Moving one step closer to a therapy for type 1 diabetes

When I was a medical journalist one word I always shied away from was “breakthrough”. There are few true breakthroughs in medicine. Usually any advance is the result of years and years of work. That’s why good science takes time; it takes hundreds of small steps to make a giant leap forward.

Today we took one of those steps. ViaCyte, a company we have supported for many years, just announced that the first patient has been successfully implanted with a device designed to help treat type 1 diabetes.

It’s an important milestone for the company, for us, and of course for people with type 1 diabetes. As Dr. Paul Laikind, the President and CEO of ViaCyte, said in a news release, this is an exciting moment:

“To our knowledge, this is the first time that an embryonic stem cell-derived cell replacement therapy for diabetes has been studied in human subjects, and it represents the culmination of a decade of effort by the ViaCyte team, our collaborators, and our supporters at the California Institute for Regenerative Medicine and at JDRF.”

The VC-01 device is being tested in a clinical trial at the University of California, San Diego Health System. There are two goals; first to see if it is safe; and secondly to see if it helps patients who have type 1 diabetes. When the device is implanted under the skin the cells inside are able to sense when blood sugar is high and, in response, secrete insulin to restore it to a healthy level.

The beauty of the VC-01 is that while it lets cells secrete insulin out, it prevents the body’s own immune system from getting in and attacking the cells.

The device is about the length and thickness of a credit card but only half as wide which makes it easy to implant under the skin.

Today’s news, that this is now truly out of the lab and being tested in patients is an important step in a long road to showing that it works in patients. The people at ViaCyte, who have been working hard on this project for many years, know that they still have a long way to go but for today at least, this step probably feels a little bit more like a skip for joy.

From Stem Cells to Stomachs: Scientists Generate 3D, Functioning Human Stomach Tissue

The human stomach can be a delicate organ. For example, even the healthiest stomach can be compromised by H. pylori bacteria—a tiny but ruthless pathogen which has shown to be linked to both peptic ulcer disease and stomach cancer.

The best way to study how an H. pylori infection leads to conditions like cancer would be to recreate that exact environment, right down to the stomach itself, in the lab. But that task has proven far more difficult than originally imagined.

Part of a miniature stomach grown in the lab, stained to reveal various cells found in normal human stomachs [Credit: Kyle McCracken]

Part of a miniature stomach grown in the lab, stained to reveal various cells found in normal human stomachs [Credit: Kyle McCracken]

But now, scientists at the Cincinnati Children’s Hospital Medical Center and the University of Cincinnati College of Medicine have successfully grown functional, human stomach tissue in a dish—the first time such a feat has been accomplished.

Further, they were then able to test how human stomach tissue reacts to an invasion by H. pylori—a huge leap forward toward one day developing treatments for potentially deadly stomach disease.

Reporting in today’s issue of the journal Nature, senior author Jim Wells describes his team’s method of turning human pluripotent stem cells into stomach cells, known as gastric cells. Wells explained the importance of their breakthrough in a news release:

“Until this study, no one had generated gastric cells from human pluripotent stem cells. In addition, we discovered how to promote formation of three-dimensional gastric tissue with complex architecture and cellular composition.”

The team called this stomach tissue gastric organoids, a kind of ‘mini-stomach’ that mimicked the major cellular processes of a normal, functioning human stomach. Developing a human model of stomach development—and stomach disease—has long been a goal among scientists and clinicians, as animal models of the stomach did not accurately reflect what would be happening in a human stomach.

In this study, the research team identified the precise series of steps that can turn stem cells into gastric cells. And then they set these steps in motion.

Over the course of a month, the team coaxed the formation of gastric organoids that measured less than 1/10th of one inch in diameter. But even with this small size, the team could view the cellular processes that drive stomach formation—and discover precisely what happens when that process goes awry.

But what most intrigued the researchers, which also included first author University of Cincinnati’s Kyle McCracken, was how quickly an H. pylori infection impacted the health of the stomach tissue.

“Within 24 hours, the bacteria had triggered biochemical changes in the organ,” said McCracken.

According to McCracken, as the H. pylori infection spread from cell to cell, the researchers also recorded the activation of c-Met, a gene known to be linked to stomach cancer—further elucidating the relationship between H. pylori and this form of stomach disease.

Somewhat surprisingly, little was known about how gastric cells play a role in obesity-related diseases, such as type 2 diabetes. But thanks to Wells, McCracken and the entire Cincinnati Children’s research team—we are that much closer to shedding light on this process.

Wells also credits his team’s reliance on years of preliminary data performed in research labs around the world with helping them reach this landmark:

“This milestone would not have been possible if it hadn’t been for previous studies from many other basic researchers on understanding embryonic organ development.”

Scientists Develop Stem Cell ‘Special Forces’ in order to Target, Destroy Brain Tumors

Curing someone of cancer is, in theory, a piece of cake: all you have to do is kill the cancer cells while leaving the healthy cells intact.

But in practice, this solution is far more difficult. In fact, it remains one of the great unsolved problems in modern oncology: how do you find, target and destroy each individual cancer cell in the body—while minimizing damage to the surrounding cells.

Encapsulated toxin-producing stem cells (in blue) help kill brain tumor cells in the tumor resection cavity (in green). [Credit: Khalid Shah, MS, PhD]

Encapsulated toxin-producing stem cells (in blue) help kill brain tumor cells in the tumor resection cavity (in green). [Credit: Khalid Shah, MS, PhD]

But luckily, Harvard Stem Cell Institute scientists at Massachusetts General Hospital may have finally struck gold: they have designed special, toxin-secreting stem cells that can target and destroy brain tumors. Their findings, which were performed in laboratory mice and which appear in the latest issue of the journal STEM CELLS, offer up an entirely unique method for eradicating deadly cancers.

Harvard Neuroscientist Khalid Shah, who led the study, explained in last Friday’s news release that the idea of engineering stem cells to kill cancer cells is not new—but there was a key difference in scientists’ ability to target individual cells vs. difficult-to-reach tumors, which is often the case with brain cancer:

“Cancer-killing toxins have been used with great success in a variety of blood cancers, but they don’t work as well in solid tumors because the cancers aren’t as accessible and the toxins have a short half-life.”

The solution, Shah and his team argued, was stem cells. Previously, Shah and his team discovered that stem cells could be used to circumvent these problems. The fact that stem cells continuously renew meant that they could also be used to continually deliver toxins to brain tumors.

“But first, we needed to genetically engineer stem cells that could resist being killed themselves by the toxins,” said Shah.

In this study, the research team introduced a small genetic change, or mutation, into the stem cells so that they become impervious to the toxin’s harmful effects. They then introduced a second mutation that allowed the stem cells to maintain and produce and secrete toxins throughout the cells’ lifetime—effectively giving it an unlimited supply of ammunition to use once it encountered the brain tumor.

They then employed a common technique whereby the toxins were tagged so that they only sought out and infected cancer cells—leaving healthy cells unscathed.

“We tested these stem cells in a clinically relevant mouse model of brain cancer,” Shah described. “After doing all of the molecular analysis and imaging to track the inhibition of protein synthesis within brain tumors, we do see the toxins kill the cancer cells and eventually prolonging the survival in animal models.”

While preliminary, these results are encouraging. As the team continues to refine their method of development and delivery, they are optimistic that they can bring their methods to clinical trial within the next five years.

Stem Cell Stories that Caught our Eye: Perspective on “Walking” Patient, Blood Stem Cells have a Helper and Three Clinical Trials at One Campus

Here are some stem cell stories that caught our eye this past week. Some are groundbreaking science, others are of personal interest to us, and still others are just fun.

Some perspective on nasal stem cells and ”walking” patient. PZ Meyers writing on ScienceBlogs did a good job of putting some perspective into the hype in many news outlets about the spinal cord injury patient who was treated with nasal stem cells. He starts out admitting he was “incredulous” that there was anything to the study, but after a thorough reading of the actual journal article he was convinced that there was some real, though modest gain in function for the patient. His conclusion:

“Sad to say, the improvements in the man’s motor and sensory ability are more limited and more realistic than most of the accounts would have you think.”

The research team actually reported on three patients. One got barely noticeable improvement; the patient in the news reports regained about 25 percent of function—which is indisputably a major gain in this population—and the third was somewhere in between.

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Meyer speculated about a reason for the improvements that was left out of most press reports. In addition to the stem cell harvested from the patients’ own nasal passages injected on either side of the injury the team also harvested nerve fibers from the patients legs and transplanted them across the site of the injury. They hoped the nerve strands would act as a bridge for the stem cells to grow and close the gap. It is also possible that being nerve cells they could provide the right cell-to-cell signals directing the nasal stem cells to become nerves. Meyers closed with an appropriate summary:

“I think there’s good reason to be optimistic and see some hope for an effective treatment for serious spinal cord injuries, but right now it has to be a realistic hope — progress has been made. A cure does not exist.”

Body’s own helper for blood stem cells found. In a case of the children ordering around the parents, a team at the Stowers Institute in Kansas City found that one of the progeny of blood-forming stem cells in the bone marrow can control the activity of the stem cells. In particular, they were looking at megacarocytes, the relatively rare bone marrow cells that normally produce the blood platelets you need for clotting a wound.

Blood stem cells are the most common stem cell therapy today, but one plagued by our limited ability to control their growth. Knowing this involvement of their offspring gives researcher a new avenue to search for ways to grow the much needed parent stem cells. Genetic Engineering & Biotechnology News wrote up the findings.

(Yes, I may be the only person in World Series-obsessed San Francisco writing something positive about Kansas City this week.)

Three clinical trails launched at just one campus. We have written individually about three clinical trials that began in the last month at the University of California, San Diego. Now, the university has written a good wrap up of the three trials that got posted to ScienceDaily.

Collectively, the three trials show the breadth of stem cell research starting to reach patients. One trial, for diabetes, uses cells derived from embryonic stem cells encased in a pouch to protect them from immune rejection. Another uses cells derived from fetal nerve stem cells to treat spinal cord injury. And the third involves a drug that targets the cancer stem cells that are believed to cause much of the spread of the disease and resistance to chemotherapy in cancer patients.

CIRM is funding two of the three trials and supported much of the basic science that led to the third. We expect to be funding 10 projects with approved clinical trials by the end of the year. The field is moving.

Don Gibbons

CIRM 2.0; saving time, saves lives

It’s been almost ten years since the voters of California approved Proposition 71, creating the Stem Cell Agency and giving us $3 billion to fund stem cell research. So this is an appropriate time to look back and see what we have done with the money so far, the progress that’s been made, and where we are heading in the next ten years.

Over the next few weeks we’ll be taking a more detailed look at all these elements – it’s too much to cover in one blog – but let’s start with where we’re heading. At yesterday’s meeting of our governing Board, the Independent Citizens Oversight Committee, President & CEO, C. Randal Mills, Ph.D. charted a course for future funding.

Randy Mills, Stem Cell Agency President & CEO

Randy Mills, Stem Cell Agency President & CEO

Right now it can take up to two years for a project going into clinical trials to apply for and get funding from us. As Randy said in a news release we issued after the meeting, “That’s just unacceptable”:

Under what he is calling CIRM 2.0, Randy is proposing to trim that down dramatically:

“We are going to shorten that to just 120 days. But we’re not just making it faster, we’re also making it easier for companies or institutions with a therapy that is ready to go into clinical trials to be able to get funding for their project when they need it. Under this new system they will be able to apply anytime, and not have to try and shoehorn their needs into our application process.”

The goal is not just to make it easier to apply for funding, but also to get more, high quality applications. Right now there is pressure on companies to apply before they are really ready because they know if they miss a current application deadline it could be another year to 18 months before another award cycle comes around. Under CIRM 2.0 application will be accepted on a monthly basis, so applicants won’t have to worry about missing one deadline – they can just apply the following month. Applying when they are ready will increase the likelihood that the projects will be and of high quality.

And as Randy points out, if it works at the clinical stage of funding, it can work at every stage:

“Speeding up the process, at all stages of research, just makes sense. The faster that researchers can get access to the funds they need to do their work, the faster they are likely to be able to produce something that helps patients.”

The speeding up of the process doesn’t just involve companies and researchers being able to apply anytime, it also means that when they do apply they’ll have to have all the supporting documentation and studies on hand to show they are ready to go as soon as the Board approves funding.

In the past there was often a delay of six months or even more after an application had been approved for funding while research milestones were negotiated and agreements signed. Because CIRM 2.0 will involve identifying milestones much earlier in the application process that delay will disappear.

This new approach involves a complete overhaul of the way we currently work but we think it’s worth it. We plan to start by introducing these changes for the projects that are furthest along, those ready to go into clinical trials, but in time we intend extending this to cover everything we fund.

Making these changes will help us trim a two-year process down to just three months. That means any therapy that proves successful is getting to the patients who need it much sooner than it otherwise would. And with many of the diseases we are targeting, saving time means saving lives.

October ICOC Board Meeting to Begin Soon

The October ICOC Board Meeting begins this morning in Los Angeles, CA.

The complete agenda can be found here, including a special Spotlight on Disease focusing on Retinitis Pigmentosa.

For those not able to attend, you are welcome to dial in!

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CIRM-Funded Scientists Make New Progress Toward Engineering a Human Esophagus

Creating tissues and organs from stem cells—often referred to as ‘tissue engineering’—is hard. But new research has discovered that the process may in fact be a little easier than we once thought, at least in some situations.

Engineered human esophageal tissue [Credit: The Saban Research Institute].

Engineered human esophageal tissue [Credit: The Saban Research Institute].

Last week, scientists at The Saban Research Institute of Children’s Hospital Los Angeles announced that the esophagus—the tube that transports food, liquid and saliva between the mouth and the stomach—can be grown inside animal models after injecting the right mix of early-stage, or ‘progenitor,’ esophageal cells.

These findings, published in the journal Tissue Engineering Part A, are an important step towards generating tissues and organs that have been damaged due to disease or—in some cases—never existed in the first place.

According to stem cell researcher Tracy Grikscheit, who led the CIRM-funded study, the researchers first implanted a biodegradable ‘scaffold’ into laboratory mice. They then injected human progenitor cells into the mice and watched as they first traveled to the correct location—and then began to grow. The ability to both migrate to the right location and differentiate into the right cell type, without the need for any external coaxing, is crucial if scientists are to successfully engineer such a critical type of tissue.

“Different progenitor cells can find the right ‘partner’ in order to grow into specific esophageal cell types—and without the need for [outside] growth factors,” explained Grikscheit in a news release. “This means that successful tissue engineering of the esophagus is simpler than we previously thought.”

Grikscheit, who is also a pediatric surgeon as Children’s Hospital Los Angeles, was particularly hopeful with how their findings might one day be used to treat children born with portions of the esophagus missing—as well as adults suffering from esophageal cancer, the fastest-growing cancer in the U.S.

“We have demonstrated that a simple and versatile, biodegradable polymer is sufficient for the growth of a tissue-engineered esophagus from human cells. This not only serves as a potential source of tissue, but also a source of knowledge—as there are no other robust models available for studying esophageal stem cell dynamics.”

Want to learn more about tissue engineering? Check out these video highlights from a recent CIRM Workshop on the field.

Stem cell stories that caught our eye: Some good news got a little overplayed on blindness and Alzheimer’s

Here are some stem cell stories that caught our eye this past week. Some are groundbreaking science, others are of personal interest to us, and still others are just fun.

Stories on blindness show too much wide-eyed wonder. While our field got some very good news this week when Advanced Cell Technologies (ACT) published data on its first 18 patients treated for two blinding diseases, many of the news stories were a little too positive. The San Diego Union Tribune ran the story from Associated Press writer Maria Cheng who produced an appropriately measured piece. She led with the main point of this early-phase study—the cells implanted seem to be safe—and discussed “improved vision” in half the patients. She did not imply their sight came back to normal. Her third paragraph had a quote from a leading voice in the field Chris Mason of University College London:

“It’s a wonderful first step but it doesn’t prove that (stem cells) work.”

The ACT team implanted a type of cell called RPE cells made from embryonic stem cells. Those cells are damaged in the two forms of blindness tested in this trial, Stargardt’s macular dystrophy and age-related macular degeneration, the leading cause of blindness in the elderly. Some of the patients have been followed for three years after the cell transplants, which provides the best evidence to date that cells derived from embryonic stem cells can be safe. And some of the patients regained useful levels of vision, which with this small study you still have to consider other possible reasons for the improvement, but it is certainly a positive sign.

CIRM funds a team using a different approach to replacing the RPE cells in these patients and they expect to begin a clinical trial late this year

Stem cells create stronger bone with nanoparticles.   Getting a person’s own stem cells to repair bad breaks in their bones certainly seems more humane than hacking out a piece of healthy bone from some place else on their body and moving it to the damaged area. But our own stem cells often can’t mend anything more than minor breaks. So, a team from Keele University and the University of Nottingham in the U.K. laced magnetic nanoparticles with growth factors that stimulate stem cell growth and used external magnets to hold the particles at the site of injury after they were injected.

It worked nicely in laboratory models as reported in the journal Stem Cells Translational Medicine, and reported on the web site benzinga. Now comes the hard step of proving it is safe to test in humans

Stem cells might end chronic shortage of blood platelets. Blood platelets—a staple of cancer therapy because they get depleted by chemotherapy and radiation—too often are in short supply. They can only set on the shelf for five days after a donation. If we could generate them from stem cells, they could be made on demand, but you’d have to make many different versions to match various peoples’ blood type. The latter has been a bit of a moot point since no one has been able to make clinical grade platelets from stem cells.

plateletsA paper published today by Advanced Cell Technologies may have solved the platelet production hurdle and the immune matching all at once. (ACT is having a good week.) They produced platelets in large quantities from reprogrammed iPS type stem cells without using any of the ingredients that make many iPS cells unusable for human therapy. And before they made the platelets, they deleted the gene in the stem cells responsible for the bulk of immune rejection. So, they may have created a so-called “universal” donor.

They published their method in Stem Cell Reports and Reuters picked up their press release. Let’s see if the claims hold up.

Alzheimer’s in a dish—for the second time. My old colleagues at Harvard got a little more credit than they deserved this week. Numerous outlets, including the Boston Globe, picked up a piece by The New York Times’ Gina Kolata crediting them with creating a model of Alzheimer’s in a lab dish for the first time. This was actually done by CIRM-grantee Lawrence Goldstein at the University of California, San Diego, a couple years ago.

But there were some significant differences in what the teams did do. Goldstein’s lab created iPS type stem cells from skin samples of patients who had a genetic form of the disease. They matured those into nerve cells and did see increased secretion of the two proteins, tau and amyloid-beta, found in the nerves of Alzheimer’s patients. But they did not see those proteins turn into the plaques and tangles thought to wreak havoc in the disease. The Harvard team did, which they attributed, in part, to growing the cells in a 3-dimensional gel that let the nerves grow more like they would normally.

The Harvard team, however, started with embryonic stem cells, matured them into nerves, and then artificially introduced the Alzheimer’s-associated gene. They have already begun using the model system to screen existing drugs for candidates that might be able to clear or prevent the plaques and tangles. But they introduced the gene in such a way the nerve cells over express the disease gene, so it is not certain the model will accurately predict successful therapies in patients.

Don Gibbons

UCLA Study Suggests New Way to Mend a Broken Heart

When you suffer a heart attack, your heart-muscle cells become deprived of oxygen. Without oxygen, the cells soon whither and die—and are entombed within scar tissue. And once these cells die, they can’t be brought back to life.

But maybe—just maybe—there is another way to build new heart muscle. And if there is, scientists like Dr. Arjun Deb at the University of California, Los Angeles (UCLA), are hot on the trail to find it.

Scar forming cells (in red) in a region of the injured heart expressing blood vessel cell marker in green and thus appearing yellow (see arrows). This study observed that approximately a third of the scar-forming cells in the injured region of the heart adopted "blood vessel" cell-like characteristics. [Credit: Dr. Arjun Deb/Nature]

Scar forming cells (in red) in a region of the injured heart expressing blood vessel cell marker in green and thus appearing yellow (see arrows). This study observed that approximately a third of the scar-forming cells in the injured region of the heart adopted “blood vessel” cell-like characteristics. [Credit: Dr. Arjun Deb/Nature]

Published yesterday in the journal Nature, Deb and his team at UCLA’s Eli & Edythe Broad Center for Regenerative Medicine and Stem Cell Research have found some scar-forming cells in the heart have the ability to become blood vessel-forming cells—if given the proper chemical ‘boost.’

“It is well known that increasing the number of blood vessels in the injured heart following a heart attack improves its ability to heal,” said Deb. “We know that scar tissue in the heart is associated with poor prognosis. Reversing or preventing scar tissue from forming has been one of the major challenges in cardiovascular medicine.”

Tackling the ever-growing problem in heart disease can seem an almost insurmountable task. While heart disease claims more lives worldwide than any other disease, advances in modern medicine in recent decades mean that more and more people are surviving heart attacks, and living with what’s called ‘heart failure,’ for their hearts can no longer beat at full capacity, and they have trouble taking long walks or even going up a flight of stairs.

Transforming this scar tissue into functioning heart muscle has therefore been the focus of many research teams, including CIRM grantees such as Drs. Deepak Srivastava and Eduardo Marbán, who have each tackled the problem from different angles. Late last year, treatment first designed by Marbán and developed by Capricor Therapeutics got the green light for a Phase 2 Clinical Trial.

In this study, Deb and his team focused on scar-forming cells, called fibroblasts, and blood-vessel forming cells, called endothelial cells. Previously, experiments in mice revealed that many fibroblasts literally transformed into endothelial cells—and helped contribute to blood vessel formation in the injured area of the heart. The team noted this phenomenon has been called the mesenchymal-endothelial transition, or MEndoT.

In this study, the researchers identified the molecular mechanism behind MEndoT—and further identified a small molecule that can enhance this transition, thus boosting the formation of blood vessels in the injured heart. This study bolsters the idea of focusing on the creation of blood vessels as a way to help reverse damage caused by a heart attack. Said Deb:

“Our findings suggest the possibility of coaxing scar-forming cells in the heart to change their identity into blood vessel-forming cells, which could potentially be a useful approach to better heart repair.”

The Nose Knows: Stem Cells are Vital Players in Brain Circuits Responsible for Smell

Ah, the smell of coffee! You can thank your olfactory bulb.

Ah, the smell of coffee! You can thank your olfactory bulb.

Ah, the mouth-watering scent of freshly baked bread and the intense aroma of roasted coffee beans. You can thank nerve cells in the front of your brain — in direct contact with your nasal passages — that convert odor molecules in the air into brain signals and generate your perception of those wonderful smells.

Loss of the sense of smell is often one of the earliest symptoms in people stricken with brain disorders such as Parkinson’s and Alzheimer’s. So the study of this part of the brain called the olfactory bulb, that’s responsible for smell perception, is an attractive area of research that could help provide insights into fundamental brain function and its connection to neurodegenerative diseases. Last week, scientists at the National Institutes of Health (NIH) moved the field a step forward by reporting in the Journal of Neuroscience that brain stem cells play a vital role in sustaining the proper brain cell circuitry in the olfactory bulb.

Studies in adult mice have shown that brain stem cells deep inside the brain have the uncanny ability to travel to the olfactory bulb, transform into nerve cells, and set up appropriate circuits with surrounding nerve cells. The NIH team had previously demonstrated that when a nostril is plugged for 20 days in these mouse studies, depriving the olfactory system of stimulation, the nerve cell connections scatter and become very disorganized. But after removing the plug for 40 days the proper connections and patterns are re-established.

The brain stem cells uncanny ability to migrate through the thin rostral stream, transform in to neurons, and make the right connections with surrounding neurons in the olfactory bulb, the large structure in the upper right. (Image credit:  Belluscio Lab, NINDS).

Newly born nerve cells migrate along a thin path and connect up with surrounding nerve cells in the olfactory bulb, the large structure in the upper right. (Image credit: Belluscio Lab, NINDS).

In the current study, the team used genetic engineering techniques to precisely remove only those brain stem cells in adult mice that transform into the olfactory nerve cells. Again when a nostril was plugged the nerve cell connections were disrupted. But this time when the brain stem cells were eliminated and the nose plug removed, the nerve cell connections remained disorganized. This result reveals that the system relies on a replenishing supply of brain stem cells. As senior author Leonardo Belluscio, Ph.D. states in a NIH press release:

“We found that without the introduction of the new neurons, the system could not recover from its disrupted state.”

Even when the brain stem cells were eliminated in mice that were not given the nose block, a deterioration of the olfactory bulb nerve cell network was still observed by the research team. These results turn scientists’ understanding of brain circuits on its head: rather than being mostly stable structures, in this case the olfactory brain circuits appear unstable by default and must continually receive new neurons (from stem cells) to not only restore disrupted connections but also to preserve stable circuits.

Dr. Belluscio reflected on these intriguing results and its implications for neurologic disease:

“This is an exciting area of science. I believe the olfactory system is very sensitive to changes in neural activity and given its connection to other brain regions, it could lend insight into the relationship between olfactory loss and many brain disorders.”

To hear more from Dr. Belluscio about these results, watch this video interview. And for more about the role of stem cells in adult brain circuitry, watch this seminar by UCSF researcher and CIRM grantee Arturo Alvarez-Buylla, PhD.