New findings about muscle stem cells reveals the potential for growing replacement organs

Chrissa Kioussi’s group at Oregon State University has made exciting advances in further unraveling the scientific mysteries of stem cells. In work detailed in Scientific Reports, this group found that muscle-specific stem cells actually have the ability to make multiple different cell types.

muscle_bicep_FaceBook_shutterstock_162592241

Pumping up our knowledge about muscle stem cells

Initially, this group was interested in understanding how gene expression changes during embryonic development of skeletal muscle. To understand this process, they labeled muscle stem cells with a kind of fluorescent dye, called GFP, which allowed them to isolate these cells at different stages of development.  Once isolated, they determined what genes were being expressed by RNA sequencing. Surprisingly, they found that in addition to genes involved in muscle formation, they also identified activation of genes involved in the blood, nervous, immune and skeletal systems.

This work is particularly exciting, because it suggests the existence of stem cell “pockets,” or stem cells that are capable of not only making a specific cell type, but an entire organ system.

In a press release, Dr. Kioussi said:

chrissa_kioussi

Chrissa Kioussi, PhD

“That cell populations can give rise to so many different cell types, we can use it at the development stage and allow it to become something else over time… We can identify these cells and be able to generate not one but four different organs from them — this is a prelude to making body parts in a lab.” 

This study is particularly exciting because it gives more credence to the idea that entire limbs can be reconstructed from a small group of stem cells. Such advances could have enormous meaning for individuals who have lost body parts due to amputation or disease.

Using biological “codes” to generate neurons in a dish

BrainWavesInvestigators at the Scripps Research Institute are making brain waves in the field of neuroscience. Until now, neuroscience research has largely relied on a variety of animal models to understand the complexities of various brain or neuronal diseases. While beneficial for many reasons, animal models do not always allow scientists to understand the precise mechanism of neuronal dysfunction, and studies done in animals can often be difficult to translate to humans. The work done by Kristin Baldwin’s group, however, is revolutionizing this field by trying to re-create this complexity in a dish.

One of the primary hurdles that scientists have had to overcome in studying neuronal diseases, is the impressive diversity of neuronal cell types that exist. The exact number of neuronal subtypes is unknown, but scientists estimate the number to be in the hundreds.

While neurons have many similarities, such as the ability to receive and send information via chemical cues, they are also distinctly specialized. For example, some neurons are involved in sensing the external environment, whereas others may be involved in helping our muscles move. Effective medical treatment for neuronal diseases is contingent on scientists being able to understand how and why specific neuronal subtypes do not function properly.

In a study in the journal Nature, partially funded by CIRM, the scientists used pairs of transcription factors (proteins that affect gene expression and cell identity), to turn skin stem cells into neurons. These cells both physically looked like neurons and exhibited characteristic neuronal properties, such as action potential generation (the ability to conduct electrical impulses). Surprisingly, the team also found that they were able to generate neurons that had unique and specialized features based on the transcription factors pairs used.

The ability to create neuronal diversity using this method indicates that this protocol could be used to recapitulate neuronal diversity outside of the body. In a press release, Dr. Baldwin states:

KristinBaldwin

Kristin Baldwin, PhD

“Now we can be better genome detectives. Building up a database of these codes [transcription factors] and the types of neurons they produce can help us directly link genomic studies of human brain disease to a molecular understanding of what goes wrong with neurons, which is the key to finding and targeting treatments.”

These findings provide an exciting and promising tool to more effectively study the complexities of neuronal disease. The investigators of this study have made their results available on a free platform called BioGPS in the hopes that multiple labs will delve into the wealth of information they have opened up. Hopefully, this system will lead to more rapid drug discovery for disease like autism and Alzheimer’s

A road trip to the Inland Empire highlights a hot bed of stem cell research

UCR#1

Gillian Wilson, Interim Vice Chancellor, Research, UC Riverside welcomes people to the combined Research Roadshow and Patient Advocate event

It took us longer than it should have to pay a visit to California’s Inland Empire, but it was definitely worth the wait. Yesterday CIRM’s Roadshow went to the University of California at Riverside (UCR) to talk to the community there – both scientific and public – about the work we are funding and the progress being made, and to hear from them about their hopes and plans for the future.

As always when we go on the road, we learn so much and are so impressed by everyone’s passion and commitment to stem cell research and their belief that it’s changing the face of medicine as we know it.

Dr. Deborah Deas, the Dean of the UC Riverside School of Medicine and a CIRM Board member, kicked off the proceedings by saying:

“Since CIRM was created in 2004 the agency has been committed to providing the technology and research to meet the unmet needs of the people of California.

On the Board I have been impressed by the sheer range and number of diseases targeted by the research CIRM is funding. We in the Inland Empire are playing our part. With CIRM’s help we have developed a strong program that is doing some exciting work in discovery, education and translational research.”

IMG_1245

CIRM’s Dr. Maria Millan at the Roadshow Patient Advocate event

CIRM’s President and CEO, Dr. Maria T. Millan, and our Board Chair, Jonathan Thomas then gave a quick potted history of CIRM and the projects we are funding. They highlighted how we are creating a pipeline of products from the Discovery, or basic level of research, through to the 45 clinical trials we are funding.

They also talked about the Alpha Clinic Network, based at six highly specialized medical centers around California, that are delivering stem cell therapies and sharing the experiences and knowledge learned from these trials to improve their ability to help patients and advance the field.

Researchers from both UCR then gave a series of brief snapshots of the innovative work they are doing:

  • Looking at new, more efficient and effective ways of expanding the number of human embryonic stem cells in the laboratory to create the high volume of cells needed for therapies.
  • Using biodegradable materials to help repair and regenerate tissue for things as varied as bone and cartilage repair or nerve restoration.
  • Exploring the use of epigenetic factors, things that switch genes on and off, to try and find ways to make repairs inside the body, rather than taking the cells outside the body, re-engineering them and returning them to the body. In essence, using the body as its own lab to manufacture replacement.

Another CIRM Board member, Linda Malkas, talked about the research being done at City of Hope (COH), where she is the associate chair of the Department of Molecular and Cellular Biology, calling it an “engine for discovery that has created the infrastructure and attracted people with an  amazing set of skills to bring forward new therapeutics for patients.”

She talked about how COH is home to one of the first Alpha Clinics that CIRM funded, and that it now has 27 active clinical trials, with seven more pending and 11 more in the pipeline.

“In my opinion this is one of the crown jewels of the CIRM program. CIRM is leading the nation in showing how to put together a network of specialized clinics to deliver these therapies. The National Institutes of Health (NIH) came to CIRM to learn from them and to talk about how to better move the most promising ideas and trials through the system faster and more efficiently.”

Dr. Malkas also celebrated the partnership between COH and UCR, where they are collaborating on 19 different projects, pooling their experience and expertise to advance this research.

Finally, Christine Brown, PhD, talked about her work using chimeric antigen receptor (CAR) T cells to fight cancer stem cells. In this CIRM-funded clinical trial, Dr. Brown hopes to re-engineer a patient’s T cells – a key cell of the immune system – to recognize a target protein on the surface of brain cancer stem cells and kill the tumors.

It was a packed event, with an overflow group watching on monitors outside the auditorium. The questions asked afterwards didn’t just focus on the research being done, but on research that still needs to be done.

One patient advocate couple asked about clinics offering stem cell therapies for Parkinson’s disease, wondering if the therapies were worth spending more than $10,000 on.

Dr. Millan cautioned against getting any therapy that wasn’t either approved by the Food and Drug Administration (FDA) or wasn’t part of a clinical trial sanctioned by the FDA. She said that in the past, these clinics were mostly outside the US (hence the term “stem cell tourism”) but increasingly they are opening up centers here in the US offering unproven and unapproved therapies.

She said there are lots of questions people need to ask before signing up for a clinical trial. You can find those questions here.

The visit was a strong reminder that there is exciting stem cell research taking place all over California and that the Inland Empire is a key player in that research, working on projects that could one day have a huge impact in changing people’s lives, even saving people’s lives.

 

Stem cell study holds out promise for kidney disease

Kidney failure

Image via youtube.com

Kidney failure is the Rodney Dangerfield of diseases, it really doesn’t get the respect it deserves. An estimated 660,000 Americans suffer from kidney failure and around 47,000 people die from it every year. That’s more than die from breast or prostate cancer. But now a new study has identified a promising stem cell candidate that could help in finding a way to help repair damaged kidneys.

Kidneys are the body’s waste disposal system, filtering our blood and cleaning out all the waste products. Our kidneys have a limited ability to help repair themselves but if someone suffers from chronic kidney disease then their kidneys are slowly overwhelmed and that leads to end stage renal disease. At that point the patient’s options are limited to dialysis or an organ transplant.

Survivors hold out hope

Italian researchers had identified some cells in the kidneys that showed a regenerative ability. These cells, which were characterized by the expression of a molecule called CD133, were able to survive injury and create different types of kidney cells.

Researchers at the University of Torino in Italy decided to take these findings further and explore precisely how CD133 worked and if they could take advantage of that and use it to help repair damaged kidneys.

In their findings, published in the journal Stem Cells Translational Medicine, the researchers began by working with a chemotherapy drug called cisplatin, which is used against a broad range of cancers but is also known to cause damage to kidneys in around one third of all patients. The team found that CD133 was an important factor in helping those damaged kidneys recover. They also found that CD133 prevents aging of kidney progenitor cells, the kind of cell needed to help create new cells to repair the kidneys in future.

Hope for further research

The finding opens up a number of possible lines of research, including exploring whether infusions of CD133 could help patients whose kidneys are no longer able to produce enough of the molecule to help repair damage.

In an interview in DD News, Dr. Anthony Atala, Director of the Wake Forest Institute for Regenerative Medicine – praised the research:

“This is an interesting and novel finding. Because the work identifies mechanisms potentially involved in the repair of tissue after injury, it suggests the possibility of new therapies for tissue repair and regeneration.”

CIRM is funding several projects targeting kidney disease including four clinical trials for kidney failure. These are all late-stage kidney failure problems so if the CD133 research lives up to its promise it might be able to help people at an earlier stage of disease.

Say Hello to CIRM’s New Active Awards Portfolio Dashboard (Video Included!)

It takes a lot of time, money and effort to develop a promising stem cell research idea into an effective treatment that can help patients. Oftentimes, you don’t hear about the early-stage research that goes into developing a particular treatment until it reaches the clinic.

CIRM recognizes the importance of investing in all stages of stem cell research and has an impressive portfolio of over 160 active projects spanning discovery, translation, and clinical-stage research.

To help you understand the breadth of our funding efforts, and to highlight our expanding research pipeline, we’ve created the Active Awards Portfolio Dashboard on our website. This interactive tool makes it easy to search through the active research projects that we’re currently funding, and filter these projects by disease focus, technology type or stage of research.

Watch the short video below to learn more about our new Dashboard and how to use it.

The Active Awards Dashboard reflects our Agency’s commitment to investing in the full range of stem cell research and to helping the most promising research projects advance to the next level.

For those of you interested in learning more about the 45 active clinical trials we’re funding, be sure to check out the companion Clinical Trials Dashboard on our website, featured previously on the Stem Cellar blog.

Cold temps nudge stem cells to boost “good” fat, may point to obesity remedies

Newborn babies may not be able to walk or talk but they can do something that makes adults very jealous: burn extra calories without exercising. This feat is accomplished with the help of brown fat which is abundant in infants (and hibernating animals) but barely detectable in adults. However, a new study in Scientific Reports shows that cold temperatures can nudge mesenchymal stem cells – found in the bone marrow – toward a brown fat cell fate, a finding that may uncover new strategies for combating obesity and other metabolic diseases.

Brown-and-White-adipose-tissue

Side by side comparision of brown fat, or adipose, cells and white fat cells.
Image: AHAJournals.org

So, what’s so magical about cells that carry brown fat, the so-called “good” fat? Like the more common “bad’ white fat cells, brown fat cells store energy in the form of fat droplets and can burn that energy to meet the demands of the body’s functions like pumping the heart and moving the limbs. But brown fat can also burn calories independent of the body’s energy needs. It’s like stepping on a car’s clutch and gas pedal at the same time: the body burns the fuel but doesn’t do any usable work, so those calories just dissipate as heat. This source of heat is critical for babies because they are not yet able to regulate their own body temperature and lose heat rapidly.

Scientists have known for quite some time that cold temperatures stimulate the production of brown fat but didn’t know exactly why (a CIRM-funded study we blogged about last week identified a protein that also boosts brown fat production). In the current study, a team at the University of Nottingham in the U.K., examined the effect of cold temperature on the fate of bone marrow-derived mesenchymal stem cells which give rise to both white and brown fat tissue as well as bone, cartilage and muscle. Petri dishes containing the cells were placed in incubators at 89°F (32°C) and stimulated to become fat cells. That may not seem cold, but if your core body temperature went that low (instead of the normal 98.6F) you would be beyond shivering, close to collapsing and in need of an emergency room.

With that temperature drop, the researcher observed a “browning” of the stem cells towards a brown fat cell fate. The brown color, in case you’re interested, is cause by the increased number of mitochondria within the cells. These “power factories” of the cell are the source of the heat generation. This result has promising implications for adults struggling with their body weight.

virginiesottile

Virginie Sottile

“The good news from these results is that our cells are not pre-programmed to form bad fat and our stem cells can respond if we apply the right change in lifestyle,” explained Dr Virginie Sottile, one of the team leaders on the project, in a press release.

 

Ok, I know what you’re thinking: moving to Antarctica to lose weight is not my idea of a doable lifestyle change! That’s a point well taken. But the ultimate goal for the researchers is to use this cell system to more carefully study the cellular events that occur under reduced temperatures. This type of inquiry could help identify drug targets that mimic the effects of colder temperatures:

“The next step in our research is to find the actual switch in the cell that makes it respond to the change of temperature in its environment,” said Dr Sottile. “That way, we may be able to identify drugs or molecules that people could swallow that may artificially activate the same gene and trick the body into producing more of this good fat.”

A shot in the arm for people with bad knees

knee

Almost every day I get an email or phone call from someone asking if we have a stem cell therapy for bad knees. The inquiries are from people who’ve been told they need surgery to replace joints damaged by age and arthritis. They’re not alone. Every year around 600,000 Americans get a knee replacement. That number is expected to rise to three million by 2030.

Up till now my answer to those calls and emails has been ‘I’m sorry, we don’t have anything’. But a new CIRM-funded study from USC stem cell scientist Denis Evseenko says that may not always be the case.

JointCartilege_nancy_liu-824x549

The ability to regenerate joint cartilage cells instead of surgically replacing joints would be a big boon for future patients. (Photo/Nancy Liu, Denis Evseenko Lab, USC Stem Cell)

Evseenko and his team have discovered a molecule they have called Regulator of Cartilage Growth and Differentiation or RCGD 423. This cunning molecule works in two different ways. One is to reduce the inflammation that many people with arthritis have in their joints. The second is to help stimulate the regeneration of the cartilage destroyed by arthritis.

When they tested RCGD 423 in rats with damaged cartilage, the rats cartilage improved. The study is published in the Annals of Rheumatic Diseases.

In an article in USC News, Evseenko, says there is a lot of work to do but that this approach could ultimately help people with osteoarthritis or juvenile arthritis.

“The goal is to make an injectable therapy for an early to moderate level of arthritis. It’s not going to cure arthritis, but it will delay the progression of arthritis to the damaging stages when patients need joint replacements, which account for a million surgeries a year in the U.S.”

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

17yamanaka-master768

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.

 

 

 

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

Sergiu Pasca, Stanford University

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

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

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

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

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

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


Related Links:

Creating a platform to help transplanted stem cells survive after a heart attack

heart

Developing new tools to repair damaged hearts

Repairing, even reversing, the damage caused by a heart attack is the Holy Grail of stem cell researchers. For years the Grail seemed out of reach because the cells that researchers transplanted into heart attack patients didn’t stick around long enough to do much good. Now researchers at Stanford may have found a way around that problem.

In a heart attack, a blockage cuts off the oxygen supply to muscle cells. Like any part of our body starved off oxygen the muscle cells start to die, and as they do the body responds by creating a layer of scars, effectively walling off the dead tissue from the surviving healthy tissue.  But that scar tissue makes it harder for the heart to effectively and efficiently pump blood around the body. That reduced blood flow has a big impact on a person’s ability to return to a normal life.

In the past, efforts to transplant stem cells into the heart had limited success. Researchers tried pairing the cells with factors called peptides to help boost their odds of surviving. That worked a little better but most of the peptides were also short-lived and weren’t able to make a big difference in the ability of transplanted cells to stick around long enough to help the heart heal.

Slow and steady approach

Now, in a CIRM-funded study published in the journal Nature Biomedical Engineering, a team at Stanford – led by Dr. Joseph Wu – believe they have managed to create a new way of delivering these cells, one that combines them with a slow-release delivery mechanism to increase their chances of success.

The team began by working with a subset of bone marrow cells that had been shown in previous studies to have what are called “pro-survival factors.” Then, working in mice, they identified three peptides that lived longer than other peptides. That was step one.

Step two involved creating a matrix, a kind of supporting scaffold, that would enable the researchers to link the three peptides and combine them with a delivery system they hoped would produce a slow release of pro-survival factors.

Step three was seeing if it worked. Using fluorescent markers, they were able to show, in laboratory tests, that unlinked peptides were rapidly released over two or three days. However, the linked peptides had a much slower release, lasting more than 15 days.

Out of the lab and into animals

While these petri dish experiments looked promising the big question was could this approach work in an animal model and, ultimately, in people. So, the team focused on cardiac progenitor cells (CPCs) which have shown potential to help repair damaged hearts, but which also have a low survival rate when transplanted into hearts that have experienced a heart attack.

The team delivered CPCs to the hearts of mice and found the cells without the pro-survival matrix didn’t last long – 80 percent of the cells were gone four days after they were injected, 90 percent were gone by day ten. In contrast the cells on the peptide-infused matrix were found in large numbers up to eight weeks after injection. And the cells didn’t just survive, they also engrafted and activated the heart’s own survival pathways.

Impact on heart

The team then tested to see if the treatment was helping improve heart function. They did echocardiograms and magnetic resonance imaging up to 8 weeks after the transplant surgery and found that the mice treated with the matrix combination had a statistically improved left ventricular function compared to the other mice.

Jayakumar Rajadas, one of the authors on the paper told CIRM that, because the matrix was partly made out of collagen, a substance the FDA has already approved for use in people, this could help in applying for approval to test it in people in the future:

“This paper is the first comprehensive report to demonstrate an FDA-compliant biomaterial to improve stem cell engraftment in the ischemic heart. Importantly, the biomaterial is collagen-based and can be readily tested in humans once regulatory approval is obtained.”