A cardiac love triangle: how transcription factors interact to make a heart

 Here’s a heartfelt science story for all those Valentine’s day fans out there. Scientists from the Gladstone Institutes have identified how a group of transcription factors interact during embryonic development to make a healthy heart. Their work will increase our biological understanding of how the heart is formed and could produce new methods for treating cardiovascular disease.

The study, published today in the journal Cell, describes a tumultuous love story between cardiac transcription factors. Transcription factors are proteins that orchestrate gene expression. They have the power to turn genes on or off by binding to specific DNA sequences and recruiting other proteins that will eventually turn the information encoded in that gene into a functional protein.

Every organ has its own special group of transcription factors that coordinate the gene expression required for that organ’s development. Often times, transcription factors within a group directly interact with each other and work together to conduct a specific sequence of events. These interactions are essential for making healthy tissues and organs, but scientists don’t always understand how these interactions work.

For the heart, scientists have already identified a group of transcription factors essential for cardiac development, and genetic mutations in any of these factors can impair heart formation and cause heart defects in newborns. What’s not known, however, are the details on how some of these cardiac transcription factors interact to get their job done.

A cardiac love triangle

In the Gladstone study, the scientists focused on how three key cardiac transcription factors – NKX2.5, TBX5, and GATA4 – interact during heart development. They first proved that these transcription factors are essential for the formation of the heart in mouse embryos. When they eliminated the presence of one of the three factors from the developing mouse embryo, they observed abnormal heart development and heart defects. When they removed two factors (NKX2.5 and TBX5), the results were even worse – the heart wasn’t able to form and none of the embryos survived.

Normal heart muscle cells, courtesy Kyoto University

Normal cardiomyocytes or heart cells, courtesy Kyoto University

Next, they studied how these transcription factors interact to coordinate gene expression in heart cells called cardiomyocytes made from mouse embryonic stem cells that lacked either NKX2.5, TBX5, or both of these factors. Compared to normal heart cells, cardiomyocytes that lacked one or both of these two transcription factors started beating at inappropriate times – either earlier or later than the normal heart cells.

Taking a closer look, the scientists discovered that TBX5, NKX2.5 and GATA4 all hangout in the same areas of the genome in embryonic stem cells that are transitioning into cardiomyocytes. In fact, each individual transcription factor required the presence of the others to bind their DNA targets. If one of these factors was missing and the love triangle was broken, the remaining transcription factors became confused and bound random DNA sequences in the genome, causing a mess by turning on genes that shouldn’t be on.

First author on the study, Luis Luna-Zurita, explained the importance of maintaining this cardiac love triangle in a Gladstone Press Release:

Luis Luna-Zurita, Gladstone Institute

Luis Luna-Zurita, Gladstone Institute

“Transcription factors have to stick together, or else the other one goes and gets into trouble. Not only are these transcription factors vital for turning on certain genes, but their interaction is important to keep each other from going to the wrong place and turning on a set of genes that doesn’t belong in a heart cell.”

Crystal structure tells all

Protein crystal structure of NKX2.5 and TBX5 bound to DNA.

Protein crystal structure of NKX2.5 and TBX5 bound to DNA. (Luna-Zurita et al. 2016)

The last part of the study proved that two of these factors, NKX2.5 and TBX5, directly interact and physically touch each other when they bind their DNA targets. In collaboration with a group from the European Molecular Biology Laboratory (EMBL) in Germany, they developed protein crystal structures to model the molecular structure of these transcription factors when they bind DNA.

Co-author and EMBL scientist Christoph Muller explained his findings:

“The crystal structure critically shows the interaction between two of the transcription factors and how they influence one another’s binding to a specific stretch of DNA. Our detailed structural analysis revealed a direct physical connection between TBX5 and NKX2-5 and demonstrated that DNA plays an active role in mediating the interaction between the two proteins.”

Big picture

While this study falls in the discovery research category, its findings increase our understanding of the steps required to make a healthy heart and sheds light on what goes wrong in patients or newborns with heart disease.

Senior author on the paper and Gladstone Professor Benoit Bruneau explained the biomedical applications of their study for treating human disease:

DSC_0281_2

Benoit Bruneau, Gladstone Institute

“Gene mutations that cause congenital heart disease lower the levels of these transcription factors by half, and we’ve shown that the dosage of these factors determines which genes are turned on or off in a cell. Other genetic variants that cause heart defects like arrhythmias also affect the function of these factors. Therefore, the better we understand these transcription factors, the closer we’ll come to a treatment for heart disease. Our colleagues at Gladstone are using this knowledge to search for small molecules that can affect gene regulation and reverse some of the problems caused by the loss of these transcription factors.”

 

I think it’s worth mentioning that these studies were done using mouse embryos and mouse embryonic stem cells. Future work should be done to determine whether this cardiac love triangle and the same transcription factor interactions exist in human heart cells.


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How you derive embryonic stem cells matters

A scientist named James Thompson was the first to successfully culture human embryonic stem cells in 1998. He didn’t know it then, but his technique isolated a specific type of embryonic stem cell (ESC) that had a “primed pluripotent state”.

There are actually two phases of pluripotency: naïve and primed. Naïve ESCs occur a step earlier in embryonic development (during the beginning of the blastocyst stage), and the naïve state can be thought of as the ground state of pluripotency. Primed ESCs on the other hand are more mature and while they can still become every cell type in the body, they are somewhat less flexible compared to naïve ESCs. If you want to learn more about naïve and primed ESCs, you can refer to this scientific review.

Scientists have developed methods to derive both naïve and primed human ESCs in culture and are attempting to use these cells for biomedical applications. However, a recent CIRM-funded study published in Cell Stem Cell, calls into question the quality of ESCs produced using these culturing methods and could change how lab-derived stem cells are used for stem cell transplant therapies and regenerative medicine.

Primed human embryonic stem cells (purple) identified by a green stem cell surface marker. (Image courtesy of UCLA)

Primed human embryonic stem cells (purple) identified by a green stem cell surface marker. (Image courtesy of UCLA)

Culturing methods erase stem cell memory

UCLA scientists discovered that some of the culturing methods used to propagate naïve ESCs actually erase important biochemical signatures that are essential for maintaining ESCs in a naïve state and for passing down genetic information from the embryo to the developing fetus.

When they studied naïve ESCs in culture, they focused on a naturally occurring process called DNA methylation. It controls which genes are active and which are silenced by adding chemical tags to certain stretches of DNA called promoters, which are responsible for turning genes on or off. This process is critical for normal development and keeping cells functional and healthy in adults.

UCLA scientists compared the DNA methylation state of the mature human blastocyst – the early-stage embryo and where naïve ESCs come from – to the methylation state of naïve ESCs generated in culture. They found that the methylation patterns in the blastocyst six days after fertilization were the same as the patterns found in the egg that it developed from. This discovery is contrary to previous beliefs that the DNA methylation patterns in eggs are lost a few hours after fertilization.

Amander Clark, the study’s lead author and UCLA professor explained in a UCLA news release:

Amander+Clark+headshot_68295d00-2717-4d5c-99f3-f791e6b6ebcf-prv

Amandar Clark, UCLA

“We know that the six days after fertilization is a very critical time in human development, with many changes happening within that period. It’s not clear yet why the blastocyst retains methylation during this time period or what purpose it serves, but this finding opens up new areas of investigation into how methylation patterns built in the egg affect embryo quality and the birth of healthy children.”

The group also discovered cultured naïve ESCs lack these important DNA methylation patterns seen in early-stage blastocysts. Current methods to derive naïve ESCs wipe their memory leaving them in an unstable state. This is an issue for researchers because some prefer the use of naïve ESCs over primed ESCs for their studies because naïve ESCs have more potential for experimentation.

“In the past three years, naïve stem cells have been touted as potentially superior to primed cells,” Clark said. “But our data show that the naïve method for creating stem cells results in cells that have problems, including the loss of methylation from important places in DNA. Therefore, until we have a way to create more stable naïve embryonic stem cells, the embryonic stem cells created for the purposes of regenerative medicine should be in a primed state in order to create the highest-quality cells for differentiation.”

How you derive embryonic stem cells matters

Now that this culturing problem has been identified, the UCLA group plans to develop new and improved methods for generating naïve ESCs in culture such that they retain their DNA methylation patterns and are more stable.

The hope from this research is that scientists will be able to produce stem cells that more closely resemble their counterparts in the developing human embryo and will be better suited for stem cell therapies and regenerative medicine applications.


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A Tale of Two Stem Cell Treatments for Growing New Bones

Got Milk?

GotmilkIf you grew up during the 90’s, you most certainly will remember the famous “Got Milk?” advertising campaign to boost milk consumption. The plug was that milk was an invaluable source of calcium, a mineral that’s essential for growing strong bones. Drinking three glasses of the white stuff a day, supposedly would help deter osteoporosis, or the weakening and loss of bone with old age.

Research has proven that calcium is essential for growing and maintaining healthy bones. But milk isn’t the only source of calcium in the human diet, and a diet rich in calcium alone won’t prevent everyone from experiencing some amount of bone loss as they grow older. It also won’t help patients who suffer from bone skeletal defects grow new bone.

So whatever are we to do about bone loss and bone abnormalities? Here, we tell the “Tale of two stem cell treatments” where scientists tackle these problems using stem cell-derived therapies.

Protein Combo Boosts Bone Growth

Osteoporosis. (Image source)

Osteoporosis. (Image source)

Our first story comes from a CIRM-funded team of UCLA scientists. This team is interested in developing a better therapy to treat bone defects and osteoporosis. The current treatment for bone loss is an FDA-approved bone regenerating therapy involving the protein BMP-2 (bone morphogenetic protein-2). The problem with BMP-2 is that it can cause serious side effects when given in high doses. Two of the major ones are abnormal bone growth and also making stem cells turn into fat cells as well as bone cells.

The UCLA group attempted to improve the BMP-2 treatment by adding a second protein called NELL-1 (which they knew was good at stimulating bone growth from previous studies).  The combination of BMP-2 and NELL-1 resulted in bone growth and also prevented stem cells from making fat cells.

Upon further exploration, they found that NELL-1 acts as a signaling switch that controls whether a stem cell becomes a bone cell or a fat cell. Thus, with NELL-1 present, BMP-2 can only turn stem cells into bone cells.

Kang Ting, a lead author on the study, explained the significance of their new strategy to improve bone regeneration in a UCLA press release:

Kang Ting, UCLA

Kang Ting, UCLA

“Before this study, large bone defects in patients were difficult to treat with BMP2 or other existing products available to surgeons. The combination of NELL-1 and BMP2 resulted in improved safety and efficacy of bone regeneration in animal models — and may, one day, offer patients significantly better bone healing.”

Chia Soo, another lead author on the study, emphasized the importance of using NELL-1 in combination with BMP-2:

“In contrast to BMP2, the novel ability of NELL-1 to stimulate bone growth and repress the formation of fat may highlight new treatment approaches for osteoporosis and other therapies for bone loss.”

Stem cells that could fix deformed skulls

Our second story comes from a group at the University of Rochester. Their goal is to repair bones in the face and skull of patients suffering from congenital deformities, or damage due to injury or cancer surgery.

In a report published in Nature Communications, the scientists identified a population of skeletal stem cells that orchestrate the formation of the skull and can promote craniofacial bone repair in mice.

They identified this special population of skeletal stem cells by their expression of a protein called Axin2. Genetic mutations in the Axin2 gene can cause a birth defect called craniosynostosis. This condition causes the bone plates of a baby’s skull to fuse too early, causing skull deformities and impaired brain development.

1651177064_WeiHsu-stem cell photo_4487_275x200

Axin2 stem cells shown in red and blue generated new bones cells after transplantation.

According to a news release from the University of Rochester, the group’s “latest evidence shows that stem cells central to skull formation are contained within Axin2 cell populations, comprising about 1 percent—and that the lab tests used to uncover the skeletal stem cells might also be useful to find bone diseases caused by stem cell abnormalities.”

Additionally, senior author on the study, Wei Hsu, “believes his findings contributee to an emerging field involving tissue engineering that uses stem cells and other materials to invent superior ways to replace damaged craniofacial bones in humans due to congenital disease, trauma, or cancer surgery.”

Two different studies, one common goal

Both studies have a common goal: to repair or regenerate bone to treat bone loss, damage, or deformities. I can’t help but wonder whether these different strategies could be combined in a way to that would bring more benefit to the patient than using either strategy alone.

Could we use BMP-2 and NELL-1 treatment along with Axin2 skeletal stem cells to treat craniosynostosis or repair damaged skulls? Or could we identify new stem cell populations in bone that would help patients suffering from osteoporosis?

I’m sure scientists will answer these questions sooner rather than later, and when they do, you’ll be sure to read about it on the Stem Cellar!


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If you want to accelerate stem cell therapies then create an Accelerating Center

Buckle up

Buckle up, we’re about to Accelerate

“You can’t teach fish to fly,” is one of the phrases that our CIRM President & CEO, Randy Mills, likes to throw out when asked why we needed to create new centers to help researchers move their most promising therapies out of the lab and into clinical trials.

His point is that many researchers are terrific at research but not so great at the form filling and other process-oriented skills needed to get approval from the Food and Drug Administration (FDA) for a clinical trial.

So instead of asking them to learn how to do all those things, why don’t we, CIRM, create a system that will do it for them? And that’s where we came up with the idea for the Accelerating Center (we’re also creating a Translating Center – that’s a topic for a future blog but if you can’t wait to find out the juicy details you can find them here.)

The Accelerating Center will be a clinical research organization that provides regulatory, operational and other support services to researchers and companies hoping to get their stem cell therapies into a clinical trial. The goal is to match the scientific skills of researchers with the regulatory and procedural skills of the Accelerating Center to move these projects through the review process as quickly as possible.

But it doesn’t end there. Once a project has been given the green light by the FDA, the Accelerating Center will help with actually setting up and running their clinical trial, and helping them with data management to ensure they get high quality data from the trial. Again these skills are essential to run a good clinical trial but things researchers may not have learned about when getting a PhD.

We just issued what we call an RFA (Request for Applications)  for people interested in partnering with us to help create the Accelerating Center. To kick-start the process we are awarding up to $15 million for five years to create the Center, which will be based in California.

To begin with, the Accelerating Center will focus on supporting CIRM-funded stem cell projects. But the goal is to eventually extend that support to other stem cell programs.

Now, to be honest, there’s an element of self-interest in all this. We have a goal under our new Strategic Plan of funding 50 new clinical trials over the next five years. Right now, getting a stem cell-related project approved is a slow and challenging process. We think the Accelerating Center is one tool to help us change that and give the most promising projects the support they need to get out of the lab and into people.

There’s a lot more we want to do to help speed up the approval process as well, including working with the FDA to create a new, streamlined regulatory process, one that is faster and easier to navigate. But that may take some time. So in the meantime, the Accelerating Center will help “fish” to do what they do best, swim, and we’ll take care of the flying for them.

 

 

 

CREATE-ing tools that deliver genes past the blood-brain barrier

Your brain has a natural defense that protects it from infection and harm, it’s called the blood-brain barrier (BBB). The BBB is a selectively permeable layer of tightly packed cells that separates the blood in your circulatory system from your brain. Only certain nutrients, hormones, and molecules can pass through the BBB into the brain, while harmful chemicals and infection-causing bacteria are stopped at the border.

This ultimate defense barrier has its downsides though. It’s estimated that 98% of potential drugs that could treat brain diseases cannot pass through the BBB. Only some drug compounds that are very small in size or are fat-soluble can get through. Clearly, getting drugs and therapies past the BBB is a huge conundrum that remains to be solved.

Penetrating the Impenetrable

However, a CIRM-funded study published today in Nature Biotechnology has developed a delivery tool that can bypass the BBB and deliver genes into the brain. Scientists from Caltech and Stanford University used an innocuous virus called an adeno-associated virus (AAV) to transport genetic material through the BBB into brain cells.

Viral delivery is a common method to target and deliver genes or drugs to specific tissues or cells in the body. But with the brain and its impenetrable barrier, scientists are forced to surgically inject the virus into specific areas of the brain, which limits the areas of the brain that get treatment, not to mention the very invasive and potentially damaging nature of the surgery itself. For diseases that affect multiple areas in the brain, like Huntington’s and Alzheimer’s disease, direct injection methods are not likely to be effective. Thus, a virus that can slip past the BBB and reach all parts of the brain would be an idea tool for delivering drugs and therapies.

And that’s just what this new study accomplished. Scientists developed a method for generating modified AAVs that can be injected into the circulatory system of mice, pass through the BBB, and deliver genetic material into the brain.

They devised a viral selection assay called CREATE (which stands for Cre Recombinase-based AAV Targeted Evolution). Using CREATE, they tested millions of AAVs that all had slight differences in the genetic composition of their capsid, or the protein shell of the virus that protects the viruses’ genetic material. They tested these modified viruses in mice to see which ones were able to cross the BBB and deliver genes to support cells in the brain called astrocytes. For more details on how the science of CREATE works, you can read an eloquent summary in the Caltech press release.

A Virus that Makes Your Brain Glow Green

After optimizing their viral selection assay, the scientists were able to identify one AAV in particular, AAV-PHP.B, that was exceptionally good at getting past the BBB and targeting astrocytes in the mouse brain.

Lead author on the study, Ben Deverman, explained: “By figuring out a way to get genes across the blood-brain barrier, we are able to deliver them throughout the adult brain with high efficiency.”

They used AAV-PHP.B and AAV9 (which they knew could pass the BBB and infect brain cells) to transport a gene that codes for green fluorescent protein (GFP) into the mouse brain. After injecting mice with both viruses containing GFP, they saw that both viruses were able to make most of the cells in the brain glow green, confirming that they successfully delivered the GFP gene. When they compared the potency of AAV-PHP.B to the AAV9 virus, they saw that AAV-PHP.B was 40 times more efficient in delivering genes to the brain and spinal cord.

sing a new selection method, Caltech researchers have evolved the protein shell of a harmless virus, AAV9, so that it can more efficiently cross the blood brain barrier and deliver genes, such as the green fluorescent protein (GFP), to cells throughout the central nervous system. Here, GFP expression in naturally occurring AAV9 (left) can be seen distributed sparsely throughout the brain. The modified vector, AAV-PHP.B (right), provides more efficient GFP expression. Credit: Ben Deverman and the Gradinaru laboratory/Caltech - See more at: http://www.caltech.edu/news/delivering-genes-across-blood-brain-barrier-49679#sthash.BDu7OfC8.dpuf

Newly “CREATEd” AAV-PHP.B (right) is better at delivering the GFP gene to the brain than AAV9 (left). Credit: Ben Deverman.

“What provides most of AAV-PHP.B’s benefit is its increased ability to get through the vasculature into the brain,” said Ben Deverman. “Once there, many AAVs, including AAV9 are quite good at delivering genes to neurons and glia.”

Senior author on the study, Viviana Gradinaru at Caltech, elaborated: “We could see that AAV-PHP.B was expressed throughout the adult central nervous system with high efficiency in most cell types.”

Not only that, but using a neat technique called PARS CLARITY that Gradinaru developed in her lab, which makes tissues and organs transparent, the scientists were able to see the full reach of the AAV-PHP.B virus. They saw green cells in other organs and in the peripheral nerves, thus showing that AAV-PHP.B works in other parts of the body, not just the brain.

But just because AAV-PHP.B is effective in mice doesn’t mean it works well in humans. To address this question, the authors tested AAV-PHP.B in human neurons and astrocytes derived from human induced pluripotent stem cells (iPS cells). Sergiu Pasca, a collaborator from Stanford and author on the study, told the Stem Cellar:

Sergiu Pasca

Sergiu Pasca

“We have also tested the new AAV variant (AAV-PHP.B) in a human 3D cerebral cortex model developed from human iPS cells and have shown that it transduces human neurons and astrocytes more efficiently than does AAV9 demonstrating the potential for biomedical applications.”

An easier way to deliver genes across the BBB

This study provides a new way to cross the BBB and deliver genes and potential therapies that could treat a laundry list of degenerative brain diseases.

This is only the beginning for this new technology. According to the Caltech press release, the study’s authors have future plans for the AAV-PHP.B virus:

“The researchers hope to begin testing AAV-PHP.B’s ability to deliver potentially therapeutic genes in disease models. They are also working to further evolve the virus to make even better performing variants and to produce variants that target certain cell types with more specificity.”


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Super stem cell exhibit opens in San Diego

Stem cell exhibit

The best science museums are like playgrounds. They allow you to wander around, reading, watching and learning and being amazed as you go. It’s not just a feast for the mind; it’s also fun for the hands.  You get to interact with and experience science, pushing buttons, pulling levers, watching balls drop and electricity spark.

The best science museums bring out the kid in all of us.

This Saturday a really great science museum is going to be host to a really great exhibition. The Reuben H. Fleet Science Center in San Diego is the first stop on a California tour for “Super Cells: The Power of Stem Cells”. The exhibit is coming here fresh from a successful tour of Canada and the UK.

The exhibit is a “hands-on” educational display that demonstrates the importance and the power of stem cells, calling them “our body’s master cells.” It uses animations, touch-screen displays, videos and stunning images to engage the eyes and delight the brain.

stem cell exhibit 2Each of the four sections focuses on a different aspect of stem cell research, from basic explanations about what a stem cell is, to how they change and become all the different cells in our body. It has a mini laboratory so visitors can see how research is done; it even has a “treatment” game where you get to implant and grow cells in the eye, to see if you can restore sight to someone who is blind.

 

In a news release the Fleet Science Center celebrated the role that stem cells play in our lives:

“Stem cells are important because each of us is the result of only a handful of tiny stem cells that multiply to produce the 200 different types of specialized cells that exist in our body. Our stem cells continue to be active our whole lives to keep us healthy. Without them we couldn’t survive for more than three hours!”

It is, in short, really fun and really cool.

Of course we might be a tad biased here as we helped produce and develop the exhibit in collaboration with the Sherbrooke Museum of Science and Nature in Canada, the Canadian Stem Cell Network, the Centre for Commercialization of Regenerative Medicine in Canada; the Cell Therapy Catapult in the UK, and EuroStemCell.

stem cell exhibit 3

The exhibit is tri-lingual (English, Spanish and French) because our goal was to create a multi-lingual global public education program. San Diego was an obvious choice for the first stop on the California tour (with LA and the Bay Area to follow) because it is one of the leading stem cell research hubs in the U.S., and a region where CIRM has invested almost $380 million over the last ten years.

As our CIRM Board Chair, Jonathan Thomas, said:

“One of our goals at CIRM is to help spread awareness for the importance of stem cell research. San Diego is an epicenter of stem cell science and having this exhibition displayed at the Reuben H. Fleet Science Center is a wonderful opportunity to engage curious science learners of all ages.”

The Super Cells exhibit runs from January 23 to May 1, 2016, in the Main Gallery of the Reuben H. Fleet Science Center. The exhibition is included with the cost of Fleet admission.

For more information, visit the Reuben H. Fleet Science Center website.

Protective cell therapy could mean insulin independence for diabetic patients

This has already been a productive year for diabetes research. Earlier this month, scientists from UCSF and the Gladstone Institutes successfully made functional human pancreatic beta cells from skin, providing a new and robust method for generating large quantities of cells to replace those lost in patients suffering from type 1 diabetes.

Today marks another breakthrough in the development of stem cell therapies for diabetes. Scientists from MIT and the Harvard Stem Cell Institute published a new method in Nature Medicine that encapsulates and protects stem cell-derived pancreatic beta cells in a way that prevents them from being attacked by the immune system after transplantation.

Protecting transplanted cells from the immune system

Stem cell therapy holds promise for diabetes for a number of reasons. First, scientists now have the ability to generate large numbers of insulin producing pancreatic beta cells from human skin and stem cells. This obviates the need for donor beta cells, which are always in short supply and high demand. Second, there’s the issue of the immune system. Transplanting beta cells from a donor into a patient will trigger an immunological reaction, which can only be abated by a lifetime regimen of immunosuppressive drugs.

One way that scientists have addressed the issue of immune rejection is to transplant stem cell-derived beta cells in a protected capsule. A CIRM-funded company called ViaCyte has developed a medical device that acts like a replacement pancreas but is surgically implanted under the skin. It contains human beta cells derived from embryonic stem cells and has a membrane barrier that allows only certain molecules to pass in and out of the device. This way, the foreign pancreatic cells are shielded from the immune system, but they can still respond to changing blood sugar levels in the patient by secreting insulin into the blood stream.

Another way that scientists trick the immune system in diabetes patients uses a similar strategy but instead of a medical device that protects a large population of cells, they encapsulate individual islets (clusters of beta cells) using biomaterials.

However, previous attempts using a biomaterial called alginate to encapsulate islets caused an immune response in the form of fibrosis, or scar tissue, and cell death. Additionally, transplanted alginate microspheres were only able to achieve glycemic control, or control of blood sugar levels, temporarily in animal models.

In the Nature Medicine study, the scientists developed a new method for beta cell encapsulation where they used a chemically modified version of the alginate microspheres – triazole-thiomorpholine dioxide (TMTD) – that didn’t cause an immune reaction and was able to maintain glycemic control in mice that had diabetes.

New protective method makes diabetic mice insulin independent

The scientists tested the conventional alginate microspheres and the modified TMTD-alginate microspheres containing embryonic stem cell-derived human beta islets in diabetic mice.

Encapsulated beta islets were transplanted into diabetic mice. (Nature Medicine)

Encapsulated beta islets were transplanted into diabetic mice. (Nature Medicine)

They found that the conventional smaller alginate microspheres caused fibrosis while larger TMTD-alginate microspheres did not. They observed that the modified TMTD-alginate microspheres were able to achieve glycemic control for over 70 days after transplantation while conventional microspheres didn’t perform as well.

The scientists also looked at the immune response to both types of alginate spheres. They saw lower numbers of immune cells and less fibrosis surrounding the transplanted TMTD microspheres compared to the conventional microspheres.

The final studies were the icing on the cake. The asked whether the modified TMTD microspheres were able to maintain long-term glycemic control or insulin independence, which would mean sustaining blood glucose levels in diabetic mice for over 100 days. They studied diabetic mice that received TMTD microspheres for 174 days. At 150 days, they performed a glucose test and saw that the diabetic mice were just as good at regulating glucose levels as normal mice. Furthermore, after 6 months, these mice showed no build up of fibrotic tissue, indicating that the modified microspheres weren’t causing an immune response and these mice didn’t need immunosuppressive drugs.

What the experts had to say…

This study was picked up by STATnews, which also mentioned another related study published in Nature Biotechnology that tested various alginate derivatives in rodent and monkey models of diabetes.

Julia Greenstein, vice president of discovery research at JDRF, discussed the implications of both studies with STATnews:

“This is really the first demonstration of the ability of these novel materials in combination with a stem-cell derived beta cell to reverse diabetes in an animal model. Our goal is to bring that kind of biological cure across the spectrum of type 1 diabetes.”

First author on both studies, Arturo Vegas, also gave his thoughts and discussed future applications:

Arturo Vegas

Arturo Vegas

“From very early on, we were getting great success. Everything kind of fell into place. You saw less foreign body response. The human beta cells survived exquisitely well. I think we’ve advanced the ball pretty far, almost as far you could get in an academic environment. The talk is shifting toward doing something clinically.”

According to STATnews, Vegas and his team are working on tests now in monkey models. “Vegas said that if the primate studies are successful, the next step will be developing a therapy to be used in people.”


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Training the Next Generation of Stem Cell Scientists

Nobel prize winners don’t come out of thin air, they were all young, impressionable kids at one point in time.  If you ask any award-winning scientists how they got into science research, many of them would likely tell you about an inspiring teacher, an encouraging parent, or a hands-on research opportunity that inspired or helped them to pursue a scientific career.

Not every student is lucky enough to have one of these experiences, and many students, especially those from low income families, might never be exposed to good science or have the opportunity to pursue a career as a scientist.

CIRM is changing this for students in California by committing a significant portion of its funds to educating and training future stem cells scientists.

Yesterday, the Board approved over $42 million to fund two of CIRM’s educational programs, the Bridges to Stem Cell Research and Therapy Awards (Bridges) and the Summer Program to Accelerate Regenerative Medicine Knowledge (SPARK).

Bridging the Stem Cell Gap

The Bridges program supports undergraduate and master’s level students by providing paid research internships at California universities or colleges that don’t have a major stem cell research program. This program has evolved over the past seven years since it began, and now includes training and education courses in stem cell research, and direct patient engagement and outreach activities within California’s diverse communities.

CIRM’s president, Randy Mills explained in a press release:

Randy Mills, Stem Cell Agency President & CEO

Randy Mills, CIRM President & CEO

“The goal of the Bridges program is to prepare undergraduate and Master’s level students in California for a successful career in stem cell research. That’s not just a matter of giving them money, but also of giving them good mentors who can help train and guide them, of giving them meaningful engagement with patients and patient advocates, so they have a clear vision of the impact the work they are doing can have on people’s lives.”

Chairman of the CIRM Board, Jonathan Thomas, added:

Jonathan Thomas

Jonathan Thomas, Chairman of the CIRM Board

“The Bridges program has been incredibly effective in giving young people, often from disadvantaged backgrounds, a shot at a career in science. Of the 700 students who have completed the program, 95 percent are either working in a lab, enrolled in school or applying to graduate school. Without the Bridges program this kind of career might have been out of reach for many of these students.”

The CIRM Board voted to approve $40.13 million for the Bridges program, which will fund 14 programs at California state universities and city colleges. Each program will be able to support ten students for five years.

SPARKing Interest in Stem Cells

The SPARK program supports summer research internships for high school students that represent the diversity of the state’s population. It evolved from an earlier educational program called Creativity, and now emphasizes community outreach, direct patient engagement activities, and social media training along with training in stem cell research techniques.

“SPARK is all about helping cultivate high school students who are interested in science, and showing them it’s possible to have a career doing something they love,” said Randy Mills.

The Board approved $2.31 million for the SPARK program, which will provide California institutions funding support for five to ten students each year. Seven programs received funding including the Children’s Hospital Oakland Research Institute, UC San Francisco, UC Davis, Cedars-Sinai, City of Hope, USC and Stanford.

2015 Creativity Program students (now called SPARK).

2015 Creativity Program students (now called SPARK).

Training the Next Generation

For years, national leaders, including President Obama, have warned that without skilled, experienced researchers, the U.S. is in danger of losing its global competitiveness in science. But cuts in federal funding for research mean this is a particularly challenging time to begin a scientific career.

Our goal with the Bridges and SPARK programs is to address both these issues and support young scientists as they get the experience they need to launch their careers.


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New Stem Cell Treatment for ALS May Slow Disease Progression

Exciting news was published this week that will give patients suffering from ALS, also known as Lou Gehrig’s disease, something to cheer about. The journal JAMA Neurology reported that a new stem cell treatment was successful in slowing disease progression in a small group of ALS patients in a Phase 2 clinical trial.

This is big news for a fatal, incurable disease that is well known for its progressive, degenerating effects on nerve cells in the brain and spinal cord. We’ve written about ALS a lot in the Stem Cellar, so if you want more background on the disease, read our “Progress to a Cure for ALS” blog.

A patient’s own stem cells can help

The stem cell therapy involves extracting mesenchymal stem cells from the bone marrow of ALS patients. These stem cells are then manipulated in culture into cells that secrete a growth factor called NeuroTrophic Factor (NTF), which helps keep nerve cells in the brain and spinal cord healthy and alive. The NTF-secreting stem cells (called NurOwn cells) are then transplanted back into the same ALS patient (making this an autologous stem cell therapy) by injection into either the spinal fluid or the muscles.

logoThe NurOwn method was developed by BrainStorm Cell Therapeutics, a biotech company based in the US and Israel. Clinical trials to test the safety and efficacy of NurOwn stem cells began in 2011 at the Hadassah Medical Organization (HMO). So far, 26 patients have participated in the trials both in the US and in Israel.

According to the JAMA publication, patients were monitored 3 months before and 6 months after they received stem cell transplants and 6 months after. Twelve of the 26 patients participated in an early stage of the trial (phase 1/2) to test the safety and tolerability of the stem cell therapy. The other 14 patients participated in a later stage (phase 2a), dose-escalating study where their modified stem cells were injected into both their spinal fluid and muscles. Following the treatment, the scientists looked at the safety profile of the transplanted stem cells and for signs of clinical improvement in patients such as their ease of breathing or ability to control their muscle movement.

Stem cell treatment is effective in most ALS patients

Results from the clinical trial showed that a majority of the patients benefitted from the NurOwn stem cell therapy. HMO Principle scientist and senior author on the study, Dr. Dimitrios Karussis, explained:

Dr. Dimitrios Karussis (Image credit: Israel21c)

Dimitrios Karussis (Israel21c)

“The results are very encouraging.  Close to 90% of patients who were injected intrathecally through the spinal cord fluid were regarded as responders to the treatment either in terms of their respiratory function or their motor disability.  Almost all of the patients injected in this way showed less progression and some even improved in their respiratory functions or their motor functions.”

A PRNewswire press release covering this study called the stem cell therapy the “first-of-its-kind treatment for treating neurodegenerative diseases.”

Not a cure just yet

This stem cell therapy will need to be tested in more patients before the it can be determined truly effective in slowing progression of ALS. And Dr. Karussis was quick to note that the NurOwn stem cell therapy isn’t a cure for ALS, but rather an early-stage therapy that will provide significant benefit to patients by slowing disease progression.

“I am optimistic that within the foreseeable future, we may provide a treatment to ALS patients that can slow down or stop the progression. I believe we are in the early stages of something new and revolutionary with this harvested stem cell infusion therapy.  While this is absolutely by no means a cure, it is the first step in a long process in that direction.  I see this treatment as being potentially one of the major future tools to treat degenerative diseases of the brain and spinal cord, in general.”

Other stem cell treatments for ALS in the works

A single stem cell therapy that could treat multiple neurodegenerative diseases would be extremely valuable to patients and doctors. However, it’s not clear that the “one ring to rule them all” scenario (couldn’t help making a Lord of the Rings reference) will play out well for all diseases that affect the brain and spinal cord. Luckily, Dr. Karussis and Brainstem Cell Therapeutics are not the only ones pursuing stem cell therapies for ALS.

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

Clive Svendsen

CIRM is currently funding 21 studies (a total of $56.6 million) that use stem cells to either study ALS or to develop therapies to treat the disease. We wrote about one recent study by Clive Svendsen at Cedars Sinai which is using a combination of gene therapy and brain stem cells to deliver growth factors to protect nerve cells in the brain and spinal cord of ALS patients. Currently, Svendsen and his team are in the latter stages of research and hope to apply for FDA approval to test their therapy in patients in the near future. Svendsen told CIRM, “we will begin recruiting patients the first week we have approval.”


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What Went Down at ARM’s Regenerative Medicine State of the Industry

Every January, downtown San Francisco is taken over by a flock of investors, bankers, biotech companies, and scientists attending the annual JP Morgan Healthcare Conference. This meeting looks at the healthcare advancements over the past year and predicts the disease areas and technologies that will see the most progress and success in 2016.

According to some of the experts at the event, regenerative medicine and stem cell research are experiencing impressive, accelerated advancements, which has peaked the interest of investors, biotech, and pharmaceutical companies.

Because these are such fast paced fields, the Alliance for Regenerative Medicine (ARM) hosts the Annual Regenerative Medicine and Advanced Therapies State of the Industry Briefing during JP Morgan to discuss the recent progress and outlook for the industry in the coming year.

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What happened in 2015 and what’s next?

ARM’s  6th Annual Briefing was open to the public and drew over 300 people on Monday morning. The meeting opened with an industry update from Edward Lanphier, ARM Chairman and President/CEO of Sangamo BioSciences.  Then two panels featuring top leaders from biotech and pharmaceutical companies discussed the 2016 clinical data forecast and the promise of regenerative medicine and advanced therapies in oncology (cancer).

With an upbeat attitude, Lanphier gave an overview of clinical development progress in 2015, with 20 approved products worldwide and over 600 clinical trials both from academia and industry. More than 40% of these ongoing clinical trials are in cancer while approximately 12% are in heart disease/injury. These trials are not limited to Phase 1 either. In 2015, there were 376 in Phase 2 (compared to 200 in 2014) and 64 in Phase 3 (compared to 39 in 2014).

Edward Lanphier

Edward Lanphier

Two other areas Lanphier emphasized were CAR-T and other cell-based immunotherapies and gene therapy programs for rare diseases. He ended with 2015 statistics on clinical milestones in various disease and therapy programs, key company IPOs, the financial landscape, and predictions of major anticipated data from clinical trials in 2016.

It was a lot to take in, but this was definitely a good thing and a sign that the areas of regenerative medicine and advanced therapies are thriving. If you want more details, you can check out ARM’s State of the Industry presentation.

Major Theme: Data is King

The major theme that cropped up during the industry update and panel discussions was the importance of producing meaningful clinical data to get positive outcomes in regenerative medicine.

This was succinctly put by panelist Sven Kili, head of Gene Therapy Development at GlaxoSmithKline:

“I would say “Data is King”. A great idea is fantastic, passion is wonderful, and most companies will buy into a strong management team, but that only gets you so far. After that you need to have data, and you need to have a good plan for going forward.”

Kill added that there’s the need to work with the FDA to change the regulatory process, saying the FDA is, understandably, cautious about working with therapies that can alter a person’s genome permanently. However, he said there needs to be serious discussions with the FDA about how to speed up the process, to make it easier for the most promising projects to get approval.

Edward Lanphier also talked about the industry’s new focus on clinical data and the questions that arise when trying to advance regenerative medicine research into approved treatments and cures for patients:

“How do we communicate the value of curing blindness? How do we think about pricing that? What do we think about [drug] reimbursement?  For rare diseases, we aren’t trying to talk about acute treatments – we are talking about one-time, curative outcomes. And the value and benefit to patients in this is enormous. This is what we are trying to do, and on the cusp of, in terms of generating both approvable data and also the proof of concept data that then allows us to drive that next value inflection point in terms of financings.”

The Future Looks Good

After listening to the briefing, the future of regenerative medicine and advanced therapies certainly looks bright. As Jason Kolbert, head of Healthcare Research at the Maxim Group, said:

“This industry is now rapidly maturing and regenerative medicine and gene therapy have great things in store for the next decade.”

Usman Azam, Global Head of Cell and Gene Therapies at Novartis, had a similar outlook:

“We now are going from proof of concept to commercial availability of a disruptive innovation within seven years. If somebody had said that to me four years ago, I would have said, not possible. But that gives you a sense of how quickly this field is moving.”

Experts Panel

ARM Panel: 2016 Sector Forecast: Upcoming Clinical Data Events