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

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).

CIRMFaceBookLiveIcon4BeliveTV_v2

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.

  • Walters_Mark_200x250

    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.

  • e90e6-adrienneshapiro

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

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.

AnthonyTan

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

genniferhom

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

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

Angelina2

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.

 

Research Targeting Prostate Cancer Gets Almost $4 Million Support from CIRM

Prostate cancer

A program hoping to supercharge a patient’s own immune system cells to attack and kill a treatment resistant form of prostate cancer was today awarded $3.99 million by the governing Board of the California Institute for Regenerative Medicine (CIRM)

In the U.S., prostate cancer is the second most common cause of cancer deaths in men.  An estimated 170,000 new cases are diagnosed each year and over 29,000 deaths are estimated in 2018.  Early stage prostate cancer is usually managed by surgery, radiation and/or hormone therapy. However, for men diagnosed with castrate-resistant metastatic prostate cancer (CRPC) these treatments often fail to work and the disease eventually proves fatal.

Poseida Therapeutics will be funded by CIRM to develop genetically engineered chimeric antigen receptor T cells (CAR-T) to treat metastatic CRPC. In cancer, there is a breakdown in the natural ability of immune T-cells to survey the body and recognize, bind to and kill cancerous cells. Poseida is engineering T cells and T memory stem cells to express a chimeric antigen receptor that arms these cells to more efficiently target, bind to and destroy the cancer cell. Millions of these cells are then grown in the laboratory and then re-infused into the patient. The CAR-T memory stem cells have the potential to persist long-term and kill residual cancer calls.

“This is a promising approach to an incurable disease where patients have few options,” says Maria T. Millan, M.D., President and CEO of CIRM. “The use of chimeric antigen receptor engineered T cells has led to impressive results in blood malignancies and a natural extension of this promising approach is to tackle currently untreatable solid malignancies, such as castrate resistant metastatic prostate cancer. CIRM is pleased to partner on this program and to add it to its portfolio that involves CAR T memory stem cells.”

Poseida Therapeutics plans to use the funding to complete the late-stage testing needed to apply to the Food and Drug Administration for the go-ahead to start a clinical trial in people.

Quest Awards

The CIRM Board also voted to approve investing $10 million for eight projects under its Discovery Quest Program. The Quest program promotes the discovery of promising new stem cell-based technologies that will be ready to move to the next level, the translational category, within two years, with an ultimate goal of improving patient care.

Among those approved for funding are:

  • Eric Adler at UC San Diego is using genetically modified blood stem cells to treat Danon Disease, a rare and fatal condition that affects the heart
  • Li Gan at the Gladstone Institutes will use induced pluripotent stem cells to develop a therapy for a familial form of dementia
  • Saul Priceman at City of Hope will use CAR-T therapy to develop a treatment for recurrent ovarian cancer

Because the amount of funding for the recommended applications exceeded the money set aside, the Application Subcommittee voted to approve partial funding for two projects, DISC2-11192 and DISC2-11109 and to recommend, at the next full Board meeting in October, that the projects get the remainder of the funds needed to complete their research.

The successful applications are:

 

APPLICATION

 

TITLE

 

INSTITUTION

CIRM COMMITTED FUNDING
DISC2-11131 Genetically Modified Hematopoietic Stem Cells for the

Treatment of Danon Disease

 

 

U.C San Diego

 

$1,393,200

 

DISC2-11157 Preclinical Development of An HSC-Engineered Off-

The-Shelf iNKT Cell Therapy for Cancer

 

 

U.C. Los Angeles

 

$1,404,000

DISC2-11036 Non-viral reprogramming of the endogenous TCRα

locus to direct stem memory T cells against shared

neoantigens in malignant gliomas

 

 

U.C. San Francisco

 

$900,000

DISC2-11175 Therapeutic immune tolerant human islet-like

organoids (HILOs) for Type 1 Diabetes

 

 

Salk Institute

 

$1,637,209

DISC2-11107 Chimeric Antigen Receptor-Engineered Stem/Memory

T Cells for the Treatment of Recurrent Ovarian Cancer

 

 

City of Hope

 

$1,381,104

DISC2-11165 Develop iPSC-derived microglia to treat progranulin-

deficient Frontotemporal Dementia

 

 

Gladstone Institutes

 

$1,553,923

DISC2-11192 Mesenchymal stem cell extracellular vesicles as

therapy for pulmonary fibrosis

 

 

U.C. San Diego

 

$865,282

DISC2-11109 Regenerative Thymic Tissues as Curative Cell

Therapy for Patients with 22q11 Deletion Syndrome

 

 

Stanford University

 

$865,282

 

 

“Junk” DNA is development gold for the dividing embryo

Single-two-cell-mouse-embryos-with-nuclear-LINE1-RNA-labeled-magenta-Credit-Ramalho-Santos-lab_1

Single two-cell mouse embryos with nuclear LINE1 RNA labeled magenta – Credit Ramalho-Santos lab

The DNA in our cells provide the instructions to make proteins, the workhorses of our body. Yet less than 2% of the 3 billion base pairs (the structural units of DNA) in each of our cells are actually involved in protein production. The rest, termed non-coding DNA for not being involved in protein production, has roles in regulating genetic activity, but, largely, these genetic regions have remained a mystery causing some to mis-characterize it as “junk” DNA.

One of the largest components of these “junk” DNA regions are transposons, which make up 50% of the genome. Transposons are variable length DNA segments that are able to duplicate and re-insert themselves into different locations of the genome which is why they’re often called “jumping genes”.

Transposons have been implicated in diseases like cancer because of their ability to disrupt normal gene function depending on where the transposon inserts itself. Now, a CIRM-funded study in Miguel Ramalho-Santos’ laboratory at UCSF has found a developmental function for transposons in the dividing embryo. The report was published today in the Journal Cell.

Of the transposons identified in humans, LINE1 is the most common, composing 24% of the entire human genome. Many investigators in the field had observed that LINE1 is highly expressed in embryonic stem cells, which seemed paradoxical given that these pieces of DNA were previously thought to be either inert or harmful. Because this DNA was present at such high levels, the investigators decided to eliminate it from fertilized mouse embryos at the two-cell stage and observe how this affected development.

To their surprise, they found that the embryo was not able to progress beyond this stage. Further investigation revealed that LINE1, along with other proteins, is responsible for turning off the genetic program that maintains the two-cell state, thus allowing the embryo to further divide and develop.

Dr. Ramalho-Santos believes that this is a fine-tuned mechanism to ensure that the early stages of develop progress successfully. Because there are so many copies of LINE1 in the genome, even if one is not functional, it is likely that there will be functional back up, an important factor in ensuring early mistakes in embryo development do not occur.

In a press release, Dr. Ramalho-Santos states:

“We now think these early embryos are playing with fire but in a very calculated way. This could be a very robust mechanism for regulating development…I’m personally excited to continue exploring novel functions of these elements in development and disease.”

CIRM funded study results in the first ever in utero stem cell transplant to treat alpha thalassemia

Mackenzie

Dr. Tippi MacKenzie (left) of UCSF Benioff Children’s Hospital San Francisco, visits with newborn Elianna and parents Nichelle Obar and Chris Constantino. Photo by Noah Berger

Imagine being able to cure a genetic disorder before a baby is even born. Thanks to a CIRM funded study, what would have been a mere dream a couple of years ago has become a reality.

Drs. Tippi MacKenzie and Juan Gonzalez Velez of the University of California San Francisco (UCSF) have successfully treated alpha thalassemia in Elianna Constantino, using stem cells from her mother’s bone marrow. Alpha thalassemia is part of a group of blood disorders that impairs the body’s ability to produce hemoglobin, the molecule that is responsible for transporting oxygen throughout the body on red blood cells. Present in approximately 5% of the population, alpha thalassemia is particularly prevalent among individuals of Asian heritage. Treatment options for this disease are severely limited, generally requiring multiple rounds of blood transfusions or a bone marrow transplant which requires immunosuppressive therapy. Normally, fetuses die in the womb or the pregnancy is aborted because of the poor prognosis.

The revolutionary treatment pioneered at UCSF involved isolating blood stem cells (cells that are capable of turning into all blood cell types) from the mother’s bone marrow and injecting these cells into Elianna’s bloodstream via the umbilical vein. The doctors were able to observe the development of healthy blood cells in the baby’s blood stream, allowing for efficient oxygen transport throughout the baby’s body. Because the cells were transplanted at the fetal stage, a time when the immune system is not fully developed, there was low risk of rejection and the transplant occurred without aggressive immunosuppressive therapy.

The baby was born healthy earlier this year and has been allowed to return home. While it is still too early to tell how effective this treatment will be in the long term, it is very encouraging that both the mother and baby have endured the treatment thus far.

In a press release, Dr. MacKenzie states:

“Her healthy birth suggests that fetal therapy is a viable option to offer to families with this diagnosis.”

The in utero stem cell transplant was performed as part of a clinical trial conducted at the UCSF Benioff Children’s Hospitals in San Francisco and Oakland. The trial is currently enrolling 10 pregnant women to test the safety and effectiveness of this treatment over a wider population.

If successful, this type of treatment is particularly exciting because it could be expanded to other types of hereditary blood disorders such as sickle cell anemia and hemophilia.

 

 

 

Friday Stem Cell Round: Ask the Expert Facebook Live, Old Brain Cells Reveal Insights and Synthetic Development

Stem Cell Photo of the Week: We’re Live on Facebook Live!

Our stem cell photo of the week is a screenshot from yesterday’s Facebook Live event: “Ask the Expert: Stem Cells and Stroke”. It was our first foray into Facebook Live and, dare I say, it was a success with over 150 comments and 4,500 views during the live broadcast.

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Screen shot of yesterday’s Facebook Live event. Panelists included (from top left going clockwise): Sonia Coontz, Kevin McCormack, Gary Steinberg, MD, PhD and Lila Collins, PhD.

Our panel included Dr. Gary Steinberg, MD, PhD, the Chair of Neurosurgery at Stanford University, who talked about promising clinical trial results testing a stem cell-based treatment for stroke. Lila Collins, PhD, a Senior Science Officer here at CIRM, provided a big picture overview of the latest progress in stem cell therapies for stroke. Sonia Coontz, a patient of Dr. Steinberg’s, also joined the live broadcast. She suffered a devastating stroke several years ago and made a remarkable recovery after getting a stem cell therapy. She had an amazing story to tell. And Kevin McCormack, CIRM’s Senior Director of Public Communications, moderated the discussion.

Did you miss the Facebook Live event? Not to worry. You can watch it on-demand on our Facebook Page.

What other disease areas would you like us to discuss? We plan to have these Ask the Expert shows on a regular basis so let us know by commenting here or emailing us at info@cirm.ca.gov!

Brain cells’ energy “factories” may be to blame for age-related disease

Salk Institute researchers published results this week that shed new light on why the brains of older individuals may be more prone to neurodegenerative diseases like Parkinson’s and Alzheimer’s. To make this discovery, the team applied a technique they devised back in 2015 which directly converts skin cells into brain cells, aka neurons. The method skips the typical intermediate step of reprogramming the skin cells into induced pluripotent stem cells (iPSCs).

They collected skin samples from people ranging in age from 0 to 89 and generated neurons from each. With these cells in hand, the researchers then examined how increased age affects the neurons’ mitochondria, the structures responsible for producing a cell’s energy needs. Previous studies have shown a connection between faulty mitochondria and age-related disease.

While the age of the skin cells had no bearing on the health of the mitochondria, it was a different story once they were converted into neurons. The mitochondria in neurons derived from older individuals clearly showed signs of deterioration and produced less energy.

Aged-mitochondria-green-in-old-neurons-gray-appear-mostly-as-small-punctate-dots-rather-than-a-large-interconnected-network-300x301

Aged mitochondria (green) in old neurons (gray) appear mostly as small punctate dots rather than a large interconnected network. Credit: Salk Institute.

The researchers think this stark difference in the impact of age on skin cells vs. neurons may occur because neurons have higher energy needs. So, the effects of old age on mitochondria only become apparent in the neurons. In a press release, Salk scientist Jerome Mertens explained the result using a great analogy:

“If you have an old car with a bad engine that sits in your garage every day, it doesn’t matter. But if you’re commuting with that car, the engine becomes a big problem.”

The team is now eager to use this method to examine mitochondrial function in neurons derived from Alzheimer’s and Parkinson’s patient skin samples and compared them with skin-derived neurons from similarly-aged, healthy individuals.

The study, funded in part by CIRM, was published in Cell Reports.

“Synthetically” Programming embryo development

One of the most intriguing, most fundamental questions in biology is how an embryo, basically a non-descript ball of cells, turns into a complex animal with eyes, a brain, a heart, etc. A deep understanding of this process will help researchers who aim to rebuild damaged or diseased organs for patients in need.

3-layer_1.16.9

Researchers programmed cells to self-assemble into complex structures such as this one with three differently colored layers. Credit: Wendell Lim/UCSF

A fascinating report published this week describes a system that allows researchers to program cells to self-organize into three-dimensional structures that mimic those seen during early development. The study applied a customizable, synthetic signaling molecule called synNotch developed in the Wendell Lim’s UCSF lab by co-author Kole Roybal, PhD, now an assistant professor of microbiology and immunology at UCSF, and Leonardo Morsut, PhD, now an assistant professor of stem cell biology and regenerative medicine at the University of Southern California.

A UCSF press release by Nick Weiler describes how synNotch was used:

“The researchers engineered cells to respond to specific signals from neighboring cells by producing Velcro-like adhesion molecules called cadherins as well as fluorescent marker proteins. Remarkably, just a few simple forms of collective cell communication were sufficient to cause ensembles of cells to change color and self-organize into multi-layered structures akin to simple organisms or developing tissues.”

Senior author Wendell Lim also explained how this system could overcome the challenges facing those aiming to build organs via 3D bioprinting technologies:

“People talk about 3D-printing organs, but that is really quite different from how biology builds tissues. Imagine if you had to build a human by meticulously placing every cell just where it needs to be and gluing it in place. It’s equally hard to imagine how you would print a complete organ, then make sure it was hooked up properly to the bloodstream and the rest of the body. The beauty of self-organizing systems is that they are autonomous and compactly encoded. You put in one or a few cells, and they grow and organize, taking care of the microscopic details themselves.”

Study was published in Science.

CCSF’s CIRM Bridges scholars: the future of stem cell research is in good hands

In need of an extra dose of inspiration? You might read a great book or listen to that podcast your friend recommended. You might even take a stroll along the beach. But I can do you one better: go to a conference poster session where young stem cell scientists describe their research.

That’s what I did last week at the City College of San Francisco’s (CCSF) Bioscience Symposium held at UC San Francisco’s Genentech Hall. It’s a day-long conference that showcases the work of CCSF Bioscience interns and gives them a chance to present the results of their research projects, network with their peers and researchers, hear panelists talk about careers in biotechnology and participate in practice job interviews.

Bridges_CCSF_2018b

CCSF’s CIRM Bridges Scholars (clockwise from top left): Vanessa Lynn Herrara, Viktoriia Volobuieva, Christopher Nosworthy and Sofiana E. Hamama.

Bridges_CCSF_2018

CCSF’s CIRM Bridges Scholars (clockwise from top left): Seema Niddapu, Mark Koontz, Karolina Kaminska and Iris Avellano

Eight of the dozens of students in attendance at the Symposium are part of the CIRM-funded Bridges Stem Cell Internship program at CCSF. It’s one of 14 CIRM Bridges programs throughout the state that provides paid stem cell research internships to students at universities and colleges that don’t have major stem cell research programs. Each Bridges internship includes thorough hands-on training and education in stem cell research, and direct patient engagement and outreach activities that engage California’s diverse communities.

In the CCSF Bridges Program, directed by Dr. Carin Zimmerman, the students do a 9-month paid internship in top notch labs at UCSF, the Gladstone Institutes and Blood System Research Institute. As I walked from poster to poster and chatted with each Bridges scholar, their excitement and enthusiasm for carrying out stem cell research was plain to see. It left me with the feeling that the future of stem cell research is in good hands and, as I walked into the CIRM office the next day, I felt re-energized to tackle the Agency’s mission to accelerate stem cell treatment for patients with unmet medical needs. But don’t take my word for it, listen to the enthusiastic perspectives of Bridges scholars Mark Koontz and Iris Avellano in this short video.

Livers skip stem cells, build missing structures from scratch via direct cell identity conversion

Stem cells…eh, who needs them anyway?!

That’s what you might be thinking after today, at least for some forms of liver disease. That’s because a team of researchers from UCSF and Cincinnati Children’s Hospital Medical Center just published results in Nature showing liver cells can directly change identity, or transdifferentiate, in order to build, from scratch, structures missing due to disease.

nci-vol-10440-72

The liver contains a network of tubes called bile ducts that carry fat-digesting bile to the small intestine via the gallbladder.
Image: National Cancer Inst.

The extraordinary regenerative power of the liver in animals is well-documented. A human liver, for instance, can fully regrow from just 25% of its original mass. That’s thanks to the hepatocyte, the main type of liver cell, that has the ability to replenish pre-existing tissue lost due to disease or injury. What hasn’t been as clear cut, is whether the hepatocyte has the capacity to change identity and build functional liver structures from scratch that never developed in the first place due to genetic disorders.

To examine that possibility, the study – funded in part by CIRM – focused on an inherited liver disease called Alagille syndrome which is caused by abnormal bile ducts. Produced by the liver, bile helps digest fats in our diet. It travels from the liver via bile ducts – tree branch-like tube structures in the liver – to the gallbladder, where it’s stored before moving on to the small intestine. In Alagille syndrome, the bile ducts are fewer in number, narrower in size or altogether missing. As a result, the bile builds up in the liver causing scarring and severe damage. Nearly half of all those with Alagille syndrome, require a liver transplant, usually in childhood.

The research team mimicked the symptoms of Alagille syndrome in mice by genetically engineering the animals to lack cholangiocytes, the cells that form bile ducts. Sure enough, liver damage from bile buildup was observed in these mice at birth due to the missing bile duct structures, also called the biliary tree. However, 90% of the mice survived and eventually formed a functional biliary tree. The team went on to show, for the first time, that the hepatocytes had converted en masse into cholangiocytes and created the wholly new bile ducts.

liver cell switching

Mice that mimic Alagille syndrome are born without the branches of the biliary tree, an important “plumbing system” in the liver (A), but show a near-normal biliary system as adults (B). To build the missing branches, liver cells switch identity and form tubes, shown in green, that connect to the trunk of the biliary tree, shown in blue (C). Image: Cincinnati Children’s

The underlying molecular mechanisms of this process were further examined. The researchers showed that the lack of a particular gene activity pathway due to the absence of cholangiocytes during development causes a replacement pathway, stimulated by a protein called TGF-beta, to kick into gear. As a result, the hepatocytes convert into cholangiocytes and form bile ducts. To make a direct connection with the human form of the disease, the researchers found evidence that TGF-beta is active in the liver samples of some patients but not in the livers from healthy individuals.

With this Alagille syndrome mouse model in hand, the researchers want to identify which transcription factors – proteins that bind DNA and regulate gene activity – are involved in changing the liver cells into bile duct cells. Holger Willenbring, MD, PhD, a senior author and CIRM grantee, explained the rationale behind this approach in a press release:

willenbring photo

Holger Willenbring

“Using transcription factors to make bile ducts from hepatocytes has potential as a safe and effective therapy. With our finding that an entire biliary system can be ‘retrofitted’ in the mouse liver, I am encouraged that this eventually will work in patients.”

So rather than developing a stem cell-based therapy in the lab which is then transplanted into a patient, this approach would rely on stimulating the regenerative capacity of liver cells that are already inside the body. And if it eventually works in patients with Alagille syndrome, which only affects 1 in 30,000, it’s possible it could be applied to other liver diseases as well.

Therapies Targeting Cancer, Deadly Immune Disorder and Life-Threatening Blood Condition Get Almost $32 Million Boost from CIRM Board

An innovative therapy that uses a patient’s own immune system to attack cancer stem cells is one of three new clinical trials approved for funding by CIRM’s Governing Board.

Researchers at the Stanford University School of Medicine were awarded $11.9 million to test their Chimeric Antigen Receptor (CAR) T Cell Therapy in patients with B cell leukemias who have relapsed or are not responding after standard treatments, such as chemotherapy.CDR774647-750Researchers take a patient’s own T cells (a type of immune cell) and genetically re-engineer them to recognize two target proteins on the surface of cancer cells, triggering their destruction. In addition, some of the T cells will form memory stem cells that will survive for years and continue to survey the body, killing any new or surviving cancer cells.

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Maria T. Millan

“When a patient is told that their cancer has returned it can be devastating news,” says Maria T. Millan, MD, President & CEO of CIRM. “CAR T cell therapy is an exciting and promising new approach that offers us a way to help patients fight back against a relapse, using their own cells to target and destroy the cancer.”

 

 

Sangamo-logoThe CIRM Board also approved $8 million for Sangamo Therapeutics, Inc. to test a new therapy for beta-thalassemia, a severe form of anemia (lack of healthy red blood cells) caused by mutations in the beta hemoglobin gene. Patients with this genetic disorder require frequent blood transfusions for survival and have a life expectancy of only 30-50 years. The Sangamo team will take a patient’s own blood stem cells and, using a gene-editing technology called zinc finger nuclease (ZFN), turn on a different hemoglobin gene (gamma hemoglobin) that can functionally substitute for the mutant gene. The modified blood stem cells will be given back to the patient, where they will give rise to functional red blood cells, and potentially eliminate the need for chronic transfusions and its associated complications.

UCSFvs1_bl_a_master_brand@2xThe third clinical trial approved is a $12 million grant to UC San Francisco for a treatment to restore the defective immune system of children born with severe combined immunodeficiency (SCID), a genetic blood disorder in which even a mild infection can be fatal. This condition is also called “bubble baby disease” because in the past children were kept inside sterile plastic bubbles to protect them from infection. This trial will focus on SCID patients who have mutations in a gene called Artemis, the most difficult form of SCID to treat using a standard bone marrow transplant from a healthy donor. The team will genetically modify the patient’s own blood stem cells with a functional copy of Artemis, with the goal of creating a functional immune system.

CIRM has funded two other clinical trials targeting different approaches to different forms of SCID. In one, carried out by UCLA and Orchard Therapeutics, 50 children have been treated and all 50 are considered functionally cured.

This brings the number of clinical trials funded by CIRM to 48, 42 of which are active. There are 11 other projects in the clinical trial stage where CIRM funded the early stage research.