitor cells put in my eye, which is pretty amazing.

Q: Was it easy to decide to participate in the UC Irvine CIRM-funded trial?

Yes. But don’t get me wrong, I’m human. I was a little scared. It’s a new thing and you have to sign papers saying that you understand that we don’t exactly know what the results will be. Essentially, you are agreeing to be a pathfinder.

Luckily, I have not had any adverse effects since the trial. But I’ve always had a great deal of faith in stem cells. For years, I’ve been hearing about it and I’ve always put my hopes in stem cells thinking that that’s going to be the answer for blindness.

Q: Have you seen any improvements in your sight since participating in this trial?

I was treated a year ago in June. The stem cell transplant was in my left eye, my worse eye that has never gotten better. It’s been about 15 months now, and I started to see improvement after about two months following the treatment. When I would go into my bathroom, I noticed that it was a lot brighter. I didn’t know if I was imagining things, but I called a friend and said, “I don’t know if I’m imagining things but I’m getting more light perception in this eye.”

Sure enough, over a period of about eight months, I had gradual improvement in light perception. Then I leveled off, but now there is no question that I’m photo sensitive. When I go out, I use my sunglasses, and I see a whole lot more light.

Because I was one of the first patients in the trial, they had to give me a small dose of cells to test for safety. So it was amazing that a smaller dose of cells was still able to help me gain back some sight! One of the improvements that I’ve had is that I can actually see the image of my finger waving back and forth on my left side, which I couldn’t before when I put mascara on. I say this because I have put lip pencil all over my mouth by accident. That must have been a real sight! For a woman, putting on makeup is really important.

Q: What was your experience like participating in the UC Irvine trial?

Dr. Klassen who runs the UC Irvine stem cell trial for RP is an amazing person. He was in the room with me during the transplant procedure. I have such a high regard and respect for Dr. Klassen because he’s been working on the cure for RP as long as I’ve had it. He’s someone who’s dedicated his life to trying to find an answer to a disease that I’ve been dealing with on a day-to-day basis.

Dr. Klassen had the opportunity to become a retinal surgeon and make much more money in a different area. But because it was too crushing to talk to patients and give them such a sad diagnosis, he decided he was going to do something about it. When I heard that, I just never forgot it. He’s a wonderful man and he’s really dedicated to this cause.

Q: How have you been an advocate for RP and blindness?

I’ve been an advocate for the visually impaired in many different aspects. I have raised money for different research foundations and donated my time as a host and an MC to various charities through radio shows. I’ve had a voice in the visually impaired community in one way or another on and off for 15 years.

I also started getting involved in Americans for Cures only a few months ago. I am helping them raise awareness about Proposition 71, which created CIRM, and the importance of funding stem cell research in the future.

I may in this lifetime get actual vision again, a real second vision. But in the meantime, I’ve been working on my higher self, which is good because a friend of mine who is totally blind reminded me today, “Kristin, just remember, don’t live for tomorrow just getting that eye sight back”. My friend was born blind. I told him he is absolutely right. I know I can lead a joyful life either way. But trust me, having a cure for RP would be the icing on the cake for me.

Q: Why is it important to be a patient advocate?

I think it’s so important from a number of different aspects, and I really felt this at the International Society for Stem Cell Research (ISSCR) conference in San Francisco this summer when certain people came to talk to me afterwards, especially researchers and scientists. They don’t get to see the perspective of the patient because they are on the other side of the fence.

I think it’s very important to be a patient advocate because when you have a personal story, it resonates with people much more than just reading about something or hearing about something on a ballot.  It’s really vital for the future. Everybody has somebody or knows somebody who had macular degeneration or became visually impaired. If they don’t, they need to be educated about it.

Q: Tell us about your Radio Show.

My radio show “Second Vision” is about personal development and reinventing yourself and your life’s vision when the first one fails. It was the first internet radio show to support the blind and visually impaired, so that’s why I’m passionate about it. I’ve had scores of authors on there over the years who’ve written amazing books about how to better yourself and personal stories from people who have overcome adversity from all different types of challenges in terms of emotional health, physical health or problems in their lives. You can find anything on the Second Vision website from interviews on Reiki and meditation to Erik Weihenmayer, the blind man who climbed the seven summits (the highest mountains of each of the seven continents).

Q: Why is stem cell research important?

I do think that stem cells will help people with blindness. I don’t know whether it will be a 100% treatment. Scientists may have to do something else along the way to perfect stem cell treatments whether it’s gene therapy or changing the number of cells or types of cells they inject into the eye. I really do have a huge amount of faith in stem cells. If they can regenerate other parts of the body, I think the eye will be no different.

To read more about Kristin Macdonald and her quest for a Second Vision, please visit her website.


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From Pig Parts to Stem Cells: Scientist Douglas Melton Wins Ogawa-Yamanaka Prize for Work on Diabetes

Since the 1920s, insulin injections have remained the best solution for managing type 1 diabetes. Patients with this disease do not make enough insulin – a hormone that regulates the sugar levels in your blood – because the insulin-producing cells, or beta cells, in their pancreas are destroyed.

Back then, it took two tons of pig parts to make eight ounces of insulin, which was enough to treat 10,000 diabetic patients for six months. Biotech and pharmaceutical companies have since developed different types of human insulin treatments that include fast and long acting versions of the hormone. It’s estimated that $22 billion will be spent on developing insulin products for patients this year and that costs will rise to $32 billion in the year 2019.

These costs are necessary to keep insulin-dependent diabetes patients alive and healthy, but what if there was a different, potentially simpler solution to manage diabetes? One that looks to insulin-producing beta cells as the solution rather than daily hormone shots?

Douglas Melton Receives Stem Cell Prize for Work on Diabetes

Harvard scientist Douglas Melton envisions a world where one day, insulin-dependent diabetic patients are given stem cell transplants rather than shots to manage their diabetes. In the 90s, Melton’s son was diagnosed with type 1 diabetes. Motivated by his son’s diagnosis, Melton dedicated the focus of his research on understanding how beta cells develop from stem cells in the body and also in a cell culture dish.

Almost 30 years later, Melton has made huge strides towards understanding the biology of beta cell development and has generated methods to “reprogram” or coax pluripotent stem cells into human beta cells.

Melton was honored for his important contributions to stem cell and diabetes research at the second annual Ogawa-Yamanaka Stem Cell Prize ceremony last week at the Gladstone Institutes. This award recognizes outstanding scientists that are translating stem cell research from the lab to clinical trials in patients.

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Deepak Srivastava, director of the Gladstone Institute of Cardiovascular Disease, explained why Melton was selected as this year’s prize winner:

Deepak Srivastava, Gladstone Institutes

Deepak Srivastava, Gladstone Institutes

“Doug’s research on genetic markers expressed during pancreas development have led to a reliable way to reprogram stem cells into human beta cells. His work provides the foundation for the ultimate goal of transplantable, patient-specific beta cells.”

 

Making Beta Cells for Patients

During the awards ceremony, Melton discussed his latest work on generating beta cells from human stem cells and how this technology could transform the way insulin-dependent patients are treated.

Douglas Melton, Harvard University.

Douglas Melton, Harvard University.

“I don’t mean to say that this [insulin treatment] isn’t a good idea. That’s keeping these people alive and in good health,” said Melton during his lecture. “What I want to talk about is a different approach. Rather than making more and better insulins and providing them by different medical devices, why not go back to nature’s solution which is the beta cells that makes the insulin?”

Melton first described his initial research on making pancreatic beta cells from embryonic and induced pluripotent stem cells in a culture dish. He described the power of this system for not only modeling diabetes, but also screening for potential drugs, and testing new therapies in animal models.

He also mentioned how he and his colleagues are developing methods to manufacture large amounts of human beta cells derived from pluripotent stem cells for use in patients. They are able to culture stem cells in large spinning flasks that accelerate the growth and development of pluripotent stem cells into billions of human beta cells.

Challenges and Future of Stem-Cell Derived Diabetes Treatments

Melton expressed a positive outlook for the future of stem cell-derived treatments for insulin-dependent diabetes, but he also mentioned two major challenges. The first is the need for better control over the methods that make beta cells from stem cells. These methods could be more efficient and generate higher numbers of beta cells (beta cells make up 16% of stem cell-derived cells using their current culturing methods). The second is preventing an autoimmune attack after transplanting the stem-cell derived beta cells into patients.

Melton and other scientists are already working on improving techniques to make more beta cells from stem cells. As for preventing transplanted beta cells from being attacked by the patient’s immune system, Melton described two possibilities: using an encapsulation device or biological protection to mask the transplanted cells from an attack.

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He mentioned a CIRM-funded clinical trial by ViaCyte, which is testing an encapsulation device that is placed under the skin. The device contains embryonic stem cell-derived pancreatic progenitor cells that develop into beta cells that secrete insulin into the blood stream. The device also prevents the immune system from attacking and killing the beta cells.

Melton also discussed a biological approach to protecting transplanted beta cells. In collaboration with Dan Anderson at MIT, they coated stem cell-derived beta cells in a biomaterial called alginate, which comes from seaweed. They injected alginate microcapsule-containing beta cells into diabetic mice and were able control their blood sugar levels.

At the end of his talk, Melton concluded that he believes that beta cell transplantation in an immunoprotective device containing stem cell-derived cells will have the most benefit for diabetes patients.

Gladstone Youtube video of Douglas Melton’s lecture at the Ogawa-Yamanaka Prize lecture.


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