Why people seek out unproven and potentially unsafe stem cell treatments

Every day I field phone calls and emails from people looking for a stem cell therapy to help them cope with everything from arthritis to cancer. Often, they will mention that they saw an ad for a clinic online or in a local newspaper claiming they had stem cell therapies that could help fix anything and asking me if they are legitimate.

Even after I try to explain that the therapies these clinics are offering haven’t been tested in a clinical trial and that there’s scant evidence to show they are even safe let alone effective, I know that a good chunk of the callers are going to try them anyway.

Now a survey by the Mayo Clinic takes a deeper dive into why people are willing to put science aside and open up their wallets to go to predatory stem cell clinics for so-called “therapies”.

Dr. Zubin Master. Photo courtesy Mayo Clinic

In a news release Dr. Zubin Master, a co-author of the study, says many patients are lured in by hype and hope.

“We learned that many patients interested in stem cells had beliefs that are not supported by current medical evidence. For example, many thought stem cells were better than surgery or the standard of care.”

The survey asked 533 people, who had approached the Mayo Clinic’s Regenerative Medicine Therapeutic Suites for a consultation about arthritis or musculoskeletal problems, three questions.

  • Why are you interested in stem cell treatment for your condition?
  • How did you find out about stem cell treatment for your condition?
  • Have you contacted a stem cell clinic?

A whopping 46 percent of those who responded said they thought stem cell therapy would help them avoid or at least delay having to get a hip or knee replacement, or that it was a better option than surgery. Another 26 percent said they thought it would ease the pain of an arthritic joint.

The fact that there is little or no evidence to support any of these beliefs didn’t seem to matter. Most people say they got their information about these “therapies” online or by talking to friends and family.

These “therapies” aren’t cheap either. They can cost thousands, sometimes tens of thousands of dollars, and that comes out of the patient’s pocket because none of this is covered by insurance. Yet every year people turn to these bogus clinics because they don’t like the alternatives, mainly surgery.

There is a lot of promising stem cell research taking place around the US trying to find real scientific solutions to arthritic joints and other problems. The California Institute for Regenerative Medicine (CIRM) has invested almost $24 million in this research. But until those approaches have proven themselves effective and, hopefully, been approved for wider use by the Food and Drug Administration, CIRM and other agencies will have to keep repeating a message many people just don’t want to hear, that these therapies are not yet ready for prime time.

An experimental gene therapy with a hairy twist

In October 2019, 20-year-old Jordan Janz became the first person in the world to receive an experimental therapy for cystinosis. Cystinosis is a rare genetic disorder characterized by the accumulation of an amino acid called cystine in different tissues and organs of the body including the kidneys, eyes, muscles, liver, pancreas, and brain. This accumulation of cystine ultimately leads to multi-organ failure, eventually causing premature death in early adulthood. On average, cystinosis patients live to 28.5 years old. By that calculation, Janz didn’t have a lot of time.

The treatment was grueling but worth it. The experimental gene therapy funded by the California Institute for Regenerative Medicine seemed to work and Janz began to feel better. There was, however, an unexpected change. Janz’s almost white, blonde hair had settled into a darker tone. Of all the things the gene therapy was expected to alter such as the severity of his cystinosis symptoms hair color was not one of them. Eventually, the same phenomenon played out in other people: So far in the gene-therapy trial, four of the five patients all of whom are white have gotten darker hair.

The outcome, while surprising to researchers, didn’t seem to be a sign of something going awry, instead they determined that it might be a very visible sign of the gene therapy working.

The sudden hair-color changes were surprising to Stephanie Cherqui, a stem-cell scientist at UC San Diego and the principal investigator of the gene-therapy trial. However, it didn’t seem to be a sign of something going awry, instead Cherqui and her colleagues determined that it might be a very visible sign of the gene therapy working.

But exactly how did genetically modifying Janz’s (and other participants’) blood cells change his hair color? In this instance, scientists chose to genetically tweak blood stem cells because they have a special ability: Some eventually become white blood cells, which then travel to all different parts of the body.

Janz’s new white blood cells were genetically modified to express the gene that is mutated in cystinosis, called CTNS. Once they traveled to his eyes, skin, and gut, the white blood cells began pumping out the missing protein encoded by the gene. Cells in the area began taking up the protein and clearing away long accumulated cystine crystals. In Janz, the anti-cystine proteins from his modified blood cells must have reached the hair follicles in his skin. There, they cleared out the excess cystine that was blocking normal melanin production, and his hair got darker.

Hair color is one way in which patients in the clinical trial are teaching scientists about the full scope of the CTNS gene. The investigators have since added hair biopsies to the trial in order to track the color changes in a more systematic fashion.

Read the full article on The Atlantic.

Stem Cell Agency Board Invests in 19 Discovery Research Programs Targeting Cancers, Heart Disease and Other Disorders

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Dr. Judy Shizuru, Stanford University

While stem cell and gene therapy research has advanced dramatically in recent years, there are still many unknowns and many questions remaining about how best to use these approaches in developing therapies. That’s why the governing Board of the California Institute for Regenerative Medicine (CIRM) today approved investing almost $25 million in 19 projects in early stage or Discovery research.

The awards are from CIRM’s DISC2 Quest program, which supports  the discovery of promising new stem cell-based and gene therapy technologies that could be translated to enable broad use and ultimately, improve patient care.

“Every therapy that helps save lives or change lives begins with a researcher asking a simple question, “What if?”, says Dr. Maria T. Millan, the President and CEO of CIRM. “Our Quest awards reflect the need to keep supporting early stage research, to gain a deeper understanding of stem cells work and how we can best tap into that potential to advance the field.”

Dr. Judy Shizuru at Stanford University was awarded $1.34 million to develop a safer, less-toxic form of bone marrow or hematopoietic stem cell transplant (HCT). HCT is the only proven cure for many forms of blood disorders that affect people of all ages, sexes, and races worldwide. However, current methods involve the use of chemotherapy or radiation to destroy the patient’s own unhealthy blood stem cells and make room for the new, healthy ones. This approach is toxic and complex and can only be performed by specialized teams in major medical centers, making access particularly difficult for poor and underserved communities.

Dr. Shizuru proposes developing an antibody that can direct the patient’s own immune cells to kill diseased blood stem cells. This would make stem cell transplant safer and more effective for the treatment of many life-threatening blood disorders, and more accessible for people in rural or remote parts of the country.

Lili Yang UCLA Broad Stem Cell Research Center: Photo courtesy Reed Hutchinson PhotoGraphics

Dr. Lili Yang at UCLA was awarded $1.4 million to develop an off-the-shelf cell therapy for ovarian cancer, which causes more deaths than any other cancer of the female reproductive system.

Dr. Yang is using immune system cells, called invariant natural killer T cells (iNKT) to attack cancer cells. However, these iNKT cells are only found in small numbers in the blood so current approaches involve taking those cells from the patient and, in the lab, modifying them to increase their numbers and strength before transplanting them back into the patient. This is both time consuming and expensive, and the patient’s own iNKT cells may have been damaged by the cancer, reducing the likelihood of success.

In this new study Dr. Yang will use healthy donor cord blood cells and, through genetic engineering, turn them into the specific form of iNKT cell therapy targeting ovarian cancer. This DISC2 award will support the development of these cells and do the necessary testing and studies to advance it to the translational stage.

Timothy Hoey and Tenaya Therapeutics Inc. have been awarded $1.2 million to test a gene therapy approach to replace heart cells damaged by a heart attack.

Heart disease is the leading cause of death in the U.S. with the highest incidence among African Americans. It’s caused by damage or death of functional heart muscle cells, usually due to heart attack. Because these heart muscle cells are unable to regenerate the damage is permanent. Dr. Hoey’s team is developing a gene therapy that can be injected into patients and turn their cardiac fibroblasts, cells that can contribute to scar tissue, into functioning heart muscle cells, replacing those damaged by the heart attack.

The full list of DISC2 Quest awards is:

APPLICATION NUMBERTITLE OF PROGRAMPRINCIPAL INVESTIGATORAMOUNT
  DISC2-13400  Targeted Immunotherapy-Based Blood Stem Cell Transplantation    Judy Shizuru, Stanford Universtiy  $1,341,910    
  DISC2-13505  Combating Ovarian Cancer Using Stem Cell-Engineered Off-The-Shelf CAR-iNKT Cells    Lili Yang, UCLA  $1,404,000
  DISC2-13515  A treatment for Rett syndrome using glial-restricted
neural progenitor cells  
  Alysson Muotri, UC San Diego  $1,402,240    
  DISC2-13454  Targeting pancreatic cancer stem cells with DDR1 antibodies.    Michael Karin, UC San Diego  $1,425,600  
  DISC2-13483  Enabling non-genetic activity-driven maturation of iPSC-derived neurons    Alex Savtchenko, Nanotools Bioscience  $675,000
  DISC2-13405  Hematopoietic Stem Cell Gene Therapy for Alpha
Thalassemia  
  Don Kohn, UCLA    $1,323,007  
    DISC2-13507  CAR T cells targeting abnormal N-glycans for the
treatment of refractory/metastatic solid cancers  
  Michael Demetriou, UC Irvine  $1,414,800  
  DISC2-13463  Drug Development of Inhibitors of Inflammation Using
Human iPSC-Derived Microglia (hiMG)  
  Stuart Lipton, Scripps Research Inst.  $1,658,123  
  DISC2-13390  Cardiac Reprogramming Gene Therapy for Post-Myocardial Infarction Heart Failure    Timothy Hoey, Tenaya Therapeutics  $1,215,000  
  DISC2-13417  AAV-dCas9 Epigenetic Editing for CDKL5 Deficiency Disorder    Kyle Fink, UC Davis  $1,429,378  
  DISC2-13415  Defining the Optimal Gene Therapy Approach of
Human Hematopoietic Stem Cells for the Treatment of
Dedicator of Cytokinesis 8 (DOCK8) Deficiency  
  Caroline Kuo, UCLA  $1,386,232  
  DISC2-13498  Bioengineering human stem cell-derived beta cell
organoids to monitor cell health in real time and improve therapeutic outcomes in patients  
  Katy Digovich, Minutia, Inc.  $1,198,550  
  DISC2-13469  Novel antisense therapy to treat genetic forms of
neurodevelopmental disease.  
  Joseph Gleeson, UC San Diego  $1,180,654  
  DISC2-13428  Therapeutics to overcome the differentiation roadblock in Myelodysplastic Syndrome (MDS)    Michael Bollong, Scripps Research Inst.  $1,244,160  
  DISC2-13456  Novel methods to eliminate cancer stem cells    Dinesh Rao, UCLA  $1,384,347  
  DISC2-13441  A new precision medicine based iPSC-derived model to study personalized intestinal fibrosis treatments in
pediatric patients with Crohn’s diseas  
  Robert Barrett Cedars-Sinai  $776,340
  DISC2-13512  Modified RNA-Based Gene Therapy for Cardiac
Regeneration Through Cardiomyocyte Proliferation
  Deepak Srivastava, Gladstone Institutes  $1,565,784
  DISC2-13510  An hematopoietic stem-cell-based approach to treat HIV employing CAR-T cells and anti-HIV broadly
neutralizing antibodies  
  Brian Lawson, The Scintillon Institute  $1,143,600  
  DISC2-13475  Developing gene therapy for dominant optic atrophy using human pluripotent stem cell-derived retinal organoid disease model    Xian-Jie Yang, UCLA  $1,345,691  

Can regenerative medicine turn back the clock on aging?

One of my favorite phrases is “standing room only”. I got a chance to use it last week when we held a panel discussion on whether regenerative medicine could turn back the clock on aging. The event was at the annual conference of the International Society for Stem Cell Research (ISSCR) and more than 150 people packed into a conference room to hear the debate (so far more than 800 also watched a live stream of the event.)

It’s not surprising the place was jammed. The speakers included:

  • Dr. Deepak Srivastava, the President of the Gladstone Institutes, an expert on heart disease and the former President of ISSCR.
  • Dr. Stanley “Tom” Carmichael, Chair of the Department of Neurology at UCLA and an expert on strokes and other forms of brain injury.
  • Adrienne Shapiro, the mother of a daughter with sickle cell disease, a tireless patient advocate and supporter of regenerative medicine research, and the co-founder of Axis Advocacy, a family support organization for people with sickle cell.
  • Jonathan Tomas, PhD, JD, the Chair of the CIRM Board.

And the topic is a timely one. It is estimated that as many as 90 percent of the people who die every day, die from diseases of aging such as heart disease, stroke, and cancer. So, what can be done to change that, to not just slow down or stop these diseases, but to turn back the clock, to repair the damage already done and replace cells and tissues already destroyed.

The conversation was enlightening, hopeful and encouraging, but also cautionary.

You can watch the whole event on our Youtube channel.

I think you are going to enjoy it.

Two reasons to remember June 19th

Today marks two significant events for the Black community. June 19th is celebrated as Juneteenth, the day when federal troops arrived in Galveston, Texas to ensure that the enslaved people there were free. That moment came two and a half years after President Abraham Lincoln signed the Emancipation Proclamation into law.

June 19th is also marked as World Sickle Cell Awareness Day. It’s an opportunity to raise awareness about a disease that affects around 100,000 Americans, most of them Black, and the impact it has on the whole family and entire communities.

Sickle cell disease (SCD) is an inherited blood disorder that is caused by a genetic mutation. Instead of red blood cells being smooth and round and flowing easily through arteries and veins, the cells are sickle shaped and brittle. They can clog up arteries and veins, cutting off blood to vital organs, causing intense pain, organ damage and leading to premature death.

SCD can be cured with a bone marrow transplant, but that’s a risky procedure and most people with SCD don’t have a good match. Medications can help keep it under control but cannot cure it. People with SCD live, on average, 30 years less than a healthy adult.

CIRM has invested almost $60 million in 13 different projects, including five clinical trials, to try and develop a cure for SCD. There are encouraging signs of progress. For example, in July of 2020, Evie Junior took part in a CIRM-funded clinical trial where his own blood stem cells were removed then, in the laboratory, were genetically modified to repair the genetic mutation that causes the disease. Those cells were returned to him, and the hope is they’ll create a sickle cell-free blood supply. Evie hasn’t had any crippling bouts of pain or had to go to the hospital since his treatment.

Evie Junior: Photo by Jaquell Chandler

CIRM has also entered into a unique partnership with the National Heart, Lung and Blood Institute (NHLBI) to co-fund cell and gene therapy programs under the NIH “Cure Sickle Cell” initiative.  The goal is to markedly accelerate the development of cell and gene therapies for SCD.

“There is a real need for a new approach to treating SCD and making life easier for people with SCD and their families,” says Adrienne Shapiro, the mother of a daughter with SCD and the co-founder of Axis Advocacy, a sickle cell advocacy and education organization. “Finding a cure for Sickle Cell would mean that people like my daughter would no longer have to live their life in short spurts, constantly having their hopes and dreams derailed by ER visits and hospital stays.  It would mean they get a chance to live a long life, a healthy life, a normal life.”

We will all keep working together to advance this research and develop a cure. Until then Juneteenth will be a reminder of the work that still lies ahead.

Replacement brain cells offer hope for Parkinson’s treatment

A colony of iPSCs from a Parkinson’s patient (left) and dopaminergic neurons made from these iPSCs (right) to model PD. (Image credit: Jeanne Loring)

A new study that used adult blood stem cells to create replacement brain nerve cells appears to help rats with Parkinson’s.

In Parkinson’s, the disease attacks brain nerve cells that produce a chemical called dopamine. The lack of dopamine produces a variety of symptoms including physical tremors, depression, anxiety, insomnia and memory problems. There is no cure and while there are some effective treatments they tend to wear off over time.

In this study, researchers at Arizona State University took blood cells from humans and, using the iPSC method, changed those into dopamine-producing neurons. They then cultured those cells in the lab before implanting them in the brains of rats which had Parkinson’s-like symptoms.

They found that rats given cells that had been cultured in the lab for 17 days survived in greater numbers and seemed to be better at growing new connections in their brains, compared to rats given cells that had been cultured for 24 or 37 days.

In addition, those rats given larger doses of the cells experienced a complete reversal of their symptoms, compared to rats given smaller doses.

In a news release, study co-author Dr. Jeffrey Kordower, said: “We cannot be more excited by the opportunity to help individuals who suffer from [a] genetic form of Parkinson’s disease, but the lessons learned from this trial will also directly impact patients who suffer from sporadic, or non-genetic forms of this disease.”

The study, published in the journal npj Regenerative Medicine, says this approach might also help people suffering from other neurological diseases like Alzheimer’s or Huntington’s disease.

UCLA-led team creates first comprehensive map of human blood stem cell development

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Human blood stem cells emerging from specialized endothelial cells in the wall of an embryonic aorta. UCLA scientists’ confirmation of this process clarifies a longstanding controversy about the stem cells’ cellular origin. Image Credit: Hanna Mikkola Lab/UCLA, Katja Schenke-Layland Lab/University of Tübingen, Nature

California researchers from UCLA and colleagues have created a first-of-its-kind roadmap that traces each step in the development of blood stem cells in the human embryo, providing scientists with a blueprint for producing fully functional blood stem cells in the lab. 

The research, published in the journal Nature, could help expand treatment options for blood cancers like leukemia and inherited blood disorders such as sickle cell disease, said UCLA’s Dr. Hanna Mikkola, who led the study. 

The California Institute for Regenerative Medicine (CIRM) has funded and supported Mikkola’s earlier blood stem cell research through various grants

Overcoming Limitations 

Blood stem cells, also called hematopoietic stem cells, can make unlimited copies of themselves and differentiate into every type of blood cell in the human body. For decades, doctors have used blood stem cells from the bone marrow of donors and the umbilical cords of newborns in life-saving transplant treatments for blood and immune diseases.  

However, these treatments are limited by a shortage of matched donors and hampered by the low number of stem cells in cord blood. 

Researchers have long sought to create blood stem cells in the lab from human pluripotent stem cells, which can potentially give rise to any cell type in the body. But success has been elusive, in part because scientists have lacked the instructions to make lab-grown cells become self-renewing blood stem cells rather than short-lived blood progenitor cells, which can only produce limited blood cell types. 

“Nobody has succeeded in making functional blood stem cells from human pluripotent stem cells because we didn’t know enough about the cell we were trying to generate,” said Mikkola. 

A New Roadmap

The new roadmap will help researchers understand the fundamental differences between the two cell types, which is critical for creating cells that are suitable for use in transplantation therapies, said UCLA scientist Vincenzo Calvanese, a co–first author of the research, along with UCLA’s Sandra Capellera-Garcia and Feiyang Ma. 

Researchers Vincenzo Calvanese and Hanna Mikkola. | Credit: Eddy Marcos Panos (left); Reed Hutchinson/UCLA

“We now have a manual of how hematopoietic stem cells are made in the embryo and how they acquire the unique properties that make them useful for patients,” said Calvanese, who is also a group leader at University College London.  

The research team created the resource using new technologies that enable scientists to identify the unique genetic networks and functions of thousands of individual cells and to reveal the location of these cells in the embryo. 

The data make it possible to follow blood stem cells as they emerge and migrate through various locations during their development, starting from the aorta and ultimately arriving in the bone marrow. Importantly, the map unveils specific milestones in their maturation process, including their arrival in the liver, where they acquire the special abilities of blood stem cells. 

The research group also pinpointed the exact precursor in the blood vessel wall that gives rise to blood stem cells. This discovery clarifies a longstanding controversy about the stem cells’ cellular origin and the environment that is needed to make a blood stem cell rather than a blood progenitor cell. 

Through these insights into the different phases of human blood stem cell development, scientists can see how close they are to making a transplantable blood stem cell in the lab. 

A Better Understanding of Blood Cancers

In addition, the map can help scientists understand how blood-forming cells that develop in the embryo contribute to human disease. For example, it provides the foundation for studying why some blood cancers that begin in utero are more aggressive than those that occur after birth. 

“Now that we’ve created an online resource that scientists around the world can use to guide their research, the real work is starting,” Mikkola said. “It’s a really exciting time to be in the field because we’re finally going to be seeing the fruits of our labor.” 

Read the full release here

How a health tech company is using virtual reality to treat stem cell patients 

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Photo: Jessica Lewis

Virtual reality may soon be used to treat cancer patients who are recovering from stem cell procedures.  

Healthcare technology company Rocket VR Health—in partnership with Massachusetts General Hospital—is developing a virtual reality (VR) therapy that intends to enhance the quality of life of cancer patients who receive stem cell transplants.  

Specifically, the therapy is intended to help with distress management in blood cancer patients undergoing blood stem cell transplantation (HCT) in an in-clinic setting. HCT (short for hematopoietic cell transplantation) can be used to treat certain types of cancer, such as leukemia, myeloma, and lymphoma, and other blood and immune system diseases that affect the bone marrow. 

The average hospital length of stay for patients with hematologic malignancies—cancers that start in blood forming tissues such as bone marrow—who undergo HCT is typically 28 days. During the hospitalization period, patients can’t leave their rooms as their immune system is weakened while their bone marrow is re-generated.  

As contact with the outside world is limited during recovery, patients may endure significant short-term and long-term distress that affects their physical and psychological well-being. 

The treatment being developed consists of psychoeducation, therapy, and relaxation exercises in a VR environment designed to be self-administered by patients. The immersive environment aims to give patients access to the outside world virtually while being confined to their hospital room. 

It is reported that patients who receive integrated psychological interventions during their hospital stays have fewer depression and PTSD symptoms than those who receive standard transplant care alone. 

Rocket VR Health hopes to create a therapy that hospitals and health systems can offer to patients using clinically validated therapies over fully-immersive virtual reality to make psychosocial care more accessible and effective. 

CIRM-Funded Study Helping Babies Battle a Deadly Immune Disorder Gets Boost from FDA

Hataalii Begay, age 4, first child treated with UCSF gene therapy for Artemis-SCID

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When Hataalii Begay was born in a remote part of the Navajo nation he was diagnosed with a rare, usually fatal condition. Today, thanks to a therapy developed at UCSF and funded by CIRM, he’s a normal healthy four year old boy running around in cowboy boots.

That stem cell therapy could now help save the lives of other children born with this deadly immune disorder because it has been granted fast-track review status by the US Food and Drug Administration (FDA).

The California Institute for Regenerative Medicine (CIRM) has invested $12 million to test this therapy in a clinical trial at UC San Francisco.

The disorder is Artemis-SCID, a form of severe combined immunodeficiency disease. Children born with this condition have no functioning immune system so even a simple infection can prove life-threatening or fatal.

Currently, the only approved treatment for Artemis-SCID is a bone-marrow transplant, but many children are unable to find a healthy matched donor for that procedure. Even when they do find a donor they often need regular injections of immunoglobulin to boost their immune system.

In this clinical trial, UCSF Doctors Mort Cowan and Jennifer Puck are using the patient’s own blood stem cells, taken from their bone marrow. In the lab, the cells are modified to correct the genetic mutation that causes Artemis-SCID and then re-infused back into the patients. The goal is that over the course of several months these cells will create a new blood supply, one that is free of Artemis-SCID, and that will in turn help repair the child’s immune system.

So far the team has treated ten newly-diagnosed infants and three older children who failed transplants. Dr. Cowan says early data from the trial is encouraging. “With gene therapy, we are seeing these babies getting older. They have normal T-cell immunity and are getting immunized and vaccinated. You wouldn’t know they had any sort of condition if you met them; it’s very heartening.”

Because of that encouraging data, the FDA is granting this approach Regenerative Medicine Advanced Therapy (RMAT) designation. RMAT is a fast-track designation that can help speed up the development, review and potential approval of treatments for serious or life-threatening diseases.

“This is great news for the team at UCSF and in particular for the children and families affected by Artemis-SCID,” says Dr. Maria T. Millan, the President and CEO of CIRM. “The RMAT designation means that innovative forms of cell and gene therapies like this one may be able to accelerate their route to full approval by the FDA and be available to all the patients who need it.”

Stem cell discovery could help shorten cancer treatment recovery 

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A researcher prepares to study blood cells under a microscope. Photo by Getty.

A recent discovery by stem cell scientists at Cedars-Sinai may help make cancer treatment more efficient and shorten the time it takes for people to recover from radiation and chemotherapy.  

Published in the journal Nature Communications, the study by Dr. John Chute and his team (and co-funded by CIRM) revealed a mechanism through which the blood vessels in the bone marrow respond to injury, such as from chemotherapy or radiation. 

Each year, about 650,000 cancer patients receive chemotherapy in an outpatient oncology clinic in the United States.  

When people receive radiation or chemotherapy as part of their cancer treatment, their blood counts plummet. It typically takes several weeks for these counts to return to normal levels. During this period patients are at risk for developing infections that may lead to hospitalization, disruptions in chemotherapy schedules, and even death. 

Chute and his colleagues found that when mice receive radiation treatment, the cells that line the inner walls of the blood vessels in the bone marrow produce a protein called semaphorin 3A. This protein tells another protein, called neuropilin 1, to kill damaged blood vessels in the bone marrow. 

When the investigators blocked the ability of these blood vessel cells to produce neuropilin 1 or semaphorin 3A, or injected an antibody that blocks semaphorin 3A communication with neuropilin 1, the veins and arteries in the bone marrow regenerated faster following irradiation. In addition, blood counts increased dramatically after one week. 

“We’ve discovered a mechanism that appears to control how blood vessels regenerate following injury,” said Chute, senior author of the paper. “Inhibiting this mechanism causes rapid recovery of the blood vessels and blood cells in bone marrow following chemotherapy or irradiation.”  

In principle, Chute said, targeting this mechanism could allow patients to recover following chemotherapy in one to two weeks, instead of three or four weeks as currently experienced. 

Christina M. Termini, a post-doctoral scientist at the David Geffen School of Medicine at UCLA, was the first author of this study. Read the source press release here.