California has the largest aging population in the United States. The U.S. Census Bureau has estimated that one in five Californians will be 65 or older by the year 2030. Unfortunately with age comes a wide of health related issues that can arise such as Alzheimer’s.
Alzheimer’s is caused by changes in the brain that affect memory and thinking skills. The disease can progress to the point where carrying out the simplest tasks become quite a challenge. In the United States alone, 5.8 million people are living with Alzheimer’s, 630,000 of whom live in California. By 2050, the number of people with Alzheimer’s in the United States is expected to increase to almost 14 million.
To address this growing problem, California Governor Gavin Newsom announced the creation of a California Alzheimer’s Task Force comprised of scientists, politicians, and other individuals dedicated to addressing the needs of the Alzheimer’s community and the impact the disease has on California. The new task force has been tasked with releasing a report on the disease and ways to address the challenges it poses by 2020.
One of these task force members is our very own Lauren Miller Rogen, who is a dedicated member of our governing Board and the co-founder of Hilarity for Charity, a charity organization that raises awareness about and funds for research into Alzheimer’s. In addition to her advocacy work, Lauren is also a screenwriter and actress, staring alongside her husband Seth Rogen in movies such as 50/50 and Superbad.
“I’m so honored to join the Task Force to fight for the 670,000 Californians currently living with Alzheimer’s and for those who care for them,” Miller Rogen said. “This is a tremendous and diverse group who intend to create and propose real ideas to change the course of this disease.”
For Lauren, her journey towards becoming an advocate for Alzheimer’s is a very personal one. Her grandfather died of Alzheimer’s when she was just 12 years old and her grandmother died of the disease six years after that. Now, her mother is struggling with Alzheimer’s, having been diagnosed at the age of 55.
All this week we have been highlighting blogs from our SPARK (Summer Program to Accelerate Regenerative medicine Knowledge) students. SPARK gives high school students a chance to spend their summer working in a world class stem cell research facility here in California. In return they write about their experiences and what they learned.
The standard for blogs this year was higher than ever, so choosing a winner was particularly tough. In the end we chose Abigail Mora, who interned at UC San Francisco. We felt the obstacles she overcame in getting to this point made her story all the more remarkable and engaging.
When I was 15, my mother got sick and went to several doctors. Eventually, she found out that she was pregnant with a 3-month-old baby. A month after, my mom fell from the stairs, which were not high but still dangerous. Luckily, everything seemed to be okay with the baby. In the last week of her six-month pregnancy, she went in the clinic for a regular check-up but she ended up giving birth to my brother, who was born prematurely. She stayed in the clinic for a month and my brother also had to stay so that his lungs could develop properly.
When he came home, I was so happy. I spent a lot of time with him and was like his second mom. After an initial period of hard time, he grew into a healthy kid. Then I moved to San Francisco with my aunt, leaving my parents and siblings in Mexico so that I could become a better English speaker and learn more about science. My experience with my brother motivated me to learn more about the condition of premature babies, since there are many premature babies who are not as fortunate. I want to study neurodevelopment in premature kids, and how it may go wrong.
I was so
happy when I got into the SEP High School Program, which my chemistry teacher
introduced me to, and I found the research of Eric Huang’s lab at UCSF about
premature babies and stem cell development in the brain super interesting. I met
Lakisha and Jean, and they introduced me to the lab and helped me walk through
the training process.
My internship experience was outstanding: I enjoyed doing research and how my mentor Jiapei helped me learn new things about the brain. I learned that there are many different cell types in the brain, like microglia, progenitor cells, and intermediate progenitors.
As all things in life can be challenging, I was able to persevere with my mentor’s help. For example, when I first learned how to cut mouse brains using a cryostat, I found it hard to pick up the tissue onto slides. After practicing many times, I became more familiar with the technique and my slices got better. Another time, I was doing immunostaining and all the slices fell from the slide because we didn’t bake the slides long enough. I was sad, but we learned from our mistakes and there are a lot of trials and errors in science.
I’ve also learned that in science, since we are studying the unknown, there is not a right or wrong answer. We use our best judgement to draw conclusions from what we observe, and we repeat the experiment if it’s not working.
The most challenging part of this internship was learning and understanding all the new words in neuroscience. Sometimes, I got confused with the abbreviations of these words. I hope in the future I can explain as well as my mentor Jiapei explained to me.
My parents are away from me but they support me, and they think that this internship will open doors to better opportunities and help me grow as a person.
I want to become a researcher because I want to help lowering the risk of neurodevelopmental disorders in premature babies. Many of these disorders, such as autism or schizophrenia, don’t have cures. These are some of the hardest diseases to cure because people aren’t informed about them and not enough research has been done. Hopefully, one day I can work on developing a cure for these disorders.
Way back in the 1990’s scientists were hard at work decoding the human genome, trying to map and understand all the genes that make up people. At the time there was a sense of hope, a feeling that once we had decoded the genome, we’d have cures for all sorts of things by next Thursday. It didn’t quite turn out that way.
The same was true
for stem cell research. In the early days there was a strong feeling that this
was going to quite quickly produce new treatments and cures for diseases
ranging from Parkinson’s and Alzheimer’s to heart disease and stroke. Although
we have made tremendous strides we are still not where we hoped we’d be.
It’s a tough lesson
to learn, but an important one: good scientific research moves at its own pace
and pays little heed to our hopes or desires. It takes time, often a long time,
and money, usually a lot of money, to develop new treatments for deadly
diseases and disorders.
Many people, particularly those battling deadly diseases who are running out of time, are frustrated at the slow pace of stem cell research, at the years and years of work that it takes to get even the most promising therapy into a clinical trial where it can be tested in people. That’s understandable. If your life is on the line, it’s difficult to be told that you have to be patient. Time is a luxury many patients don’t have.
But that caution is
necessary. The last thing we want to do is rush to test something in people
that isn’t ready. And stem cells are a whole new way of treating disease, using
cells that may stay in the body for years, so we really need to be sure we have
done everything we can to ensure they are safe before delivering them to
The field of gene
therapy was set back years after one young patient, Jesse Gelsinger,
died as a result of an early experimental treatment. We don’t want the same to
happen to stem cell research.
And yet progress is
being made, albeit not as quickly as any of us would like. At the end of the
first ten years of CIRM’s existence we had ten projects that we supported that
were either in, or applying to be in, a clinical trial sanctioned by the US
Food and Drug Administration (FDA). Five years later that number is 56.
Most of those are in
Phase 1 or 2 clinical trials which means they are still trying to show they are
both safe and effective enough to be made available to a wider group of people.
However, some of our projects are in Phase 3, the last step before, hopefully,
being given FDA approval to be made more widely available and – just as
important – to be covered by insurance.
Other CIRM-funded projects
have been given Regenerative Medicine Advanced Therapy (RMAT)
designation by the FDA, a
new program that allows projects that show they are safe and benefit patients
in early stage clinical trials, to apply for priority review, meaning they
could get approved faster than normal. Out of 40 RMAT designations awarded so
far, six are for CIRM projects.
We are working hard
to live up to our mission statement of accelerating stem cell treatments to
patients with unmet medical needs. We have been fortunate in having $3 billion
to spend on advancing this research in California; an amount no other US state,
indeed few other countries, have been able to match. Yet even that amount is
tiny compared to the impact that many of these diseases have. For example, the
economic cost of treating diabetes in the US is a staggering $327 billion a
The simple truth is
that unless we, as a nation, invest much more in scientific research, we are
not going to be able to develop cures and new, more effective, treatments for a
wide range of diseases.
Time and money are
always going to be challenging when it comes to advancing stem cell research
and bringing treatments to patients. With greater knowledge and understanding
of stem cells and how best to use them we can speed up the timeline. But
without money none of that can happen.
Chemotherapy and radiation are two of the front-line weapons in treating cancer. They can be effective, even life-saving, but they can also be brutal, taking a toll on the body that lasts for months. Now a team at UCLA has developed a therapy that might enable the body to bounce back faster after chemo and radiation, and even make treatments like bone marrow transplants easier on patients.
First a little
background. Some cancer treatments use chemotherapy and radiation to kill the
cancer, but they can also damage other cells, including those in the bone
marrow responsible for making blood stem cells. Those cells eventually recover
but it can take weeks or months, and during that time the patient may feel
fatigue and be more susceptible to infections and other problems.
In a CIRM-supported study, UCLA’s Dr. John Chute and his team developed a drug that speeds up the process of regenerating a new blood supply. The research is published in the journal Nature Communications.
They focused their
attention on a protein called PTP-sigma that is found in blood stem cells and
acts as a kind of brake on the regeneration of those cells. Previous studies by
Dr. Chute showed that, after undergoing radiation, mice that have less
PTP-sigma were able to regenerate their blood stem cells faster than mice that
had normal levels of the protein.
So they set out to
identify something that could help reduce levels of PTP-sigma without affecting
other cells. They first identified an organic compound with the charming name
of 6545075 (Chembridge) that was reported to be effective against PTP-sigma.
Then they searched a library of 80,000 different small molecules to find
something similar to 6545075 (and this is why science takes so long).
From that group they
developed more than 100 different drug candidates to see which, if any, were
effective against PTP-sigma. Finally, they found a promising candidate, called DJ009.
In laboratory tests DJ009 proved itself effective in blocking PTP-sigma in
human blood stem cells.
They then tested
DJ009 in mice that were given high doses of radiation. In a news
release Dr. Chute said the results were very encouraging:
“The potency of this compound in animal models was very
high. It accelerated the recovery of blood stem cells, white blood cells and
other components of the blood system necessary for survival. If found to be
safe in humans, it could lessen infections and allow people to be discharged
from the hospital earlier.”
Of the radiated mice, most that were given DJ009
survived. In comparison, those that didn’t get DJ009 died within three weeks.
They saw similar benefits in mice given chemotherapy.
Mice with DJ009 saw their white blood cells – key components of the immune
system – return to normal within two weeks. The untreated mice had dangerously
low levels of those cells at the same point.
It’s encouraging work and the team are already getting
ready for more research so they can validate their findings and hopefully take
the next step towards testing this in people in clinical trials.
Glioblastoma is an aggressive form of cancer that invades brain tissue, making it extremely difficult to treat. Current therapies involving radiation and chemotherapy are effective in destroying the bulk of brain cancer cells, but they are not able to reach the brain cancer stem cells, which have the ability to grow and multiply indefinitely. These cancer stem cells enable the glioblastoma to continuously grow even after treatment, which leads to recurring tumor formation.
Dr. Jeremy Rich and his team at UC San Diego examined glioblastomas further by obtaining glioblastoma tumor samples donated by patients that underwent surgery and implanting these into mice. Dr. Rich and his team tested a combinational treatment that included a targeted cancer therapy alongside a drug named teriflunomide, which is used to treatment patients with multiple sclerosis. The research team found that this approach successfully halted the growth of glioblastoma stem cells, shrank the tumor size, and improved survival in the mice.
In order to continue replicating, glioblastoma stem cells make pyrimidine, one of the compounds that make up DNA. Dr. Rich and his team noticed that higher rates of pyrimidine were associated with poor survival rates in glioblastoma patients. Teriflunomide works by blocking an enzyme that is necessary to make pyrmidine, therefore inhibiting glioblastoma stem cell replication.
In a press release, Dr. Rich talks about the potential these findings hold by stating that,
“We’re excited about these results, especially because we’re talking about a drug that’s already known to be safe in humans.”
However, he comments on the need to evaluate this approach further by saying that,
“This laboratory model isn’t perfect — yes it uses human patient samples, yet it still lacks the context a glioblastoma would have in the human body, such as interaction with the immune system, which we know plays an important role in determining tumor growth and survival. Before this drug could become available to patients with glioblastoma, human clinical trials would be necessary to support its safety and efficacy.”
The full results to this study were published in Science Translational Medicine.
There is nothing you can do to prevent or reduce your risk of leukemia. That’s not a very reassuring statement considering that this year alone almost 62,000 Americans will be diagnosed with leukemia; almost 23,000 will die from the disease. That’s why CIRM is funding four clinical trials targeting leukemia, hoping to develop new approaches to treat, and even cure it.
also why our next special Facebook Live “Ask the Stem Cell Team” event is
focused on this issue. Join us on Thursday, August 29th from
1pm to 2pm PDT to hear a discussion about the progress in, and promise of,
stem cell research for leukemia.
two great panelists joining us:
Dr. Crystal Mackall, has many titles including serving as the Founding Director of the Stanford Center for Cancer Cell Therapy. She is using an innovative approach called a Chimeric Antigen Receptor (CAR) T Cell Therapy. This works by isolating a patient’s own T cells (a type of immune cell) and then genetically engineering them to recognize a protein on the surface of cancer cells, triggering their destruction. This is now being tested in a clinical trial funded by CIRM.
Natasha Fooman. To describe Natasha as a patient advocate would not do justice to her experience and expertise in fighting blood cancer and advocating on behalf of those battling the disease. For her work she has twice been named “Woman of the Year” by the Leukemia and Lymphoma Society. In 2011 she was diagnosed with a form of lymphoma that was affecting her brain. Over the years, she would battle lymphoma three times and undergo chemotherapy, radiation and eventually a bone marrow transplant. Today she is cancer free and is a key part of a CIRM team fighting blood cancer.
We hope you’ll join
us to learn about the progress being made using stem cells to combat blood
cancers, the challenges ahead but also the promising signs that we are
advancing the field.
We also hope you’ll take an active role by posting questions on Facebook during the event, or sending us questions ahead of time to email@example.com. We will do our best to address as many as we can.
link to the event, feel free to share this with anyone you think might be interested
in joining us for Facebook Live “Ask the Stem Cell Team about Leukemia”
In ancient Greek mythology, a Chimera was a creature that was usually depicted as a lion with an additional goat head and a serpent for a tail. Due to the Chimera’s animal hybrid nature, the term “chimeric” came to fruition in the scientific community as a way to describe an organism containing two or more different sets of DNA.
A CIRM-funded study conducted by Dr. Mathew Blurton-Jones and his team at UC Irvine describes a way for human brain immune cells, known as microglia, to grow and function inside mice. Since the mice contain a both human cells and their own mice cells, they are described as being chimeric.
In order to develop this chimeric “mighty mouse” model, Dr. Blurton-Jones and his team generated induced pluripotent stem cells (iPSCs), which have the ability to turn into any kind of cell, from cell samples donated by adult patients. For this study, the researchers converted iPSCs into microglia, a type of immune cell found in the brain, and implanted them into genetically modified mice. After a few months, they found that the implanted cells successfully integrated inside the brains of the mice.
By finding a way to look at human microglia grow and function in real time in an animal model, scientists can further analyze crucial mechanisms contributing to neurological conditions such as Alzheimer’s, Parkinson’s, traumatic brain injury, and stroke.
For this particular study, Dr. Blurton-Jones and his team looked at human microglia in the mouse brain in relation to Alzheimer’s, which could hold clues to better understand and treat the disease. The team did this by introducing amyloid plaques, protein fragments in the brain that accumulate in people with Alzheimer’s, and evaluating how the human microglia responded. They found that the human microglia migrated toward the amyloid plaques and surrounding them, which is what is observed in Alzheimer’s patients.
In a press release, Dr. Blurton-Jones expressed the importance of studying microglia by stating that,
“Microglia are now seen as having a crucial role in the development and progression of Alzheimer’s. The functions of our cells are influenced by which genes are turned on or off. Recent research has identified over 40 different genes with links to Alzheimer’s and the majority of these are switched on in microglia. However, so far we’ve only been able to study human microglia at the end stage of Alzheimer’s in post-mortem tissues or in petri dishes.”
Furthermore, Dr. Blurton-Jones highlighted the importance of looking at human microglia in particular by saying that,
“The human microglia also showed significant genetic differences from the rodent version in their response to the plaques, demonstrating how important it is to study the human form of these cell.”
The full results of this study were published in Cell.
Getting a breast cancer diagnosis is devastating news in and of itself. Currently, there are treatment options that target three different types of receptors, which are named hormone epidermal growth factor receptor 2 (HER-2), estrogen receptors (ER), and progesterone receptors (PR), commonly found in breast cancer cells, . Unfortunately, in triple-negative breast cancer, which occurs in 10-20% of breast cancer cases, all three receptors are absent, making this form of breast cancer very aggressive and difficult to treat.
In recent years, researchers have discovered that proteins on the cell surface can tell macrophages, an immune cell designed to detect and engulf foreign or abnormal cells, not to eat and destroy them. This can be useful to help normal cells keep the immune system from attacking them, but cancer cells can also use these “don’t eat me” signals to hide from the immune system.
In fact, because of this concept, a CIRM-funded clinical trial is being conducted that uses an antibody called 5F9 to block a “don’t eat me” signal known as CD47 that is found in cancer cells. The results of this trial, which have been announced in a previous blog post, are very promising.
Further building on this concept, a CIRM-funded study has now discovered a potential new target for triple-negative breast cancer as well as ovarian cancer. Dr. Irv Weissman and a team of researchers at Stanford University have discovered an additional “don’t eat me” signal called CD24 that cancers seem to use to evade detection and destruction by the immune system.
In a press release, Dr. Weissman talks about his work with CD47 and states that,
“Finding that not all patients responded to anti-CD47 antibodies helped fuel our research at Stanford to test whether non-responder cells and patients might have alternative ‘don’t eat me’ signals.”
The scientists began by looking for signals that were produced more highly in cancers than in the tissues from which the cancers arose. It is here that they discovered CD24 and then proceeded to implant human breast cancer cells in mice for testing. When the CD24 signaling was blocked, the mice’s immune system attacked the cancer cells.
An important discovery was that ovarian and triple-negative breast cancer were highly affected by blocking of CD24 signaling. The other interesting discovery was that the effectiveness of CD24 blockage seems to be complementary to CD47 blockage. In other words, some cancers, like blood cancers, seem to be highly susceptible to blocking CD47, but not to CD24 blockage. For other cancers, like ovarian cancer, the opposite is true. This could suggest that most cancers will be susceptible to the immune system by blocking the CD24 or CD47 signal, and that cancers may be even more vulnerable when more than one “don’t eat me” signal is blocked.
Dr. Weissman and his team are now hopeful that potential therapies to block CD24 signaling will follow in the footsteps of the clinical trials related to CD47.
CIRM’s mission is very simple: to accelerate stem cell treatments to patients with unmet medical needs. Anne Klein’s son, Everett, was a poster boy for that statement. Born with a fatal immune disorder Everett faced a bleak future. But Anne and husband Brian were not about to give up. The following story is one Anne wrote for Parents magazine. It’s testament to the power of stem cells to save lives, but even more importantly to the power of love and the determination of a family to save their son.
My Son Was Born With ‘Bubble Boy’ Disease—But A Gene Therapy Trial Saved His Life
I wish more than anything that my son Everett had not been born with severe combined immunodeficiency (SCID). But I know he is actually one of the lucky unlucky ones. By Anne Klein
As a child in the ’80s, I watched a news story about David Vetter. David was known as “the boy in the bubble” because he was born with severe combined immunodeficiency (SCID), a rare genetic disease that leaves babies with very little or no immune system. To protect him, David lived his entire life in a plastic bubble that kept him separated from a world filled with germs and illnesses that would have taken his life—likely before his first birthday.
I was struck by David’s story. It was heartbreaking and seemed so otherworldly. What would it be like to spend your childhood in an isolation chamber with family, doctors, reporters, and the world looking in on you? I found it devastating that an experimental bone marrow transplant didn’t end up saving his life; instead it led to fatal complications. His mother, Carol Ann Demaret, touched his bare hand for the first and last time when he was 12 years old.
I couldn’t have known that almost 30 years later, my own son, Everett, would be born with SCID too.
Everett’s SCID diagnosis
At birth, Everett was big, beautiful, and looked perfectly healthy. My husband Brian and I already had a 2-and-a-half-year-old son, Alden, so we were less anxious as parents when we brought Everett home. I didn’t run errands with Alden until he was at least a month old, but Everett was out and about with us within a few days of being born. After all, we thought we knew what to expect.
But two weeks after Everett’s birth, a doctor called to discuss Everett’s newborn screening test results. I listened in disbelief as he explained that Everett’s blood sample indicated he may have an immune deficiency.
“He may need a bone marrow transplant,” the doctor told me.
I was shocked. Everett’s checkup with his pediatrician just two days earlier went swimmingly. I hung up and held on to the doctor’s assurance that there was a 40 percent chance Everett’s test result was a false positive.
After five grueling days of waiting for additional test results and answers, I received the call: Everett had virtually no immune system. He needed to be quickly admitted to UCSF Benioff Children’s Hospital in California so they could keep him isolated and prepare to give him a stem cell transplant. UCSF diagnosed him specifically with SCID-X1, the same form David battled.
Beginning SCID treatment
The hospital was 90 miles and more than two hours away from home. Our family of four had to be split into two, with me staying in the hospital primarily with Everett and Brian and Alden remaining at home, except for short visits. The sudden upheaval left Alden confused, shaken, and sad. Brian and I quickly transformed into helicopter parents, neurotically focused on every imaginable contact with germs, even the mildest of which could be life-threatening to Everett.
When he was 7 weeks old, Everett received a stem cell transplant with me as his donor, but the transplant failed because my immune cells began attacking his body. Over his short life, Everett has also spent more than six months collectively in the hospital and more than three years in semi-isolation at home. He’s endured countless biopsies, ultrasounds, CT scans, infusions, blood draws, trips to the emergency department, and medical transports via ambulance or helicopter.
Gene therapy to treat SCID
At age 2, his liver almost failed and a case of pneumonia required breathing support with sedation. That’s when a doctor came into the pediatric intensive care unit and said, “When Everett gets through this, we need to do something else for him.” He recommended a gene therapy clinical trial at the National Institutes of Health (NIH) that was finally showing success in patients over age 2 whose transplants had failed. This was the first group of SCID-X1 patients to receive gene therapy using a lentiviral vector combined with a light dose of chemotherapy.
After the complications from our son’s initial stem cell transplant, Brian and I didn’t want to do another stem cell transplant using donor cells. My donor cells were at war with his body and cells from another donor could do the same. Also, the odds of Everett having a suitable donor on the bone marrow registry were extremely small since he didn’t have one as a newborn. At the NIH, he would receive a transplant with his own, perfectly matched, gene-corrected cells. They would be right at home.
Other treatment options would likely only partially restore his immunity and require him to receive infusions of donor antibodies for life, as was the case with his first transplant. Prior gene therapy trials produced similarly incomplete results and several participants developed leukemia. The NIH trial was the first one showing promise in fully restoring immunity, without a risk of cancer. Brian and I felt it was Everett’s best option. Without hesitation, we flew across the country for his treatment. Everett received the gene therapy in September 2016 when he was 3, becoming the youngest patient NIH’s clinical trial has treated.
It’s been more than two years since Everett received gene therapy and now more than ever, he has the best hope of developing a fully functioning immune system. He just received his first vaccine to test his ability to mount a response. Now 6 years old, he’s completed kindergarten and has been to Disney World. He plays in the dirt and loves shows and movies from the ’80s (maybe some of the same ones David enjoyed).
Everett knows he has been through a lot and that his doctors “fixed his DNA,” but he’s focused largely on other things. He’s vocal when confronted with medical pain or trauma, but seems to block out the experiences shortly afterwards. It’s sad for Brian and me that Everett developed these coping skills at such a young age, but we’re so grateful he is otherwise expressive and enjoys engaging with others. Once in the middle of the night, he woke us up as he stood in the hallway, exclaiming, “I’m going back to bed, but I just want you to know that I love you with all my heart!”
I wish more than anything that Everett had not been born with such a terrible disease and I could erase all the trauma, isolation, and pain. But I know that he is actually one of the lucky unlucky ones. Everett is fortunate his disease was caught early by SCID newborn screening, which became available in California not long before his birth. Without this test, we would not have known he had SCID until he became dangerously ill. His prognosis would have been much worse, even under the care of his truly brilliant and remarkable doctors, some of whom cared for David decades earlier.
When Everett was 4, soon after the gene therapy gave him the immunity he desperately needed, our family was fortunate enough to cross paths with David’s mom, Carol Ann, at an Immune Deficiency Foundation event. Throughout my life, I had seen her in pictures and on television with David. In person, she was warm, gracious, and humble. When I introduced her to Everett and explained that he had SCID just like David, she looked at Everett with loving eyes and asked if she could touch him. As she touched Everett’s shoulder and they locked eyes, Brian and I looked on with profound gratitude.
Anne Klein is a parent, scientist, and a patient advocate for two gene therapy trials funded by the California Institute for Regenerative Medicine. She is passionate about helping parents of children with SCID navigate treatment options for their child.
The invention of GPS navigation systems has made finding your way around so much easier, providing simple instructions on how to get from point A to point B. Now, a new study shows that our bodies have their own internal navigation system that helps stem cells know where to go, and when, in order to build a human heart. And the study also shows what can go wrong when even a few cells fail to follow directions.
In this CIRM-supported study, a team of researchers at the Gladstone Institutes in San Francisco, used a new technique called single cell RNA sequencing to study what happens in a developing heart. Single cell RNA sequencing basically takes a snapshot photo of all the gene activity in a single cell at one precise moment. Using this the researchers were able to follow the activity of tens of thousands of cells as a human heart was being formed.
“This sequencing technique allowed us
to see all the different types of cells present at various stages of heart development
and helped us identify which genes are activated and suppressed along the way. We
were not only able to uncover the existence of unknown cell types, but we also
gained a better understanding of the function and behavior of individual
cells—information we could never access before.”
Then they partnered with a team at Luxembourg Centre for Systems
Biomedicine (LCSB) of the University of Luxembourg which ran a
computational analysis to identify which genes were involved in creating
different cell types. This highlighted one specific gene, called Hand2, that controls
the activity of thousands of other genes. They found that a lack of Hand2 in
mice led to an inability to form one of the heart’s chambers, which in turn led
to impaired blood flow to the lungs. The embryo was creating the cells needed
to form the chamber, but not a critical pathway that would allow those cells to
get where they were needed when they were needed.
Gifford says this has given us a deeper insight into how
cells are formed, knowledge we didn’t have before.
“Single-cell technologies can inform us about how organs
form in ways we couldn’t understand before and can provide the underlying cause
of disease associated with genetic variations. We revealed subtle differences
in very, very small subsets of cells that actually have catastrophic
consequences and could easily have been overlooked in the past. This is the
first step toward devising new therapies.”
These therapies are needed to help treat congenital heart
defects, which are the most common and deadly birth defects. There are more
than 2.5 million Americans with these defects. Deepak Srivastava, President of
Gladstone and the leader of the study, said the knowledge gained in this study
could help developed strategies to help address that.
to see the long-term consequences in adults, and right now, we don’t really
have any way to treat them. My hope is that if we can understand the genetic
causes and the cell types affected, we could potentially intervene soon after
birth to prevent the worsening of their state over time.