Telomere length matters: scientists find shorter telomeres may cause aging-related disease

Aging is inevitable no matter how much you exercise, sleep or eat healthy. There is no magic pill or supplement that can thwart growing older. However, preventing certain age-related diseases is a different story. Genetic mutations can raise the risk of acquiring age-related diseases like heart disease, diabetes, cancer and dementia. And scientists are on the hunt for treatments that target these mutations in hopes of preventing these diseases from happening.

Telomeres shown in white act as protective caps at the ends of chromosomes.

Another genetic component that can accelerate diseases of aging are telomeres. These are caps made up of repeat sequences of DNA that sit at the ends of chromosomes and prevent the loss of important genetic material housed within chromosomes. Healthy cells have long telomeres, and ascells divide these telomeres begin to shorten. If telomere shortening is left unchecked, cells become unhealthy and either stop growing or self-destruct.

Cells have machinery to regrow their telomeres, but in most cases, the machinery isn’t activated and over time, the resulting shortened telomeres can lead to problems like an impaired immune system and organ degeneration. Shortened telomeres are associated with age-related diseases, but the reasons why have remained elusive until recently.

Scientists from the Gladstone Institutes have found a clue to this telomere puzzle that they shared in a study published yesterday in the Journal of Clinical Investigation. This research was funded in part by a CIRM Discovery stage award.

In their study, the team found that mice with a mutation that causes a heart condition known as calcific aortic valve disease (CAVD) were more likely to get the disease if they had short telomeres. CAVD causes the heart valves and vessels to turn hard as rock due to a buildup of calcium. It’s the third leading cause of heart disease and the only effective treatment requires surgery to replace the calcified parts of the heart.

Old age and mutations in one of the copies of the NOTCH1 gene can cause CAVD in humans. However, attempts to model CAVD in mice using the same NOTCH1 mutation have failed to produce symptoms of the disease. The team at Gladstone knew that mice inherently have longer telomeres than humans and hypothesized that these longer telomeres could protect mice with the NOTCH1 mutation from getting CAVD.

They decided to study NOTCH1 mutant mice that had short telomeres and found that these mice had symptoms of CAVD including hardened arteries. Furthermore, mice that had the shortest telomeres had the most severe heart-related symptoms.

First author on the study Christina Theodoris, explained in a Gladstone news release how telomere length matters in animal models of age-related diseases:

“Our findings reveal a critical role for telomere length in a mouse model of age-dependent human disease. This model provides a unique opportunity to dissect the mechanisms by which telomeres affect age-dependent disease and also a system to test novel therapeutics for aortic valve disease.”

Deepak Srivastava and Christina Theodoris created mouse models of CAVD that may be used to test drug therapies for the disease. (Photo: Chris Goodfellow, Gladstone Institutes)

The team believes that there is a direct relationship between short telomeres and CAVD, likely through alterations in the activity of gene networks related to CAVD. They also propose that telomere length could influence how severe the symptoms of this disease manifest in humans.

This study is important to the field because it offers a new strategy to study age-related diseases in animal models. Senior author on the study, Dr. Deepak Srivastava, elaborated on this concept:

Deepak Srivastava, Gladstone Institutes

“Historically, we have had trouble modeling human diseases caused by mutation of just one copy of a gene in mice, which impedes research on complex conditions and limits our discovery of therapeutics. Progressive shortening of longer telomeres that are protective in mice not only reproduced the clinical disease caused by NOTCH1 mutation, it also recapitulated the spectrum of disease severity we see in humans.”

Going forward, the Gladstone team will use their new mouse model of CAVD to test drug candidates that have the potential to treat CAVD in humans. If you want to learn more about this study, watch this Gladstone video featuring an interview of Dr. Srivastava about this publication.

CIRM Alpha Clinics Network charts a new course for delivering stem cell treatments

Sometimes it feels like finding a cure is the easy part; getting it past all the hurdles it must overcome to be able to reach patients is just as big a challenge. Fortunately, a lot of rather brilliant minds are hard at work to find the most effective ways of doing just that.

Last week, at the grandly titled Second Annual Symposium of the CIRM Alpha Stem Cell Clinics Network, some of those minds gathered to talk about the issues around bringing stem cell therapies to the people who need them, the patients.

The goal of the Alpha Clinics Network is to accelerate the development and delivery of stem cell treatments to patients. In doing that one of the big issues that has to be addressed is cost; how much do you charge for a treatment that can change someone’s life, even save their life? For example, medications that can cure Hepatitis C cost more than $80,000. So how much would a treatment cost that can cure a disease like Severe Combined Immunodeficiency (SCID)? CIRM-funded researchers have come up with a cure for SCID, but this is a rare disease that affects between 40 – 100 newborns every year, so the huge cost of developing this would fall on a small number of patients.

The same approach that is curing SCID could also lead to a cure for sickle cell disease, something that affects around 100,000 people in the US, most of them African Americans. Because we are adding more people to the pool that can be treated by a therapy does that mean the cost of the treatment should go down, or will it stay the same to increase profits?

Jennifer Malin, United Healthcare

Jennifer Malin from United Healthcare did a terrific job of walking us through the questions that have to be answered when trying to decide how much to charge for a drug. She also explored the thorny issue of who should pay; patients, insurance companies, the state? As she pointed out, it’s no use having a cure if it’s priced so high that no one can afford it.

Joseph Alvarnas, the Director of Value-based Analytics at City of Hope – where the conference was held – said that in every decision we make about stem cell therapies we “must be mindful of economic reality and inequality” to ensure that these treatments are available to all, and not just the rich.

“Remember, the decisions we make now will influence not just the lives of those with us today but also the lives of all those to come.”

Of course long before you even have to face the question of who will pay for it, you must have a treatment to pay for. Getting a therapy through the regulatory process is challenging at the best of times. Add to that the fact that many researchers have little experience navigating those tricky waters and you can understand why it takes more than eight years on average for a cell therapy to go from a good idea to a clinical trial (in contrast it takes just 3.2 years for a more traditional medication to get into a clinical trial).

Sunil Kadim, QuintilesIMS

Sunil Kadam from QuintilesIMS talked about the skills and expertise needed to navigate the regulatory pathway. QuintilesIMS partners with CIRM to run the Stem Cell Center, which helps researchers apply for and then run a clinical trial, providing the guidance that is essential to keeping even the most promising research on track.

But, as always, at the heart of every conference, are the patients and patient advocates. They provided the inspiration and a powerful reminder of why we all do what we do; to help find treatments and cures for patients in need.

The Alpha Clinic Network is only a few years old but is already running 35 different clinical trials involving hundreds of patients. The goal of the conference was to discuss lessons learned and share best practices so that number of trials and patients can continue to increase.

The CIRM Board is also doing its part to pick up the pace, approving funding for up to two more Alpha Clinic sites.  The deadline to apply to be one of our new Alpha Clinics sites is May 15th, and you can learn more about how to apply on our funding page.

Since joining CIRM I have been to many conferences but this was, in my opinion, the best one I have ever intended. It brought together people from every part of the field to give the most complete vision for where we are, and where we are headed. The talks were engaging, and inspiring.

Kristin Macdonald was left legally blind by retinitis pigmentosa, a rare vision-destroying disease. A few years ago she became the first person to be treated with a CIRM-funded therapy aimed to restoring some vision. She says it is helping, that for years she lived in a world of darkness and, while she still can’t see clearly, now she can see light. She says coming out of the darkness and into the light has changed her world.

Kristin Macdonald

In the years to come the Alpha Clinics Network hopes to be able to do the same, and much more, for many more people in need.

To read more about the Alpha Clinics Meeting, check out our Twitter Moments.

Stem cell stories that caught our eye: spinal cord injury trial update, blood stem cells in lungs, and using parsley for stem cell therapies

More good news on a CIRM-funded trial for spinal cord injury. The results are now in for Asterias Biotherapeutics’ Phase 1/2a clinical trial testing a stem cell-based therapy for patients with spinal cord injury. They reported earlier this week that six out of six patients treated with 10 million AST-OPC1 cells, which are a type of brain cell called oligodendrocyte progenitor cells, showed improvements in their motor function. Previously, they had announced that five of the six patients had shown improvement with the jury still out on the sixth because that patient was treated later in the trial.

 In a news release, Dr. Edward Wirth, the Chief Medical officer at Asterias, highlighted these new and exciting results:

 “We are excited to see the sixth and final patient in the AIS-A 10 million cell cohort show upper extremity motor function improvement at 3 months and further improvement at 6 months, especially because this particular patient’s hand and arm function had actually been deteriorating prior to receiving treatment with AST-OPC1. We are very encouraged by the meaningful improvements in the use of arms and hands seen in the SciStar study to date since such gains can increase a patient’s ability to function independently following complete cervical spinal cord injuries.”

Overall, the trial suggests that AST-OPC1 treatment has the potential to improve motor function in patients with severe spinal cord injury. So far, the therapy has proven to be safe and likely effective in improving some motor function in patients although control studies will be needed to confirm that the cells are responsible for this improvement. Asterias plans to test a higher dose of 20 million cells in AIS-A patients later this year and test the 10 million cell dose in AIS-B patients that a less severe form of spinal cord injury.

 Steve Cartt, CEO of Asterias commented on their future plans:

 “These results are quite encouraging, and suggest that there are meaningful improvements in the recovery of functional ability in patients treated with the 10 million cell dose of AST-OPC1 versus spontaneous recovery rates observed in a closely matched untreated patient population. We look forward to reporting additional efficacy and safety data for this cohort, as well as for the currently-enrolling AIS-A 20 million cell and AIS-B 10 million cell cohorts, later this year.”

Lungs aren’t just for respiration. Biology textbooks may be in need of some serious rewrites based on a UCSF study published this week in Nature. The research suggests that the lungs are a major source of blood stem cells and platelet production. The long prevailing view has been that the bone marrow was primarily responsible for those functions.

The new discovery was made possible by using special microscopy that allowed the scientists to view the activity of individual cells within the blood vessels of a living mouse lung (watch the fascinating UCSF video below). The mice used in the experiments were genetically engineered so that their platelet-producing cells glowed green under the microscope. Platelets – cell fragments that clump up and stop bleeding – were known to be produced to some extent by the lungs but the UCSF team was shocked by their observations: the lungs accounted for half of all platelet production in these mice.

Follow up experiments examined the movement of blood cells between the lung and bone marrow. In one experiment, the researchers transplanted healthy lungs from the green-glowing mice into a mouse strain that lacked adequate blood stem cell production in the bone marrow. After the transplant, microscopy showed that the green fluorescent cells from the donor lung traveled to the host’s bone marrow and gave rise to platelets and several other cells of the immune system. Senior author Mark Looney talked about the novelty of these results in a university press release:

Mark Looney, MD

“To our knowledge this is the first description of blood progenitors resident in the lung, and it raises a lot of questions with clinical relevance for the millions of people who suffer from thrombocytopenia [low platelet count].”

If this newfound role of the lung is shown to exist in humans, it may provide new therapeutic approaches to restoring platelet and blood stem cell production seen in various diseases. And it will give lung transplants surgeons pause to consider what effects immune cells inside the donor lung might have on organ rejection.

Add a little vanilla to this stem cell therapy. Typically, the only connection between plants and stem cell clinical trials are the flowers that are given to the patient by friends and family. But research published this week in the Advanced Healthcare Materials journal aims to use plant husks as part of the cell therapy itself.

Though we tend to focus on the poking and prodding of stem cells when discussing the development of new therapies, an equally important consideration is the use of three-dimensional scaffolds. Stem cells tend to grow better and stay healthier when grown on these structures compared to the flat two-dimensional surface of a petri dish. Various methods of building scaffolds are under development such as 3D printing and designing molds using materials that aren’t harmful to human tissue.

Human fibroblast cells growing on decellularized parsley.
Image: Gianluca Fontana/UW-Madison

But in the current study, scientists at the University of Wisconsin-Madison took a creative approach to building scaffolds: they used the husks of parsley, vanilla and orchid plants. The researchers figured that millions of years of evolution almost always leads to form and function that is much more stable and efficient than anything humans can create. Lead author Gianluca Fontana explained in a university press release how the characteristics of plants lend themselves well to this type of bioengineering:

Gianluca Fontana, PhD

“Nature provides us with a tremendous reservoir of structures in plants. You can pick the structure you want.”

The technique relies on removing all the cells of the plant, leaving behind its outer layer which is mostly made of cellulose, long chains of sugars that make up plant cell walls. The resulting hollow, tubular husks have similar shapes to those found in human intestines, lungs and the bladder.

The researchers showed that human stem cells not only attach and grow onto the plant scaffolds but also organize themselves in alignment with the structures’ patterns. The function of human tissues rely on an organized arrangement of cells so it’s possible these plant scaffolds could be part of a tissue replacement cell product. Senior author William Murphy also points out that the scaffolds are easily altered:

William Murphy, PhD

“They are quite pliable. They can be easily cut, fashioned, rolled or stacked to form a range of different sizes and shapes.”

And the fact these scaffolds are natural products that are cheap to manufacture makes this a project well worth watching.

Don’t Be Afraid: High school stem cell researcher on inspiring girls to pursue STEM careers

As part of our CIRM scholar blog series, we’re featuring the research and career accomplishments of CIRM funded students.

Shannon Larsuel

Shannon Larsuel is a high school senior at Mayfield Senior School in Pasadena California. Last summer, she participated in Stanford’s CIRM SPARK high school internship program and did stem cell research in a lab that studies leukemia, a type of blood cancer. Shannon is passionate about helping people through research and medicine and wants to become a pediatric oncologist. She is also dedicated to inspiring young girls to pursue STEM (Science, Technology, Engineering, and Mathematics) careers through a group called the Stem Sisterhood.

I spoke with Shannon to learn more about her involvement in the Stem Sisterhood and her experience in the CIRM SPARK program. Her interview is below.


Q: What is the Stem Sisterhood and how did you get involved?

SL: The Stem Sisterhood is a blog. But for me, it’s more than a blog. It’s a collective of women and scientists that are working to inspire other young scientists who are girls to get involved in the STEM field. I think it’s a wonderful idea because girls are underrepresented in STEM fields, and I think that this needs to change.

I got involved in the Stem Sisterhood because my friend Bridget Garrity is the founder. This past summer when I was at Stanford, I saw that she was doing research at Caltech. I reconnected with her and we started talking about our summer experiences working in labs. Then she asked me if I wanted to be involved in the Stem Sisterhood and be one of the faces on her website. She took an archival photo of Albert Einstein with a group of other scientists that’s on display at Caltech and recreated it with a bunch of young women who were involved in the STEM field. So I said yes to being in the photo, and I’m also in the midst of writing a blog post about my experience at Stanford in the SPARK program.

Members of The Stem Sisterhood

Q: What does the Stem Sisterhood do?

SL: Members of the team go to elementary schools and girl scout troop events and speak about science and STEM to the young girls. The goal is to inspire them to become interested in science and to teach them about different aspects of science that maybe are not that well known.

The Stem Sisterhood is based in Los Angeles. The founder Bridget wants to expand the group, but so far, she has only done local events because she is a senior in high school. The Stem Sisterhood has an Instagram account in addition to their blog. The blog is really interesting and features interviews with women who are in science and STEM careers.

Q: How has the Stem Sisterhood impacted your life?

SL: It has inspired me to reach out to younger girls more about science. It’s something that I am passionate about, and I’d like to pursue a career in the medical field. This group has given me an outlet to share that passion with others and to hopefully change the face of the STEM world.

Q: How did you find out about the CIRM SPARK program?

SL: I knew I wanted to do a science program over the summer, but I wasn’t sure what type. I didn’t know if I wanted to do research or be in a hospital. I googled science programs for high school seniors, and I saw the one at Stanford University. It looked interesting and Stanford is obviously a great institution. Coming from LA, I was nervous that I wouldn’t be able to get in because the program had said it was mostly directed towards students living in the Bay Area. But I got in and I was thrilled. So that’s basically how I heard about it, because I googled and found it.

Q: What was your SPARK experience like?

SL: My program was incredible. I was a little bit nervous and scared going into it because I was the only high school student in my lab. As a high school junior going into senior year, I was worried about being the youngest, and I knew the least about the material that everyone in the lab was researching. But my fears were quickly put aside when I got to the lab. Everyone was kind and helpful, and they were always willing to answer my questions. Overall it was really amazing to have my first lab experience be at Stanford doing research that’s going to potentially change the world.

Shannon working in the lab at Stanford.

I was in a lab that was using stem cells to characterize a type of leukemia. The lab is hoping to study leukemia in vitro and in vivo and potentially create different treatments and cures from this research. It was so cool knowing that I was doing research that was potentially helping to save lives. I also learned how to work with stem cells which was really exciting. Stem cells are a new advancement in the science world, so being able to work with them was incredible to me. So many students will never have that opportunity, and being only 17 at the time, it was amazing that I was working with actual stem cells.

I also liked that the Stanford SPARK program allowed me to see other aspects of the medical world. We did outreach programs in the Stanford community and helped out at the blood drive where we recruited people for the bone marrow registry. I never really knew anything about the registry, but after learning about it, it really interested me. I actually signed up for it when I turned 18. We also met with patients and their families and heard their stories about how stem cell transplants changed their lives. That was so inspiring to me.

Going into the program, I was pretty sure I wanted to be a pediatric oncologist, but after the program, I knew for sure that’s what I wanted to do. I never thought about the research side of pediatric oncology, I only thought about the treatment of patients. So the SPARK program showed me what laboratory research is like, and now that’s something I want to incorporate into my career as a pediatric oncologist.

I learned so much in such a short time period. Through SPARK, I was also able to connect with so many incredible, inspired young people. The students in my program and I still have a group chat, and we text each other about college and what’s new with our lives. It’s nice knowing that there are so many great people out there who share my interests and who are going to change the world.

Stanford SPARK students.

Q: What was your favorite part of the SPARK program?

SL: Being in the lab every day was really incredible to me. It was my first research experience and I was in charge of a semi-independent project where I would do bacterial transformations on my own and run the gels. It was cool that I could do these experiments on my own. I also really loved the end of the summer poster session where all the students from the different SPARK programs came together to present their research. Being in the Stanford program, I only knew the Stanford students, but there were so many other awesome projects that the other SPARK students were doing. I really enjoyed being able to connect with those students as well and learn about their projects.

Q: Why do you want to pursue pediatric oncology?

SL: I’ve always been interested in the medical field but I’ve had a couple of experiences that really inspired me to become a doctor. My friend has a charity that raises money for Children’s Hospital Los Angeles. Every year, we deliver toys to the hospital. The first year I participated, we went to the hospital’s oncology unit and something about it stuck with me. There was one little boy who was getting his chemotherapy treatment. He was probably two years old and he really inspired to create more effective treatments for him and other children.

I also participated in the STEAM Inquiry program at my high school, where I spent two years reading tons of peer reviewed research on immunotherapy for pediatric cancer. Immunotherapy is something that really interests me. It makes sense that since cancer is usually caused by your body’s own mutations, we should be able to use the body’s immune system that normally regulates this to try and cure cancer. This program really inspired me to go into this field to learn more about how we can really tailor the immune system to fight cancer.

Q: What advice do you have for young girls interested in STEM.

SL: My advice is don’t be afraid. I think that sometimes girls are expected to be interested in less intellectual careers. This perception can strike fear into girls and make them think “I won’t be good enough. I’m not smart enough for this.” This kind of thinking is not good at all. So I would say don’t be afraid and be willing to put yourself out there. I know for me, sometimes it’s scary to try something and know you could fail. But that’s the best way to learn. Girls need to know that they are capable of doing anything and if they just try, they will be surprised with what they can do.

A stem cell clinical trial for blindness: watch Rosie’s story

Everything we do at CIRM is laser-focused on our mission: to accelerate stem cell treatments for patients with unmet medical needs. So, you might imagine what a thrill it is to meet the people who could be helped by the stem cell research we fund. People like Rosie Barrero who suffers from Retinitis Pigmentosa (RP), an inherited, incurable form of blindness, which she describes as “an impressionist painting in a foggy room”.

The CIRM team first met Rosie Barrero back in 2012 at one of our governing Board meetings. She and her husband, German, attended the meeting to advocate for a research grant application submitted by UC Irvine’s Henry Klassen. The research project aimed to bring a stem cell-based therapy for RP to clinical trials. The Board approved the project giving a glimmer of hope to Rosie and many others stricken with RP.

Now, that hope has become a reality in the form of a Food and Drug Administration (FDA)-approved clinical trial which Rosie participated in last year. Sponsored by jCyte, a company Klassen founded, the CIRM-funded trial is testing the safety and effectiveness of a non-surgical treatment for RP that involves injecting stem cells into the eye to help save or even restore the light-sensing cells in the back of the eye. The small trial has shown no negative side effects and a larger, follow-up trial, also funded by CIRM, is now recruiting patients.

Almost five years after her first visit, Rosie returned to the governing Board in February and sprinkled in some of her witty humor to describe her preliminary yet encouraging results.

“It has made a difference. I’m still afraid of public speaking but early on [before the clinical trial] it was much easier because I couldn’t see any of you. But, hello everybody! I can see you guys. I can see this room. I can see a lot of things.”

After the meeting, she sat down for an interview with the Stem Cellar team to talk about her RP story and her experience as a clinical trial participant. The three-minute video above is based on that interview. Watch it and be inspired!

Stem cells reveal developmental defects in Huntington’s disease

Three letters, C-A-G, can make the difference between being healthy and having a genetic brain disorder called Huntington’s disease (HD). HD is a progressive neurodegenerative disease that affects movement, cognition and personality. Currently more than 30,000 Americans have HD and there is no cure or treatment to stop the disease from progressing.

A genetic mutation in the huntingtin gene. caused by an expanded repeat of CAG nucleotides, the building blocks of DNA that make our genes, is responsible for causing HD. Normal people have less than 26 CAG repeats while those with 40 or more repeats will get HD. The reasons are still unknown why this trinucleotide expansion causes the disease, but scientists hypothesize that the extra CAG copies in the huntingtin gene produce a mutant version of the Huntingtin protein, one that doesn’t function the way the normal protein should.

The HD mutation causes neurodegeneration.

As with many diseases, things start to go wrong in the body long before symptoms of the disease reveal themselves. This is the case for HD, where symptoms typically manifest in patients between the ages of 30 and 50 but problems at the molecular and cellular level occur decades before. Because of this, scientists are generating new models of HD to unravel the mechanisms that cause this disease early on in development.

Induced pluripotent stem cells (iPSCs) derived from HD patients with expanded CAG repeats are an example of a cell-based model that scientists are using to understand how HD affects brain development. In a CIRM-funded study published today in the journal Nature Neuroscience, scientists from the HD iPSC Consortium used HD iPSCs to study how the HD mutation causes problems with neurodevelopment.

They analyzed neural cells made from HD patient iPSCs and looked at what genes displayed abnormal activity compared to healthy neural cells. Using a technique called RNA-seq analysis, they found that many of these “altered” genes in HD cells played important roles in the development and maturation of neurons, the nerve cells in the brain. They also observed differences in the structure of HD neurons compared to healthy neurons when grown in a lab. These findings suggest that HD patients likely have problems with neurodevelopment and adult neurogenesis, the process where the adult stem cells in your brain generate new neurons and other brain cells.

After pinpointing the gene networks that were altered in HD neurons, they identified a small molecule drug called isoxazole-9 (Isx-9) that specifically targets these networks and rescues some of the HD-related symptoms they observed in these neurons. They also tested Isx-9 in a mouse model of HD and found that the drug improved their cognition and other symptoms related to impaired neurogenesis.

The authors conclude from their findings that the HD mutation disrupts gene networks that affect neurodevelopment and neurogenesis. These networks can be targeted by Isx-9, which rescues HD symptoms and improves the mental capacity of HD mice, suggesting that future treatments for HD should focus on targeting these early stage events.

I reached out to the leading authors of this study to gain more insights into their work. Below is a short interview with Dr. Leslie Thompson from UC Irvine, Dr. Clive Svendsen from Cedars-Sinai, and Dr. Steven Finkbeiner from the Gladstone Institutes. The responses were mutually contributed.

Leslie Thompson

Steven Finkbeiner

Clive Svendsen

 

 

 

 

 

 Q: What is the mission of the HD iPSC Consortium?

To create a resource for the HD community of HD derived stem cell lines as well as tackling problems that would be difficult to do by any lab on its own.  Through the diverse expertise represented by the consortium members, we have been able to carry out deep and broad analyses of HD-associated phenotypes [observable characteristics derived from your genome].  The authorship of the paper  – the HD iPSC consortium (and of the previous consortium paper in 2012) – reflects this goal of enabling a consortium and giving recognition to the individuals who are part of it.

Q: What is the significance of the findings in your study and what novel insights does it bring to the HD field?

 Our data revealed a surprising neurodevelopmental effect of highly expanded repeats on the HD neural cells.  A third of the changes reflected changes in networks that regulate development and maturation of neurons and when compared to neurodevelopment pathways in mice, showed that maturation appeared to be impacted.  We think that the significance is that there may be very early changes in HD brain that may contribute to later vulnerability of the brain due to the HD mutation.  This is compounded by the inability to mount normal adult neurogenesis or formation of new neurons which could compensate for the effects of mutant HTT.  The genetic mutation is present from birth and with differentiated iPSCs, we are picking up signals earlier than we expected that may reflect alterations that create increased susceptibility or limited homeostatic reserves, so with the passage of time, symptoms do result.

What we find encouraging is that using a small molecule that targets the pathways that came out of the analysis, we protected against the impact of the HD mutation, even after differentiation of the cells or in an adult mouse that had had the mutation present throughout its development.

Q: There’s a lot of evidence suggesting defects in neurodevelopment and neurogenesis cause HD. How does your study add to this idea?

Agree completely that there are a number of cell, mouse and human studies that suggest that there are problems with neurodevelopment and neurogenesis in HD.  Our study adds to this by defining some of the specific networks that may be regulating these effects so that drugs can be developed around them.  Isx9, which was used to target these pathways specifically, shows that even with these early changes, one can potentially alleviate the effects. In many of the assays, the cells were already through the early neurodevelopmental stages and therefore would have the deficits present.  But they could still be rescued.

Q: Has Isx-9 been used previously in cell or animal models of HD or other neurodegenerative diseases? Could it help HD patients who already are symptomatic?

The compound has not been used that we know of in animal models to treat neurodegeneration, although was shown to affect neurogenesis and memory in mice. Isx9 was used in a study by Stuart Lipton in Parkinson’s iPSC-derived neurons in one study and it had a protective effect on apoptosis [cell death] in a study by Ryan SD et al., 2013, Cell.

We think this type of compound could help patients who are symptomatic.  Isx-9 itself is a fairly pleiotropic drug [having multiple effects] and more research would be needed [to test its safety and efficacy].

Q: Have you treated HD mice with Isx-9 during early development to see whether the molecule improves HD symptoms?

Not yet, but we would like to.

Q: What are your next steps following this study and do you have plans to translate this research into humans?

We are following up on the research in more mature HD neurons and to determine at what stages one can rescue the HD phenotypes in mice.  Also, we would need to do pharmacodynamics and other types of assays in preclinical models to assess efficacy and then could envision going into human trials with a better characterized drug.  Our goal is to ultimately translate this to human treatments in general and specifically by targeting these altered pathways.

Stem Cell Stories that Caught our Eye: stem cell insights into anorexia, Zika infection and bubble baby disease

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

Stem cell model identifies new culprit for anorexia.

Eating disorders like anorexia nervosa are often thought to be caused by psychological disturbances or societal pressure. However, research into the genes of anorexia patients suggests that what’s written in your DNA can be associated with an increased vulnerability to having this disorder. But identifying individual genes at fault for a disease this complex has remained mostly out of scientists’ reach, until now.

A CIRM-funded team from the UC San Diego (UCSD) School of Medicine reported this week that they’ve developed a stem cell-based model of anorexia and used it to identify a gene called TACR1, which they believe is associated with an increased likelihood of getting anorexia.

They took skin samples from female patients with anorexia and reprogrammed them into induced pluripotent stem cells (iPSCs). These stem cells contained the genetic information potentially responsible for causing their anorexia. The team matured these iPSCs into brain cells, called neurons, in a dish, and then studied what genes got activated. When they looked at the genes activated by anorexia neurons, they found that TACR1, a gene associated with psychiatric disorders, was switched on higher in anorexia neurons than in healthy neurons. These findings suggest that the TACR1 gene could be an identifier for this disease and a potential target for developing new treatments.

In a UCSD press release, Professor and author on the study, Alysson Muotri, said that they will follow up on their findings by studying stem cell lines derived from a larger group of patients.

Alysson Muotri UC San Diego

“But more to the point, this work helps make that possible. It’s a novel technological advance in the field of eating disorders, which impacts millions of people. These findings transform our ability to study how genetic variations alter brain molecular pathways and cellular networks to change risk of anorexia nervosa — and perhaps our ability to create new therapies.”

Anorexia is a disease that affects 1% of the global population and although therapy can be an effective treatment for some, many do not make a full recovery. Stem cell-based models could prove to be a new method for unlocking new clues into what causes anorexia and what can cure it.

Nature versus Zika, who will win?

Zika virus is no longer dominating the news headlines these days compared to 2015 when large outbreaks of the virus in the Southern hemisphere came to a head. However, the threat of Zika-induced birth defects, like microcephaly to pregnant women and their unborn children is no less real or serious two years later. There are still no effective vaccines or antiviral drugs that prevent Zika infection but scientists are working fast to meet this unmet need.

Speaking of which, scientists at UCLA think they might have a new weapon in the war against Zika. Back in 2013, they reported that a natural compound in the body called 25HC was effective at attacking viruses and prevented human cells from being infected by viruses like HIV, Ebola and Hepatitis C.

When the Zika outbreak hit, they thought that this compound could potentially be effective at preventing Zika infection as well. In their new study published in the journal Immunity, they tested a synthetic version of 25HC in animal and primate models, they found that it protected against infection. They also tested the compound on human brain organoids, or mini brains in a dish made from pluripotent stem cells. Brain organoids are typically susceptible to Zika infection, which causes substantial cell damage, but this was prevented by treatment with 25HC.

Left to right: (1) Zika virus (green) infects and destroys the formation of neurons (pink) in human stem cell-derived brain organoids.  (2) 25HC blocks Zika infection and preserves neuron formation in the organoids. (3) Reduced brain size and structure in a Zika-infected mouse brain. (4) 25HC preserves mouse brain size and structure. Image courtesy of UCLA Stem Cell.

A UCLA news release summarized the impact that this research could have on the prevention of Zika infection,

“The new research highlights the potential use of 25HC to combat Zika virus infection and prevent its devastating outcomes, such as microcephaly. The research team will further study whether 25HC can be modified to be even more effective against Zika and other mosquito-borne viruses.”

Harnessing a naturally made weapon already found in the human body to fight Zika could be an alternative strategy to preventing Zika infection.

Gene therapy in stem cells gives hope to bubble-babies.

Last week, an inspiring and touching story was reported by Erin Allday in the San Francisco Chronicle. She featured Ja’Ceon Golden, a young baby not even 6 months old, who was born into a life of isolation because he lacked a properly functioning immune system. Ja’Ceon had a rare disease called severe combined immunodeficiency (SCID), also known as bubble-baby disease.

 

Ja’Ceon Golden is treated by patient care assistant Grace Deng (center) and pediatric oncology nurse Kat Wienskowski. Photo: Santiago Mejia, The Chronicle.

Babies with SCID lack the body’s immune defenses against infectious diseases and are forced to live in a sterile environment. Without early treatment, SCID babies often die within one year due to recurring infections. Bone marrow transplantation is the most common treatment for SCID, but it’s only effective if the patient has a donor that is a perfect genetic match, which is only possible for about one out of five babies with this disease.

Advances in gene therapy are giving SCID babies like Ja’Ceon hope for safer, more effective cures. The SF Chronicle piece highlights two CIRM-funded clinical trials for SCID run by UCLA in collaboration with UCSF and St. Jude Children’s Research Hospital. In these trials, scientists isolate the bone marrow stem cells from SCID babies, correct the genetic mutation causing SCID in their stem cells, and then transplant them back into the patient to give them a healthy new immune system.

The initial results from these clinical trials are promising and support other findings that gene therapy could be an effective treatment for certain genetic diseases. CIRM’s Senior Science Officer, Sohel Talib, was quoted in the Chronicle piece saying,

“Gene therapy has been shown to work, the efficacy has been shown. And it’s safe. The confidence has come. Now we have to follow it up.”

Ja’Ceon was the first baby treated at the UCSF Benioff Children’s Hospital and so far, he is responding well to the treatment. His great aunt Dannie Hawkins said that it was initially hard for her to enroll Ja’Ceon in this trial because she was a partial genetic match and had the option of donating her own bone-marrow to help save his life. In the end, she decided that his involvement in the trial would “open the door for other kids” to receive this treatment if it worked.

Ja’Ceon Golden plays with patient care assistant Grace Deng in a sterile play area at UCSF Benioff Children’s Hospital.Photo: Santiago Mejia, The Chronicle

It’s brave patients and family members like Ja’Ceon and Dannie that make it possible for research to advance from clinical trials into effective treatments for future patients. We at CIRM are eternally grateful for their strength and the sacrifices they make to participate in these trials.

Three people left blind by Florida clinic’s unproven stem cell therapy

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Unproven stem cell treatments endanger patients: Photo courtesy Healthline

The report makes for chilling reading. Three women, all suffering from macular degeneration – the leading cause of vision loss in the US – went to a Florida clinic hoping that a stem cell therapy would save their eyesight. Instead, it caused all three to go blind.

The study, in the latest issue of the New England Journal of Medicine, is a warning to all patients about the dangers of getting unproven, unapproved stem cell therapies.

In this case, the clinic took fat and blood from the patient, put the samples through a centrifuge to concentrate the stem cells, mixed them together and then injected them into the back of the woman’s eyes. In each case they injected this mixture into both eyes.

Irreparable harm

Within days the women, who ranged in age from 72 to 88, began to experience severe side effects including bleeding in the eye, detached retinas, and vision loss. The women got expert treatment at specialist eye centers to try and undo the damage done by the clinic, but it was too late. They are now blind with little hope for regaining their eyesight.

In a news release Thomas Alibini, one of the lead authors of the study, says clinics like this prey on vulnerable people:

“There’s a lot of hope for stem cells, and these types of clinics appeal to patients desperate for care who hope that stem cells are going to be the answer, but in this case these women participated in a clinical enterprise that was off-the-charts dangerous.”

Warning signs

So what went wrong? The researchers say this clinic’s approach raised a number of “red flags”:

  • First there is almost no evidence that the fat/blood stem cell combination the clinic used could help repair the photoreceptor cells in the eye that are attacked in macular degeneration.
  • The clinic charged the women $5,000 for the procedure. Usually in FDA-approved trials the clinical trial sponsor will cover the cost of the therapy being tested.
  • Both eyes were injected at the same time. Most clinical trials would only treat one eye at a time and allow up to 30 days between patients to ensure the approach was safe.
  • Even though the treatment was listed on the clinicaltrials.gov website there is no evidence that this was part of a clinical trial, and certainly not one approved by the Food and Drug Administration (FDA) which regulates stem cell therapies.

As CIRM’s Abla Creasey told the San Francisco Chronicle’s Erin Allday, there is little evidence these fat stem cells are effective, or even safe, for eye conditions.

“There’s no doubt there are some stem cells in fat. As to whether they are the right cells to be put into the eye, that’s a different question. The misuse of stem cells in the wrong locations, using the wrong stem cells, is going to lead to bad outcomes.”

The study points out that not all projects listed on the Clinicaltrials.gov site are checked to make sure they are scientifically sound and have done the preclinical testing needed to reduce the likelihood they may endanger patients.

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Jeffrey Goldberg

Jeffrey Goldberg, a professor of Ophthalmology at Stanford and the co-author of the study, says this is a warning to all patients considering unproven stem cell therapies:

“There is a lot of very well-founded evidence for the positive potential of stem therapy for many human diseases, but there’s no excuse for not designing a trial properly and basing it on preclinical research.”

There are a number of resources available to people considering being part of a clinical trial including CIRM’s “So You Want to Participate in a Clinical Trial”  and the  website A Closer Look at Stem Cells , which is sponsored by the International Society for Stem Cell Research (ISSCR).

CIRM is currently funding two clinical trials aimed at helping people with vision loss. One is Dr. Mark Humayun’s research on macular degeneration – the same disease these women had – and the other is Dr. Henry Klassen’s research into retinitis pigmentosa. Both these projects have been approved by the FDA showing they have done all the testing required to try and ensure they are safe in people.

In the past this blog has been a vocal critic of the FDA and the lengthy and cumbersome approval process for stem cell clinical trials. We have, and still do, advocate for a more efficient process. But this study is a powerful reminder that we need safeguards to protect patients, that any therapy being tested in people needs to have undergone rigorous testing to reduce the likelihood it may endanger them.

These three women paid $5,000 for their treatment. But the final cost was far greater. We never want to see that happen to anyone ever again.

Building the World’s Largest iPSC Repository: An Interview with CIRM’s Stephen Lin

This blog originally appeared on RegMedNet and was provided by Freya Leask, Editor & Community Manager of RegMedNet. In this interview, Stephen Lin, Senior Science Officer at the California Institute Regenerative Medicine (CIRM), discusses the scope, challenges and potential of CIRM’s iPSC Initiative. 

 

Stephen Lin

Stephen Lin received his PhD from Washington University (MO, USA) and completed his postdoctoral work at Harvard University (MA, USA). Lin is a senior science officer at CIRM which he joined in 2015 to oversee the development of a $32 million repository of iPSCs generated from up to 3000 healthy and diseased individuals and covering both complex and rare diseases. He also oversees a $40 million initiative to apply genomics and bioinformatics approaches to stem cell research and development of therapies. Lin is the program lead on the CIRM Translating Center which focuses on supporting the process development, safety/toxicity studies and manufacturing of stem cell therapy candidates to prepare them for clinical trials. He was previously a scientist at StemCells, Inc (CA, USA) and a staff scientist team lead at Thermo Fisher Scientific (MA, USA).

Q: Please introduce yourself and your institution.

I completed my PhD at Washington University in biochemistry, studying the mechanisms of aging, before doing my postdoc at Harvard, investigating programmed cell death. After that, I went into industry and have been working with stem cells ever since.

I was at the biotech company StemCells, Inc for 6 years where I worked on cell therapeutics. I then joined what was Life Technologies which is now Thermo Fisher Scientific.  I joined CIRM in 2015 as they were launching two new initiatives, the iPSC repository and the genomics initiative, which were a natural combination of my experience in both the stem cells industry and in genetic analysis.  I’ve been here for a year and a half, overseeing both initiatives as well as the CIRM Translating Center.

Q: What prompted the development of the iPSC repository?

Making iPSCs is challenging! It isn’t trivial for many research labs to produce these materials, especially for a wide variety of diseases; hence, the iPSC repository was set up in 2013. In its promotion of stem cells, CIRM had the financial resources to develop a bank for researchers and build up a critical mass of lines to save researchers the trouble of recruiting the patients, getting the consents, making and quality controlling the cells. CIRM wanted to cut that out and bring the resources straight to the research community.

Q: What are the challenges of storage so many iPSCs?

Many of the challenges of storing iPSCs and ensuring their quality are overcome with adequate quality controls at the production step. The main challenge is that we’re collecting samples from up to 3000 donors – the logistics of processing that many tissue samples from 11 funded and nonfunded collectors are difficult. The lines are being produced in the same uniform manner by one agency, Cellular Dynamics International (WI, USA), to ensure quality in terms of pluripotency, karyotyping and sterility testing.

Once the lines are made, they are stored at the Coriell Institute (NJ, USA). During storage, there is a challenge in simply keeping track of and distributing that many samples; we will have approximately 40 vials for each of the 3000 main lines. Both Cellular Dynamics and Coriell have sophisticated tracking systems and Coriell have set up a public catalog website where anyone can go to read about and order the lines. Most collections don’t have this functionality, as the IT infrastructure required for searching and displaying the lines along with clinical information, the ordering process, material transfer agreements and, for commercial uses, the licensing agreements was very complex.

Q: Can anyone use the repository?

Yes, they can! There is a fee to utilize the lines but we encourage researchers anywhere in the world to order them. The lines are mostly for research and academic purposes but the collection was built to be commercialized, all the way from collecting the samples. When the samples were collected, the patient consent included, among other things, banking, distribution, genetic characterization and commercialization.

The lines also have pre-negotiated licensing agreements with iPS Academia Japan (Kyoto, Japan) and the Wisconsin Alumni Research Foundation (WI, USA). Commercial entities that want to use the cells for drug screening can obtain a license which allows them to use these lines for drug discovery and drug screening purposes without fear of back payment royalties down the road. People often forget during drug screening that the intellectual property to make the iPSCs is still under patent, so if you do discover a drug using iPSCs without taking care of these licensing agreements, your discovery could be liable to ownership by that original intellectual property holder.

Q: Will wider access to high quality iPSCs accelerate discovery?

That’s our hope. When people make iPSCs, the quality can be highly variable depending on the lab’s background and experience, which was another impetus to create the repository. Cellular Dynamics have set up a very robust system to create these lines in a rigorous quality control pipeline to guarantee that these lines are pluripotent and genetically stable.

Q: What diseases could these lines be used to study and treat?

We collected samples from patients with many different diseases – from neurodevelopmental disorders including epilepsy and neurodegenerative diseases such as Alzheimer’s, to eye disease and diabetes – as well as the corresponding controls. We also have lines from rare diseases, where the communities have no other tools to study them, for example, ADCY5 related dyskinesia. You can read our recent blogs about our efforts to generate new iPSC lines for ADCY5 and other rare diseases here and here.

Q: What are your plans for the iPSC initiative this year?

We’re currently the largest publicly available repository in the world and we aren’t complete yet. We have just under half of the lines in with the other half still being produced and quality controlled. Something else we want to do is add further information to make the lines more valuable and ensure the drug models are constantly improving. The reason people will want to use iPSCs for human disease modeling is whether they have valuable information associated with them.  For example, we are trying to add genetic and sequencing information to the catalog for lines that have it. This will also allow researchers to prescreen the lines they are interested in to match the diseases and drugs they are studying.

Q: Does the future for iPSCs lie in being utilized as tools to find therapeutics as opposed to therapeutics themselves?

I think the future is two pronged. There is certainly a future for disease modeling and drug screening. There is currently an initiative within the FDA, the CiPA initiative, is designed to replace current paradigms for drug safety testing with computational model and stem cell models. In particular, they hope to be able to screen drugs for cardiotoxicity in stem cells before they go to patients.  Mouse and rodent models have different receptors and ion channels so these cardiotoxic effects aren’t usually seen until clinical trials.

The other avenue is in therapeutics. However, this will come later in the game because the lines being used for research often can’t be used for therapeutics. Patient consent for therapeutic use has to be obtained at sample collection, the tissue should be handled in compliance with good lab practice and the lines must be produced following good manufacturing process (GMP) guidelines. They must then be characterized to ensure they have met all safety protocols for iPSC therapeutics.

There is already a second trial being initiated in Japan of an iPSC therapeutic to treat macular degeneration, utilizing allogenic lines that are human leukocyte antigen-compatible and extensively safety profiled. Companies such as Lonza (Basel, Switzerland) and Cellular Dynamics are starting to produce their own GMP lines, and CIRM is funding some translation programs where clinical grade iPSCs are being produced for therapeutics.


Further Reading

3D printing blood vessels: a key step to solving the organ donor crisis

About 120,000 people in the U.S. are on a waiting list for an organ donation and every day 22 of those people will die because there aren’t enough available organs. To overcome this organ donor crisis, bioengineers are working hard to develop 3D printing technologies that can construct tissues and organs from scratch by using cells as “bio-ink”.

Though each organ type presents its own unique set of 3D bioprinting challenges, one key hurdle they all share is ensuring that the transplanted organ is properly linked to a patient’s  circulatory system, also called the vasculature. Like the intricate system of pipes required to distribute a city’s water supply to individual homes, the blood vessels of our circulatory system must branch out and reach our organs to provide oxygen and nutrients via the blood. An organ won’t last long after transplantation if it doesn’t establish this connection with the vasculature.

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Digital model of blood vessel network. Photo: Erik Jepsen/UC San Diego Publications

In a recent UC San Diego (UCSD) study, funded in part by CIRM, a team of engineers report on an important first step toward overcoming this challenge: they devised a new 3D bioprinting method to recreate the complex architecture of blood vessels found near organs. This type of 3D bioprinting approach has been attempted by other labs but these earlier methods only produced simple blood vessel shapes that were costly and took hours to fabricate.  The UCSD team’s home grown 3D bioprinting process, in comparison, uses inexpensive components and only takes seconds to complete. Wei Zhu, the lead author on the Biomaterials publication, expanded on this comparison in a press release:

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Wei Zhu

“We can directly print detailed microvasculature structures in extremely high resolution. Other 3D printing technologies produce the equivalent of ‘pixelated’ structures in comparison and usually require … additional steps to create the vessels.”

 

As a proof of principle, the bioprinted vessel structures – made with two human cell types found in blood vessels – were transplanted under the skin of mice. After two weeks, analysis of the skin showed that the human grafts were thriving and had integrated with the mice’s blood vessels. In fact, the presence of red blood cells throughout these fused vessels provided strong evidence that blood was able to circulate through them. Despite these promising results a lot of work remains.

3d-printing-blood-vessels-3

Microscopic 3D printed blood vessel structure. Photo: Erik Jepsen/UC San Diego Publications

As this technique comes closer to a reality, the team envisions using induced pluripotent stem cells to grow patient-specific organs and vasculature which would be less likely to be rejected by the immune system.

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Shaochen Chen

“Almost all tissues and organs need blood vessels to survive and work properly. This is a big bottleneck in making organ transplants, which are in high demand but in short supply,” says team lead Shaochen Chen. “3D bioprinting organs can help bridge this gap, and our lab has taken a big step toward that goal.”

 

We eagerly await the day when those transplant waitlists become a thing of the past.