Persistence pays off in search for clue to heart defects

A team of scientists led by Benoit Bruneau (left), including Irfan Kathiriya (center) and Kavitha Rao (right), make inroads into understanding what genes are improperly deployed in some cases of congenital heart disease.  Photo courtesy Gladstone Institute

For more than 20 years Dr. Benoit Bruneau has been trying to identify the causes of congenital heart disease, the most common form of birth defect in the U.S. It turns out that it’s not one cause, but many.

Congenital heart disease covers a broad range of defects, some relatively minor and others life-threatening and even fatal. It’s been known that a mutation in a gene called TBX5 is responsible for some of these defects, so, in a CIRM-funded study ($1.56 million), Bruneau zeroed in on this mutation to see if it could help provide some answers.

In the past Bruneau, the director of the Gladstone Institute of Cardiovascular Disease, had worked with a mouse model of TBX5, but this time he used human induced pluripotent stem cells (iPSCs). These are cells that can be manipulated in the lab to become any kind of cell in the human body. In a news release Bruneau says this was an important step forward.

“This is really the first time we’ve been able to study this genetic mutation in a human context. The mouse heart is a good proxy for the human heart, but it’s not exactly the same, so it’s important to be able to carry out these experiments in human cells.”

The team took some iPSCs, changed them into heart cells, and used a gene editing tool called CRISPR-Cas9 to create the kinds of mutations in TBX5 that are seen in people with congenital heart disease. What they found was some genes were affected a lot, some not so much. Which is what you might expect in a condition that causes so many different forms of problems.

“It makes sense that some are more affected than others, but this is the first experimental data in human cells to show that diversity,” says Bruneau.

But they didn’t stop there. Oh no. Then they did a deep dive analysis to understand how the different ways that different cells were impacted related to each other. They found some cells were directly affected by the TBX5 mutation but others were indirectly affected.

The study doesn’t point to a simple way of treating congenital heart disease but Bruneau says it does give us a much better understanding of what’s going wrong, and perhaps will give us better ideas on how to stop that.

“Our new data reveal that the genes are really all part of one network—complex but singular—which needs to stay balanced during heart development. That means if we can figure out a balancing factor that keeps this network functioning, we might be able to help prevent congenital heart defects.”

The study is published in the journal Developmental Cell.

You can’t take it if you don’t make it

Biomedical specialist Mamadou Dialio at work in the Cedars-Sinai Biomanufacturing Center. Photo by Cedars-Sinai.

Following the race to develop a vaccine for COVID-19 has been a crash course in learning how complicated creating a new therapy is. It’s not just the science involved, but the logistics. Coming up with a vaccine that is both safe and effective is difficult enough, but then how do you make enough doses of it to treat hundreds of millions of people around the world?

That’s a familiar problem for stem cell researchers. As they develop their products they are often able to make enough cells in their own labs. But as they move into clinical trials where they are testing those cells in more and more people, they need to find a new way to make more cells. And, of course, they need to plan ahead, hoping the therapy is approved by the Food and Drug Administration, so they will need to be able to manufacture enough doses to meet the increased demand.

We saw proof of that planning ahead this week with the news that Cedars-Sinai Medical Center in Los Angeles has opened up a new Biomanufacturing Center.

Dr. Clive Svendsen, executive director of the Cedars-Sinai Board of Governors Regenerative Medicine Institute, said in a news release, the Center will manufacture the next generation of drugs and regenerative medicine therapies.

“The Cedars-Sinai Biomanufacturing Center leverages our world-class stem-cell expertise, which already serves scores of clients, to provide a much-needed biomanufacturing facility in Southern California. It is revolutionary by virtue of elevating regenerative medicine and its therapeutic possibilities to an entirely new level-repairing the human body.”

This is no ordinary manufacturing plant. The Center features nine “clean rooms” that are kept free from dust and other contaminants. Everyone working there has to wear protective suits and masks to ensure they don’t bring anything into the clean rooms.

The Center will specialize in manufacturing induced pluripotent stem cells, or iPSCs. Dhruv Sareen, PhD, executive director of the Biolmanufacturing Center, says iPSCs are cells that can be turned into any other kind of cell in the body.

“IPSCs are powerful tools for understanding human disease and developing therapies. These cells enable us to truly practice precision medicine by developing drug treatments tailored to the individual patient or groups of patients with similar genetic profiles.”

The Biomanufacturing Center is designed to address a critical bottleneck in bringing cell- and gene-based therapies to the clinic. After all, developing a therapy is great, but it’s only half the job. Making enough of it to help the people who need it is the other half.

CIRM is funding Dr. Svendsen’s work in developing therapies for ALS and other diseases and disorders.  

Precision guided therapy from a patient’s own cells

Dr. Wesley McKeithan, Stanford

Imagine having a tool you could use to quickly test lots of different drugs against a disease to see which one works best. That’s been a goal of stem cell researchers for many years but turning that idea into a reality hasn’t been easy. That may be about to change.

A team of CIRM-funded researchers at the Stanford Cardiovascular Institute and the Human BioMolecular Research Institute in San Diego found a way to use stem cells from patients with a life-threatening heart disease, to refine an existing therapy to make it more effective, with fewer side effects.

The disease in question is called long QT syndrome (LQTS). This is a heart rhythm condition that can cause fast, chaotic heartbeats. Some people with the condition have seizures. In some severe cases, particularly in younger people, LQTS can cause sudden death.

There are a number of medications that can help keep LQTS under control. One of these is mexiletine. It’s effective at stabilizing the heart’s rhythm, but it also comes with some side effects such as stomach pain, chest discomfort, drowsiness, headache, and nausea.

The team wanted to find a way to test different forms of that medication to see if they could find one that worked better and was safer to take. So they used induced pluripotent stem cells (iPSCs) from patients with LQTS to do just that.

iPSCs are cells that are made from human tissue – usually skin – that can then be turned into any other cell in the body. In this case, they took tissue from people with LQTS and then turned them into heart cells called cardiomyocytes, the kind affected by the disease. The beauty of this technique is that even though these cells came from another source, they now look and act like cardiomyocytes affected by LQTS.

Dr. Mark Mercola, Stanford

In a news release Stanford’s Dr. Mark Mercola, the senior author of the study, said using these kinds of cells gave them a powerful tool.

“Drugs for heart disease are typically developed using overly simplified models, like tumor cells engineered in a specific way to mimic a biochemical event. Consequently, drugs like this one, mexiletine, have undesirable properties of concern in treating patients. Here, we used cells from a patient to generate that person’s heart muscle cells in a dish so we could visualize both the good and bad effects of the drug.”

The researchers then used these man-made cardiomyocytes to test various drugs that were very similar in structure to mexiletine. They were looking for ones that could help stabilize the heart arrhythmia but didn’t produce the unpleasant side effects. And they found some promising candidates.

Study first author, Dr. Wesley McKeithan, says the bigger impact of the study is that they were able to show how this kind of cell from patients with a particular disease can be used to “guide drug development and identify better drug improvement and optimization in a large-scale manner.”

 “Our approach shows the feasibility of introducing human disease models early in the drug development pipeline and opens the door for precision drug design to improve therapies for patients.”

The study is published in the journal Cell Stem Cell.

Therapy developed with CIRM award used in new clinical trial for COVID-19

Dr. Joshua Rhein, Assistant Professor of Medicine in the University of Minnesota Medical School’s Division of Infectious Diseases and International Medicine
Image Credit: University of Minnesota

While doctors are still trying to better understand how to treat some of the most severe cases of COVID-19, researchers are looking at their current scientific “toolkit” to see if any potential therapies for other diseases could also help treat patients with COVID-19. One example of this is a treatment developed by Fate Therapeutics called FT516, which received support in its early stages from a Late Stage Preclinical grant awarded by CIRM.

FT516 uses induced pluripotent stem cells (iPSCs), which are a kind of stem cell made from reprogrammed skin or blood cells. These newly made stem cells have the potential to become any kind of cell in the body. For FT516, iPSCs are transformed into natural killer (NK) cells, which are a type of white blood cell that are a vital part of the immune system and play a role in fighting off viral infections.

Prior to the coronavirus pandemic, FT516 was used in a clinical trial to treat patients with acute myeloid leukemia (AML) and B-cell lymphoma, which are two different kinds of blood cancer.

Due to the natural ability of NK cells to fight off viruses, it is believed that FT516 may also help play a role in diminishing viral replication of the novel coronavirus in COVID-19 patients. In fact, Fate Therapeutics, in partnership with the University of Minnesota, has treated their first COVID-19 patient with FT516 in a new clinical trial.

In a news release, Dr. Joshua Rhein, Physician at the University of Minnesota running the trial site, elaborates on how FT516 could help COVID-19 patients.

“The medical research community has been mobilized to meet the unique challenges that COVID-19 presents. There are limited treatment options for COVID-19, and we have been inundated daily with reports of varying quality describing the potential of numerous therapies. We know that NK cells play an important role in responding to SARS-CoV-2, the virus responsible for COVID-19, and that these cells often become depleted in infected patients. Our intent is to replenish NK cells in order to restore a functional immune system and directly target the virus.”

In its own response to the coronavirus pandemic, CIRM has funded three clinical trials as part of $5 million in emergency funding for COVID-19 related projects. They include the following: a convalescent plasma study conducted by Dr. John Zaia at City of Hope, a treatment for acute respiratory distress syndrome (a serious and lethal consequence of COVID-19) conducted by Dr. Michael Matthay at UCSF, and a study that also uses NK cells to treat COVID-19 patients conducted by Dr. Xiaokui Zhang at Celularity Inc.  Visit our dashboard page to learn more about these clinical projects.

Stem cells used to promote quick and precise bone healing

A close-up view of the intricate microarchitecture of the pluripotent stem-cell-derived extracellular matrix. Image Credit: Carl Gregory/Texas A&M

Although some broken bones can be mended with the help of a cast, others require more complex treatments. Bone grafts, which can come from the patient’s own body or a donor, are used to transplant bone tissue to the injury site. However, these procedures can have setbacks such as increased recovery time and chronic pain. Each year approximately 600,000 people in the United States alone experience complications from bone healing.

Researchers at Texas A&M University found a way to use induced pluripotent stem cells (iPSCs), a type of stem cell that can turn into any cell type and can be derived from adults cells (e.g. skin cells), to create superior bone grafts. The team of researchers said these grafts could potentially be used to promote swift and precise bone healing, enabling patients to optimally benefit from surgical intervention.

The Texas A&M team used iPSCS to make mesenchymal stem cells (MSCs), which make the extracellular matrix needed for bone grafts. MSCs can be obtained from bone marrow, but they have a relatively shorter life span and are not as biologically active when compared to MSCs generated from iPSCs.

To test the effectiveness of their iPSC generated bone grafts, they implanted the extracellular matrix at a site of bone defects. After a few weeks, they found that their iPSC generated matrix was five to sixfold more effective than the best FDA-approved graft stimulator.

In a news release from Texas A&M, Dr. Roland Kaunas discusses the potential benefits of using iPSC generated bone grafts.

“Our material is very promising because the pluripotent stem cells can ideally generate many batches of the extracellular matrix from just a single donor which will greatly simplify the large-scale manufacturing of these bone grafts.”

Additionally, the Texas A&M team said this approach has the potential to be incorporated into numerous engineered implants, such as 3D-printed implants or metal screws, so that these parts integrate better with the surrounding bone.

The full results of this study were published in Nature Communications.

A brief video on bone grafts from Texas A&M is available below.

Super charging killer cells to fight leukemia

Colorized scanning electron micrograph of a natural killer cell.
Photo credit: National Institute of Allergy and Infectious Diseases

Racing car drivers are forever tinkering with their cars, trying to streamline them and soup up their engines because while fast is good, faster is better. Researchers do the same things with potential anti-cancer therapies, tinkering with them to make them safer and more readily available to patients while also boosting their ability to fight cancer.

That’s what researchers at the University of California San Diego (UCSD), in a CIRM-funded study, have done. They’ve taken immune system cells – with the already impressive name of ‘natural killer’ (NK) cells – and made them even deadlier to cancers.

These natural killer (NK) cells are considered one of our immune system’s frontline weapons against outside threats to our health, things like viruses and cancer. But sometimes the cancers manage to evade the NKs and spread throughout the body or, in the case of leukemia, throughout the blood.

Lots of researchers are looking at ways of taking a patient’s own NK cells and, in the lab boosting their ability to fight these cancers. However, using a patient’s own cells is both time consuming and very, very expensive.

Dan Kaufman MD

Dr. Dan Kaufman and his team at UCSD decided it would be better to try and develop an off-the-shelf approach, a therapy that could be mass produced from a single batch of NK cells and made available to anyone in need.

Using the iPSC method (which turns tissues like skin or blood into embryonic stem cell-like cells, capable of becoming any other cell in the body) they created a line of NK cells. Then they removed a gene called CISH which slows down the activities of cytokines, acting as a kind of brake or restraint on the immune system.

In a news release, Dr. Kaufman says removing CISH had a dramatic effect, boosting the power of the NK cells.

“We found that CISH-deleted iPSC-derived NK cells were able to effectively cure mice that harbor human leukemia cells, whereas mice treated with the unmodified NK cells died from the leukemia.”

Dr. Kaufman says the next step is to try and develop this approach for testing in people, to see if it can help people whose disease is not responding to conventional therapies.

“Importantly, iPSCs provide a stable platform for gene modification and since NK cells can be used as allogeneic cells (cells that come from donors) that do not need to be matched to individual patients, we can create a line of appropriately modified iPSC-derived NK cells suitable for treating hundreds or thousands of patients as a standardized, ‘off-the-shelf’ therapy.”

The study is published in the journal Cell Stem Cell.

You can bank on CIRM

Way back in 2013, the CIRM Board invested $32 million in a project to create an iPSC Bank. The goal was simple;  to collect tissue samples from people who have different diseases, turn those samples into high quality stem cell lines – the kind known as induced pluripotent stem cells (iPSC) – and create a facility where those lines can be stored and distributed to researchers who need them.

Fast forward almost seven years and that idea has now become the largest public iPSC bank in the world. The story of how that happened is the subject of a great article (by CIRM’s Dr. Stephen Lin) in the journal Science Direct.

Dr. Stephen Lin

In 2013 there was a real need for the bank. Scientists around the world were doing important research but many were creating the cells they used for that research in different ways. That made it hard to compare one study to another and come up with any kind of consistent finding. The iPSC Bank was designed to change that by creating one source for high quality cells, collected, processed and stored under a single, consistent method.

Tissue samples – either blood or skin – were collected from thousands of individuals around California. Each donor underwent a thorough consent process – including being shown a detailed brochure – to explain what iPS cells are and how the research would be done.

The diseases to be studied through this bank include:

  • Age-Related Macular Degeneration (AMD)
  • Alzheimer’s disease
  • Autism Spectrum Disorder (ASD)
  • Cardiomyopathies (heart conditions)
  • Cerebral Palsy
  • Diabetic Retinopathy
  • Epilepsy
  • Fatty Liver diseases
  • Hepatitis C (HCV)
  • Intellectual Disabilities
  • Primary Open Angle Glaucoma
  • Pulmonary Fibrosis

The samples were screened to make sure they were safe – for example the blood was tested for HBV and HIV – and then underwent rigorous quality control testing to make sure they met the highest standards.

Once approved the samples were then turned into iPSCs at a special facility at the Buck Institute in Novato and those lines were then made available to researchers around the world, both for-profit and non-profit entities.

Scientists are now able to use these cells for a wide variety of uses including disease modeling, drug discovery, drug development, and transplant studies in animal research models. It gives them a greater ability to study how a disease develops and progresses and to help discover and test new drugs or other therapies

The Bank, which is now run by FUJIFILM Cellular Dynamics, has become a powerful resource for studying genetic variation between individuals, helping scientists understand how disease and treatment vary in a diverse population. Both CIRM and Fuji Film are committed to making even more improvements and additions to the collection in the future to ensure this is a vital resource for researchers for years to come.

What to be thankful for this Thanksgiving: scientists hard at work

Biomedical technician Louis Pinedo feeds stem cells their special diet. Photo by Cedars-Sinai.

With Thanksgiving and Black Friday approaching in the next couple of days, we wanted to give thanks to all the scientists hard at work during this holiday weekend. Science does not sleep–the groundbreaking research and experiments that are being conducted do not take days off. There are tasks in the laboratory that need to be done daily otherwise months, even years, of important work can be lost in an instant.

Below is a story from Cedars-Sinai Medical Center that talks about one of these scientists, Louis Pinedo, that will be working during this holiday weekend.

Stem Cells Don’t Take the Day Off on Thanksgiving

Inside a Cedars-Sinai Laboratory, Where a Scientist Will be Busy Feeding Stem Cells During the Holiday

While most of us are stuffing ourselves with turkey and pumpkin pie at home on Thanksgiving Day, the staff at one Cedars-Sinai laboratory will be on the job, feeding stem cells.

“Stem cells do not observe national holidays,” says Loren Ornelas-Menendez, the manager of a lab that converts samples of adult skin and blood cells into stem cells—the amazing “factories” our bodies use to make our cells. These special cells help medical scientists learn how diseases develop and how they might be cured.

Stem cells are living creatures that must be hand-fed a special formula each day, monitored for defects and maintained at just the right temperature. And that means the cell lab is staffed every day, 52 weeks a year.

These cells are so needy that Ornelas-Menendez jokes: “Many people have dogs. We have stem cells.”

Millions of living stem cells are stored in the David and Janet Polak Foundation Stem Cell Core Laboratory at the Cedars-Sinai Board of Governors Regenerative Medicine Institute. Derived from hundreds of healthy donors and patients, they represent a catalogue of human ills, including diabetes, breast cancer, Alzheimer’s disease, Parkinson’s disease and Crohn’s disease.

Cedars-Sinai scientists rely on stem cells for many tasks: to make important discoveries about how our brains develop; to grow tiny versions of human tissues for research; and to create experimental treatments for blindness and neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS) that they are testing in clinical trials.

The lab’s main collection consists of induced pluripotent stem cells, or iPSCs, which mimic the all-powerful stem cells we all had as embryos. These ingenious cells, which Cedars-Sinai scientists genetically engineer from adult cells, can make any type of cell in the body—each one matching the DNA of the donor. Other types of stem cells in the lab make only one or two kinds of cells, such as brain or intestinal cells.

Handy and versatile as they are, stem cells are high-maintenance. A few types, such as those that make connective tissue cells for wound healing, can be fed as infrequently as every few days. But iPSCs require a daily meal to stay alive, plus daily culling to weed out cells that have started to turn into cells of the gut, brain, breast or other unwanted tissues.

So each day, lab staff suit up and remove trays of stem cells from incubators that are set at a cozy 98.6 degrees. Peering through microscopes, they carefully remove the “bad” cells to ensure the purity of the iPSCs they will provide to researchers at Cedars-Sinai and around the world.

While the cells get sorted, a special feeding formula is defrosting in a dozen bottles spread around a lab bench. The formula incudes sodium, glucose, vitamins and proteins. Using pipettes, employees squeeze the liquid into food wells inside little compartments that contain the iPSCs. Afterward, they return the cells to their incubators.

The lab’s 10 employees are on a rotating schedule that ensures the lab is staffed on weekends and holidays, not just weekdays. On Thanksgiving Day this year, biomedical technician Louis Pinedo expects to make a 100-mile round trip from his home in Oxnard, California, to spend several hours at work, filling nearly 600 feeding wells. On both Christmas and New Year’s Day, two employees are expected to staff the lab.

All this ceaseless effort helps make Cedars-Sinai one of the world’s top providers of iPSCs, renowned for consistency and quality. Among the lab’s many clients are major universities and the global Answer ALS project, which is using the cells in its search for a cure for this devastating disease.

That’s why the lab’s director, Dhruv Sareen, PhD, suggests that before you sit down to your Thanksgiving feast, why not lift a glass to these hard-working lab employees?

“One day the cells they tend could lead to treatments for diseases that have plagued humankind for centuries,” he says. “And that’s something to be truly thankful for.”

Blood-brain barrier chip created with stem cells expands potential for personalized medicine

An Organ-Chip used in the study to create a blood-brain barrier (BBB).

The brain is a complex part of the human body that allows for the formation of thoughts and consciousness. In many ways it is the essence of who we are as individuals. Because of its importance, our bodies have developed various layers of protection around this vital organ, one of which is called the blood-brain barrier (BBB).

The BBB is a thin border of various cell types around the brain that regulate what can enter the brain tissue through the bloodstream. Its primary purpose is to prevent toxins and other unwanted substances from entering the brain and damaging it. Unfortunately this barrier can also prevent helpful medications, designed to fix problems, from reaching the brain.

Several brain disorders, such as Amyotrophic Lateral Sclerosis (ALS – also known as Lou Gehrig’s disease), Parkinson’s Disease (PD), and Huntington’s Disease (HD) have been linked to defective BBBs that keep out critical biomolecules needed for healthy brain activity.

In a CIRM-funded study, a team at Cedars-Sinai Medical Center created a BBB through the use of stem cells and an Organ-Chip made from induced pluripotent stem cells (iPSCs). These are a specific type of stem cells that can turn into any type of cell in the body and can be generated from a person’s own cells. In this study, iPSCs were created from adult blood samples and used to make the neurons and other supporting cells that make up the BBB. These cells were then placed inside an Organ-Chip which recreates the environment that cells normally experience within the human body.

Inside the 3-D Organ-Chip, the cells were able to form a BBB that functions as it does in the body, with the ability to block entry of certain drugs. Most notably, when the BBB was generated from cell samples of patients with HD, the BBB malfunctioned in the same way that it does in patients with the disease.

These findings expand the potential for personalized medicine for various brain disorders linked to problems in the BBB. In a press release, Dr. Clive Svendsen, director of the Cedars-Sinai Board of Governors Regenerative Medicine Institute and senior author of the study, was quoted as saying,

“The study’s findings open a promising pathway for precision medicine. The possibility of using a patient-specific, multicellular model of a blood barrier on a chip represents a new standard for developing predictive, personalized medicine.”

The full results of the study were published in the scientific journal Cell Stem Cell.

First patient treated for colon cancer using reprogrammed adult cells

Dr. Sandip Patel (left) and Dr. Dan Kaufman (center) of UC San Diego School of Medicine enjoy a light-hearted moment before Derek Ruff (right) receives the first treatment for cancer using human-induced pluripotent stem cells (hiPSCs). Photo courtesy of UC San Diego Health.

For patients battling cancer for the first time, it can be quite a draining and grueling process. Many treatments are successful and patients go into remission. However, there are instances where the cancer returns in a much more aggressive form. Unfortunately, this was the case for Derek Ruff.

After being in remission for ten years, Derek’s cancer returned as Stage IV colon cancer, meaning that the cancer has spread from the colon to distant organs and tissues. According to statistics from Fight Colorectal Cancer, colorectal cancer is the 2nd leading cause of cancer death among men and women combined in the United States. 1 in 20 people will be diagnosed with colorectal cancer in their lifetime and it is estimated that there will be 140,250 new cases in 2019 alone. Fortunately, Derek was able to enroll in a groundbreaking clinical trial to combat his cancer.

In February 2019, as part of a clinical trial at the Moores Cancer Center at UC San Diego Health in collaboration with Fate Therapeutics, Derek became the first patient in the world to be treated for cancer with human-induced pluripotent stem cells (hiPSCs). hiPSCs are human adult cells, such as those found on the skin, that are reprogrammed into stem cells with the ability to turn into virtually any kind of cell. In this trial, hiPSCs were reprogrammed into natural killer (NK) cells, which are specialized immune cells that are very effective at killing cancer cells, and are aimed at treating Derek’s colon cancer.

A video clip from ABC 10 News San Diego features an interview with Derek and the groundbreaking work being done.

In a public release, Dr. Dan Kaufman, one of the lead investigators of this trial at UC San Diego School of Medicine, was quoted as saying,

“This is a landmark accomplishment for the field of stem cell-based medicine and cancer immunotherapy. This clinical trial represents the first use of cells produced from human induced pluripotent stem cells to better treat and fight cancer.”

In the past, CIRM has given Dr. Kaufman funding related to the development of NK cells. One was a $1.9 million grant for developing a different type of NK cell from hiPSCs, which could also potentially treat patients with lethal cancers. The second grant was a $4.7 million grant for developing NK cells from human embryonic stem cells (hESCs) to potentially treat patients with acute myelogenous leukemia (AML).

In the public release, Dr. Kaufman is also quoted as saying,

“This is a culmination of 15 years of work. My lab was the first to produce natural killer cells from human pluripotent stem cells. Together with Fate Therapeutics, we’ve been able to show in preclinical research that this new strategy to produce pluripotent stem cell-derived natural killer cells can effectively kill cancer cells in cell culture and in mouse models.”