Building embryo-like cells in the lab

Dr. Magdalena Zernicka-Goetz: Photo courtesy Caltech

Human embryonic stem cells (hESCs) have many remarkable properties, not the least of which is their ability to turn into every other kind of cell in our body. But there are limits to what researchers can do with embryonic stem cells. One issue is that there aren’t always hESCs available – they come from eggs donated by couples who have undergone in vitro fertilization. Another is that researchers can only develop these cells in the laboratory for 14 days (though that rule may be changing).

Now researchers at Caltech have developed a kind of hESC-in-a-dish that could help make it easier to answer questions about human development without the need to wait for a new line of hESCs.

The team, led by Magdalena Zernicka-Goetz, used a line of expanded pluripotent cells (EPSCs), originally derived from a human embryo, to create a kind of 3D model that mimics some of the activities of an embryo.

The cool thing about these cells is that, because they were originally derived from an embryo, they retain some “memory” of how they are supposed to work. In a news release Zernicka-Goetz says this enables them to display elements of both polarization and cavitation, early crucial phases in the development of a human embryo.

“The ability to assemble the basic structure of the embryo seems to be a built-in property of these earliest embryonic cells that they are simply unable to ‘forget.’ Nevertheless, either their memory is not absolutely precise or we don’t yet have the best method of helping the cells recover their memories. We still have further work to do before we can get human stem cells to achieve the developmental accuracy that is possible with their equivalent mouse stem cell counterparts.”

Being able to create these embryo-like elements means researchers can generate cells in large numbers and won’t be so dependent on donated embryos.

In the study, published in the journal Nature Communications, the researchers say this could help them develop a deeper understanding of embryonic development.

Understanding human development is of fundamental biological and clinical importance. Despite its significance, mechanisms behind human embryogenesis remain largely unknown…. this stem cell platform provides insights into the design of stem cell models of embryogenesis.

Creating a diverse group of future scientists

Students in CIRM’s Bridges program showing posters of their work

If you have read the headlines lately, you’ll know that the COVID-19 pandemic is having a huge impact on the shipping industry. Container vessels are forced to sit out at anchor for a week or more because there just aren’t enough dock workers to unload the boats. It’s a simple rule of economics, you can have all the demand you want but if you don’t have the people to help deliver on the supply side, you are in trouble.

The same is true in regenerative medicine. The field is expanding rapidly and that’s creating a rising demand for skilled workers to help keep up. That doesn’t just mean scientists, but also technicians and other skilled individuals who can ensure that our ability to manufacture and deliver these new therapies is not slowed down.

That’s one of the reasons why CIRM has been a big supporter of training programs ever since we were created by the voters of California when they approved Proposition 71. And now we are kick-starting those programs again to ensure the field has all the talented workers it needs.

Last week the CIRM Board approved 18 programs, investing more than $86 million, as part of the Agency’s Research Training Grants program. The goal of the program is to create a diverse group of scientists with the knowledge and skill to lead effective stem cell research programs.

The awards provide up to $5 million per institution, for a maximum of 20 institutions, over five years, to support the training of predoctoral graduate students, postdoctoral trainees, and/or clinical trainees.

This is a revival of an earlier Research Training program that ran from 2006-2016 and trained 940 “CIRM Scholars” including:

• 321 PhD students
• 453 Postdocs
• 166 MDs

These grants went to academic institutions from UC Davis in Sacramento to UC San Diego down south and everywhere in-between. A 2013 survey of the students found that most went on to careers in the industry.

  • 56% continued to further training
  • 14% advanced to an academic research faculty position
  • 10.5% advanced to a biotech/industry position
  • 12% advanced to a non-research position such as teaching, medical practice, or foundation/government work

The Research Training Grants go to:

AWARDINSTITUTIONTITLEAMOUNT
EDUC4-12751Cedars-SinaiCIRM Training Program in Translational Regenerative Medicine    $4,999,333
EDUC4-12752UC RiversideTRANSCEND – Training Program to Advance Interdisciplinary Stem Cell Research, Education, and Workforce Diversity    $4,993,115
EDUC4-12753UC Los AngelesUCLA Training Program in Stem Cell Biology    $5 million
EDUC4-12756University of Southern CaliforniaTraining Program Bridging Stem Cell Research with Clinical Applications in Regenerative Medicine    $5 million
EDUC4-12759UC Santa CruzCIRM Training Program in Systems Biology of Stem Cells    $4,913,271
EDUC4-12766Gladstone Inst.CIRM Regenerative Medicine Research Training Program    $5 million
EDUC4-12772City of HopeResearch Training Program in Stem Cell Biology and Regenerative Medicine    $4,860,989
EDUC4-12782StanfordCIRM Scholar Training Program    $4,974,073
EDUC4-12790UC BerkeleyTraining the Next Generation of Biologists and Engineers for Regenerative Medicine    $4,954,238
EDUC4-12792UC DavisCIRM Cell and Gene Therapy Training Program 2.0    $4,966,300
EDUC4-12802Children’s Hospital of Los AngelesCIRM Training Program for Stem Cell and Regenerative Medicine Research    $4,999,500
EDUC4-12804UC San DiegoInterdisciplinary Stem Cell Training Grant at UCSD III    $4,992,446
EDUC4-12811ScrippsTraining Scholars in Regenerative Medicine and Stem Cell Research    $4,931,353
EDUC4-12812UC San FranciscoScholars Research Training Program in Regenerative Medicine, Gene Therapy, and Stem Cell Research    $5 million
EDUC4-12813Sanford BurnhamA Multidisciplinary Stem Cell Training Program at Sanford Burnham Prebys Institute, A Critical Component of the La Jolla Mesa Educational Network    $4,915,671  
EDUC4-12821UC Santa BarbaraCIRM Training Program in Stem Cell Biology and Engineering    $1,924,497
EDUC4-12822UC IrvineCIRM Scholars Comprehensive Research Training Program  $5 million
EDUC4-12837Lundquist Institute for Biomedical InnovationStem Cell Training Program at the Lundquist Institute    $4,999,999

These are not the only awards we make to support training the next generation of scientists. We also have our SPARK and Bridges to Stem Cell Research programs. The SPARK awards are for high school students, and the Bridges program for graduate or Master’s level students.

A new approach to a deadly childhood cancer

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Cancers of the blood, bone marrow and lymph nodes (also called hematologic malignancies) are the most common form of cancer in children and young adults. Current treatments can be effective but can also pose life-threatening health risks to the child. Now researchers at Stanford have developed a new approach and the Board of the California Institute for Regenerative Medicine (CIRM) voted to support that approach in a clinical trial.

The Board approved investing $11,996,634 in the study, which is the Stem Cell Agency’s 76th clinical trial.

The current standard of care for cancers such as acute leukemias and lymphomas is chemotherapy and a bone marrow (also called HSCT) transplant. However, without a perfectly matched donor the risk of the patient’s body rejecting the transplant is higher. Patients may also be at greater risk of graft vs host disease (GVHD), where the donor cells attack the patient’s body. In severe cases GVHD can be life-threatening.

Dr. Maria Grazia Roncarlo: Photo courtesy Stanford

Dr. Maria Grazia Roncarolo and her team at Stanford will test an immunotherapy cell approach using a therapy that is enriched with specialized immune cells called type 1 regulatory T (Tr1) cells. These cells will be infused into the patient following the bone marrow transplant. Both the Tr1 cells and the bone marrow will come from the same donor. The hope is this will help provide the patient’s immune system with these regulatory cells to combat life-threatening graft versus host disease and increase the success of treatment and bone marrow (HSCT) transplant.

“Every year around 500 children receive stem cell transplants in California, and while many children do well, too many experiences a rejection of the transplant or a relapse of the cancer,” says Dr. Maria T. Millan, President and CEO of CIRM. “Finding an improved therapy for these children means a shorter stay in the hospital, less risk of the need for a second transplant, and a greater quality of life for the child and the whole family.”

The CIRM Board has previously approved funding for 12 other clinical trials targeting cancers of the blood. You can read about them here.

Them bones them bones them dry bones – and how to help repair them

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Broken bones

People say that with age comes wisdom, kindness and confidence. What they usually don’t say is that it also comes with aches and pains and problems we didn’t have when we were younger. For example, as we get older our bones get thinner and more likely to break and less likely to heal properly.

That’s a depressing opening paragraph isn’t it. But don’t worry, things get better from here because new research from Germany has found clues as to what causes our bones to become more brittle, and what we can do to try and stop that.

Researchers at the Max Planck Institute for Biology of Ageing and CECAD Cluster of Excellence for Ageing Research at the University of Cologne have identified changes in stem cells from our bone marrow that seem to play a key role in bones getting weaker as we age.

To explain this we’re going to have to go into the science a little, so bear with me. One of the issues the researchers focused on is the role of epigenetics, this is genetic information that doesn’t change the genes themselves but does change their activity. Think of it like a light switch. The switch doesn’t change the bulb, but it does control when it’s on and when it’s off. So this team looked at the epigenome of MSCs, the stem cells found in the bone marrow. These cells play a key role in the creation of cartilage, bone and fat cells.

In a news release, Dr. Andromachi Pouikli, one of the lead researchers in the study, says these MSCs don’t function as well as we get older.

“We wanted to know why these stem cells produce less material for the development and maintenance of bones as we age, causing more and more fat to accumulate in the bone marrow. To do this, we compared the epigenome of stem cells from young and old mice. We could see that the epigenome changes significantly with age. Genes that are important for bone production are particularly affected.”

So, they took some stem cells from the bone marrow of mice and tested them with a solution of sodium acetate. Now sodium acetate has a lot of uses, including being used in heating pads, hand warmers and as a food seasoning, but in this case the solution was able to make it easier for enzymes to get access to genes and boost their activity.

“This treatment impressively caused the epigenome to rejuvenate, improving stem cell activity and leading to higher production of bone cells,” Pouikli said.

So far so good. But does this work the same way in people? Maybe so. The team analyzed MSCs from people who had undergone hip surgery and found that they showed the same kind of age-related changes as the cells from mice.

Clearly there’s a lot more work to do before we can even think about using this finding as a solution to aging bones. But it’s an encouraging start.

The study is published in the journal Nature Aging.

Lack of diversity impacts research into Alzheimer’s and dementia

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A National Institutes of Allergy and Infectious Diseases clinical trial admissions coordinator collects information from a volunteer to create a medical record. Credit: NIAID

Alzheimer’s research has been in the news a lot lately, and not for the right reasons. The controversial decision by the Food and Drug Administration (FDA) to approve the drug Aduhelm left many people wondering how, when, or even if it should be used on people battling Alzheimer’s disease. Now a new study is raising questions about many of the clinical trials used to test medications like Aduhelm.

The research, published in the journal Jama Neurology, looked at 302 studies on dementia published in 2018 and 2019. Most of these studies were carried out in North America or Europe, and almost 90 percent of those studied were white.

In an accompanying editorial in the journal, Dr. Cerise Elliott, PhD, of the National Institute on Aging (NIA) in Bethesda, Maryland, and co-authors wrote that this limited the value of the studies: “This, combined with the fact that only 22% of the studies they analyzed even reported on race and ethnicity, and of those, a median 89% of participants were white, reflects the fact that recruitment for research participation is challenging; however, it is unacceptable that studies continue to fail to report participant demographics and that publishers allow such omissions.”

That bias is made all the more glaring by the fact that recent data from the Centers for Disease Control and Prevention shows that among people 65 and older, the Black community has the highest prevalence of Alzheimer’s disease and related dementias (13.8%), followed by Latinx (12.2%), non-Hispanic white (10.3%), American Indian and Alaskan Native (9.1%), and Asian and Pacific Islander (8.4%) populations.

The researchers admitted that the limited sample size – more than 40 percent of the studies they looked at included fewer than 50 patients – could have impacted their findings. Even so this clearly suggests there is a huge divide between the people at greatest risk of developing Alzheimer’s, or some other form of dementia, and the people being studied.

In the editorial, Elliott and his colleagues wrote that without a more diverse and balanced patient population this kind of research: “will continue to underrepresent people most affected by the disease and perpetuate systems that exclude important valuable knowledge about the disease.”


There are more details on this in Medpage Today.

An editorial in the New England Journal of Medicine highlights how this kind of bias is all too common in medical research.

“For years, the Journal has published studies that simply do not include enough participants from the racial and ethnic groups that are disproportionately affected by the illnesses being studied to support any conclusions about their treatment. In the United States, for example, Black Americans have high rates of hypertension and chronic kidney disease, Hispanic Americans have the highest prevalence of nonalcoholic fatty liver disease, Native Americans are disproportionately likely to have metabolic syndrome, and Asian Americans are at particular risk for hepatitis B infection and subsequent cirrhosis, but these groups are frequently underrepresented in clinical trials and cohort studies.”

“For too long, we have tolerated conditions that actively exclude groups from critical resources in health care delivery, research, and education. This exclusion has tragic consequences and undermines confidence in the institutions and the people who are conducting biomedical research. And clinicians cannot know how to optimally prevent and treat disease in members of communities that have not been studied.”

The encouraging news is that, finally, people are recognizing the problem and trying to come up with ways to correct it. The not so encouraging is that it took a pandemic to get us to pay attention.

At CIRM we are committed to being part of the solution. We are now requiring everyone who applies to us for funding to have a written plan on Diversity, Equity and Inclusion, laying out how their work will reflect the diversity of California. We know this will be challenging for all of us. But the alternative, doing nothing, is no longer acceptable.

Using a stem cell’s journey to teach kids science

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As far as Aldo Pourchet is concerned you are never too young to learn about stem cells. Aldo should know. He’s a molecular and cellular biologist and the co-founder and CEO of Omios Bio, which develops immunotherapies for cancer, infectious and inflammatory diseases.

Aldo Pourchet

And now Aldo is the author of a children’s book about stem cells. The book is “Nano’s Journey! A Little Stem Cell Visits the Heart and Lungs.” It’s the story of Nano, a stem cell who doesn’t know what kind of cell she wants to be when she grows up, so she goes on a journey through the body, exploring all the different kinds of cell she could be.

It’s a really sweet book, beautifully illustrated, and written in a charming way to engage children between the ages of 5 and 8. I asked Aldo what made him want to write a book like this.

“I was interested in providing very general knowledge such as the principle of life, the basic logics of nature and at the same time to entertain. It was very important for it not to be a textbook.

“Why Stem cells? Because it is the most fascinating biology and they are at the origin of an organism and throughout its life play an essential role. They evolve and transform, so they have a story that unfolds. An analogy with children maybe. It’s easy to imagine children are like stem cells, trying to decide who they are, while adults are like differentiated cells because they have already decided.

“For the kids to appropriate the story, I thought that humanizing cells was important.  I wanted children to identify themselves with the cells and especially Nano, the little girl main character. It’s a book written for the children, in the first place. We tell the story at their level. Not try to bring them up to the level of life science.

Aldo says right from the start he had a clear idea of who he wanted the lead character to be.

“I think the world needs more female leaders, more female voices and influence in general and in every domain. So quite early it became natural for me that Nano would be a girl and also would have a strong character, curious and adventurous.

“Blasto came later because I was looking for a companion to share the adventure with Nano. Blasto is a fibroblast so he is not supposed to leave the Bone Marrow but fibroblasts are everywhere in our organism so I thought it was an acceptable stretch.

The drawings in the book are delightful, colorful and fun. Aldo says he had some ideas, rounded shapes for the cells for example and a simple design that reflected the fact that there are no lines in nature. Illustrator Jen Yoon took it from there:

“Based on Aldo’s direction and imagination, I envisioned the style like drawings on a chalkboard. Soft curves with rough textures. After that everything went smoothly. Following Nano’s journey with my iPad pencil, it felt like a boat ride at an amusement park.”

The books are written to be read aloud by parents, adults and teachers to kids. But, spoiler alert, we don’t find out what cell Nano decides to be in this book. She’s going to have more adventures in other books before she makes up her mind.

Lung cancer, Sherlock Holmes and piano

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Image of lung cancer

When we think of lung cancer we typically tend to think it’s the end result of years of smoking cigarettes. But, according to the Centers for Disease Control and Prevention, between 10 and 20 percent of cases of lung cancer (20,000 to 40,000 cases a year) happen to non-smokers, people who have either never smoked or smoked fewer than 100 cigarettes in their life. Now researchers have found that there are different genetic types of cancer for smokers and non-smokers, and that might mean the need for different kinds of treatment.

A team at the National Cancer Institute did whole genome sequencing on tumors from 232 never-smokers who had lung cancer. In an interview with STATnews, researcher Maria Teresa Landi said they called their research the Sherlock-Lung study, after the famous fictional pipe-smoking detective Sherlock Holmes. “We used a detective approach. By looking at the genome of the tumor, we use the changes in the tumors as a footprint to follow to infer the causes of the disease.”

They also got quite creative in naming the three different genetic subtypes they found. Instead of giving them the usual dry scientific names, they called them piano, mezzo-forte and forte; musical terms for soft, medium and loud.

Half of the tumors in the non-smokers were in the piano group. These were slow growing with few mutations. The median latency period for these (the time between being exposed to something and being diagnosed) was nine years. The mezzo-forte group made up about one third of the cases. Their cancers were more aggressive with a latency of around 14 weeks. The forte group were the most aggressive, and the ones that most closely resembled smokers’ cancer, with a latency period of just one month.

So, what is the role of stem cells in this research? Well, in the study, published in the journal Nature Genetics the team found that the piano subtype seemed to be connected to genes that help regulate stem cells. That complicates things because it means that the standard treatments for lung cancer that work for the mezzo-forte and forte varieties, won’t work for the piano subtype.

“If this is true, it changes a lot of things in the way we should think of tumorigenesis,” Dr. Landi said.

With that in mind, and because early-detection can often be crucial in treating cancer, what can non-smokers do to find out if they are at risk of developing lung cancer? Well, right now there are no easy answers. For example, the U.S. Preventive Services Task Force does not recommend screening for people who have never smoked because regular CT scans could actually increase an otherwise healthy individual’s risk of developing cancer.

A personal reason to develop a better gene therapy

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Credit : Allison Dougherty, Broad Communications

For Sharif Tabebordbar, finding a gene therapy for genetic muscle wasting diseases was personal. When he was a teenager, his father was diagnosed with a rare genetic muscle disease that eventually left him unable to walk.

In an interview with the Broad Institute at MIT he said: “I watched my dad get worse and worse each day. It was a huge challenge to do things together as a family – genetic disease is a burden on not only patients but families. I thought: This is very unfair to patients and there’s got to be a way to fix this. That’s been my motivation during the 10 years that I’ve been working in the field of gene therapy.”

That commitment now seems to be paying off. In a study published in the journal Cell, Tabebordar and his team at MIT and Harvard showed how they have developed a new, safer and easier way to deliver genes to help repair wasting muscles.   

In earlier treatments targeting genetic muscle diseases, researchers used a virus to help deliver the gene that would correct the problem. However, to be effective they had to use high doses of the gene-carrying virus to ensure it reached as many muscles throughout the body as possible. But this meant that more of the payload often ended up in the liver and that led to severe side effects in some patients, even a few deaths.

The usual delivery method of these gene-correcting therapies is something called an adeno-associated virus (AAV), so Dr. Tabebordar set out to develop a new kind of AAV, one that would be safer for patients and more effective at tackling the muscle wasting.

They started by taking an adeno-associated virus called AAV9 and then set out about tweaking its capsid – that’s the outer shell that helps protect the virus and allows it to attach to another cell and penetrate it to deliver the corrected gene. They called this new viral vector MyoAAV and in tests it quickly showed it had an enhanced ability to deliver genes into cells.

The team showed that it not only was around 10 times more efficient at reaching muscle than other AAVs, but that it also reduces the amount that reaches the liver. This meant that MyoAAV could achieve impressive results in doses up to 250 times lower than those previously used.

In animal studies MyoAAV showed encouraging results in diseases like Duchenne Muscular Dystrophy and X-linked myotubular myopathy. Dr. Amy Wagers, a co-senior author of the study, says they are hopeful it will be equally effective in people.

“All of these results demonstrate the broad applicability of the MyoAAV vectors for delivery to muscle. These vectors work in different disease models and across different ages, strains and species, which demonstrates the robustness of this family of AAVs. We have an enormous amount of information about this class of vectors from which the field can launch many exciting new studies.”

Tiny tools for the smallest of tasks, editing genes

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Developing new tools to edit genes

Having the right tools to do a job is important. Try using a large screwdriver to tighten the screws on your glasses and you quickly appreciate that it’s not just the type of tool that’s important, it’s also the size. The same theory applies to gene editing. And now researchers at Stanford have developed a tool that can take on even the tiniest of jobs.

The tool involves the use of CRISPR. You may well have heard about CRISPR. The magazine New Scientist described it this way: “CRISPR is a technology that can be used to edit genes and, as such, will likely change the world.” For example, CIRM is funding research using CRISPR to help children born with severe combined immunodeficiency, a rare, fatal immune disorder.  

There’s just one problem. Right now, CRISPR is usually twinned with a protein called Cas9. Together they are used to remove unwanted genes and insert a corrected copy of the bad gene. However, that CRISPR-Cas9 combination is often too big to fit into all our cells. That may seem hard to understand for folks like me with a limited science background, but trust the scientists, they aren’t making this stuff up.

To address that problem, Dr. Stanley Qi and his team at Stanford created an even smaller version, one they call CasMINI, to enable them to go where Cas9 can’t go. In an article on Fierce Biotech, Dr. Qi said this mini version has some big benefits: “If people sometimes think of Cas9 as molecular scissors, here we created a Swiss knife containing multiple functions. It is not a big one, but a miniature one that is highly portable for easy use.”

How much smaller is the miniature version compared to the standard Cas9? About half the size, 529 amino acids, compared to Cas9’s 1,368 amino acids.”

The team conclude their study in the journal Molecular Cell saying this could have widespread implications for the field: “This provides a new method to engineer compact and efficient CRISPR-Cas effectors that can be useful for broad genome engineering applications, including gene regulation, gene editing, base editing, epigenome editing, and chromatin imaging.”

Mother and daughter team up to fight bias and discrimination in treatment for people with sickle cell disease

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Adrienne Shapiro and Marissa Cors are a remarkable pair by any definition. The mother and daughter duo share a common bond, and a common goal. And they are determined not to let anyone stop them achieving that goal.

Marissa was born with sickle cell disease (SCD) a life-threatening genetic condition where normally round, smooth red blood cells are instead shaped like sickles. These sickle cells are brittle and can clog up veins and arteries, blocking blood flow, damaging organs, and increasing the risk of strokes. It’s a condition that affects approximately 100,000 Americans, most of them Black.

Adrienne became a patient advocate, founding Axis Advocacy, after watching Marissa get poor treatment in hospital Emergency Rooms.  Marissa often talks about the way she is treated like a drug-seeker simply because she knows what medications she needs to help control excruciating pain on her Sickle Cell Experience Live events on Facebook.

Now the two are determined to ensure that no one else has to endure that kind of treatment. They are both fierce patient advocates, vocal both online and in public. And we recently got a chance to sit down with them for our podcast, Talking ‘Bout (re) Generation. These ladies don’t pull any punches.

Enjoy the podcast.

CIRM is funding four clinical trials aimed at finding new treatments and even a cure for sickle cell disease.