Author: Todd Dubnicoff

Deep dive into muscle repair yields new strategies to combat Duchenne muscular dystrophy

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Researchers at the Sanford Burnham Prebys Medical Discovery Institute (SBP) reported new findings this week that may lead to novel therapeutic strategies for people suffering from Duchenne muscular dystrophy (DMD). DMD, a muscle-wasting disease that affects 1 in 7250 males aged 5 to 24 years in the United States, is caused by a genetic mutation leading to the lack of a protein called dystrophin. Without dystrophin, muscle cells become fragile and are easily damaged. Instead of self-repair, the muscles are replaced by scar tissue, a process called fibrosis that leads to muscle degeneration and wasting.

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Dystrophin, a protein that maintains the structural integrity of muscle fibers, is missing in people with DMD. Image credit: Khan Academy

Boys with DMD first show signs of muscle weakness between ages 3-5 and often stop walking by the time they’re teenagers. Eventually the muscles critical for breathing and heart function stop working. Average life expectancy is 26 and there is no cure.

The SBP scientists are aiming to treat DMD by boosting muscle repair in affected individuals. But to do that, they sought to better understand how muscle regeneration works in the first place. In the current study, they focused their efforts on so-called fibro/adipogenic precursor (FAP) cells which, in response to acute injury, appear to play a role in stimulating muscle stem cells to divide and replace damaged muscle in healthy individuals. But FAPs are also implicated in the muscle wasting and scarring that’s seen in DMD.

By examining the gene activity of single FAP cells from mouse models of acute injury and DMD, the researchers identified a sub-population of FAP cells (sub-FAPs). Further study of these sub-FAPs showed that during early stages of muscle regeneration, these cells promote muscle stem cell activation but then at later stages, sub-FAPs – identified by a cell surface protein called Vcam1 – stimulate fibrosis. It turns out that during healthy acute muscle injury, the sub-FAPs with cell-surface Vcam1 protein are readily eaten up and removed by immune cells thereby avoiding muscle fibrosis. But in the DMD mouse model, removal of these sub-FAPs is impaired and instead collagen deposits and muscle fibrosis occur which are hallmarks of the progressive degeneration seen in DMD.

Barbora Malecova, Ph.D., a first author of the study, explained the implications of these results in a press release:

“This study elucidates the cellular and molecular pathogenesis of muscular dystrophy. These results indicate that removing or modulating the activity of Vcam1-positive sub-FAPs, which promote fibrosis, could be an effective treatment for DMD.”

The lab, led by Pier Lorenzo Puri, M.D., next will explore the possibility of finding drugs that target the Vcam1 sub-FAPs which in turn could help prevent fibrosis in DMD.

The study, funded in part by CIRM, appears in Nature Communications. CIRM is also funding a Phase 2 clinical trial testing a stem cell-based therapy that aims to improve the life-threatening heart muscle degeneration that occurs in DMD patients.

Join us tomorrow at noon for “Ask the Stem Cell Team about Sickle Cell Disease”, a FaceBook Live Event

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As an early kick off to National Sickle Cell Awareness Month – which falls in September every year – CIRM is hosting a “Ask the Stem Cell Team” FaceBook Live event tomorrow, August 28th, from noon to 1pm (PDT).

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The live broadcast will feature two scientists and a patient advocate who are working hard to bring an end to sickle cell disease, a devastating, inherited blood disorder that largely targets the African-American community and to a lesser degree the Hispanic community.

You can join us by logging onto Facebook and going to this broadcast link: https://bit.ly/2o4aCAd

Also, make sure to “like” our FaceBook page before the event to receive a notification when we’ve gone live for this and future events. If you miss tomorrow’s broadcast, not to worry. We’ll be posting it on our Facebook video page, our website, and YouTube channel shortly afterwards.

We want to answer your most pressing questions, so please email them directly to us beforehand at info@cirm.ca.gov.

For a sneak preview here’s a short video featuring our patient advocate speaker, Adrienne Shapiro. And see below for more details about Ms. Shapiro and our two other guests.

Adrienne Shapiro [Video: Todd Dubnicoff/CIRM]

  • Dr. Donald B. KohnUCLA MIMG BSCRC Faculty 180118

    Donald Kohn, MD

    Don Kohn, M.D. is a professor in the departments of Pediatrics and Microbiology, Immunology and Molecular Genetics in UCLA’s Broad Stem Cell Research Center. Dr. Kohn has a CIRM Clinical Stage Research grant in support of his team’s Phase 1 clinical trial which is genetically modifying a patient’s own blood stem cells to produce a correct version of hemoglobin, the protein that is mutated in these patients, which causes abnormal sickle-like shaped red blood cells. These misshapen cells lead to dangerous blood clots, debilitating pain and even death. The genetically modified stem cells will be given back to the patient to create a new sickle cell-free blood supply.

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    Mark Walters, MD

    Mark Walters, M.D., is a pediatric hematologist/oncologist and is director of the Blood & Marrow Transplantation Program at UCSF Benioff Children’s Hospital Oakland. Dr. Walters has a CIRM-funded Therapeutic Translation Research grant which aims to improve Sickle Cell Disease (SCD) therapy by preparing for a clinical trial that might cure SCD after giving back sickle gene-corrected blood stem cells – using cutting-edge CRISPR gene editing technology – to a person with SCD. If successful, this would be a universal life-saving and cost-saving therapy.

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    Adrienne Shapiro

    Adrienne Shapiro is a patient advocate for SCD and the co-founder of the Axis Advocacy SCD patient education and support website. Shapiro is the fourth generation of mothers in her family to have children born with sickle cell disease.  She is vocal stem cell activist, speaking to various groups about the importance of CIRM’s investments in both early stage research and clinical trials. In January, she was awarded a Stem Cell and Regenerative Medicine Action Award at the 2018 World Stem Cell Summit.

Stem cell stories that caught our eye: CIRM-funded scientist wins prestigious prize and a tooth trifecta

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CIRM-grantee wins prestigious research award

Do we know how to pick ‘em or what? For a number of years now we have been funding the work of Stanford’s Dr. Marius Wernig, who is doing groundbreaking work in helping advance stem cell research. Just how groundbreaking was emphasized this week when he was named as the winner of the 2018 Ogawa-Yamanaka Stem Cell Prize.

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Marius Wernig, MD, PhD. [Photo: Stanford University]

The prestigious award, from San Francisco’s Gladstone Institutes, honors Wernig for his innovative work in developing a faster, more direct method of turning ordinary cells into, for example, brain cells, and for his work advancing the development of disease models for diseases of the brain and skin disorders.

Dr. Deepak Srivastava, the President of Gladstone, announced the award in a news release:

“Dr. Wernig is a leader in his field with extraordinary accomplishments in stem cell reprogramming. His team was the first to develop neuronal cells reprogrammed directly from skin cells. He is now investigating therapeutic gene targeting and cell transplantation–based strategies for diseases with mutations in a single gene.”

Wernig was understandably delighted at the news:

“It is a great honor to receive this esteemed prize. My lab’s goal is to discover novel biology using reprogrammed cells that aids in the development of effective treatments.”

Wernig will be presented with the award, and a check for $150,000, at a ceremony on Oct. 15 at the Gladstone Institutes in San Francisco.

A stem cell trifecta for teeth research

It was a tooth trifecta among stem cell scientists this week. At Tufts University School of Medicine, researchers made an important advance in the development of bioengineered teeth. The current standard for tooth replacement is a dental implant. This screw-shaped device acts as an artificial tooth root that’s inserted into the jawbone. Implants have been used for 30 years and though successful they can lead to implant failure since they lack many of the properties of natural teeth. By implanting postnatal dental cells along with a gel material into mice, the team demonstrated, in a Journal of Dental Research report, the development of natural tooth buds. As explained in Dentistry Today, these teeth “include features resembling natural tooth buds such as the dental epithelial stem cell niche, enamel knot signaling centers, transient amplifying cells, and mineralized dental tissue formation.”

Another challenge with the development of a bioengineered tooth replacement is reestablishing nerve connections within the tooth, which plays a critical role in its function and protection but doesn’t occur spontaneously after an injury. A research team across the “Pond” at the French National Institute of Health and Medical Research, showed that bone marrow-derived mesenchymal stem cells in the presence of a nerve fiber can help the nerve cells make connections with bioengineered teeth. The study was also published in the Journal of Dental Research.

And finally, a research report about stem cells and the dreaded root canal. When the living soft tissue, or dental pulp, of a tooth becomes infected, the primary course of action is the removal of that tissue via a root canal. The big downside to this procedure is that it leaves the patient with a dead tooth which can be susceptible to future infections. To combat this side effect, researchers at the New Jersey Institute of Technology report the development of a potential remedy: a gel containing a fragment of a protein that stimulates the growth of new blood vessels as well as a fragment of a protein that spurs dental stem cells to divide and grow. Though this technology is still at an early stage, it promises to help keep teeth alive and healthy after root canal. The study was presented this week at the National Meeting of the American Chemical Society.

Here’s an animated video that helps explain the research:

Stem cell summer: high school students document internships via social media, Part 3

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Today we share our third and final pair of social media awards from CIRM’s 2018 SPARK (Summer Program to Accelerate Regenerative medicine Knowledge) program, a 6-12 week summer internship program that provides hands-on stem cell research training to high school students throughout California.

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CIRM SPARK 2018 Best Instagram Post winner by Caltech SPARK intern Anthony Tan

As part of their curriculum, the students were asked to write a blog and to post Instagram photos (follow #cirmsparklab) to document their internship experiences. Several CIRM team members selected their favorite entries and presented awards to the winning interns at the SPARK Student Conference earlier this month at UC Davis.

The two winners featured today are Caltech SPARK student, Anthony Tan – a senior at John A. Rowland High School – one of the Instagram Award winners (see his Instagram post above) and UCSF SPARK student Gennifer Hom – a senior at Ruth Asawa School of the Arts – one of the Blog Award winners. Read her blog below. (To learn about the other 2018 social media winners, see our previous blog posts here and here.)

Best Blog Award:
My SPARK 2018 summer stem cell research internship experience
By Gennifer Hom

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Gennifer Hom

When I was seven, I remember looking up at the stars, I stared hard at the moon through my car window, thinking that it only revolves around me as it followed me home. I later learned in class that we rotate around the sun, as gravity holds the spinning planets in place, simultaneously, the moon revolves around the earth. Out of nowhere, I abruptly felt an actual light bulb switched on above my head once I learned how day and night came. Overcome with curiosity,“ Where did the Big Bang take place? When will my Big Bang happen?”

My interest dissipated as I entered into my high school career. I was struck with incoherence, an inconsistency to my thoughts, as I leaned my shoulder against the wall—for I had already decided to let my fatigue to take over. I felt lacking, unconfident in my abilities even to solve a simple balance chemical equation in chemistry class. Science was not my forte. I could never see myself working in a lab setting.

Still, a spark within me still held onto that childhood curiosity of mine. I remember sitting on the bus on my way to school reading about stem cells, which were fascinating to me. We can use these little cells for so many scientific research.

My Big Bang unfolded when I was accepted into the UCSF SEP internship program. I
studied the human-specific population of cortical neural stem cells and evaluated the signaling mechanisms that govern the formation of their identity. Through my performance, I am also contributing to this phenomenal study, helping my community by potentially providing information to help cure mental illnesses. At times, the results of our data did not come out as we wanted it to be. The staining went wrong, and the images were lacking. I would have to repeat the experiment or troubleshoot on the spot continually. However, it’s all a learning process. Even if I do get beautiful image stainings, I still need to repeat the experiments to confirm my results.

Learning was not the only side that is needed under this program. CIRM encouraged us to share our internship experiences on social media. I posted once a week on my studies, what I’ve learned, and how I could teach my viewers about this new research I am performing. I remember in one of the first few meetings we had, where we had to share our research with our peers, “ I can actually understand your studies,” a friend of mine claimed.

I felt powerful, in a sense, that I was able to communicate my knowledge to others to help them understand and teach my study. When I talk to my family and friends about my summer, I feel confident in my ability to comprehend these complex ideas. I could see myself researching, engineering, and fighting for a solution. I want to find the best form of gene therapy, and map each neuron of the brain. Through this two month program, science has become a new passion for me, a cornerstone of my new academic pursuits. It strengthened my theoretical knowledge and gave me an experience where I witnessed the real world laboratory setting. Not only did I learn the fundamental techniques of immunohistochemistry and microscopy, but I was able to receive encouraging advice from the scientists in the Kriegsteins lab and especially my mentor, Madeline Andrews. The experience in a lab comforted me by the idea of the never-ending changes that lured me to a world of thought and endless potential.

Stem cell stories that caught our eye: 3 blind mice no more and a tale of two tails

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Stem cell image of the week: The demise of Three Blind Mice nursery rhyme (Todd Dubnicoff)
Our stem cell image of the week may mark the beginning of the end of the Three Blind Mice nursery rhyme and, more importantly, usher in a new treatment strategy for people suffering from vision loss. That’s because researchers from Icahn School of Medicine at Mount Sinai, New York report in Nature the ability to reprogram support cells in the eyes of blind mice to become photoreceptors, the light-sensing cells that enable sight. The image is an artistic rendering of the study results by team led Dr. Bo Chen, PhD.

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An artist’s rendering incorporates the images of the Müller glia-derived rod photoreceptors. Image credit: Bo Chen, Ph.D.

The initial inspiration for this project came from an observation in zebrafish. These creatures have the remarkable ability to restore vision after severe eye injuries. It turns out that, in response to injury, a type of cell in the eye called Muller glia – which helps maintain the structure and function of the zebrafish retina – transforms into rod photoreceptors, which allow vision in low light.

Now, Muller glia are found in humans and mice too, so the research team sought to harness this shape-shifting, sight-restoring ability of the Muller glia but in the absence of injury. They first injected a gene into the eyes of mice born blind that stimulated the glia cells to divide and grow. Then, to mimic the reprogramming process seen in zebrafish, specific factors were injected to cause the glia to change identity into photoreceptors.

The researchers showed that the glia-derived photoreceptors functioned just like those observed in normal mice and made the right connections with nerve cells responsible for sending visual information to the brain. The team’s next steps are to not only show the cells are functioning properly in the eye and brain but to also do behavioral studies to confirm that the mice can do tasks that require vision.

If these studies pan out, it could lead to a new therapeutic strategy for blinding diseases like retinitis pigmentosa and macular degeneration. Rather than transplanting replacement cells, this treatment approach would spur our own eyes to repair themselves. In the meantime, CIRM-funded researchers have studies currently in clinical trials testing stem cell-based treatments for retinitis pigmentosa and macular degeneration.

A tale of two tails: one regenerates, the other, not quite so much (Kevin McCormack) One of the wonders of nature, well two if you want to be specific, is how both salamanders and lizards are able to regrow their tails if they lose them. But there is a difference. While salamanders can regrow a tail that is almost identical to the original, lizard’s replacements are rather less impressive. Now researchers have found out why.

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In these fluorescence microscopy images, cross sections of original lizard and salamander tails (left) show cartilage (green) and nerve cells (red). In the regenerated tails (right), the lizard’s is made up mostly of cartilage, while the salamander also has developed new nerve cells. Image: Thomas Lozito

The study, published in the Proceedings of the National Academy of Sciences, shows how a lizard’s new tail doesn’t have bone but instead has cartilage, and also lacks nerve cells. The key apparently is the stem cells both use to regenerate the tail. Salamanders use neural stem cells from their spinal cord and turn them into other types of nervous system cell, such as neurons. Lizards neural stem cells are not able to do this.

The researchers, from the University of Pittsburgh, tested their findings by placing neural stem cells from the axolotl salamander into tail stumps from geckos. They noted that, as those tails regrew, some of those transplanted cells turned into neurons.

In an interview in Science News, study co-author Thomas Lozito says the team hope to take those findings and, using the CRISPR/Cas9 gene-editing tool, see if they can regenerate body parts in other animals:

 “My goal is to make the first mouse that can regenerate its tail. We’re kind of using lizards as a stepping-stone.”

Stem cell summer: high school students document internships via social media, Part 2

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Well, just like that, summer vacation is over. Most kids in California are back in school now and probably one of the first questions they’ll ask their friends is, “what did you do this summer?”. For 58 talented high school students, their answer will be, “I became a stem cell scientist.”

Best Instagram Post Award: Mia Grossman

https://www.instagram.com/p/BleQFSFASgQ/?tagged=cirmsparklab

Those students participated in a CIRM-funded internship called the Summer Program to Accelerate Regenerative medicine Knowledge, or SPARK for short, with seven programs throughout Northern and Southern California which include Caltech, Cedars-Sinai, City of Hope, Stanford, UC Davis, UCSF and the UCSF Benioff Children’s Hospital Oakland. Over the course of about 8 eight weeks, the interns gained hands-on training in stem cell research at some of the leading research institutes in California. Last week, they all met for the annual SPARK conference, this year at the UC Davis Betty Irene Moore School of Nursing, to present their research results and to hear from expert scientists and patient advocates.

As part of their curriculum, the students were asked to write a blog and to post Instagram photos (follow #cirmsparklab) to document their internship experiences. Several CIRM team member selected their favorite entries and presented awards to the winning interns at the end of the conference. We featured two of the winners in a blog from last week.

Our two winners featured today are Cedars-Sinai SPARK student, Mia Grossman – a senior at Beverly Hills High School – one of the Instagram Award winners (see her looping video above) and UC Davis SPARK student Anna Guzman – a junior at Sheldon High School – one of the Blog Award winners. Here’s her blog:

The Lab: A Place I Never Thought I’d Be
By Anna Guzman

AnnaGuzman

Anna Guzman

My CIRM SPARK journey started long before I ever stepped foot in the Institute for Regenerative Cures at UC Davis. Instead, my journey started two years earlier, when my older sister came home from the same internship with stories of passaged cells, images of completed western blots, and a spark in her eye when she described the place she had come to love. Barely 14 years old, I listened wide-eyed as my sister told us about the place she disappeared to each morning, stories of quirky professors, lovable mentors, and above all, the brilliant flame that everyone in her lab shared for learning. But even as she told her stories around the dinner table, I imagined this cold place where my charismatic, intelligent, and inquisitive sister was welcomed. I imagined the chilling concentration of dozens of geniuses bent over their work, of tissue culture rooms where every tiny movement was a potential disaster, and above all, of a labyrinth of brilliant discoveries and official sounding words with the door securely locked to 16 year old girls – girls who had no idea what they wanted to do with their life, who couldn’t confidently rattle words like “CRISPR,” “mesenchymal” and “hematopoietic” off their tongues. In short, this wasn’t a place for me.

But somehow I found myself applying for the CIRM SPARK internship. Seconds after I arrived for my first day at the place I was sure I would not belong, I realized how incorrect my initial assumption of the lab was. Instead of the intimidating and sophisticated environment filled with eye-rolling PhDs who scoffed at the naïve questions of a teenager, I found a room filled with some of the kindest, funniest, warmest people I had ever met. I soon found that the lab was a place of laughter and jokes across bays, a place of smiles in the hallways and mentors who tirelessly explained theory after theory until the intoxicating satisfaction of a lightbulb sparked on inside my head. The lab was a place where my wonderful mentor Julie Beegle patiently guided me through tissue culture, gently reminding me again and again how to avoid contamination and never sighing when I bubbled up the hemocytometer, miscalculated transduction rates, or asked question after question after question. Despite being full of incredibly brilliant scholars with prestigious degrees and publications, the lab was a place where I was never made to feel small or uneducated, never made to feel like there was something I couldn’t understand. So for me, the lab became a place where I could unashamedly fuel my need to understand everything, to ask hundreds of questions until the light bulbs sputtered on and a spark, the same spark that had glowed in the eyes of my sister years ago, burned brightly. The lab became a place where it was always okay to ask why.

At moments towards the middle of the internship, when my nerves had dissolved into a foundation of tentative confidence, and I had started to understand the words that tumbled out of my mouth, I’d be working in the biosafety cabinet or reading a protocol to my mentor and think, Wow. That’s Me. That’s me counting colonies and loading gels without the tell-tale nervous quiver of a beginner’s hand. That’s me explaining my project to another intern without an ambiguous question mark marring the end of the sentence. That’s me, pipetting and centrifuging and talking and understanding – doing all the things that I was certain that I would never be able to do. That’s the best thing that the CIRM SPARK internship has taught me. Being an intern in this wonderful place with these amazing people has taught me to be assured in my knowledge, unashamed in my pursuit of the answer, and confident in my belief that maybe I belong here. These feelings will stay with me as I navigate the next two years of high school and the beginning of the rest of my life. I have no doubt that I will feel unsure again, that I will question whether I belong and wonder if I am enough. But then I will remember how I felt here, confident, and unashamed, and assured in the place where I never thought I’d be.

It was not until the end of my internship, as I stood up to present a journal article to a collection of the very people who had once terrified me, that I realized the biggest thing I was wrong about two years ago. I was wrong when I assumed that this was a place where I would never belong. Instead, as I stood in front of this community of amazingly brilliant and kind people, my mouth forming words that I couldn’t have dreamed of understanding a month ago, I realized that this was precisely where I belonged. This was the place for me.

Stem Cell Roundup: Knowing the nose, stem cell stress and cell fate math.

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The Stem Cellar’s Image of the Week.
Our favorite image this week, comes to us from researchers at Washington University School of Medicine in St. Louis. Looking like a psychedelic Rorschach test, the fluorescence microscopy depicts mouse olfactory epithelium (in green), a sheet of tissue that develops in the nose. The team identified a new stem cell type that controls the growth of this tissue. New insights from the study of these cells could help the team better understand why some animals, like dogs, have a far superior sense of smell than humans.

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Peering into the nasal cavity of a mouse. Olfactory epithelium is indicated by green. Image credit: Lu Yang, Washington University School of Medicine in St. Louis.

A Washington U. press release provides more details about this fascinating study which appears in Developmental Cell.

How stress affects blood-forming stem cells.
Stress affects all of us in different ways. Some people handle it well. Some crack up and become nervous wrecks. So, perhaps it shouldn’t come as a huge surprise that stress also affects some stem cells. What is a pleasant surprise is that knowing this could help people undergoing cancer therapy or bone marrow transplants.

First a bit of background. Hematopoietic, or blood-forming stem cells (HSCs) come from bone marrow and are supported by other cells that secrete growth factors, including one called pleiotrophin or PTN. While researchers knew PTN was present in bone marrow they weren’t sure precisely what role it played.

So, researchers at UCLA set out to discover what PTN did.

In a CIRM-funded study they took mice that lacked PTN in endothelial cells – these line the blood vessels – or in their stromal cells – which make up the connective tissue. They found that a lack of PTN in stromal cells caused a lack of blood stem cells, but a lack of PTN in endothelial cells had no impact.

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Expression of pleiotrophin (green) in bone marrow blood vessels (red) and stromal cells (white) is shown in normal mice (left) and in mice at 24 hours following irradiation (right). Image credit: UCLA

However, as Dr. John Chute explained in a news release, when they stressed the cells, by exposing them to radiation, they found something very different:

“The surprising finding was that pleiotrophin from stromal cells was not necessary for blood stem cell regeneration following irradiation — but pleiotrophin from endothelial cells was necessary.”

In other words, during normal times the stem cells rely on PTN from stromal cells, but after stress they depend on PTN from endothelial cells.

Dr. Chute says, because treatments like chemotherapy and radiation deplete bone marrow stem cells, this finding could have real-world implications for patients.

“These therapies for cancer patients suppress our blood cell systems over time. It may be possible to administer modified, recombinant versions of pleiotrophin to patients to accelerate blood cell regeneration. This strategy also may apply to patients undergoing bone marrow transplants.”

The study appears in the journal Cell Stem Cell.

Predicting the fate of cells with math
Researchers at Harvard Medical School and the Karolinska Institutet in Sweden reported this week that they have devised a mathematical model that can predict the fate of stem cells in the brain.

It may sound like science-fiction but the accomplished the feat by tracking changes in messenger RNA (mRNA), the genetic molecule that translates our DNA code into instructions for building proteins. As a brain stem cell begins specializing into specific cell types, hundreds of genes get turns on and off, which is observed by the rate of changes in mRNA productions.

The team built their predictive model by measuring these changes. In a press release, co-senior author, Harvard professor Peter Kharchenko, described this process using a great analogy:

“Estimating RNA velocity—or the rate of RNA change over time—is akin to observing the cooks in a restaurant kitchen as they line up the ingredients to figure out what dishes they’ll be serving up next.”

The team verified their mathematical model by inputting other data that was not use in constructing the model. Karolinkska Institutet professor, Sten Linnarsson, the other co-senior author on the study, described how such a model could be applied to human biomedical research:

“RNA velocity shows in detail how neurons and other cells acquire their specific functions as the brain develops and matures. We’re especially excited that this new method promises to help reveal how brains normally develop, but also to provide clues as to what goes wrong in human disorders of brain development, such as schizophrenia and autism.”

The study appears in the journal Nature.

Stem cell summer: high school students document internships via social media, Part 1

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My fellow CIRM team members and I just got back from two days in Sacramento where we attended one of our favorite annual events: the CIRM SPARK Student Conference. SPARK, which is short for Summer Program to Accelerate Regenerative medicine Knowledge, is a CIRM-funded education program that offers California High School students an invaluable opportunity to gain hands-on training in stem cell research at some of the leading research institutes in California.

This meeting represents the culmination of the students’ internships in the lab this summer and gives each student the chance to present their project results and to hear from stem cell research experts and patient advocates. Every summer, without fail, I’m blown away by how much the students accomplish in such a short period of time and by the poise and clarity with which they describe their work. This year was no exception.

Best Instagram Post Award: Skyler Wong

To document the students’ internship experiences, we include a social media curriculum to the program. Each student posts Instagram photos and writes a blog essay describing their time in the lab. Members of the CIRM team reviewed and judged the Instagram posts and blogs. It was a very difficult job selecting only three Instagrams out of over 400 (follow them at #cirmsparklab) that were posted over the past eight weeks. Equally hard was choosing three blogs from the 58 student essays which seem to get better in quality each year.

Over the next week or so, we’re going to feature the three Instagram posts and three blogs that were ultimately awarded. Our two winners featured today are UC Davis SPARK student, Skyler Wong, a rising senior at Sheldon High School was one of the Instagram Award winners (see his photo above) and Stanford SPARK student Angelina Quint, a rising senior at Redondo Union High School, was one of the Blog Award winners. Here’s her blog:

Best Blog Award:
My SPARK 2018 summer stem cell research internship experience
By Angelina Quint

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Angelina Quint

Being from Los Angeles, I began the SIMR program as a foreigner to the Bay Area. As my first research experience, I was even more so a foreigner to a laboratory setting and the high-tech equipment that seemingly occupied every edge and surface of Stanford’s Lorry I. Lokey Stem Cell building. Upon first stepping foot into my lab at the beginning of the summer, an endless loop of questions ran through my brain as I ventured deeper into this new, unfamiliar realm of science. Although excited, I felt miniscule in the face of my surroundings—small compared to the complexity of work that laid before me. Nonetheless, I was ready to delve deep into the unknown, to explore this new world of discovery that I had unlocked.

Participating in the CIRM research program, I was given the extraordinary opportunity to pursue my quest for knowledge and understanding. With every individual I met and every research project that I learned about, I became more invigorated to investigate and discover answers to the questions that filled my mind. I was in awe of the energy in the atmosphere around me—one that buzzed with the drive and dedication to discover new avenues of thought and complexity. And as I learned more about stem cell biology, I only grew more and more fascinated by the phenomenon. Through various classes taught by experts in their fields on topics spanning from lab techniques to bone marrow transplants, I learned the seemingly limitless potential of stem cell research. With that, I couldn’t help but correlate this potential to my own research; anything seemed possible.

However, the journey proved to be painstakingly arduous. I soon discovered that a groundbreaking cure or scientific discovery would not come quickly nor easily. I faced roadblocks daily, whether it be in the form of failed gel experiments or the time pressures that came with counting colonies. But to each I learned, and to each I adapted and persevered. I spent countless hours reading papers and searching for online articles. My curiosity only grew deeper with every paper I read—as did my understanding. And after bombarding my incredibly patient mentors with an infinite number of questions and thoughts and ideas, I finally began to understand the scope and purpose of my research. I learned that the reward of research is not the prestige of discovering the next groundbreaking cure, but rather the knowledge that perseverance in the face of obstacles could one day transform peoples’ lives for the better.

As I look back on my journey, I am filled with gratitude for the lessons that I have learned and for the unforgettable memories that I have created. I am eternally grateful to my mentors, Yohei and Esmond, for their guidance and support along the way. Inevitably, the future of science is uncertain. But one thing is always guaranteed: the constant, unhindered exchange of knowledge, ideas, and discovery between colleagues passionate about making a positive difference in the lives of others. Like a stem cell, I now feel limitless in my ability to expand my horizons and contribute to something greater and beyond myself. Armed with the knowledge and experiences that I have gained through my research, I aspire to share with others in my hometown the beauty of scientific discovery, just as my mentors have shared with me. But most of all, I hope that through my continued research, I can persist in fighting for new ways to help people overcome the health-related challenges at the forefront of our society.

 

The Five Types of Stem Cells

/ Todd Dubnicoff / 3 Comments

When I give an “Intro to Stem Cells” presentation to, say, high school students or to a local Rotary Club, I begin by explaining that there are three main types of stem cells: (1) embryonic stem cells (ESCs) (2) adult stem cells and (3) induced pluripotent stem cells (iPSCs). Well, like most things in science, it’s actually not that simple.

To delve a little deeper into the details of characterizing stem cells, I recommend checking out a video animation produced by BioInformant, a stem cell market research company. The video is introduced in a blog, “Do you know the 5 types of stem cells?” by Cade Hildreth, BioInformant’s founder and president.

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Image credit: BioInformant

Hildreth’s list categorizes stem cells by the extent of each type’s shape-shifting abilities. So while we sometimes place ESCs and iPSCs in different buckets because the methods for obtaining them are very different, in this list, they both belong to the pluripotent stem cell type. Pluri (“many”) – potent (“potential”) refers to the ability of both stem cell types to specialize into all of the cell types in the body. They can’t, though, make the cells of the placenta and other extra-embryonic cells too. Those ultimate blank-slate stem cells are called toti (“total”) – potent (“potential”).

When it comes to describing adult stem cells in my talks, I often lump blood stem cells together with muscle stem cells because they are stem cells that are present within us throughout life. But based on their ability to mature into specialized cells, these two stem cell types fall into two different categories in Hildreth’s list:  blood stem cells which can specialize into closely related cell types – the various cell types found in the blood – are considered “oligopotent” while muscle stem cells are “unipotent” because the can only mature into one type of cell, a muscle cell.

For more details on the five types of stem cells based on their potential to specialize, head over to the BioInformant blog. And scroll to the very bottom for the video animation which can also viewed on FaceBook.

Stem Cell Roundup: Artificial Embryos to Study Miscarriage and ALS Insight – Muscle Repair Cells Go Rogue

/ Todd Dubnicoff / 2 Comments

Stem Cell Image of the Week: Artificial embryos for studying miscarriage (Adonica Shaw)

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Mouse embryos artificially generated by combining three types of stem cells.
Image: University of Cambridge.

This week’s stem cell image of the week comes from a team of researchers from The University of Cambridge who published research in Nature Cell Biology earlier this week indicating they’d achieved a breakthrough in stem cell research that resulted in the generation of a key developmental step that’d never before been achieved when trying to generate an artificial embryo.

To create the artificial embryo, the scientists combined mouse embryonic stem cells with two other types of stem cells that are present in the very earliest stages of embryo development. The reseachers grew the three stem cell types into a dish and coaxed them into simulating a process called gastrulation – one of the very first events that happens during a creature’s development in which the early embryo begins reorganizing into more and more complex multilayer organ structures.

In an interview with The Next Web (TNW), Professor Magdalena Zernicka-Goetz, who led the research team, says:

”Our artificial embryos underwent the most important event in life in the culture dish. They are now extremely close to real embryos. To develop further, they would have to implant into the body of the mother or an artificial placenta.”

The goal of this research isn’t to create mice on demand. Its purpose is to gain insights into early life development. And that could lead to a giant leap in our understanding of what happens during the period in a woman’s pregnancy where the risk of miscarriage is highest.

According to professor Zernicka-Goetz,

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Magdalena Zernicka-Goetz, PhD

“We can also now try to apply this to the equivalent human stem cell types and so study the very earliest events in human embryo development without actually having to use natural human embryos.The early stages of embryo development are when a large proportion of pregnancies are lost and yet it is a stage that we know very little about. Now we have a way of simulating embryonic development in the culture dish, so it should be possible to understand exactly what is going on during this remarkable period in an embryo’s life, and why sometimes this process fails.”

Muscle repair cells go rogue – a possible drug target for ALS?
Call it a case of a good cell gone bad. This week researchers at Sanford Burnham Prebys Medical Discovery Institute, report in Nature Cell Biology that fibro-adipogenic progenitors (FAPs) – cells that are critical in coordinating the repair of torn muscles – can turn rogue, causing muscles to wither and scar. This “Dr. Jekyl and Mr. Hype” discovery may lead to novel treatments for a number of incurable disorders like amyotrophic lateral sclerosis (ALS), spinal muscular atrophy (SMA) and spinal cord injury.

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Senior author Pier Lorenzo Puri, M.D. (right) and co-first author Luca Madaro, Ph.D. Credit: Fondazione Santa Lucia IRCCS

When muscle is strained, whether due to an acute injury or even weight-lighting, a consistent order of events occurs within the muscle. FAB cells enter the muscle tissue after immune cells called macrophages come in and gobble up dead tissue but before muscle stem cells are stimulated to regenerate the lost muscle. However, to the researchers’ surprise, something entirely different happens in the case of neuromuscular disorders like ALS where nerve signal connections to the muscles degenerate.

Once nerves are no longer attached to muscle and stop sending movement signals from the brain, the macrophages don’t infiltrate the muscle and instead the FAPs pile up in the muscle and never leave. And as a result, muscle stem cells are never activated. In ALS patients, this cellular train crash leads to progressive loss of muscle control to move the limbs and ultimately even to breathe.

The promising news from these findings, which were funded in part by CIRM, is that the team identified of an out-of-whack cell signaling pathway that is responsible for the breakdown in the rogue function of the FAP cells. The researchers hope further studies of this pathway’s role in muscle degeneration may lead to novel therapies and disease-screening technologies for ALS and other motor neuron diseases.