CIRM weekly stem cell roundup: minibrain model of childhood disease; new immune insights; patient throws out 1st pitch

New human Mini-brain model of devastating childhood disease.
The eradication of Aicardi-Goutieres Syndrome (AGS) can’t come soon enough. This rare but terrible inherited disease causes the immune system to attack the brain. The condition leads to microcephaly (an abnormal small head and brain size), muscle spasms, vision problems and joint stiffness during infancy. Death or a persistent comatose state is common by early childhood. There is no cure.

Though animal models that mimic AGS symptoms are helpful, they don’t reflect the human disease closely enough to provide researchers with a deeper understanding of the mechanisms of the disease. But CIRM-funded research published this week may be a game changer for opening up new therapeutic strategies for the children and their families that are suffering from AGS.

Organoid mini-brains are clusters of cultured cells self-organized into miniature replicas of organs. Image courtesy of Cleber A. Trujillo, UC San Diego.

To get a clearer human picture of the disease, Dr. Alysson Muotri of UC San Diego and his team generated AGS patient-derived induced pluripotent stem cells (iPSCs). These iPSCs were then grown into “mini-brains” in a lab dish. As described in Cell Stem Cell, their examination of the mini-brains revealed an excess of chromosomal DNA in the cells. This abnormal build up causes various toxic effects on the nerve cells in the mini-brains which, according to Muotri, had the hallmarks of AGS in patients:

“These models seemed to mirror the development and progression of AGS in a developing fetus,” said Muotri in a press release. “It was cell death and reduction when neural development should be rising.”

In turns out that the excess DNA wasn’t just a bunch of random sequences but instead most came from so-called LINE1 (L1) retroelements. These repetitive DNA sequences can “jump” in and out of DNA chromosomes and are thought to be remnants of ancient viruses in the human genome. And it turns out the cell death in the mini-brains was caused by the immune system’s anti-viral response to these L1 retroelements. First author Charles Thomas explained why researchers may have missed this in their mouse models:

“We uncovered a novel and fundamental mechanism, where chronic response to L1 elements can negatively impact human neurodevelopment. This mechanism seems human-specific. We don’t see this in the mouse.”

The team went on to test the anti-retroviral effects of HIV drugs on their AGS models. Sure enough, the drugs decreased the amount of L1 DNA and cell growth rebounded in the mini-brains. The beauty of using already approved drugs is that the route to clinical trials is much faster and in fact a European trial is currently underway.

For more details, watch this video interview with Dr. Muotri:

New findings about immune cell development may open door to new cancer treatments
For those of you who suffer with seasonal allergies, you can blame your sniffling and sneezing on an overreaction by mast cells. These white blood cells help jump start the immune system by releasing histamines which makes blood vessels leaky allowing other immune cells to join the battle to fight disease or infection. Certain harmless allergens like pollen are mistaken as dangerous and can also cause histamine release which triggers tearing and sneezing.

Mast cells in lab dish. Image: Wikipedia.

Dysfunction of mast cells are also involved in some blood cancers. And up until now, it was thought a protein called stem cell factor played the key role in the development of blood stem cells into mast cells. But research reported this week by researchers at Karolinska Institute and Uppsala University found cracks in that previous hypothesis. Their findings published in Blood could open the door to new cancer therapies.

The researchers examine the effects of the anticancer drug Glivec – which blocks the function of stem cell factor – on mast cells in patients with a form of leukemia. Although the number of mature mast cells were reduced by the drug, the number of progenitor mast cells were not. The progenitors are akin to teenagers in that they’re at an intermediate stage of development, more specialized than stem cells but not quite mast cells. The team went on to confirm that stem cell factor was not required for the mast cell progenitors to survive, multiply and mature. Instead, their work identified two other growth factors, interleukin 3 and 6, as important for mast cell development.

In a press release, lead author Joakim Dahlin, explained how these new insights could lead to new therapies:

“The study increases our understanding of how mast cells are formed and could be important in the development of new therapies, for example for mastocytosis for which treatment with imatinib/Glivec is not effective. One hypothesis that we will now test is whether interleukin 3 can be a new target in the treatment of mast cell-driven diseases.”

Patient in CIRM-funded trial regains use of arms, hands and fingers will throw 1st pitch in MLB game.
We end this week with some heart-warming news from Asterias Biotherapeutics. You avid Stem Cellar readers will remember our story about Lucas Lindner several weeks back. Lucas was paralyzed from the neck down after a terrible car accident. Shortly after the accident, in June of 2016, he enrolled in Asterias’ CIRM-funded trial testing an embryonic stem cell-based therapy to treat his injury. And this Sunday, August 13th, we’re excited to report that due to regaining the use of his arms, hands and fingers since the treatment, he will throw out the first pitch of a Major League Baseball game in Milwaukee. Congrats to Lucas!

For more about Lucas’ story, watch this video produced by Asterias Biotherapeutics:

Scientists fix heart disease mutation in human embryos using CRISPR

Last week the scientific community was buzzing with the news that US scientists had genetically modified human embryos using CRISPR gene editing technology. While the story broke before the research was published, many journalists and news outlets weighed in on the study’s findings and the ethical implications they raise. We covered this initial burst of news in last week’s stem cell stories that caught our eye.

Shoukhrat Mitalipov (Leah Nash, New York Times)

After a week of suspense, the highly-anticipated study was published yesterday in the journal Nature. The work was led by senior author Dr. Shoukhrat Mitalipov from Oregon Health and Sciences University (and a member of CIRM’s Grants Working Group, the panel of experts who review applications to us for funding) in collaboration with scientists from the Salk Institute and Korea’s Institute for Basic Science.

In brief, the study revealed that the teams’ CRISPR technology could correct a genetic mutation that causes a disease called hypertrophic cardiomyopathy (HCM) in 72% of human embryos without causing off-target effects, which are unwanted genome modifications caused by CRISPR. These findings are a big improvement over previous studies by other groups that had issues with off-target effects and mosaicism, where CRISPR only correctly modifies mutations in some but not all cells in an embryo.

Newly fertilized eggs before gene editing, left, and embryos after gene editing and a few rounds of cell division. (Image from Shoukrat Mitalipov in New York Times)

Mitalipov spoke to STATnews about a particularly interesting discovery that he and the other scientists made in the Nature study,

“The main finding is that the CRISPR’d embryos did not accept the “repair DNA” that the scientists expected them to use as a replacement for the mutated gene deleted by CRISPR, which the embryos inherited from their father. Instead, the embryos used the mother’s version of the gene, called the homologue.”

Sharon Begley, the author of the STATnews article, argued that this discovery means that “designer babies” aren’t just around the corner.

“If embryos resist taking up synthetic DNA after CRISPR has deleted an unwanted gene, then “designer babies,” created by inserting a gene for a desirable trait into an embryo, will likely be more difficult than expected.”

Ed Yong from the Atlantic also took a similar stance towards Mitalipov’s study in his article titled “The Designer Baby Era is Not Upon Us”. He wrote,

“The bigger worry is that gene-editing could be used to make people stronger, smarter, or taller, paving the way for a new eugenics, and widening the already substantial gaps between the wealthy and poor. But many geneticists believe that such a future is fundamentally unlikely because complex traits like height and intelligence are the work of hundreds or thousands of genes, each of which have a tiny effect. The prospect of editing them all is implausible. And since genes are so thoroughly interconnected, it may be impossible to edit one particular trait without also affecting many others.”

Dr. Juan Carlos Izpisua Belmonte, who’s a corresponding author on the paper and a former CIRM grantee from the Salk Institute, commented on the impact that this research could have on human health in a Salk news release.

Co-authors Juan Carlos Izpisua Belmonte and Jun Wu. (Salk Institute)

“Thanks to advances in stem cell technologies and gene editing, we are finally starting to address disease-causing mutations that impact potentially millions of people. Gene editing is still in its infancy so even though this preliminary effort was found to be safe and effective, it is crucial that we continue to proceed with the utmost caution, paying the highest attention to ethical considerations.”

Pam Belluck from The New York Times also suggested that this research could have a significant impact on how we prevent disease in newborns.

“This research marks a major milestone and, while a long way from clinical use, it raises the prospect that gene editing may one day protect babies from a variety of hereditary conditions.”

So when will the dawn of CRISPR babies arrive? Ed Yong took a stab at answering this million dollar question with help from experts in the field.

“Not for a while. The technique would need to be refined, tested on non-human primates, and shown to be safe. “The safety studies would likely take 10 to 15 years before FDA or other regulators would even consider allowing clinical trials,” wrote bioethicist Hank Greely in a piece for Scientific American. “The Mitalipov research could mean that moment is 9 years and 10 months away instead of 10 years, but it is not close.” In the meantime, Mitalipov’s colleague Sanjiv Kaul says, “We’ll get the method to perfection so that when it’s possible to use it in a clinical trial, we can.”

Stem Cell Stories that Caught our Eye: CRISPRing Human Embryos, brain stem cells slow aging & BrainStorm ALS trial joins CIRM Alpha Clinics

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

Scientists claim first CRISPR editing of human embryos in the US.

Here’s the big story this week. Scientists from Portland, Oregon claim they genetically modified human embryos using the CRISPR/Cas9 gene editing technology. While their results have yet to be published in a peer review journal (though the team say they are going to be published in a prominent journal next month), if they prove true, the study will be the first successful attempt to modify human embryos in the US.

A representation of an embryo being fertilized. Scientists can inject CRISPR during fertilization to correct genetic disorders. (Getty Images).

Steve Connor from MIT Technology Review broke the story earlier this week noting that the only reports of human embryo modification were published by Chinese scientists. The China studies revealed troubling findings. CRISPR caused “off-target” effects, a situation where the CRISPR machinery randomly introduces genetic errors in a cell’s DNA, in the embryos. It also caused mosaicism, a condition where the desired DNA sequences aren’t genetically corrected in all the cells of an embryo producing an individual with cells that have different genomes. Putting aside the ethical conundrum of modifying human embryos, these studies suggested that current gene editing technologies weren’t accurate enough to safely modify human embryos.

But a new chapter in human embryo modification is beginning. Shoukhrat Mitalipov (who is a member of CIRM’s Grants Working Group, the panel of scientific experts that reviews our funding applications) and his team from the Oregon Health and Science University said that they have developed a method to successfully modify donated human embryos that avoids the problems experienced by the Chinese scientists. The team found that introducing CRISPR at the same time an embryo was being fertilized led to successful correction of disease-causing mutations while avoiding mosaicism and “off-target” effects. They grew these embryos for a few days to confirm that the genetic modifications had worked before destroying them.

The MIT piece quoted a scientist who knows of Mitalipov’s work,

“It is proof of principle that it can work. They significantly reduced mosaicism. I don’t think it’s the start of clinical trials yet, but it does take it further than anyone has before.”

Does this discovery, if it’s true, open the door further for the creation of designer babies? For discussions about the future scientific and ethical implications of this research, I recommend reading Paul Knoepfler’s blog, this piece by Megan Molteni in Wired Magazine and Jessica Berg’s article in The Conversation.

Brain stem cells slow aging in mice

The quest for eternal youth might be one step closer thanks to a new study published this week in the journal Nature. Scientists from the Albert Einstein College of Medicine in New York discovered that stem cells found in an area of the brain called the hypothalamus can slow the aging process in mice.

The hypothalamus is located smack in the center of your brain near the brain stem. It’s responsible for essential metabolic functions such as making and secreting hormones, managing body temperature and controlling feelings of hunger and thirst. Because the body’s metabolic functions decline with age, scientists have suspected that the hypothalamus plays a role in aging.

The mouse hypothalamus. (NIH, Wikimedia).

In the current study, the team found that stem cells in the hypothalamus gradually disappear as mice age. They were curious whether the disappearance of these stem cells could jump start the aging process. When they removed these stem cells, the mice showed more advanced mental and physical signs of aging compared to untreated mice.

They also conducted the opposite experiment where they transplanted hypothalamic stem cells taken from baby mice (the idea being that these stem cells would exhibit more “youthful” qualities) into the brains of middle-aged mice and saw improvements in mental and physical functions and a 10% increase in lifespan.

So what is it about these specific stem cells that slows down aging? Do they replenish the aging brain with new healthy cells or do they secrete factors that keep the brain healthy? Interestingly, the scientists found that these stem cells secreted vesicles that contained microRNAs, which are molecules that regulate gene expression by turning genes on or off.

They injected these microRNAs into the brains of middle-aged mice and found that they reversed symptoms of aging including cognitive decline and muscle degeneration. Furthermore, when they removed hypothalamic stem cells from middle-aged mice and treated them with the microRNAs, they saw the same anti-aging effects.

In an interview with Nature News, senior author on the study, Dongsheng Cai, commented that hypothalamic stem cells could have multiple ways of regulating aging and that microRNAs are just one of their tools. For this research to translate into an anti-aging therapy, “Cai suspects that anti-ageing therapies targeting the hypothalamus would need to be administered in middle age, before a person’s muscles and metabolism have degenerated beyond a point that could be reversed.”

This study and its “Fountain of Youth” implications has received ample attention from the media. You can read more coverage from The Scientist, GenBio, and the original Albert Einstein press release.

BrainStorm ALS trial joins the CIRM Alpha Clinics

Last month, the CIRM Board approved $15.9 million in funding for BrainStorm Cell Therapeutic’s Phase 3 trial that’s testing a stem cell therapy to treat patients with a devastating neurodegenerative disease called amyotrophic lateral sclerosis or ALS (also known as Lou Gehrig’s disease).

The stem cell therapy, called NurOwn®, is made of mesenchymal stem cells extracted from a patient’s bone marrow. The stem cells are genetically modified to secrete neurotrophic factors that keep neurons in the brain healthy and prevent their destruction by diseases like ALS.

BrainStorm has tested NurOwn in early stage clinical trials in Israel and in a Phase 2 study in the US. These trials revealed that the treatment was “safe and well tolerated” and that “NurOwn also achieved multiple secondary efficacy endpoints, showing clear evidence of a clinically meaningful benefit.  Notably, response rates were higher for NurOwn-treated subjects compared to placebo at all time points in the study out to 24 weeks.”

This week, BrainStorm announced that it will launch its Phase 3 CIRM-funded trial at the UC Irvine (UCI) CIRM Alpha Stem Cell Clinic. The Alpha Clinics are a network of top medical centers in California that specialize in delivering high quality stem cell clinical trials to patients. UCI is one of four medical centers including UCLA, City of Hope, and UCSD, that make up three Alpha Clinics currently supporting 38 stem cell trials in the state.

Along with UCI, BrainStorm’s Phase 3 trial will also be conducted at two other sites in the US: Mass General Hospital in Boston and California Pacific Medical Center in San Francisco. Chaim Lebovits, President and CEO, commented,

“We are privileged to have UCI and Dr. Namita Goyal join our pivotal Phase 3 study of NurOwn. Adding UCI as an enrolling center with Dr. Goyal as Principal Investigator will make the treatment more accessible to patients in California, and we welcome the opportunity to work with this prestigious institution.”

Before the Phase 3 trial can launch at UCI, it needs to be approved by our federal regulatory agency, the Food and Drug Administration (FDA), and an Institutional Review Board (IRB), which is an independent ethics committee that reviews biomedical research on human subjects. Both these steps are required to ensure that a therapy is safe to test in patients.

With promising data from their Phase 1 and 2 trials, BrainStorm’s Phase 3 trial will likely get the green light to move forward. Dr. Goyal, who will lead the trial at the UCI Alpha Clinic, concluded:

“NurOwn is a very promising treatment with compelling Phase 2 data in patients with ALS; we look forward to further advancing it in clinical development and confirming the therapeutic benefit with Brainstorm.”

Stories that caught our eye: Spinal cord injury trial milestone, iPS for early cancer diagnosis, and storing videos in DNA

Spinal cord injury clinical trial hits another milestone (Kevin McCormack)
We began the week with good news about our CIRM-funded clinical trial with Asterias for spinal cord injury, and so it’s nice to end the week with more good news from that same trial. On Wednesday, Asterias announced it had completed enrolling and dosing patients in their AIS-B 10 million cell group.

asterias

People with AIS-B spinal cord injuries have some level of sensation and feeling but very little, if any, movement below the site of injury site. So for example, spinal cord injuries at the neck, would lead to very limited movement in their arms and hands. As a result, they face a challenging life and may be dependent on help in performing most daily functions, from getting out of bed to eating.astopc1

In another branch of the Asterias trial, people with even more serious AIS-A injuries – in which no feeling or movement remains below the site of spinal cord injury – experienced improvements after being treated with Asterias’ AST-OPC1 stem cell therapy. In some cases the improvements were quite dramatic. We blogged about those here.

In a news release Dr. Ed Wirth, Asterias’ Chief Medical Officer, said they hope that the five people treated in the AIS-B portion of the trial will experience similar improvements as the AIS-A group.

“Completing enrollment and dosing of the first cohort of AIS-B patients marks another important milestone for our AST-OPC1 program. We have already reported meaningful improvements in arm, hand and finger function for AIS-A patients dosed with 10 million AST-OPC1 cells and we are looking forward to reporting initial efficacy and safety data for this cohort early in 2018.”

Asterias is already treating some AIS-A patients with 20 million cells and hopes to start enrolling AIS-B patients for the 20 million cell therapy later this summer.

Earlier diagnosis of pancreatic cancer using induced pluripotent stem cells Reprogramming adult cells to an embryonic stem cell-like state is as common in research laboratories as hammers and nails are on a construction site. But a research article in this week’s edition of Science Translational Medicine used this induced pluripotent stem cell (iPSC) toolbox in a way I had never read about before. And the results of the study may lead to earlier detection of pancreatic cancer, the fourth leading cause of cancer death in the U.S.

Zaret STM pancreatic cancer tissue July 17

A pancreatic ductal adenocarcinoma
Credit: The lab of Ken Zaret, Perelman School of Medicine, University of Pennsylvania

We’ve summarized countless iPSCs studies over the years. For example, skin or blood samples from people with Parkinson’s disease can be converted to iPSCs and then specialized into brain cells to provide a means to examine the disease in a lab dish. The starting material – the skin or blood sample – typically has no connection to the disease so for all intents and purposes, it’s a healthy cell. It’s only after specializing it into a nerve cell that the disease reveals itself.

But the current study by researchers at the University of Pennsylvania used late stage pancreatic cancer cells as their iPSC cell source. One of the reasons pancreatic cancer is thought to be so deadly is because it’s usually diagnosed very late when standard treatments are less effective. So, this team aimed to reprogram the cancer cells back into an earlier stage of the cancer to hopefully find proteins or molecules that could act as early warning signals, or biomarkers, of pancreatic cancer.

Their “early-stage-cancer-in-a-dish” model strategy was a success. The team identified a protein called thrombospodin-2 (THBS2) as a new candidate biomarker. As team lead, Dr. Ken Zaret, described in a press release, measuring blood levels of THBS2 along with a late-stage cancer biomarker called CA19-9 beat out current detection tests:

“Positive results for THBS2 or CA19-9 concentrations in the blood consistently and correctly identified all stages of the cancer. Notably, THBS2 concentrations combined with CA19-9 identified early stages better than any other known method.”

DNA: the ultimate film archive device?
This last story for the week isn’t directly related to stem cells but is too cool to ignore. For the first time ever, researchers at Harvard report in Nature that they have converted a video into a DNA sequence which was then inserted into bacteria. As Gina Kolata states in her New York Times article about the research, the study represents the ultimate data archive system which can “be retrieved at will and multiplied indefinitely as the host [bacteria] divides and grows.”

A video file is nothing but a collection of “1s” and “0s” of binary code which describe the makeup of each pixel in each frame of a movie. The researchers used the genetic code within DNA to describe each pixel in a short clip of one of the world’s first motion pictures: a galloping horse captured by Eadward Muybridge in 1878.

Horse_1080.gif

The resulting DNA sequence was then inserted into the chromosome of E.Coli., a common bacteria that lives in your intestines, using the CRISPR gene editing method. The video code was still retrievable after the bacteria was allowed to multiply.

The Harvard team envisions applications well beyond a mere biological hard drive. Dr. Seth Shipman, an author of the study, told Paul Rincon of BBC news that he thinks this cell system could be placed in various parts of the body to analyze cell function and “encode information about what’s going on in the cell and what’s going on in the cell environment by writing that information into their own genome”.

Perhaps then it could be used to monitor the real-time activity of stem cell therapies inside the body. For now, I’ll wait to hear about that in some upcoming science fiction film.

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.

Wall Street Journal features CIRM-funded clinical trials aiming for a diabetes cure

We think CIRM-funded clinical trials hold so much promise that it doesn’t surprise us when major news organizations publish stories about these projects that aim to provide stem cell treatments to patients with unmet medical needs. But we certainly don’t mind the attention!

This past Saturday, for example, the Wall Street Journal featured two CIRM-funded clinical trials, run by ViaCyte and Caladrius, in an article covering cutting-edge research approaches to tackling type 1 diabetes. Also mentioned was Semma Therapeutics, who have a CIRM-funded pre-clinical diabetes research grant.

ViaCyte is tackling diabetes with implantable devices containing stem cell-based products that release insulin on demand rather than requiring continual monitoring of blood sugar level. Image: ViaCyte.

People with type 1 diabetes lack insulin, a hormone that’s critical for transporting blood sugar, digested from the food we eat, into our energy-hungry organs and tissues. They lack insulin because the insulin-producing beta cells in the pancreas have been attacked and killed off by the body’s own immune system. Without insulin, blood sugar levels go through the roof and over time that build up can cause vision loss, kidney disease, nerve damage, heart disease and the list goes on.

Families unaffected by type 1 diabetes often mistake insulin injections as a cure for diabetes. But they’re not. Julia Greenstein, vice president of discovery research for the JDRF, states injected insulin’s limitation very concisely but clearly in the WSJ article:

“It is [in] no way an easy life trying to manage blood glucose.”

Her statement echoes the thoughts of Chris Stiehl who we interviewed for a video a few years ago:

“It’s a 24-hour a day job, 7 days a week you never get a day off. I would give anything for a day off. Just to not have to think about it. Besides all the things you have to do for your work and your family and everything, you have to be constantly thinking: “What’s my blood sugar? What have I eaten? Have I exercised too much or too little? How much insulin should I take based on the exercise I just did? Gee by the way is my insulin pump running out of insulin?

The WSJ article points out that a pancreas or beta cell transplant, received from a deceased donor, is currently the best option for long-term treatment of type 1 diabetes. But there are big drawbacks and limitations to this approach: the pancreas transplant requires major surgery, both require life-long immunosuppressing drugs that can cause serious infection and cancer and donor organs and cells are hard to come by.

That’s where regenerative medicine technology comes into the picture. The article goes on to highlight ViaCyte’s therapeutic product, PEC-EncapTM which is composed of embryonic stem cell-derived insulin-producing beta cells that are encased by a capsule that is transplanted under the skin. The capsule has pores that allow blood glucose and insulin to flow freely but protects the cell product from destruction from the body’s immune cells.

Because the cell product stems from, er, stem cells, there’s the potential of a limitless supply that doesn’t rely on cadavers.

Dr. Gordon Weir, a Harvard Medical School professor and diabetes researcher at the Joslin Diabetes Center in Boston, spoke about the excitement of such a device along with a reality check:

“Everyone’s waiting for the next generation of beta-cell replacement that hopefully will change the whole way in which we treat diabetes. In spite of the excitement and extraordinary things that have happened in the last 10 years, there are still a lot of challenges.”

Indeed, since beginning the clinical trial in 2014, ViaCyte has encountered some speed bumps. They had hoped that blood vessels growing around but not into the device would facilitate the transfer of blood sugar into the device where the beta cells would sense the level of sugar and release the appropriate amount of insulin. But it turns out that some cells of the immune system cells mucked up the blood vessel network. The company is working on improvements to the device to get the clinical trial back on track in the next 24 months. To jump start that effort they recently secured a partnership with the makers of Gore-Tex fabrics who also specialize in medical implantable devices.

That collaboration is also motivating a next generation device called PEC-DirectTM which contains larger pores that would allow direct interaction between the body’s blood vessels and the beta cells inside the device. Because of the larger openings, immune cells could infiltrate the device and so immunosuppressive drugs would be needed in this case. But for patients with severe type 1 diabetes, this approach would be a more available treatment source compared to cadaver cells or organs.

The WSJ article also discusses the CIRM-funded Caladrius clinical trial that takes quite a different approach to treating type 1 diabetes. The company is trying to disarm the T cells that attack the body’s own pancreatic beta cells. Because diabetics don’t lose all their beta cells at once, this approach could help maintain the insulin-producing cells that are still intact. The company’s strategy is to reprogram these attacking T-cells to convert them into so-called regulatory T-cells that act as a natural inhibitor of the immune response.

While each company works diligently on their own approach, eager patients are routing for both. Dara Melnick, of Woodbury, N.Y., who was diagnosed with type 1 diabetes at 8 years old and is now 36, summed up the patient’s perspective perfectly in the article:

“A cure would be the sweetest thing I could ever taste.”

Stories that caught our eye: An antibody that could make stem cell research safer; scientists prepare for clinical trial for Parkinson’s disease; and the stem cell scientist running for Congress

Antibody to make stem cells safer:

There is an old Chinese proverb that states: ‘What seems like a blessing could be a curse’. In some ways that proverb could apply to stem cells. For example, pluripotent stem cells have the extraordinary ability to turn into many other kinds of cells, giving researchers a tool to repair damaged organs and tissues. But that same ability to turn into other kinds of cells means that a pluripotent stem cell could also turn into a cancerous one, endangering someone’s life.

A*STAR

Researchers at the A*STAR Bioprocessing Technology Institute: Photo courtesy A*STAR

Now researchers at the Agency for Science, Technology and Research (A*STAR) in Singapore may have found a way to stop that happening.

When you change, or differentiate, stem cells into other kinds of cells there will always be some of the original material that didn’t make the transformation. Those cells could turn into tumors called teratomas. Scientists have long sought for a way to identify pluripotent cells that haven’t differentiated, without harming the ones that have.

The team at A*STAR injected mice with embryonic stem cells to generate antibodies. They then tested the ability of the different antibodies to destroy pluripotent stem cells. They found one, they called A1, that did just that; killing pluripotent cells but leaving other cells unharmed.

Further study showed that A1 worked by attaching itself to specific molecules that are only found on the surface of pluripotent cells.

In an article on Phys.Org Andre Choo, the leader of the team, says this gives them a tool to get rid of the undifferentiated cells that could potentially cause problems:

“That was quite exciting because it now gives us a view of the mechanism that is responsible for the cell-killing effect.”

Reviving hope for Parkinson’s patients:

In the 1980’s and 1990’s scientists transplanted fetal tissue into the brains of people with Parkinson’s disease. They hoped the cells in the tissue would replace the dopamine-producing cells destroyed by Parkinson’s, and stop the progression of the disease.

For some patients the transplants worked well. For some they produced unwanted side effects. But for most they had little discernible effect. The disappointing results pretty much brought the field to a halt for more than a decade.

But now researchers are getting ready to try again, and a news story on NPR explained why they think things could turn out differently this time.

tabar-viviane

Viviane Tabar, MD; Photo courtesy Memorial Sloan Kettering Cancer Center

Viviane Tabar, a stem cell researcher at Memorial Sloan Kettering Cancer Center in New York, says in the past the transplanted tissue contained a mixture of cells:

“What you were placing in the patient was just a soup of brain. It did not have only the dopamine neurons, which exist in the tissue, but also several different types of cells.”

This time Tabar and her husband, Lorenz Studer, are using only cells that have been turned into the kind of cell destroyed by the disease. She says that will, hopefully, make all the difference:

“So you are confident that everything you are putting in the patient’s brain will consist of  the right type of cell.”

Tabar and Studer are now ready to apply to the Food and Drug Administration (FDA) for permission to try their approach out in a clinical trial. They hope that could start as early as next year.

Hans runs for Congress:

Keirstead

Hans Keirstead: Photo courtesy Orange County Register

Hans Keirstead is a name familiar to many in the stem cell field. Now it could become familiar to a lot of people in the political arena too, because Keirstead has announced he’s planning to run for Congress.

Keirstead is considered by some to be a pioneer in stem cell research. A CIRM grant helped him develop a treatment for spinal cord injury.  That work is now in a clinical trial being run by Asterias. We reported on encouraging results from that trial earlier this week.

Over the years the companies he has founded – focused on ovarian, skin and brain cancer – have made him millions of dollars.

Now he says it’s time to turn his sights to a different stage, Congress. Keirstead has announced he is going to challenge 18-term Orange County Republican Dana Rohrabacher.

In an article in the Los Angeles Times, Keirstead says his science and business acumen will prove important assets in his bid for the seat:

“I’ve come to realize more acutely than ever before the deficits in Congress and how my profile can actually benefit Congress. I’d like to do what I’m doing but on a larger stage — and I think Congress provides that, provides a forum for doing the greater good.”

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.

Stories that caught our eye: color me stem cells, delivering cell therapy with nanomagnets, and stem cell decisions

Nanomagnets: the future of targeted stem cell therapies? Your blood vessels are made up of tightly-packed endothelial cells. This barrier poses some big challenges for the delivery of drugs via the blood. While small molecules are able make their way through the small gaps in the blood vessel walls, larger drug molecules, including proteins and cells, are not able to penetrate the vessel to get therapies to diseased areas.

This week, researchers at Rice University report in Nature Communications on an ingenious technique using tiny magnets that may overcome this drug delivery problem.

170608072913_1_900x600

At left, the nanoparticles are evenly distributed among the microtubules that help give the cells their shape. At right, after a magnetic field is applied, the nanoparticles are pulled toward one end of the cells and change their shapes. Credit: Laboratory of Biomolecular Engineering and Nanomedicine/Rice University

Initial studies showed that adding magnetic nanoparticles to the endothelial cells and then applying a magnetic field affected the cells’ internal scaffolding, called microtubules. These structures are responsible for maintaining the tight cell to cell connections. The team took the studies a step further by growing the cells in specialized petri dishes containing tiny, tube-shaped channels. Applying a magnetic field to the cells caused the cell-cell junctions to form gaps, making the blood vessel structures leaky. Simply turning off the magnetic field closed up the gaps within a few hours.

Though a lot of research remains, the team aims to apply this on-demand induction of cell leakiness along with adding the magnetic nanoparticles to stem cell therapy products to help target the treatment to specific area. In a press release, team leader Dr. Gang Bao spoke about possible applications to arthritis therapy:

“The problem is how to accumulate therapeutic stem cells around the knee and keep them there. After injecting the nanoparticle-infused cells, we want to put an array of magnets around the knee to attract them.”

To differentiate or not differentiate: new insights During the body’s development, stem cells must differentiate, or specialize, into functional cells – like liver, heart, brain. But once that specialization occurs, the cells lose their pluripotency, or the ability to become any type of cell. So, stem cells must balance the need to differentiate with the need to make copies of itself to maintain an adequate supply of stem cells to complete the development process. And even after a fully formed baby is born, it’s still critical for adult stem cells to balance the need to regenerate damaged tissue versus stashing away a pool of stem cells in various organs for future regeneration and replacement of damaged or diseased tissues.

genetic-cross-talk.png

Visualizing activation of Nanog gene activity (bright green spot) within cell nucleus. 
Image: Courtesy of Bony De Kumar, Ph.D., and Robb Krumlauf, Ph.D., Stowers Institute for Medical Research

A report this week in the Proceedings of the National Academy of Sciences finds evidence that the two separate processes – differentiation and pluripotency – directly communicate with each other as way to ensure a proper balance between the two states.

The study, carried out by researchers at Stowers Institute for Medical Research in Kansas City, Missouri, focused on the regulation of two genes: Nanog and Hox. Nanog is critical for maintaining a stem cell’s ability to become a specialized cell type. In fact, it’s one of the four genes initially used to reprogram adult cells back into induced pluripotent stem cells. The Hox gene family is responsible for generating a blueprint of the body plan in a developing embryo. Basically, the pattern of Hox gene activity helps generate the body plan, basically predetermining where the various body parts and organs will form.

Now, both Nanog and Hox proteins act by binding to DNA and turning on a cascade of other genes that ultimately maintain pluripotency or promote differentiation. By examining these other genes, the researchers were surprised to find that both Nanog and Hox were bound to both the pluripotency and differentiation genes. They also found that Nanog and Hox can directly inhibit each other. Taken together, these results suggest that exquisite control of both processes occurs cross regulation of gene activity.

Dr. Robb Krumlauf one of authors on the paper talked about the significance of the result in a press release:

“Over the past 10 to 20 years, biologists have shown that cells are actively assessing their environment, and that they have many fates they can choose. The regulatory loops we’ve found show how the dynamic nature of cells is being maintained.”

Color me stem cells Looking to improve your life and the life of those around you? Then we highly recommend you pay a visit to today’s issue of Right Turn, a regular Friday feature of  Signals, the official blog of CCRM, Canada’s public-private consortium supporting the development of regenerative medicine technologies.

COLOURING-SHEETS-COLLAGE-768x948.jpg

Collage sample of CCRM’s new coloring sheets. Image: copyright CCRM 2017

As part of an public outreach effort they have created four new coloring sheets that depict stem cells among other sciency topics. They’ve set up a DropBox link to download the pictures so you can get started right away.

Adult coloring has swept the nation as the hippest new pastime. And it’s not just a frivolous activity, as coloring has been shown to have many healthy benefits like reducing stressed and increasing creativity. Just watch any kid who colors. In fact, share these sheet with them, it’s intended for children too.

Throwback Thursday: Progress to a Cure for Diseases of Blindness

Welcome back to our “Throwback Thursday” series on the Stem Cellar. Over the years, we’ve accumulated an arsenal of exciting stem cell stories about advances towards stem cell-based cures for serious diseases. This month we’re featuring stories about CIRM-funded clinical trials for blindness.

2017 has been an exciting year for two CIRM-funded clinical trials that are testing stem cell-based therapies for diseases of blindness. A company called Regenerative Patch Technologies (RPT) is transplanting a sheet of embryonic stem cell-derived retinal support cells into patients with the dry form of age-related macular degeneration, a disease that degrades the eye’s macula, the center of the retina that controls central vision. The other trial, sponsored by a company called jCyte, is using human retinal progenitor cells to treat retinitis pigmentosa, a rare genetic disease that destroys the light-sensing cells in the retina, causing tunnel vision and eventually blindness.

 

Both trials are in the early stages, testing the safety of their respective stem cell therapies. But the teams are hopeful that these treatments will stop the progression of or even restore some form of vision in patients. In the past few months, both RPT and jCyte have shared exciting news about the progress of these trials which are detailed below.

Macular Degeneration Trial Gets a New Investor

In April, RPT announced that they have a new funding partner to further develop their stem cell therapy for age-related macular degeneration (AMD). They are partnering with Japan’s Santen Pharmaceutical Company, which specializes in developing ophthalmology or eye therapies.

AMD is the leading cause of blindness in elderly people and is projected to affect almost 200 million people worldwide by 2020. There is no cure or treatment that can restore vision in AMD patients, but stem cell transplants offer a potential therapeutic option.

RPT believes that their newfound partnership with Santen will accelerate the development of their stem cell therapy and ultimately fulfill an unmet medical need. RPT’s co-founder, Dr. Dennis Clegg, commented in a CIRM news release, “the ability to partner with a global leader in ophthalmology like Santen is very exciting. Such a strong partnership will greatly accelerate RPT’s ability to develop our product safely and effectively.”

This promising relationship highlights CIRM’s efforts to partner our clinical programs with outside investors to boost their chance of success. It also shows confidence in the future success of RPT’s stem cell-based therapy for AMD.

Retinitis Pigmentosa Trial Advances to Phase 2 and Receives RMAT Status

In May, the US Food and Drug Administration (FDA) approved jCyte’s RP trial for Regenerative Medicine Advanced Therapy (RMAT) status, which could pave the way for accelerated approval of this stem cell therapy for patients with RP.

RMAT is a new status established under the 21st Century Cures Act – a law enacted by Congress in December of 2016 to address the need for a more efficient regulatory approval process for stem cell therapies that can treat serious or life-threatening diseases. Trial sponsors of RMAT designated therapies can meet with the FDA earlier in the trial process and are eligible for priority review and accelerated approval.

jCyte’s RMAT status is well deserved. Their Phase 1 trial was successful, proving the treatment was safe and well-tolerated in patients. More importantly, some of the patients revealed that their sight has improved following their stem cell transplant. We’ve shared the inspiring stories of two patients, Rosie Barrero and Kristin Macdonald, previously on the Stem Cellar.

Rosie Barrero

Kristin MacDonald

Both Rosie and Kristin were enrolled in the Phase 1 trial and received an injection of retinal progenitor cells in a single eye. Rosie said that she went from complete darkness to being able to see shapes, colors, and the faces of her family and friends. Kristin was the first patient treated in jCyte’s trial, and she said she is now more sensitive to light and can see shapes well enough to put on her own makeup.

Encouraged by these positive results, jCyte launched its Phase 2 trial in April with funding from CIRM. They will test the same stem cell therapy in a larger group of 70 patients and monitor their progress over the next year.

Progress to a Cure for Blindness

We know very well that scientific progress takes time, and unfortunately we don’t know when there will be a cure for blindness. However, with the advances that these two CIRM-funded trials have made in the past year, our confidence that these stem cell treatments will one day benefit patients with RP and AMD is growing.

I’ll leave you with an inspiring video of Rosie Barrero about her experience with RP and how participating in jCytes trial has changed her life. Her story is an important reminder of why CIRM exists and why supporting stem cell research in particular, and research in general, is vital for the future health of patients.


Related Links: