Stem Cell Roundup: watching brain cells in real time, building better heart cells, and the plot thickens on the adult neurogenesis debate

Here are the stem cell stories that caught our eye this week.

Watching brain cells in real time

This illustration depicts a new method that enables scientists to see an astrocyte (green) physically interacting with a neuronal synapse (red) in real time, and producing an optical signal (yellow). (Khakh Lab, UCLA Health)

Our stem cell photo of the week is brought to you by the Khakh lab at UCLA Health. The lab developed a new method that allows scientists to watch brain cells interact in real time. Using a technique called fluorescence resonance energy-transfer (FRET) microscopy, the team can visualize how astrocytes (key support cells in our central nervous system) and brain cells called neurons form connections in the mouse brain and how these connections are affected by diseases like Alzheimer’s and ALS.

Baljit Khakh, the study’s first author, explained the importance of their findings in a news release:

“This new tool makes possible experiments that we have been wanting to perform for many years. For example, we can now observe how brain damage alters the way that astrocytes interact with neurons and develop strategies to address these changes.”

The study was published this week in the journal Neuron.


Turn up the power: How to build a better heart cell (Todd Dubnicoff)

For years now, researchers have had the know-how to reprogram a donor’s skin cells into induced pluripotent stem cells (iPSCs) and then specialize them into heart muscle cells called cardiomyocytes. The intervening years have focused on optimizing this method to accurately model the biology of the adult human heart as a means to test drug toxicity and ultimately develop therapies for heart disease. Reporting this week in Nature, scientists at Columbia University report an important step toward those goals.

The muscle contractions of a beating heart occur through natural electrical impulses generated by pacemaker cells. In the case of lab-grown cardiomyocytes, introducing mechanical and electrical stimulation is required to reliably generate these cells. In the current study, the research team showed that the timing and amount of stimulation is a critical aspect to the procedure.

The iPS-derived cardiomyocytes have formed heart tissue that closely mimics human heart functionality at over four weeks of maturation. Credit: Gordana Vunjak-Novakovic/Columbia University.

The team tested three scenarios on iPSC-derived cardiomyocytes (iPSC-CMs): no electrical stimulation for 3 weeks, constant stimulation for 3 weeks, and finally, two weeks of increasingly higher stimulation followed by a week of constant stimulation. This third setup mimics the changes that occur in a baby’s heart just before and just after birth.

These scenarios were tested in 12 day-old and 28 day-old iPSC-CMs. The results show that only the 12 day-old cells subjected to the increasing amounts of stimulation gave rise to fully mature heart muscle cells. On top of that, it only took four weeks to make those cells. Seila Selimovic, Ph.D., an expert at the National Institutes of Health who was not involved in the study, explained the importance of these findings in a press release:

“The resulting engineered tissue is truly unprecedented in its similarity to functioning human tissue. The ability to develop mature cardiac tissue in such a short time is an important step in moving us closer to having reliable human tissue models for drug testing.”

Read more at: https://phys.org/news/2018-04-early-bioengineered-human-heart-cells.html#jCp


Yes we do, no we don’t. More confusion over growing new brain cells as we grow older (Kevin McCormack)

First we didn’t, then we did, then we didn’t again, now we do again. Or maybe we do again.

The debate over whether we are able to continue making new neurons as we get older took another twist this week. Scientists at Columbia University said their research shows we do make new neurons in our brain, even as we age.

This image shows what scientists say is a new neuron in the brain of an older human. A new study suggests that humans continue to make new neurons throughout their lives. (Columbia University Irving Medical Center)

In the study, published in the journal Cell Stem Cell, the researchers examined the brains of 28 deceased donors aged 14 to 79. They found similar numbers of precursor and immature neurons in all the brains, suggesting we continue to develop new brain cells as we age.

This contrasts with a UCSF study published just last month which came to the opposite conclusion, that there was no evidence we make new brain cells as we age.

In an interview in the LA Times, Dr. Maura Boldrini, the lead author on the new study, says they looked at a whole section of the brain rather than the thin tissues slices the UCSF team used:

“In science, the absence of evidence is not evidence of absence. If you can’t find something it doesn’t mean that it is not there 100%.”

Well, that resolves that debate. At least until the next study.

Stem Cell Round: Improving memory, building up “good” fat, nanomedicine

Stem Cell Photo of the Week

roundup03618In honor of brain awareness week, our featured stem cell photo is of the brain! Scientists at the Massachusetts General Hospital and Harvard Stem Cell Institute identified a genetic switch that could potentially improve memory during aging and symptoms of PTSD. Shown in this picture are dentate gyrus cells (DGC) (green) and CA3 interneurons (red) located in the memory-forming area of the brain known as the hippocampus. By reducing the levels of a protein called abLIM3 in the DGCs of older mice, the researchers were able to boost the connections between DGCs and CA3 cells, which resulted in an improvement in the memories of the mice. The team believes that targeting this protein in aging adults could be a potential strategy for improving memory and treating patients with post-traumatic stress disorder (PTSD). You can read more about this study in The Harvard Gazette.

New target for obesity.
Fat cells typically get a bad rap, but there’s actually a type of fat cell that is considered “healthier” than others. Unlike white fat cells that store calories in the form of energy, brown fat cells are packed with mitochondria that burn energy and produce heat. Babies have brown fat, so they can regulate their body temperature to stay warm. Adults also have some brown fat, but as we get older, our stores are slowly depleted.

In the fight against obesity, scientists are looking for ways to increase the amount of brown fat and decrease the amount of white fat in the body. This week, CIRM-funded researchers from the Salk Institute identified a molecule called ERRg that gives brown fat its ability to burn energy. Their findings, published in Cell Reports, offer a new target for obesity and obesity-related diseases like diabetes and fatty liver disease.

The team discovered that brown fat cells produce the ERRg molecule while white fat cells do not. Additionally, mice that couldn’t make the ERRg weren’t able to regulate their body temperature in cold environments. The team concluded in a news release that ERRg is “involved in protection against the cold and underpins brown fat identity.” In future studies, the researchers plan to activate ERRg in white fat cells to see if this will shift their identity to be more similar to brown fat cells.

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Mice that lack ERR aren’t able to regulate their body temperature and are much colder (right) than normal mice (left). (Image credit Salk Institute)

Tale of two nanomedicine stories: making gene therapies more efficient with a bit of caution (Todd Dubnicoff).
This week, the worlds of gene therapy, stem cells and nanomedicine converged for not one, but two published reports in the journal American Chemistry Society NANO.

The first paper described the development of so-called nanospears – tiny splinter-like magnetized structures with a diameter 5000 times smaller than a strand of human hair – that could make gene therapy more efficient and less costly. Gene therapy is an exciting treatment strategy because it tackles genetic diseases at their source by repairing or replacing faulty DNA sequences in cells. In fact, several CIRM-funded clinical trials apply this method in stem cells to treat immune disorders, like severe combined immunodeficiency and sickle cell anemia.

This technique requires getting DNA into diseased cells to make the genetic fix. Current methods have low efficiency and can be very damaging to the cells. The UCLA research team behind the study tested the nanospear-delivery of DNA encoding a gene that causes cells to glow green. They showed that 80 percent of treated cells did indeed glow green, a much higher efficiency than standard methods. And probably due to their miniscule size, the nanospears were gentle with 90 percent of the green glowing cells surviving the procedure.

As Steve Jonas, one of the team leads on the project mentions in a press release, this new method could bode well for future recipients of gene therapies:

“The biggest barrier right now to getting either a gene therapy or an immunotherapy to patients is the processing time. New methods to generate these therapies more quickly, effectively and safely are going to accelerate innovation in this research area and bring these therapies to patients sooner, and that’s the goal we all have.”

While the study above describes an innovative nanomedicine technology, the next paper inserts a note of caution about how experiments in this field should be set up and analyzed. A collaborative team from Brigham and Women’s Hospital, Stanford University, UC Berkeley and McGill University wanted to get to the bottom of why the many advances in nanomedicine had not ultimately led to many new clinical trials. They set out looking for elements within experiments that could affect the uptake of nanoparticles into cells, something that would muck up the interpretation of results.

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imaging of female human amniotic stem cells incubated with nanoparticles demonstrated a significant increase in uptake compared to male cells. (Green dots: nanoparticles; red: cell staining; blue: nuclei) Credit: Morteza Mahmoudi, Brigham and Women’s Hospital.

In this study, they report that the sex of cells has a surprising, noticeable impact on nanoparticle uptake. Nanoparticles were incubated with human amniotic stem cells derived from either males or females. The team showed that the female cells took up the nanoparticles much more readily than the male cells.  Morteza Mahmoudi, PhD, one of the authors on the paper, explained the implications of these results in a press release:

“These differences could have a critical impact on the administration of nanoparticles. If nanoparticles are carrying a drug to deliver [including gene therapies], different uptake could mean different therapeutic efficacy and other important differences, such as safety, in clinical data.”

 

Lessons Learned & Knowledge Shared: 3rd Annual Alpha Clinics Symposium Celebrates the Delivery of Stem Cell Treatments to Patients

The CIRM Alpha Stem Cell Clinics (ASCC) Network was launched in 2015 to address a compelling unmet medical need for rigorous, FDA regulated, stem cell-related clinical trials for patients with challenging, incurable diseases. Since its inception, the Network has treated more than 200 patients in over 40 clinical trials at six leading California medical centers: UC San Diego, City of Hope, UCLA and UC Irvine, UCSF and UC Davis. That has enabled the Network to accumulate a wealth of experience and insight into how best to deliver treatments to patients, and each year it celebrates and showcases this knowledge at the CIRM Alpha Clinics Annual Symposium.

The Network is celebrating the 3rd anniversary of the ASCC Symposium on April 19th on the campus of the University of California at Los Angeles. This year’s theme is the Delivery of Stem Cell Therapeutics to Patients. Clinical investigators, scientists, patients, patient advocates, and the public will engage in thoughtful discussions on how novel stem cell treatments are now a reality. The symposium will address advancements and accomplishments of the ASCC Network in addition to developments and applications in the field of stem cell-based therapeutics. Treatments for cancer, HIV/AIDS, spinal cord injury and stroke will be featured. In addition, this year’s featured keynote speaker is David Mitchell President and Founder of Patients for Affordable Drugs.

The symposium is open to the public and is free. You can find the full agenda for the symposium here and registration can be found on the UCLA ASCC Eventbrite page. The event is highly interactive allowing participants opportunities to ask questions, network and learn about the latest developments in stem cell treatments.

Researcher and patient advocate panel at a past CIRM Alpha Clinic symposium: L to R: David Higgins, CIRM Board; David Parry, GSK; Catriona Jamieson, UCSD: John Zaia, City of Hope; John Adams, UCLA

Patient advocates speak up at the City of Hope 2nd Annual ASCC Network Symposium. (Image courtesy of the City of Hope)


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Stem Cell Roundup: Improving muscle function in muscular dystrophy; Building a better brain; Boosting efficiency in making iPSC’s

Here are the stem cell stories that caught our eye this week.

Photos of the week

TGIF! We’re so excited that the weekend is here that we are sharing not one but TWO amazing stem cell photos of the week.

RMI IntestinalChip

Image caption: Cells of a human intestinal lining, after being placed in an Intestine-Chip, form intestinal folds as they do in the human body. (Photo credit: Cedars-Sinai Board of Governors Regenerative Medicine Institute)

Photo #1 is borrowed from a blog we wrote earlier this week about a new stem cell-based path to personalized medicine. Scientists at Cedars-Sinai are collaborating with a company called Emulate to create intestines-on-a-chip using human stem cells. Their goal is to create 3D-organoids that represent the human gut, grow them on chips, and use these gut-chips to screen for precision medicines that could help patients with intestinal diseases. You can read more about this gut-tastic research here.

Young mouse heart 800x533

Image caption: UCLA scientists used four different fluorescent-colored proteins to determine the origin of cardiomyocytes in mice. (Image credit: UCLA Broad Stem Cell Research Center/Nature Communications)

Photo #2 is another beautiful fluorescent image, this time of a cross-section of a mouse heart. CIRM-funded scientists from UCLA Broad Stem Cell Research Center are tracking the fate of stem cells in the developing mouse heart in hopes of finding new insights that could lead to stem cell-based therapies for heart attack victims. Their research was published this week in the journal Nature Communications and you can read more about it in a UCLA news release.

Stem cell injection improves muscle function in muscular dystrophy mice

Another study by CIRM-funded Cedars-Sinai scientists came out this week in Stem Cell Reports. They discovered that they could improve muscle function in mice with muscular dystrophy by injecting cardiac progenitor cells into their hearts. The injected cells not only improved heart function in these mice, but also improved muscle function throughout their bodies. The effects were due to the release of microscopic vesicles called exosomes by the injected cells. These cells are currently being used in a CIRM-funded clinical trial by Capricor therapeutics for patients with Duchenne muscular dystrophy.

How to build a better brain (blob)

For years stem cell researchers have been looking for ways to create “mini brains”, to better understand how our own brains work and develop new ways to repair damage. So far, the best they have done is to create blobs, clusters of cells that resemble some parts of the brain. But now researchers at the Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research at UCLA have come up with a new method they think can advance the field.

Their approach is explained in a fascinating article in the journal Science News, where lead researcher Bennet Novitch says finding the right method is like being a chef:

“It’s like making a cake: You have many different ways in which you can do it. There are all sorts of little tricks that people have come up with to overcome some of the common challenges.”

Brain cake. Yum.

A more efficient way to make iPS cells

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Shinya Yamanaka. (Image source: Ko Sasaki, New York Times)

In 2006 Shinya Yamanaka discovered a way to take ordinary adult cells and reprogram them into embryonic-like stem cells that have the ability to turn into any other cell in the body. He called these cells induced pluripotent stem cells or iPSC’s. Since then researchers have been using these iPSC’s to try and develop new treatments for deadly diseases.

There’s been a big problem, however. Making these cells is really tricky and current methods are really inefficient. Out of a batch of, say, 1,000 cells sometimes only one or two are turned into iPSCs. Obviously, this slows down the pace of research.

Now researchers in Colorado have found a way they say dramatically improves on that. The team says it has to do with controlling the precise levels of reprogramming factors and microRNA and…. Well, you can read how they did it in a news release on Eurekalert.

 

 

 

Just a Mom: The Journey of a Sickle Cell Disease Patient Advocate [video]

Adrienne Shapiro will tell you that she’s just a mom.

And it’s true. She is just a mom. Just a mom who is the fourth generation of mothers in her family to have children born with sickle cell disease. Just a mom who was an early advocate of innovative stem cell and gene therapy research by UCLA scientist Dr. Don Kohn which has led to an on-going, CIRM-funded clinical trial for sickle cell disease. Just a mom who is the patient advocate representative on a Clinical Advisory Panel (CAP) that CIRM is creating to help guide this clinical trial.

She’s just a mom who has become a vocal stem cell activist, speaking to various groups about the importance of CIRM’s investments in both early stage research and clinical trials. She’s just a mom who was awarded a Stem Cell and Regenerative Medicine Action Award at last month’s World Stem Cell Summit. She’s just a mom who, in her own words, “sees a new world not just for her children but for so many other children”, through the promise of stem cell therapies.

Yep, she’s just a mom. And it’s the tireless advocacy of moms like Adrienne that will play a critical role in accelerating stem cell therapies to patients with unmet medical needs. We can use all the moms we can get.

Adrienne Shapiro speaks to the CIRM governing Board about her journey as a patient advocate

Alpha clinics and a new framework for accelerating stem cell treatments

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Last week, at the World Stem Cell Summit in Miami, CIRM took part in a panel discussion about the role and importance of Alpha Clinics in not just delivering stem cell therapies, but in helping create a new, more collaborative approach to medicine. The Alpha Clinic concept is to create  a network of top medical centers that specialize in delivering stem cell clinical trials to patients.

The panel was moderated by Dr. Tony Atala, Director of the Wake Forest Institute for Regenerative Medicine. He said the term Alpha Clinic came from CIRM and the Alpha Stem Cell Clinic Network that we helped create. That network now has five specialist health care centers that deliver stem cell therapies to patients: UC San Diego, UCLA/UC Irvine, City of Hope, UC Davis, and  UCSF/Children’s Hospital Oakland.

This is a snapshot of that conversation.

Alpha Clinics Advancing Stem Cell Trials

Dr. Maria Millan, CIRM’s President & CEO:

“The idea behind the Alpha Stem Cell Clinic Network is that CIRM is in the business of accelerating treatments to patients with unmet medical needs. We fund research from the earliest discovery stage to clinical trials. What was anticipated is that, if the goal is to get these discoveries into the clinics then we’ll need a specific set of expertise and talents to deliver those treatments safely and effectively, to gather data from those trials and move the field forward. So, we set out to create a learning network, a sharing network and a network that is more than the sum of its parts.”

Dr. Joshua Hare,  Interdisciplinary Stem Cell Institute, University of Miami, said that idea of collaboration is critical to advancing the field:

 

“What we learned is that having the Alpha Stem Cell Clinic concept helps investigators in other areas learn from what earlier researchers have done, helping accelerate their work.

For example, we have had a lot of experience in working with rare diseases and we can use the experience we have in treating one disease area in working in others. This shared experience can help us develop deeper understanding in terms of delivering therapies and dosing.”

Susan Solomon, CEO New York Stem Cell Foundation Research Institute. NYSCF has several clinical trials underway. She says in the beginning it was hard finding reputable clinics that could deliver these potentially ground breaking but still experimental therapies:

 

“My motivation was born out of my own frustration at the poor choices we had in dealing with some devastating diseases, so in order to move things ahead we had to have an alpha clinic that is not just doing clinical trials but is working to overcome obstacles in the field.”

Greg Simon represented the, Biden Cancer Initiative, whose  mission is to develop and drive implementation of solutions to accelerate progress in cancer prevention, detection, diagnosis, research, and care, and to reduce disparities in cancer outcomes. He says part of the problem is that people think there are systems already in place that promote collaboration and cooperation, but that’s not really the case.  

 

“In the Cancer Moonshot and the Biden Cancer Initiative we are trying to create the cancer research initiative that people think we already have. People think doctors share knowledge. They don’t. People think they can just sign up for clinical trials. They can’t. People think there are standards for describing a cancer. There aren’t. So, all the things you think you know about the science behind cancer are wrong. We don’t have the system people think is in place. But we want to create that.

If we are going to have a unified system we need common standards through cancer research, shared knowledge, and clinical trial reforms. All my professional career it was considered unethical to refer to a clinical trial as a treatment, it was research. That’s no longer the case. Many people are now told this is your last best hope for treatment and it’s changed the way people think about clinical trials.”

The Process

Maria Millan says we are seeing these kinds of change – more collaboration, more transparency –  taking place across the board:

“We see the research in academic institutions that then moved into small companies that are now being approved by the FDA. Academic centers, in conjunction with industry partners, are helping create networks and connections that advance therapies.

This gives us the opportunity to have clinical programs and dialogues about how we can get better, how we can create a more uniform, standard approach that helps us learn from each trial and develop common standards that investigators know have to be in place.

Within the CIRM Alpha Stem Cell Clinic Network the teams coming in can access what we have pulled together already – a database of 20 million patients, a single IRB approval, so that if a cliinical trial is approved for one Alpha Clinic it can also be offered at another.”

Greg Simon says to see the changes really take hold we need to ensure this idea of collaboration starts at the very beginning of the chain:

“If we don’t have a system of basic research where people share data, where people are rewarded for sharing data, journals that don’t lock up the data behind a paywall. If we don’t have that system, we don’t have the ability to move therapies along as quickly as we could.

“Nobody wants to be the last person to die from a cancer that someone figured out a treatment for a year earlier. It’s not that the science is so hard, or the diseases are so hard, it the way we approach them that’s so hard. How do we create the right system?”

More may not necessarily be better

Susan Solomon:

“There are tremendous number of advances moving to the clinic, but I am concerned about the need for more sharing and the sheer number of clinical trials. We have to be smart about how we do our work. There is some low hanging fruit for some clinical trials in the cancer area, but you have to be really careful.”

Greg Simon

“We have too many bad trials, we don’t need more, we need better quality trials.

We have made a lot of progress in cancer. I’m a CLL survivor and had zero problems with the treatment and everything went well.

We have pediatric cancer therapies that turned survival from 10 % to 80%. But the question is why doesn’t more progress happen. We tend to get stuck in a way of thinking and don’t question why it has to be that way. We think of funding because that’s the way funding cycles work, the NIH issues grants every year, so we think about research on a yearly basis. We need to change the cycle.”

Maria Millan says CIRM takes a two pronged approach to improving things, renovating and creating:

“We renovate when we know there are things already in place that can be improved and made better; and we create if there’s nothing there and it needs to be created. We want to be as efficient as we can and not waste time and resources.”

She ended by saying one of the most exciting things today is that the discussion now has moved to how we are going to cover this for patients. Greg Simon couldn’t agree more.

“The biggest predictor of survivability of cancer is health insurance. We need to do more than just develop treatments. We need to have a system that enables people to get access to these therapies.”

CIRM-Funded Scientist is Developing a Stem Cell Therapy that Could Cure HIV

Photo Illustration by the Daily Beast

This week, UCLA scientist Scott Kitchen made the news for his efforts to develop a CIRM-funded stem cell gene therapy that could potentially cure patients infected with HIV. Kitchen’s work was profiled in the Daily Beast, which argued that his “research could significantly up survival rates from the virus.”

Scott Kitchen, UCLA Medicine

Kitchen and a team of scientists at the UCLA David Geffen School of Medicine are genetically modifying blood-forming, hematopoietic stem cells (HSCs) to express chimeric antigen receptors (CARs) that target HIV-infected cells. CARs are protein complexes on the surface of cells that are designed to recognize specific types of cells and are being developed as powerful immunotherapies to fight cancer and HIV infection.

These CAR-expressing HSCs can be transplanted into patients where they develop into immune cells called T cells and natural killer (NK) cells that will destroy cells harboring HIV. This strategy also aims to make patients resistant to HIV because the engineered immune cells will stick around to prevent further HIV infection.

By engineering a patient’s own blood-forming stem cells to produce an unlimited supply of HIV-resistant immune cells that can also eradicate HIV in other cells, Kitchen and his team are creating the possibility for a life-long, functional cure.

Dr. Kelly Shepard, Senior Science Officer of Discovery and Translation Research at CIRM, reflected on significance of Kitchen’s research in an interview:

Kelly Shepard

“This unique approach represents a two-pronged strategy whereby a patient’s own stem cells are engineered not only to be protected from new HIV infection, but also to produce HIV-specific CAR T cells that will seek out and destroy existing and new pools of HIV infection in that patient, ideally leading to a lifelong cure.”

Kitchen and his team are currently testing this stem cell-based CAR-T therapy against HIV in a large-animal model. Their latest findings, which were published recently in the journal PLOS Pathogens, showed that stem cell-derived human CAR T cells were effective at reducing the amount of HIV virus (called the viral load) in their animal-model. They also saw that the CAR T cells survived for more than two years without causing any toxic side effects. This work was funded by an earlier CIRM award led by another CIRM grantee, Dr. Jerome Zack, who is research collaborator of Kitchen’s.

In December 2017, Kitchen received a $1.7 million CIRM Discovery Stage Quest award so that the team can continue to optimize their stem cell CAR T therapy in animal models. Ultimately, they hope to gain insights into how this treatment could be further developed to treat patients with HIV.

Currently, there is no widely available cure for HIV and standard antiretroviral therapies are expensive, difficult for patients to manage and have serious side effects that reduce life expectancy. CIRM has awarded almost $75 million in funding to California scientists focused on developing novel stem cell-based therapies for HIV to address this unmet medical need. Three of these awards support early stage clinical trials, while the rest support earlier stage research projects like Kitchen’s.

CIRM Communications Director, Kevin McCormack, was quoted at the end Daily Beast article explaining CIRM’s strategy for tackling HIV:

“There are a lot of researchers working on developing stem cell therapies for HIV. We fund different approaches because at this stage we don’t know which approach will be most effective, and it may turn out that it’s ultimately a combination of these approaches, or others, that works.”

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

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

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

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

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

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


Novel regenerative drug for osteoarthritis entering clinical trialsThe Scripps Research Institute

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


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

Genetic ‘switches’ behind human brain evolutionScience Daily

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

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

UCLA scientists make sensory nerves from human stem cells for the first time

Being able to tell the difference between hot and cold or feeling the embrace of a loved one are experiences that many of us take for granted in our daily lives. But paralyzed patients who have lost their sense of touch don’t have this luxury.

Sensory nerves are cells in the spinal cord that send signals from outside of the body to the brain where they are translated into senses like touch, temperature and smell. When someone is paralyzed, their sensory nerves can be damaged, preventing these sensory signals from reaching the brain and leaving patients at risk for severe burns or not knowing when they’ve cut themselves because they can’t feel the pain.

A Journey to Restore Touch

A group of scientists led by Dr. Samantha Butler at the  Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research at UCLA are on a research journey to restore the sense of touch in paralyzed patients and people with sensory neuron damage. In their earlier work, which we blogged about back in September, the team discovered that signaling proteins called BMPs played an important role in the development of sensory nerve cells in chicken embryos.

With the help of CIRM-funding, Butler and her team have made significant progress since this earlier study, and today, we bring you an exciting update on their latest findings published in the journal Stem Cell Reports.

Using a similar strategy to their previous study, Butler and her team attempted to make sensory nerve cells from human stem cells in a dish. They exposed human pluripotent stem cells to a specific BMP protein, BMP4, and a chemical called retinoic acid. This combination treatment created two types of sensory nerve cells: Dl1 cells, which allow you to sense your body’s position and movement, and Dl3 cells, which allow you to feel pressure.

Human embryonic stem cell-derived neurons (green) showing nuclei in blue. Left: with retinoic acid added. Right: with retinoic acid and BMP4 added, creating proprioceptive sensory nerve cells (pink). (Image source: UCLA Broad Stem Cell Research Center/Stem Cell Reports)

This is the first time that researchers have reported the ability to make sensory nerve cells from human stem cells. Another important finding was that the UCLA team was able to make sensory nerve cells from both human embryonic stem cells and human induced pluripotent stem cells (iPSCs), which are pluripotent stem cells derived from a patient’s own cells. The latter finding suggests a future where paralyzed patients can be treated with personalized cell-based therapies without the need for immune suppressing drugs.

Feeling the Future

This study, while still in its early stages, is an important step towards a future where paralyzed patients can regain feeling and their sense of touch. Restoring a patient’s ability to move their limbs or walk has dominated the field’s focus, but Butler argues in a UCLA news release that restoring touch is just as important:

Samantha Butler

“The field has for a long time focused on making people walk again. Making people feel again doesn’t have quite the same ring. But to walk, you need to be able to feel and to sense your body in space; the two processes really go hand in glove.”

 

Butler and her team are continuing on their journey to restore touch by transplanting the human sensory nerve cells into the spinal cords of mice to determine whether they can incorporate into the spine and function properly. If the transplanted cells show promise in animal models, the team will further develop this cell-based therapy for clinical trials.

Butler concluded,

“This is a long path. We haven’t solved how to restore touch but we’ve made a major first step by working out some of these protocols to create sensory interneurons.”

UCLA scientists on track to develop a stem cell replacement therapy for Duchenne Muscular Dystrophy

Muscle cells generated by April Pyle’s Lab at UCLA.

Last year, we wrote about a CIRM-funded team at UCLA that’s on a mission to develop a stem cell treatment for patients with Duchenne muscular dystrophy (DMD). Today, we bring you an exciting update on this research just in time for the holidays (Merry Christmas and Happy Hanukkah and Kwanza to our readers!).

DMD is a deadly muscle wasting disease that primarily affects young boys and young men. The UCLA team is trying to generate better methods for making skeletal muscle cells from pluripotent stem cells to regenerate the muscle tissue that is lost in patients with the condition. DMD is caused by genetic mutations in the dystrophin gene, which codes for a protein that is essential for skeletal muscle function. Without dystrophin protein, skeletal muscles become weak and waste away.

In their previous study, the UCLA team used CRISPR gene editing technology to remove dystrophin mutations in induced pluripotent stem cells (iPSCs) made from the skin cells of DMD patients. These corrected iPSCs were then matured into skeletal muscle cells that were transplanted into mice. The transplanted muscle cells successfully produced dystrophin protein – proving for the first time that DMD mutations can be corrected using human iPSCs.

A Step Forward

The team has advanced their research a step forward and published a method for making skeletal muscle cells, from DMD patient iPSCs, that look and function like real skeletal muscle tissue. Their findings, which were published today in the journal Nature Cell Biology, address a longstanding problem in the field: not being able to make stem cell-derived muscle cells that are mature enough to model DMD or to be used for cell replacement therapies.

Dr. April Pyle, senior author on the study and Associate Professor at the Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research at UCLA explained in a news release:

April Pyle, UCLA.

“We have found that just because a skeletal muscle cell produced in the lab expresses muscle markers, doesn’t mean it is fully functional. For a stem cell therapy for Duchenne to move forward, we must have a better understanding of the cells we are generating from human pluripotent stem cells compared to the muscle stem cells found naturally in the human body and during the development process.”

By comparing the proteins expressed on the cell surface of human fetal and adult muscle cells, the team identified two proteins, ERBB3 and NGFR, that represented a regenerative population of skeletal muscle cells. They used these two markers to isolate these regenerative muscle cells, but found that the muscle fibers they created in a lab dish were smaller than those found in human muscle.

First author, Michael Hicks, discovered that using a drug to block a human developmental signaling pathway called TGF Beta pushed these ERBB3/NGFR cells past this intermediate stage and allowed them to mature into functional skeletal muscle cells similar to those found in human muscle.

Putting It All Together

In their final experiments, the team combined the new stem cell techniques developed in the current study with their previous work using CRISPR gene editing technology. First, they removed the dystrophin mutations in DMD patient iPSCs using CRISPR. Then, they coaxed the iPSCs into skeletal muscle cells in a dish and isolated the regenerative cells that expressed ERBB3 and NGFR. Mice that lacked the dystrophin protein were then transplanted with these cells and were simultaneously given an injection of a TGF Beta blocking drug.

The results were exciting. The transplanted cells were able to produce human dystrophin and restore the expression of this protein in the Duchenne mice.

Skeletal muscle cells isolated using the ERBB3 and NGFR surface markers (right) restore human dystrophin (green) after transplantation significantly greater than previous methods (left). (Image courtesy of UCLA)

Dr. Pyle concluded,

“The results were exactly what we’d hoped. This is the first study to demonstrate that functional muscle cells can be created in a laboratory and restore dystrophin in animal models of Duchenne using the human development process as a guide.”

In the long term, the UCLA team hopes to translate this research into a patient-specific stem cell therapy for DMD patients. In the meantime, the team will use funding from a recent CIRM Quest award to make skeletal muscle cells that can regenerate long-term in response to chronic injury in hopes of developing a more permanent treatment for DMD.

The UCLA study discussed in this blog received funding from Discovery stage CIRM awards, which you can read more about here and here.