Stanford Scientist Sergiu Pasca Receives Prestigious Vilcek Prize for Stem Cell Research on Neuropsychiatric Disorders

Sergiu Pasca, Stanford University

Last month, we blogged about Stanford neuroscientist Sergiu Pasca and his interesting research using stem cells to model the human brain in 3D. This month we bring you an exciting update about Dr. Pasca and his work.

On February 1st, Pasca was awarded one of the 2018 Vilcek Prizes for Creative Promise in Biomedical Science. The Vilcek Foundation is a non-profit organization dedicated to raising awareness of the important contributions made by immigrants to American arts and sciences.

Pasca was born in Romania and got his medical degree there before moving to the US to pursue research at Stanford University in 2009. He is now an assistant professor of psychiatry and behavioral sciences at Stanford and has dedicated his lab’s research to understanding human brain development and neuropsychiatric disorders using 3D brain organoid cultures derived from pluripotent stem cells.

The Vilcek Foundation produced a fascinating video (below) featuring Pasca’s life journey and his current CIRM-funded research on Timothy Syndrome – a rare form of autism. In the video, Pasca describes how his lab’s insights into this rare psychiatric disorder will hopefully shed light on other neurological diseases. He shares his hope that his research will yield something that translates to the clinic.

The Vilcek Prize for Creative Promise in Biomedical Science comes with a $50,000 cash award. Pasca along with the other prize winners will be honored at a gala event in New York City in April 2018.

You can read more about Pasca’s prize winning research on the Vilcek website and in past CIRM blogs below.


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Stem Cell Roundup: Rainbow Sherbet Fruit Fly Brains, a CRISPR/iPSC Mash-up and more

This week’s Round Up is all about the brain with some CRISPR and iPSCs sprinkled in:

Our Cool Stem Cell Image of the Week comes from Columbia University’s Zuckerman Institute:

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(Credit: Jon Enriquez/Mann Lab/Columbia’s Zuckerman Institute).

This rainbow sherbet-colored scientific art is a microscopy image of a fruit fly nervous system in which brain cells were randomly labeled with different colors. It was a figure in a Neuron study published this week showing how cells derived from the same stem cells can go down very different developmental paths but then later are “reunited” to carry out key functions, such as in this case, the nervous system control of leg movements.


A new therapeutic avenue for Parkinson’s diseaseBuck Institute

Many animal models of Parkinson’s disease are created by mutating specific genes to cause symptoms that mimic this incurable, neurodegenerative disorder. But, by far, most cases of Parkinson’s are idiopathic, a fancy term for spontaneous with no known genetic cause. So, researchers at the Buck Institute took another approach: they generated a mouse model of Parkinson’s disease using the pesticide, paraquat, exposure to which is known to increase the risk of the idiopathic form of Parkinson’s.

Their CIRM-funded study in Cell Reports showed that exposure to paraquat leads to cell senescence – in which cells shut down and stop dividing – particularly in astrocytes, brain cells that support the function of nerve cells. Ridding the mice of these astrocytes relieved some of the Parkinson’s like symptoms. What makes these results so intriguing is the team’s analysis of post-mortem brains from Parkinson’s patients also showed the hallmarks of increased senescence in astrocytes. Perhaps, therapeutic approaches that can remove senescent cells may yield novel Parkinson’s treatments.


Discovery may advance neural stem cell treatments for brain disordersSanford-Burnham Prebys Medical Discovery Institute (via Eureka Alert)

Another CIRM-funded study published this week in Nature Neuroscience may also help pave the way to new treatment strategies for neurologic disorders like Parkinson’s disease. A team at Sanford Burnham Prebys Medical Discovery Institute (SBP) discovered a novel gene regulation system that brain stem cells use to maintain their ability to self-renew.

The study centers around messenger RNA, a molecular courier that transcribes a gene’s DNA code and carries it off to be translated into a protein. The team found that the removal of a chemical tag on mRNA inside mouse brain stem cells caused them to lose their stem cell properties. Instead, too many cells specialized into mature brain cells leading to abnormal brain development in animal studies. Team lead Jing Crystal Zhao, explained how this finding is important for future therapeutic development:

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Crystal Zhao

“As NSCs are increasingly explored as a cell replacement therapy for neurological disorders, understanding the basic biology of NSCs–including how they self-renew–is essential to harnessing control of their in vivo functions in the brain.”


Researchers Create First Stem Cells Using CRISPR Genome ActivationThe Gladstone Institutes

Our regular readers are most likely familiar with both CRISPR gene editing and induced pluripotent stem cell (iPSC) technologies. But, in case you missed it late last week, a Cell Stem Cell study out of Sheng Ding’s lab at the Gladstone Institutes, for the first time, combined the two by using CRISPR to make iPSCs. The study got a lot of attention including a review by Paul Knoepfler in his blog The Niche. Check it out for more details!

 

Modeling the Human Brain in 3D

(Image from Pasca Lab, Stanford University)

Can you guess what the tiny white balls are in this photo? I’ll give you a hint, they represent the organ that you’re using right now to answer my question.

These are 3D brain organoids generated from human pluripotent stem cells growing in a culture dish. You can think of them as miniature models of the human brain, containing many of the brain’s various cell types, structures, and regions.

Scientists are using brain organoids to study the development of the human nervous system and also to model neurological diseases and psychiatric disorders. These structures allow scientists to dissect the inner workings of the brain – something they can’t do with living patients.

Brain-in-a-Dish

Dr. Sergiu Pasca is a professor at Stanford University who is using 3D cultures to understand human brain development. Pasca and his lab have previously published methods to make different types of brain organoids from induced pluripotent stem cells (iPSCs) that recapitulate human brain developmental events in a dish.

Sergiu Pasca, Stanford University (Image credit: Steve Fisch)

My colleague, Todd Dubnicoff, blogged about Pasca’s research last year:

“Using brain tissue grown from patient-derived iPSCs, Dr. Sergiu Pasca and his team recreated the types of nerve cell circuits that form during the late stages of pregnancy in the fetal cerebral cortex, the outer layer of the brain that is responsible for functions including memory, language and emotion. With this system, they observed irregularities in the assembly of brain circuitry that provide new insights into the cellular and molecular causes of neuropsychiatric disorders like autism.”

Pasca generated brain organoids from the iPSCs of patients with a genetic disease called Timothy Syndrome – a condition that causes heart problems and some symptoms of autism spectrum disorder in children. By comparing the nerve cell circuits in patient versus healthy brain organoids, he observed a disruption in the migration of nerve cells in the organoids derived from Timothy Syndrome iPSCs.

“We’ve never been able to recapitulate these human-brain developmental events in a dish before,” said Pasca in a press release, “the process happens in the second half of pregnancy, so viewing it live is challenging. Our method lets us see the entire movie, not just snapshots.”

The Rise of 3D Brain Cultures

Pasca’s lab is just one of many that are working with 3D brain culture technologies to study human development and disease. These technologies are rising in popularity amongst scientists because they make it possible to study human brain tissue in normal and abnormal conditions. Brain organoids have also appeared in the mainstream news as novel tools to study how epidemics like the Zika virus outbreak affect the developing fetal brain (more here and here).

While these advances are exciting and promising, the field is still in its early stages and the 3D organoid models are far from perfect at representing the complex biology of the human brain.

Pasca addresses the progress and the hurdles of 3D brain cultures in a review article titled “The rise of three-dimensional brain cultures” published this week in the journal Nature. The article, describes in detail how pluripotent stem cells can assemble into structures that represent different regions of the human brain allowing scientists to observe how cells interact within neural circuits and how these circuits are disrupted by disease.

The review goes on to compare different approaches for creating 3D brain cultures (see figure below) and their different applications. For instance, scientists are culturing organoids on microchips (brains-on-a-chip) to model the blood-brain barrier – the membrane structure that protects the brain from circulating pathogens in the blood but also makes drug delivery to brain very challenging. Brain organoids are also being used to screen for new drugs and to model complex diseases like Alzheimer’s.

Human pluripotent stem cells, adult stem cells or cancer cells  can be used to derive microfluidics-based organs-on-a-chip (top), undirected organoids (middle), and region-specific brain organoids or organ spheroids (bottom). These 3D cultures can be manipulated with CRISPR-Cas9 genome-editing technologies, transplanted into animals or used for drug screening. (Pasca, Nature)

Pasca ends the review by identifying the major hurdles facing 3D brain culture technologies. He argues that “3D cultures only approximate the appearance and architecture of neural tissue” and that the cells and structures within these organoids are not always predictable. These issues can be address over time by enforcing quality control in how these 3D cultures are made and by using new biomaterials that enable the expansion and maturation of these cultures.

Nonetheless, Pasca believes that 3D brain cultures combined with advancing technologies to study them have “the potential to give rise to novel features for studying human brain development and disease.”

He concludes the review with a cautiously optimistic outlook:

“This is an exciting new field and as with many technologies, it may follow a ‘hype’ cycle in which we overestimate its effects in the short run and underestimate its effects in the long run. A better understanding of the complexity of this platform, and bringing interdisciplinary approaches will accelerate our progress up a ‘slope of enlightenment’ and into the ‘plateau of productivity’.”

3D brain culture from the Pasca Lab, Stanford University


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Stem Cell RoundUp: CIRM Clinical Trial Updates & Mapping Human Brain

It was a very CIRMy news week on both the clinical trial and discovery research fronts. Here are some the highlights:

Stanford cancer-fighting spinout to Genentech: ‘Don’t eat me’San Francisco Business Times

Ron Leuty, of the San Francisco Business Times, reported this week on not one, but two news releases from CIRM grantee Forty Seven, Inc. The company, which originated from discoveries made in the Stanford University lab of Irv Weissman, partnered with Genentech and Merck KGaA to launch clinical trials testing their drug, Hu5F9-G4, in combination with cancer immunotherapies. The drug is a protein antibody that blocks a “don’t eat me” signal that cancer stem cells hijack into order to evade destruction by a cancer patient’s immune system.

Genentech will sponsor two clinical trials using its FDA-approved cancer drug, atezolizumab (TECENTRIQ®), in combination with Forty Seven, Inc’s product in patients with acute myeloid leukemia (AML) and bladder cancer. CIRM has invested $5 million in another Phase 1 trial testing Hu5F9-G4 in AML patients. Merck KGaA will test a combination treatment of its drug avelumab, or Bavencio, with Forty-Seven’s Hu5F9-G4 in ovarian cancer patients.

In total, CIRM has awarded Forty Seven $40.5 million in funding to support the development of their Hu5F9-G4 therapy product.


Novel regenerative drug for osteoarthritis entering clinical trialsThe Scripps Research Institute

The California Institute for Biomedical Research (Calibr), a nonprofit affiliate of The Scripps Research Institute, announced on Tuesday that its CIRM-funded trial for the treatment of osteoarthritis will start treating patients in March. The trial is testing a drug called KA34 which prompts adult stem cells in joints to specialize into cartilage-producing cells. It’s hoped that therapy will regenerate the cartilage that’s lost in OA, a degenerative joint disease that causes the cartilage that cushions joints to break down, leading to debilitating pain, stiffness and swelling. This news is particularly gratifying for CIRM because we helped fund the early, preclinical stage research that led to the US Food and Drug Administration’s go-ahead for this current trial which is supported by a $8.4 million investment from CIRM.


And finally, for our Cool Stem Cell Image of the Week….

Genetic ‘switches’ behind human brain evolutionScience Daily

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This artsy scientific imagery was produced by UCLA researcher Luis del la Torre-Ubieta, the first author of a CIRM-funded studied published this week in the journal, Cell. The image shows slices of the mouse (bottom middle), macaque monkey (center middle), and human (top middle) brain to scale.

The dramatic differences in brain size highlights what sets us humans apart from those animals: our very large cerebral cortex, a region of the brain responsible for thinking and complex communication. Torre-Ubieta and colleagues in Dr. Daniel Geschwind’s laboratory for the first time mapped out the genetic on/off switches that regulate the growth of our brains. Their results reveal, among other things, that psychiatric disorders like schizophrenia, depression and Attention-Deficit/Hyperactivity Disorder (ADHD) have their origins in gene activity occurring in the very earliest stages of brain development in the fetus. The swirling strings running diagonally across the brain slices in the image depict DNA structures, called chromatin, that play a direct role in the genetic on/off switches.

CIRM interviews Lorenz Studer: 2017 recipient of the Ogawa-Yamanaka Stem Cell Prize [Video]

For eight long years, researchers who were trying to develop a stem cell-based therapy for Parkinson’s disease – an incurable movement disorder marked by uncontrollable shaking, body stiffness and difficulty walking – found themselves lost in the proverbial wilderness. In initial studies, rodent stem cells were successfully coaxed to specialize into dopamine-producing nerve cells, the type that are lost in Parkinson’s disease. And further animal studies showed these cells could treat Parkinson’s like symptoms when transplanted into the brain.

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Lorenz Studer, MD
Photo Credit: Sloan Kettering

But when identical recipes were used to make human stem cell-derived dopamine nerve cells the same animal experiments didn’t work. By examining the normal developmental biology of dopamine neurons much more closely, Lorenz Studer cracked the case in 2011. Now seven years later, Dr. Studer, director of the Center for Stem Cell Biology at the Memorial-Sloan Kettering Cancer Center, and his team are on the verge of beginning clinical trials to test their Parkinson’s cell therapy in patients

It’s for these bottleneck-busting contributions to the stem cell field that Dr. Studer was awarded the Gladstone Institutes’ 2017 Ogawa-Yamanaka Stem Cell Prize. Now in its third year, the prize was founded by philanthropists Hiro and Betty Ogawa along with  Shinya Yamanaka, Gladstone researcher and director of the Center for iPS Cell Research and Application at Kyoto University, and is meant to inspire and celebrate discoveries that build upon Yamanaka’s Nobel prize winning discovery of induced pluripotent stem cells (iPSCs).

LorenzStuder_OgawaAward2017-12

(L to R) Shinya Yamanaka, Andrew Ogawa, Deepak Srivastava present Lorenz Studer the 2017 Ogawa-Yamanaka Stem Cell Prize at Gladstone Institutes. Photo Credit: Todd Dubnicoff/CIRM

Studer was honored at the Gladstone in November and presented the Ogawa-Yamanka Stem Cell Prize Lecture. He was kind enough to sit down with me for a brief video interview (watch it below) a few minutes before he took the stage. He touched upon his Parkinson’s disease research as well as newer work related to hirschsprung disease, a dangerous intestinal disorder often diagnosed at birth that is caused by the loss of nerve cells in the gut. Using human embryonic stem cells and iPSCs derived from hirschsprung patients, Studer’s team has worked out the methods for making the gut nerve cells that are lost in the disease. This accomplishment has allowed his lab to better understand the disease and to make solid progress toward a stem cell-based therapy.

His groundbreaking work has also opened up the gates for other Parkinson’s researchers to make important insights in the field. In fact, CIRM is funding several interesting early stage projects aimed at moving therapy development forward:

We posted the 8-minute video with Dr. Studer today on our official YouTube channel, CIRM TV. You can watch the video here:

And for a more detailed description of Studer’s research, watch Gladstone’s webcast recording of his entire lecture:

Hey, what’s the big idea? CIRM Board is putting up more than $16.4 million to find out

Higgins

David Higgins, CIRM Board member and Patient Advocate for Parkinson’s disease; Photo courtesy San Diego Union Tribune

When you have a life-changing, life-threatening disease, medical research never moves as quickly as you want to find a new treatment. Sometimes, as in the case of Parkinson’s disease, it doesn’t seem to move at all.

At our Board meeting last week David Higgins, our Board member and Patient Advocate for Parkinson’s disease, made that point as he championed one project that is taking a new approach to finding treatments for the condition. As he said in a news release:

“I’m a fourth generation Parkinson’s patient and I’m taking the same medicines that my grandmother took. They work but not for everyone and not for long. People with Parkinson’s need new treatment options and we need them now. That’s why this project is worth supporting. It has the potential to identify some promising candidates that might one day lead to new treatments.”

The project is from Zenobia Therapeutics. They were awarded $150,000 as part of our Discovery Inception program, which targets great new ideas that could have a big impact on the field of stem cell research but need some funding to help test those ideas and see if they work.

Zenobia’s idea is to generate induced pluripotent stem cells (iPSCs) that have been turned into dopaminergic neurons – the kind of brain cell that is dysfunctional in Parkinson’s disease. These iPSCs will then be used to screen hundreds of different compounds to see if any hold potential as a therapy for Parkinson’s disease. Being able to test compounds against real human brain cells, as opposed to animal models, could increase the odds of finding something effective.

Discovering a new way

The Zenobia project was one of 14 programs approved for the Discovery Inception award. You can see the others on our news release. They cover a broad array of ideas targeting a wide range of diseases from generating human airway stem cells for new approaches to respiratory disease treatments, to developing a novel drug that targets cancer stem cells.

Dr. Maria Millan, CIRM’s President and CEO, said the Stem Cell Agency supports this kind of work because we never know where the next great idea is going to come from:

“This research is critically important in advancing our knowledge of stem cells and are the foundation for future therapeutic candidates and treatments. Exploring and testing new ideas increases the chances of finding treatments for patients with unmet medical needs. Without CIRM’s support many of these projects might never get off the ground. That’s why our ability to fund research, particularly at the earliest stage, is so important to the field as a whole.”

The CIRM Board also agreed to invest $13.4 million in three projects at the Translation stage. These are programs that have shown promise in early stage research and need funding to do the work to advance to the next level of development.

  • $5.56 million to Anthony Oro at Stanford to test a stem cell therapy to help people with a form of Epidermolysis bullosa, a painful, blistering skin disease that leaves patients with wounds that won’t heal.
  • $5.15 million to Dan Kaufman at UC San Diego to produce natural killer (NK) cells from embryonic stem cells and see if they can help people with acute myelogenous leukemia (AML) who are not responding to treatment.
  • $2.7 million to Catriona Jamieson at UC San Diego to test a novel therapeutic approach targeting cancer stem cells in AML. These cells are believed to be the cause of the high relapse rate in AML and other cancers.

At CIRM we are trying to create a pipeline of projects, ones that hold out the promise of one day being able to help patients in need. That’s why we fund research from the earliest Discovery level, through Translation and ultimately, we hope into clinical trials.

The writer Victor Hugo once said:

“There is one thing stronger than all the armies in the world, and that is an idea whose time has come.”

We are in the business of finding those ideas whose time has come, and then doing all we can to help them get there.

 

 

 

Stem cell stories that caught our eye: the tale of a tail that grows back and Zika’s devious Trojan Horse

The tale of a tail that grows back (Kevin McCormack)

Ask people what they know about geckos and the odds are they’ll tell you geckos have English accents and sell car insurance. Which tells you a lot more about the power of advertising than it does about the level of knowledge about lizards. Which is a shame, because the gecko has some amazing qualities, not the least of which is its ability to re-grow its tail. Now some researchers have discovered how it regenerates its tail, and what they’ve learned could one day help people with spinal cord injuries.

Geckos often detach a bit of their tail when being pursued by a predator, then grow a new one over the course of 30 days. Researchers at the University of Guelph in Canada found that the lizards use a combination of stem cells and proteins to do that.

They found that geckos have stem cells in their tail called radial glias. Normally these cells are dormant but that changes when the lizard loses its tail. As Matthew Vickaryous, lead author of the study, said in a news release:

“But when the tail comes off everything temporarily changes. The cells make different proteins and begin proliferating more in response to the injury. Ultimately, they make a brand new spinal cord. Once the injury is healed and the spinal cord is restored, the cells return to a resting state.”

Vickaryous hopes that understanding how the gecko can repair what is essentially an injury to its spinal cord, we’ll be better able to develop ways to help people with the same kind of injury.

The study is published in the Journal of Comparative Neurology.

Zika virus uses Trojan Horse strategy to infect developing brain
In April 2015, the World Health Organization declared that infection by Zika virus and its connection to severe birth defects was an international public health emergency. The main concern has been the virus’ link to microcephaly, a condition in which abnormal brain development causes a smaller than normal head size at birth. Microcephaly leads to number of problems in these infants including developmental delays, seizures, hearing loss and difficulty swallowing.

A false color micrograph shows microglia cells (green) infected by the Zika virus (blue). Image Muotri lab/UCSD

Since that time, researchers have been racing to better understand how Zika infection affects brain development with the hope of finding treatment strategies. Now, a CIRM-funded study in Human Molecular Genetics reports important new insights about how Zika virus may be transmitted from infected pregnant women to their unborn babies.

The UCSD researchers behind the study chose to focus on microglia cells. In a press release, team leader Alysson Muotri explained their rationale for targeting these cells:

“During embryogenesis — the early stages of prenatal development — cells called microglia form in the yolk sac and then disperse throughout the central nervous system (CNS) of the developing child. Considering the timing of [Zika] transmission, we hypothesized that microglia might be serving as a Trojan horse to transport the virus during invasion of the CNS.”

In the developing brain, microglia continually travel throughout the brain and clear away dead or infected cells. Smuggling itself aboard microglia would give Zika a devious way to slip through the body’s defenses and infect other brain cells. And that’s exactly what Dr. Muotri’s team found.

Using human induced pluripotent stem cells (iPSCs), they generated brain stem cells – the kind found in the developing brain – and in lab dish infected them with Zika virus. When iPSC-derived microglia were added to the infected neural stem cells, the microglia gobbled them up and destroyed them, just as they would do in the brain. But when those microglia were placed next to uninfected brain stem cells, the Zika virus was easily transmitted to those cells. Muotri summed up the results this way:

“Our findings show that the Zika virus can infect these early microglia, sneaking into the brain where they transmit the virus to other brain cells, resulting in the devastating neurological damage we see in some newborns.”

The team went on to show that an FDA-approved drug to treat hepatitis – a liver disease often caused by viral infection – was effective at decreasing the infection of brain stem cells by Zika-carrying microglia. Since these studies were done in petri dishes, more research will be required to confirm that the microglia are a true drug target for stopping the devastating impact of Zika on newborns.

Stanford scientists are growing brain stem cells in bulk using 3D hydrogels

This blog is the final installment in our #MonthofCIRM series. Be sure to check out our other blogs highlighting important advances in CIRM-funded research and initiatives.

Neural stem cells from the brain have promising potential as cell-based therapies for treating neurological disorders such as Alzheimer’s disease, Parkinson’s, and spinal cord injury. A limiting factor preventing these brain stem cells from reaching the clinic is quantity. Scientists have a difficult time growing large populations of brain stem cells in an efficient, cost-effective manner while also maintaining the cells in a stem cell state (a condition referred to as “stemness”).

CIRM-funded scientists from Stanford University are working on a solution to this problem. Dr. Sarah Heilshorn, an associate professor of Materials Science and Engineering at Stanford, and her team are engineering 3D hydrogel technologies to make it easier and cheaper to expand high-quality neural stem cells (NSCs) for clinical applications. Their research was published yesterday in the journal Nature Materials.

Stem Cells in 3D

Similar to how moviegoers prefer to watch the latest Star Wars installment in 3D, compared to the regular screen, scientists are turning to 3D materials called hydrogels to grow large numbers of stem cells. Such an environment offers more space for the stem cells to proliferate and expand their numbers while keeping them happy in their stem cell state.

To find the ideal conditions to grow NSCs in 3D, Heilshorn’s team tested two important properties of hydrogels: stiffness and degradability (or how easy it is to remodel the structure of the hydrogel material). They designed a range of hydrogels, made from proteins with elastic qualities, that varied in these two properties. Interestingly, they found that the stiffness of the material did not have a profound effect on the “stemness” of NSCs. This result contrasts with other types of adult stem cells like muscle stem cells, which quickly differentiate into mature muscle cells when exposed to stiffer materials.

On the other hand, the researchers found that it was crucial for the NSCs to be able to remodel their 3D environment. NSCs maintained their stemness by secreting enzymes that broke down and rearranged the molecules in the hydrogels. If this enzymatic activity was blocked, or if the cells were grown in hydrogels that couldn’t be remodeled easily, NSCs lost their stemness and stopped proliferating. The team tested two other hydrogel materials and found the same results. As long as the NSCs were in a 3D environment they could remodel, they were able to maintain their stemness.

NSCs maintain their stemness in hydrogels that can be remodeled easily. Nestin (green) and Sox2 (red) are markers that indicate “high-quality” NSCs. (Image courtesy of Chris Madl, Stanford)

Caption: NSCs maintain their stemness in hydrogels that can be remodeled easily. Nestin (green) and Sox2 (red) are markers that indicate “high-quality” NSCs. (Images courtesy of Chris Madl)

Christopher Madl, a PhD student in the Heilshorn lab and the first author on the study, explained how remodeling their 3D environment allows NSCs to grow robustly in an interview with the Stem Cellar:

Chris Madl

“In this study, we identified that the ability of the neural stem cells to dynamically remodel the material was critical to maintaining the correct stem cell state. Being able to remodel (or rearrange) the material permitted the cells to contact each other.  This cell-cell contact is responsible for maintaining signals that allow the stem cells to stay in a stem-like state. Our findings allow expansion of neural stem cells from relatively low-density cultures (aiding scale-up) without the use of expensive chemicals that would otherwise be required to maintain the correct stem cell behavior (potentially decreasing cost).”

To 3D and Beyond

When asked what’s next on the research horizon, Heilshorn said two things:

Sarah Heilshorn

“First, we want to see if other stem cell types – for example, pluripotent stem cells – are also sensitive to the “remodel-ability” of materials. Second, we plan to use our discovery to create a low-cost, reproducible material for efficient expansion of stem cells for clinical applications. In particular, we’d like to explore the use of a single material platform that is injectable, so that the same material could be used to expand the stem cells and then transplant them.”

Heilshorn is planning to apply the latter idea to advance another study that her team is currently working on. The research, which is funded by a CIRM Tools and Technologies grant, aims to develop injectable hydrogels containing NSCs derived from human induced pluripotent stem cells to treat mice, and hopefully one day humans, with spinal cord injury. Heilshorn explained,

“In our CIRM-funded studies, we learned a lot about how neural stem cells interact with materials. This lead us to realize that there’s another critical bottleneck that occurs even before the stage of transplantation: being able to generate a large enough number of high-quality stem cells for transplantation. We are developing materials to improve the transplantation of stem cell-derived therapies to patients with spinal cord injuries. Unfortunately, during the transplantation process, a lot of cells can get damaged. We are now creating injectable materials that prevent this cell damage during transplantation and improve the survival and engraftment of NSCs.”

An injectable material that promotes the expansion of large populations of clinical grade stem cells that can also differentiate into mature cells is highly desired by scientists pursuing the development of cell replacement therapies. Heilshorn and her team at Stanford have made significant progress on this front and are hoping that in time, this technology will prove effective enough to reach the clinic.

CIRM stories that caught our eye: UCSD team stops neuromuscular disease in mice, ALS trial enrolls 1st patients and Q&A with CIRM Prez

Ordinarily, we end each week at the Stem Cellar with a few stem cell stories that caught our eye. But, for the past couple of weeks we’ve been busy churning out stories related to our Month of CIRM blog series, which we hope you’ve found enlightening. To round out the series, we present this “caught our eye” blog of CIRM-specific stories from the last half of October.

Stopping neurodegenerative disorder with blood stem cells. (Karen Ring)

CIRM-funded scientists at the UC San Diego School of Medicine may have found a way to treat a progressive neuromuscular disorder called Fredreich’s ataxia (FA). Their research was published last week in the journal Science Translational Medicine.

FA is a genetic disease that attacks the nervous tissue in the spinal cord leading to the loss of sensory nerve cells that control muscle movement. Early on, patients with FA experience muscle weakness and loss of coordination. As the disease progresses, FA can cause scoliosis (curved spine), heart disease and diabetes. 1 in 50,000 Americans are afflicted with FA, and there is currently no effective treatment or cure for this disease.

cherqui

In this reconstituted schematic, blood stem cells transplanted in a mouse model of Friedreich’s ataxia differentiate into microglial cells (red) and transfer mitochondrial protein (green) to neurons (blue), preventing neurodegeneration. Image courtesy of Stephanie Cherqui, UC San Diego School of Medicine.

UCSD scientists, led by CIRM grantee Dr. Stephanie Cherqui, found in a previous study that transplanting blood stem and progenitor cells was an effective treatment for preventing another genetic disease called cystinosis in mice. Cherqui’s cystinosis research is currently being funded by a CIRM late stage preclinical grant.

In this new study, the UCSD team was curious to find out whether a similar stem cell approach could also be an effective treatment for FA. The researchers used an FA transgenic mouse model that was engineered to harbor two different human mutations in a gene called FXN, which produces a mitochondrial protein called frataxin. Mutations in FXN result in reduced expression of frataxin, which eventually leads to the symptoms experienced by FA patients.

When they transplanted healthy blood stem and progenitor cells (HSPCs) from normal mice into FA mice, the cells developed into immune cells called microglia and macrophages. They found the microglia in the brain and spinal cord and the macrophages in the spinal cord, heart and muscle tissue of FA mice that received the transplant. These normal immune cells produced healthy frataxin protein, which was transferred to disease-affected nerve and muscle cells in FA mice.

Cherqui explained their study’s findings in a UC San Diego Health news release:

“Transplantation of wildtype mouse HSPCs essentially rescued FA-impacted cells. Frataxin expression was restored. Mitochondrial function in the brains of the transgenic mice normalized, as did in the heart. There was also decreased skeletal muscle atrophy.”

In the news release, Cherqui’s team acknowledged that the FA mouse model they used does not perfectly mimic disease progression in humans. In future studies, the team will test their method on other mouse models of FA to ultimately determine whether blood stem cell transplants will be an effective treatment option for FA patients.

Brainstorm’s CIRM funded clinical trial for ALS enrolls its first patients
“We have been conducting ALS clinical trials for more than two decades at California Pacific Medical Center (CPMC) and this is, by far, the most exciting trial in which we have been involved to date.”

Those encouraging words were spoken by Dr. Robert Miller, director of CPMC’s Forbes Norris ALS Research Center in an October 16th news release posted by Brainstorm Cell Therapeutics. The company announced in the release that they had enrolled the first patients in their CIRM-funded, stem cell-based clinical trial for the treatment of amyotrophic lateral sclerosis (ALS).

BrainStorm

Also known as Lou Gehrig’s disease, ALS is a cruel, devastating disease that gradually destroys motor neurons, the cells in the brain or spinal cord that instruct muscles to move. People with the disease lose the ability to move their muscles and, over time, the muscles atrophy leading to paralysis. Most people with ALS die within 3 to 5 years from the onset of symptoms and there is no effective therapy for the disease.

Brainstorm’s therapy product, called NurOwn®, is made from mesenchymal stem cells that are taken from the patient’s own bone marrow. These stem cells are then modified to boost their production and release of factors, which are known to help support and protect the motor neurons destroyed by the disease. Because the cells are derived directly from the patient, no immunosuppressive drugs are necessary, which avoids potentially dangerous side effects. The trial aims to enroll 200 patients and is a follow up of a very promising phase 2 trial. CIRM’s $16 million grant to the Israeli company which also has headquarters in the United States will support clinical studies at multiple centers in California. And Abla Creasey, CIRM’s Senior Director of Strategic Infrastructure points out in the press release, the Agency support of this trial goes beyond this single grant:

“Brainstorm will conduct this trial at multiple sites in California, including our Alpha Clinics Network and will also manufacture its product in California using CIRM-funded infrastructure.”

An initial analysis of the effectiveness of NurOwn® in this phase 3 trial is expected in 2019.

CIRM President Maria Millan reflects on her career, CIRM’s successes and the outlook for stem cell biology 

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Maria T. Millan, M.D., CIRM President and CEO

RegMedNet a networking website that provides content related to the regenerative medicine community, published an interview this morning with Maria Millan, M.D., CIRM’s new President and CEO. The interview covers the impressive accomplishments that Dr. Millan had achieved before coming to CIRM, with details that even some of us CIRM team members may not have been aware of. In addition to describing her pre-CIRM career, Dr. Millan also describes the Agency’s successes during her term as Vice President of CIRM’s Therapeutics group and she gives her take on future of Agency and the stem cell biology field in general over the next five years and beyond. File this article under “must read”.

CIRM-Funded Clinical Trials Targeting Brain and Eye Disorders

This blog is part of our Month of CIRM series, which features our Agency’s progress towards achieving our mission to accelerate stem cell treatments to patients with unmet medical needs.

 This week, we’re highlighting CIRM-funded clinical trials to address the growing interest in our rapidly expanding clinical portfolio. Our Agency has funded a total of 40 trials since its inception. 23 of these trials were funded after the launch of our Strategic Plan in 2016, bringing us close to the half way point of our goal to fund 50 new clinical trials by 2020.

Today we are featuring CIRM-funded trials in our neurological and eye disorders portfolio.  CIRM has funded a total of nine trials targeting these disease areas, and seven of these trials are currently active. Check out the infographic below for a list of our currently active trials.

For more details about all CIRM-funded clinical trials, visit our clinical trials page and read our clinical trials brochure which provides brief overviews of each trial.