CIRM invests $1.3 million to study stem cells in metabolic liver disease

Grikscheit

Dr. Tracy Grikscheit. Image courtesy of Children’s Hospital LA.

Metabolic liver disease, is an emerging public health concern in Western countries, but has largely been overshadowed by health issues such as cancer and diabetes. Chronic liver disease (of which metabolic liver disease is a significant contributor) however, is a significant public health concern, evidenced by its contribution to nearly 2 million deaths per year worldwide.

The primary treatment option for metabolic liver disease is a liver transplant. In fact, of the liver transplants performed every year, 14% are due to damage associated with metabolic disorders. With any organ transplant, however, such a procedure comes with drawbacks, the most frustrating of which is the need for patients to wait for an organ donor.

As transplants are not a reasonable or feasible option for many people, alternative treatment options are necessary.  Enter Dr. Tracy Grikscheit, a doctor-scientist at the Children’s Hospital Los Angeles, who hopes to make liver transplant a thing of the past for the millions of people who live with metabolic liver disease.

Dr. Grikscheit was awarded a $1.3 million grant to study how stem cells can be used to treat liver disease caused by metabolic disorders. In a press release, Dr. Grikscheit details the importance and practicality of using stem cells to treat liver disease:

“Liver-based metabolic diseases are the perfect starting point to apply cellular therapy to liver disorders. The only current therapy — a liver transplant — is costly and in short supply. Plus, it requires suppressing the patient’s immune system, which has long-term consequences.”

The project, termed UPLiFT for Universal Pluripotent Stem Cell Therapy, aims to use pluripotent stem cells (cells that can turn into any cell in the body) to correct liver associated disorders like Crigler-Najjar Syndrome. A genetic mutation in liver cells of these patients makes them unable to covert bilirubin (a byproduct of red blood cell degradation) to its non-toxic form. Dr. Grikscheit hopes to bypass the need for a liver transplant by giving these patients pluripotent stem cells that can become liver cells without the genetic mutation, and are able to convert bilirubin to its non-toxic form. The use of pluripotent stem cells would also potentially eliminate the need for lifelong immunosuppressive therapy

Dr. Grikscheit will use the CIRM grant to test safety and efficacy of the stem cell treatment in pre-clinical trials to determine the optimal cell dosage that will be both safe and relieve disease symptoms, as well as assessing any off-target effects of the treatment. She has previously received a grant from CIRM to study stem cell therapy options for digestive neuromuscular condition, which you can read about here.

 

Sequencing data helps us understand the genes involved in heart cell development

skin cells to beating heart

Human heart cells generated in the laboratory. Image courtesy of Nathan Palapant at the University of Queensland

Heart disease is the leading cause of death for both men and women in the United States and is estimated to be responsible for 31% of all deaths globally. This disease encompasses a wide variety of conditions that all effect how well your heart is able to pump blood to the rest of your body. One of the reasons that heart disease is so devastating is because, unlike many other organs in our bodies, heart tissue is not able to repair itself once it is damaged. Now scientists at the Institute for Molecular Bioscience at the University of Queensland and the Garvan Institute for Medical Research in Australia have conducted a tour de force study to exquisitely understand the genes involved in heart development.

The findings of the study are published in the journal Cell Stem Cell. in a press release, Dr. Nathan Palapant, one of the the lead authors, says this type of research could pay dividends for heart disease treatment because:

“We think the answers to heart repair almost certainly lie in understanding heart development. If we can get to grips with the complex choreography of how the heart builds itself in the first place, we’re well placed to find new approaches to helping it rebuild after damage.”

To determine which genes are involved in heart cell development, the investigators use a method called single cell RNA sequencing. This technique allowed them to measure how 17,000 genes (almost every gene that is active in the heart) were being turned on and off during various stages of heart cell development in 40,000 human pluripotent stem cells (stem cells that are capable of becoming any other cell type) experimentally induced to turn into heart cells.  This data set, the first of its kind, is a critical new resource for all scientists studying heart development and disease.

Interestingly, this study also addressed a commonly present, but rarely discussed issue with scientific studies: how applicable are results generated in vitro (in the lab) rather than the body, in the context of human health and disease? It is well known that heart cells generated in the lab do not have the exact same characteristics as mature heart cells found in our bodies, but the extent and precise nature of those discrepancies is not well understood. These scientists find that a gene called HOPX, which is one of earliest markers of heart cell development, is not always expressed when it should be during in vitro cardiac cell development, which, in turn, affects expression of other genes that are downstream of HOPX later on in development. Therefore, these scientists suggest that mis-expression of HOPX  might be one reason why in vitro heart cells express different genes and are distinct from heart cells in humans.

The scientists also learned that HOPX is responsible for controlling whether the developing heart cell moves past the “immature” dividing phase to the mature phase where cells grow bigger, but do not divide. This finding shows that this data set is powerful both for determining differences between laboratory grown cells versus mature human cells, but also provides critical biological information about heart cell development.

Joseph Powell, another lead author of this research, further explains how this work contributes to the important fundamentals of heart cell development:

“Each cell goes through its own series of complex, nuanced changes. They are all different, and changes in one cell affect the activity of other cells. By tracking those changes across the different stages of development, we can learn a huge amount about how different sub-types of heart cells are controlled, and how they work together to build the heart.”

If you’re into stem cell manufacturing, this is the conference for you!

GMP cells

Manufacturing stem cells: Photo courtesy of Pluristem

Fulfilling CIRM’s mission doesn’t just mean accelerating promising stem cell treatments to patients. It also involves accelerating the whole field of regenerative medicine, which involves not just research, but developing candidate treatments, manufacturing cell therapies, and testing these therapies in clinical trials.

Manufacturing and the pre-clinical safety evaluation of cell therapies are topics that don’t always receive a lot of attention, but they are essential and crucial steps in bringing cell therapies to market. Manufacturing cells that meet the strict standards for use in human trials is often a bottleneck where different methods of making pluripotent stem cells (PSCs) are used and standardization is not readily possible.

Abla-8Abla Creasey, Vice President of Therapeutics and Strategic Infrastructure at CIRM, notes:

“The field of stem cell research and regenerative medicine has matured to the point where there are over 900 clinical trials worldwide. It is critical to develop a system of effective regulation of how these stem cell treatments are developed and manufactured so patients can benefit from future treatments.”

To address this challenge, CIRM has teamed up the International Alliance for Biological Standardization to host the 4th Cell Therapy Conference on Manufacturing and Testing of Pluripotent Stem Cells on June 5-6th in Los Angeles, California.

WHAT

The aim of this conference is twofold. Speakers will discuss how product development programs can be moved forward in a way that will meet regulatory requirements, so treatments can be approved.

The conference will also focus on key unresolved issues that need to be addressed for the manufacturing and safety testing of pluripotent stem cell-based therapies and then make recommendations to inform the future national and international policies. The overall aim is to provide participants with a road map so new treatments can achieve the highest regulatory standards and be made available to patients around the world.

The agenda of the conference will cover four main topics:

  1. Learning from the current pluripotent space and the development of international standards
  2. Bioanalytics and comparability of therapeutic stem cells
  3. Tumorigenicity testing for therapeutic safety
  4. Pluripotent stem cell manufacturing, storage, and shipment Issues

Using this “big tent” approach, speakers will exchange knowledge, experience and expertise to develop consensus recommendations around stem cell manufacturing and testing.  New data in this area will be introduced at the conference for the first time, such as a multi-center study to identify and optimize manufacturing-compatible methods for cell therapy safety.

WHO

The conference will bring together leading experts from industry, academia, health services and therapeutic regulatory bodies around the world, including the US Food and Drug Administration, European Medicines Agency, Japan Pharmaceuticals and Medical Devices Agency, and World Health Organization.

CIRM and IABS encourage individuals and organizations actively pursuing the development of stem cell therapies to attend.

WHY

robert deansIf you’re interested, but not quite sold on this conference, take the word of these experts:
Robert Deans, Chief Technology Officer at BlueRock Therapeutics:

“I believe standardization will be an increasingly crucial element in securing commercial success for regenerative cell therapies.  This applies to all facets of development, from cell characterization and patent protection through safety testing of final product.  Most important is the adherence of players in this sector to harmonized standards and creation of a scientifically credible market to the capital community.”

martin-pera-profileProfessor Martin Pera of the Jackson Laboratory, who directs the International  Stem Cell Initiative Genetics and Epigenetics Study Group:

“Participants at this meeting will survey and discuss the state of the art in the development of definitive assays for assessing the safety of pluripotent stem cell based therapies, a critical issue for the future of the field.  Anyone active in cell therapy should attend this meeting to contribute to a dialogue that will impact on research directions and ultimately help to define best practice in this sector.”

When and Where

The conference will be held in Los Angeles Airport Marriott on June 5-6th, 2018. Registration is now open on the IABS website and you can take advantage of discounted early bird registration before April 24th.

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.”

Stem cell stories that caught our eye: turning on T cells; fixing our brains; progress and trends in stem cells; and one young man’s journey to recover from a devastating injury

Healthy_Human_T_Cell

A healthy T cell

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

Directing the creation of T cells. To paraphrase the GOP Presidential nominee, any sane person LOVES, LOVES LOVES their T cells, in a HUGE way, so HUGE. They scamper around the body getting rid of viruses and the tiny cancers we all have in us all the time. A CIRM-funded team at CalTech has worked out the steps our genetic machinery must take to make more of them, a first step in letting physicians turn up the action of our immune systems.

We have known for some time the identity of the genetic switch that is the last, critical step in turning blood stem cells into T cells, but nothing in our body is as simple as a single on-off event. The Caltech team isolated four genetic factors in the path leading to that main switch and, somewhat unsuspected, they found out those four steps had to be activated sequentially, not all at the same time. They discovered the path by engineering mouse cells so that the main T cell switch, Bcl11b, glows under a microscope when it is turned on.

“We identify the contributions of four regulators of Bcl11b, which are all needed for its activation but carry out surprisingly different functions in enabling the gene to be turned on,” said Ellen Rothenberg, the senior author in a university press release picked up by Innovations Report. “It’s interesting–the gene still needs the full quorum of transcription factors, but we now find that it also needs them to work in the right order.”

Video primer on stem cells in the brain.  In conjunction with an article in its August issue, Scientific American posted a video from the Brain Forum in Switzerland of Elena Cattaneo of the University of Milan explaining the basics of adult versus pluripotent stem cells, and in particular how we are thinking about using them to repair diseases in the brain.

The 20-minute talk gives a brief review of pioneers who “stood alone in unmarked territory.” She asks how can stem cells be so powerful; and answers by saying they have lots of secrets and those secrets are what stem cell scientist like her are working to unravel.  She notes stem cells have never seen a brain, but if you show them a few factors they can become specialized nerves. After discussing collaborations in Europe to grow replacement dopamine neurons for Parkinson’s disease, she went on to describe her own effort to do the same thing in Huntington’s disease, but in this case create the striatal nerves lost in that disease.

The video closes with a discussion of how basic stem cell research can answer evolutionary questions, in particular how genetic changes allowed higher organisms to develop more complex nervous systems.

kelley and kent

CIRM Science Officers Kelly Shepard and Kent Fitzgerald

A stem cell review that hits close to home.  IEEE Pulse, a publication for scientists who mix engineering and medicine and biology, had one of their reporters interview two of our colleagues on CIRM’s science team. They asked senior science officers Kelly Shepard and Kent Fitzgerald to reflect on how the stem cell field has progressed based on their experience working to attract top researchers to apply for our grants and watching our panel of outside reviewers select the top 20 to 30 percent of each set of applicants.

One of the biggest changes has been a move from animal stem cell models to work with human stem cells, and because of CIRM’s dedicated and sustained funding through the voter initiative Proposition 71, California scientists have led the way in this change. Kelly described examples of how mouse and human systems are different and having data on human cells has been critical to moving toward therapies.

Kelly and Kent address several technology trends. They note how quickly stem cell scientists have wrapped their arms around the new trendy gene editing technology CRISPR and discuss ways it is being used in the field. They also discuss the important role of our recently developed ability to perform single cell analysis and other technologies like using vessels called exosomes that carry some of the same factors as stem cells without having to go through all the issues around transplanting whole cells.

“We’re really looking to move things from discovery to the clinic. CIRM has laid the foundation by establishing a good understanding of mechanistic biology and how stem cells work and is now taking the knowledge and applying it for the benefit of patients,” Kent said toward the end of the interview.

jake and family

Jake Javier and his family

Jake’s story: one young man’s journey to and through a stem cell transplant; As a former TV writer and producer I tend to be quite critical about the way TV news typically covers medical stories. But a recent story on KTVU, the Fox News affiliate here in the San Francisco Bay Area, showed how these stories can be done in a way that balances hope, and accuracy.

Reporter Julie Haener followed the story of Jake Javier – we have blogged about Jake before – a young man who broke his spine and was then given a stem cell transplant as part of the Asterias Biotherapeutics clinical trial that CIRM is funding.

It’s a touching story that highlights the difficulty treating these injuries, but also the hope that stem cell therapies holds out for people like Jake, and of course for his family too.

If you want to see how a TV story can be done well, this is a great example.

Have Scientists Found a Stem Cell-lution to Thyroid Disorders?

The thyroid gland is located in the neck. (WebMD)

The thyroid gland is located in the neck. (WebMD)

Have you thanked your thyroid today? If not, you should because your thyroid is essential for many of life’s daily activities and processes that you probably take for granted.

You can thank your thyroid for things like regulating your body temperature and appetite, and keeping you energetic, slim, and focused. That’s because these small glands in your neck are hormone-producing factories, and thyroid secreted hormones (TSH) control the growth and development of our organs and tissues and regulate important processes like your metabolism.

When your thyroid doesn’t work…

People who have thyroid disorders suffer from a number of uncomfortable or even nasty symptoms. Those with overactive thyroid glands (hyperthyroidism) produce too much thyroid hormone and have an overactive metabolism, which causes symptoms such as excessive sweating, weight loss, heart problems, and sensitivity to heat. Those with underactive thyroids (hypothyroidism) don’t produce enough hormone and have an impaired metabolism, which causes symptoms of tiredness, reduced heart rate, hair loss, feeling cold, and weight gain.

There are other types of thyroid problems (cancer and inflammation to name a few), but the bottom line is that, if your thyroid isn’t functioning properly, your quality of life will be negatively affected.

A stem cell-lution to hypothyroidism

However, there maybe a new “stem cell-lution” therapy for some forms of thyroid dysfunction. Scientists from the Boston University School of Medicine and the Beth Israel Deaconess Medical Center reported in Cell Stem Cell on Thursday that they can generate functional thyroid tissue from stem cells derived from different mammalian models. This is a huge deal because previously, scientists were unable to manipulate pluripotent stem cells into mature thyroid cells that had the correct thyroid identity (meaning they turned on the correct combination of thyroid-specific genes). This previous inability has made it very difficult for scientists to model thyroid diseases in a dish.

In this study, the authors used two factors, BMP and FGF, to directly differentiate mouse pluripotent stem cells into thyroid progenitor cells. These progenitors could be coaxed further into mature and properly functioning thyroid organoids (3D thyroid-like structures) that secreted thyroid hormone both in a dish and when transplanted back into mice.

Scientists generated thyroid tissue from pluripotent stem cells of frogs, mice and humans. (Cell Stem Cell)

Scientists generated thyroid tissue from pluripotent stem cells of frogs, mice and humans. (Cell Stem Cell)

What was truly exciting about their discovery, was that the same two factors could make functional thyroid tissue from mouse, frog, and human pluripotent stem cells, showing that the role of BMP4 and FGF2 in thyroid development is conserved across multiple species.

With the bases loaded, the authors hit a grand slam by using BMP4 and FGF2 to generate thyroid progenitor cells from human embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) derived from the skin cells of both healthy individuals and patients with hypothyroidism.

Thyroid organoids generated from mouse embryonic stem cells. (Cell Stem Cell)

Thyroid organoids generated from mouse embryonic stem cells. (Cell Stem Cell)

Big Picture

This study not only offers a new understanding of the early stages of thyroid development, but provides a potential source of transplantable stem-cell derived thyroid progenitor cells for cell-based therapies that could treat some forms of hypothyroidism.

In a press release from the Beth Israel Deaconess Medical Center, co-senior author of the study Anthony Hollenberg explained the significance of their findings:

This research represents an important step toward the goal of being able to better treat thyroid diseases and being able to permanently rescue thyroid function through the transplantation of a patient’s own engineered pluripotent stem cells.

 

Co-senior author Darrell Kotton went further to describe the novelty of their discovery:

Until now, we haven’t fully understood the natural process that underlies early thyroid development. With this paper, we’ve identified the signaling pathways in thyroid cells that regulate their differentiation, the process by which unspecialized stem cells give rise to specialized cells during early fetal development.”

 

Remembering Anita Kurmann

Anita Kurmann

Anita Kurmann

While this discovery is a major step forward in the field of thyroid disease and regenerative medicine, the victory is bittersweet in light of the recent passing of the study’s first author, Anita Kurmann. Anita was a Swiss surgeon and a talented scientist who was tragically killed while riding her bike in Boston’s Back Bay on August 7th, 2015. She had just heard that her publication would be accepted to Cell Stem Cell days before the accident and was planning to start her own lab at the end of the year in Switzerland.

Her colleagues, friends, and the science world will miss her dearly. As a tribute to Anita, her co-authors dedicated the Cell Stem Cell publication to her memory.

We dedicate this work to the memory of our co-first author, Dr. Anita Kurmann, who died in a tragic bicycle accident when this manuscript was in the final stages of formatting. She was intelligent, well read, kind, humble, and tirelessly committed to her patients, her thyroid research, her family, and her colleagues, who miss her dearly.


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