CIRM Scholar Spotlight: Matt Donne on Lung Stem Cells

CIRM has funded a number of educational and research training programs over the past ten years to give younger students and graduate/postdoc scholars the opportunity to explore stem cell science.

Two of the main programs we support are the Bridges and the CIRM Scholars Training Program. These programs fund future scientists from an undergraduate to postdoctoral level with a goal of creating “training programs that will significantly enhance the technical skills, knowledge, and experience of a diverse cohort of… trainees in the development of stem cell based therapies.”

The Stem Cellar team was interested to hear from Bridges and CIRM scholars themselves about their experience with these programs, how their careers have benefited from CIRM funding, and what research accomplishments they have under their belt. We were able to track some of these scholars down, and will be publishing a series of interview-style blogs featuring them over the next few months.

Matt Donne

Matt Donne

We start off with a Matt Donne, a PhD student at the University of California, San Francisco (UCSF) in the Developmental and Stem Cell Biology graduate program. Matt is a talented scientist and has a pretty cool story about his research training path. I sat down with Matt to ask him a few questions.

Q: Tell us how you got into a Stem Cell graduate program at UCSF.

MD: I was fortunate to have Dr. Carmen Domingo from San Francisco State support my application into the CIRM Bridges Program. I’d been working for Dr. Susan Fisher at UCSF for a couple of years and realized that I wanted to get a PhD and go to UCSF. I thought the best way to do that was improve my GPA and get a masters degree in stem cell biology. I applied to the CIRM program at SF State, and was accepted.

The Bridges Program has been a great feeder platform to get students more science experience exposure than they would have otherwise received, and prepares them well to move on to competitive graduate schools.

After receiving my Masters degree, I was admitted into the first year of the Developmental and Stem Cell Biology program at UCSF. When the opportunity to apply for a training grant from CIRM came about between my first and second year of at UCSF, I knew I had to give it a chance and apply. With the help of my mentor, Dr. Jason Rock, I wrote a solid proposal and was awarded the fellowship.

While at SF State, Carmen was extremely supportive and always available for her students. Since then, many of us still keep in touch and more have joined the UCSF graduate school community.

Q: Can you describe your graduate research?

MD: The field of regenerative medicine is searching for ways to allow us to repair injuries similar to how the Marvel Comic Wolverine can repair his wounds in the movies. One interesting fact which has been known for several decades, but has not been able to be investigated more deeply until now, is the innate ability for the adult lung to regrow lost lung tissue without any sort of intervention. My thesis focuses on defining the molecular mechanisms and stem cell niches that allow for this normal, healthy adult lung tissue growth. The working hypothesis is if we can understand what makes a cell undergo healthy tissue proliferation and differentiation, we could stimulate this response to cure individuals who suffer from diseases such as chronic obstructive pulmonary disease (COPD). Similarly, if we understand how a cell decides to respond in a diseased way, we could stop or revert the disease process from occurring.

One of the models we use in our lab is a “pneumosphere” culture. We essentially grow alveoli, which are the site of gas exchange in the lung, in a dish to attempt to understand how specific alveolar stem cells signal and interact with one another. This information will teach us how these cells behave so we can in turn either promote a healthy response to injury or, potentially, stop the progression of unhealthy cell responses. The technique of growing alveoli in a dish allows us to cut down on the “noise” and focus on major cellular pathways, which we can then more selectively apply to our mouse model systems.

Pneumospheres. (Photo by Matt Donne)

Pneumospheres or “lung cells in a dish”. (Photo by Matt Donne)

Lung cells.

Lung pneumospheres under a microscope. (Photo by Matt Donne)

We are now in the process of submitting a paper demonstrating some of the molecular players that are involved in this regenerative lung response. Hopefully the reviewers will think our paper is as awesome we as believe it to be.

Q: How has being a CIRM scholar benefited your graduate research career?

MD: Starting in my second year at UCSF, I was awarded the CIRM fellowship. I think it helped the lab to have the majority of my stipend covered through the CIRM fellowship, and personally I was very excited about the $5,000 discretionary budget. These monies allowed me to go to conferences every year for the past three years, and also have helped to support the costs of my experiments.

The first conference I attended was a Gordon Conference in Italy on Developmental Biology. There I was able to learn more about the field and also make friends with many professors, students, and postdocs from around the world. Last year, I went to my first lung-specific conference, and attended again this year. That has been one of the highlights of my PhD career. While there, one is able to speak and interact with professors whose names are seen in many textbooks and published papers. I never thought I would be able to so casually interact with them and develop relationships. Since then, I have been able to work on small collaborations with professors from across the US.

It was great that I could go to these conferences and establish important relationships with professors without being a major financial burden to my Professor. Plus, it has been hugely beneficial for my career as I now have professors whom I can reach out to as I look towards my future as a scientist.

Q: What other benefits did the CIRM scholars program provide you?

MD: Dr. Susan Fisher has been in charge of the CIRM program at UCSF. She organized lunch-time research talks that involved both academic as well as non-academic leaders in the field. I enjoyed the extra exposure to new fields of stem cell biology as well as the ability to learn more about the start-up and non-academic world. There are not many programs that offer this type of experience, and I felt fortunate to be a part of it. Also, the free lunches on occasion were a nice perk for a grad student living in San Francisco!

I attended the CIRM organized conferences whenever they happened. It’s always great presenting at or attending poster sessions at these events, seeing familiar faces and meeting new people. I took full advantage of the learning and networking that CIRM allowed me to do. The CIRM elevator pitch competition was really cool too. I didn’t win, came in third, but I enjoyed the challenge of trying to break down my thesis project into a digestible one-minute pitch.

Q: Where do you see the field of lung biology and regenerative medicine heading?

MD: My take away from the research conferences I have attended with the help of CIRM-funding is that we are in a very exciting time for lung stem cell research. The field overall is still young, but there are many labs across the world now working on a “lung mapping project” to better define stem cell populations in the lung. I see this research in the future translating in to regenerative therapies by which diseased cells/tissue will be targeted to actually stop the disease progression, and in turn possibly repair and regenerate healthy new tissue. This research has wide reaching implications as it has the potential to help everyone from a premature baby more quickly develop mature healthy lungs, to adults suffering from COPD brought on by environmental factors, such as air pollution. As many scientists are often quoted, “This is a very exciting time for our field.”

Q: What are your future plans?

MD: I expect to graduate in about a year’s time. In the future, I want to pursue a career focusing on the social impact of science. I aspire to be someone like UCSF’s former chancellor Dr. Susan Desmond-Hellmand. It’s really cool to go from someone who was the president of product development at Genentech, to chancellor at UCSF, to now president of the Bill and Melinda Gates Foundation. Bringing science to impact society in that way is what I hope to do with my future.

Related links:

Using satellites to build bigger biceps

Arnold Schwarzenegger: Photo courtesy

Arnold Schwarzenegger:
Photo courtesy

There are several ways you can build bigger, stronger muscles. You can take the approach favored by our former Governor, Arnold Schwarzenegger, and pump iron till your biceps are as inflated as a birthday balloon. Or you could follow the lead of a research team we are funding and try to use stem cells to do the trick.

Our muscles contain a group of stem cells called satellite cells. These normally lie dormant until the muscle is damaged and then they spring into action to repair the injury. However, satellite cells are relatively rare and are hidden in the muscle itself, making them hard to find and notoriously difficult to study. In the past researchers have struggled to get these satellite cells to grow outside the body, which made it difficult to study muscle regeneration and develop new ways of treating muscle problems.

Finding a solution

Now a team at the University of California, San Francisco has found a solution to the problem. They started by analyzing samples of 7 different kinds of muscles (in the body, legs and head) from 43 patients. In all but two samples they found that the gene PAX7 was specifically turned on in satellite cells and the PAX7 protein was present with little variation from one muscle group to another.

Upon further sleuthing, they discovered that PAX7-positive satellite cells were the real deal because they also expressed two common cell surface markers of human satellite cells: CD29 and CD56.

The researchers then transplanted PAX7-positive cells into mice that had experienced muscle injuries. As they report in the journal Stem Cell Reports these cells not only engrafted in the mice but they also created hundreds of human-derived muscle fibers. This finding shows that satellite cells were regenerating and potentially helping to heal the damaged muscle.

What’s next

As always, anything done in mice is interesting but still needs to be replicated in people before we know for sure we are on to something.

In their conclusion the team freely admit this is just a first step but, compared to where we were before, it’s a very important step. As senior author Jason Pomerantz says:

“This is the first definitive experimental description of adult human endogenous muscle stem cell function.”

Harnessing the power of satellite cells would be of tremendous benefit to people suffering from facial paralysis, loss of hand function or muscle-wasting diseases such as sarcopenia, and could even be used as a way to deliver gene therapy to people with muscular dystrophies.

Using satellite cells to do all that, would be out of this world.

Moving Beyond Current CIRM Funding

Delivering on CIRM’s mission of “accelerating stem cell treatments to patients with unmet medical needs” requires the participation of multiple stakeholders to span the research, development, and commercialization phases of bringing a new product to market. In this post, I am pleased to highlight two recent examples of CIRM-funded projects moving beyond their period of CIRM funding by establishing partnerships with industry and investors to further develop the underlying CIRM-funded technology.

In 2000, Dr. Jill Helms, an academic investigator at Stanford University, received a $6.5 million grant from CIRM under an Early Translational award. The title of Dr. Helms’ project was Enhancing Healing via Wnt-Protein Mediated Activation of Endogenous Stem Cells,” and the goal of the award was to develop a novel, protein-based therapeutic platform to accelerate and enhance tissue regeneration through activation of adult stem cells. The five-year award achieved many critical milestones along the way, including the initiation of two preclinical studies aimed at demonstrating the effectiveness of a protein called L-WNT3A to improve the success of spinal fusion surgery and to treat a degradative bone disease called osteonecrosis, both of which represent unmet medical needs.


Through CIRM funding, Dr. Jill Helms’ team was able to demonstrate that treatment with a protein called L-Wnt3a regenerates and promotes bone formation in animals models (Figs D,F: untreated; Figs E,G: Wnt3a treated). (image credit: Leucht et al. J Bone Joint Surg Am. 2013;95:1278-88)

Dr. Helms’ work attracted considerable interest from the investor community during the lifespan of her grant, and during the final year of her award Dr. Helms’ WNT3A technology platform was successfully spun out of Stanford into a newly created company called Ankasa Regenerative Therapeutics. Ankasa was established with the financial support of Avalon Ventures – a La Jolla based life sciences venture capital firm, Correlation Ventures – an analytics driven venture capital firm, and Heraeus Medical – a diversified global medical device company based in Germany with over $1 billion of annual revenue. Ankasa has raised an initial $8.5 million in the first round of the total $17 million Series A financing to continue the development of the previously CIRM-funded technology.

Moving Radially Branched Deployment_Neurosurgery_Lim

Dr. Daniel Lim’s CIRM-funded BranchPoint Device allows neurosurgeons to deliver cell based therapies to multiple areas of the brain with just one needle penetration.  (image credit: Silvestrini et al. Stereotact Funct Neurosurg 2013;91:92–103)

The second recent example comes from a CIRM Tools & Technology grant to Dr. Daniel Lim, a neurosurgeon at UCSF. Dr. Lim was awarded a $1.8 million grant to develop a more efficient device for transplanting stem cells into the brain, titled Development and Preclinical Testing of New Devices for Cell Transplantation to the Brain.” Dr. Lim successfully developed a platform technology that enables Radially Branched Deployment (RBD) of cells to multiple target locations at variable radial distances and depths along the initial brain penetration tract with real-time interventional magnetic resonance image (iMRI) guidance. This technology is a huge leap forward over the conventional and crude syringe and needle device that are typically used to inject living cells into the brain.

Dr. Lim’s work attracted the attention of Accurexa, a publicly traded medical device company that licensed the CIRM-funded technology from UCSF. Under the guidance of Accurexa, a 510(k) application was submitted to the FDA for the newly coined “BranchPoint Device.” In June of this year, Accurexa successfully raised $2.5 million in equity financing to continue the development and for commercialization of the BranchPoint Device.

Overall, there remains a lack of industry pull for early stage stem cell technologies, however, both Drs. Helms and Lim’s stories represent successful examples of CIRM providing public dollars for early stage research with the resulting potentially life-saving applications attracting interest from investors and companies. These new investors will further fund and develop the technologies well beyond current CIRM funding and, assuming they are successful, deliver them to patients with unmet medical needs.

Creaky Cell Machinery Affects the Aging Immune System, CIRM-Funded Study Finds

Why do our immune systems weaken over time? Why are people over the age of 60 more susceptible to life-threatening infections and many forms of cancer? There’s no one answer to these questions—but scientists at the University of California, San Francisco (UCSF), have uncovered an important mechanism behind this phenomenon.

Reporting in the latest issue of the journal Nature, UCSF’s Dr. Emmanuelle Passegué and her team describe how blood and immune cells must be continually replenished over the lifetime of an organism. As that organism ages the complex cellular machinery that churns out new cells begins to falter. And when that happens, the body can become more susceptible to deadly infections, such as pneumonia.

As Passegué so definitively put it in a UCSF news release:

“We have found the cellular mechanism responsible for the inability of blood-forming cells to maintain blood production over time in an old organism, and have identified molecular defects that could be restored for rejuvenation therapies.”

The research team, which examined this mechanism in old mice, focused their efforts on hematopoetic stem cells—a type of stem cell that is responsible for producing new blood and immune cells. These stem cells are present throughout an organism’s lifetime, regularly dividing to preserve their own numbers.

Molecular tags of DNA damage are highlighted in green in blood-forming stem cells. [Credit: UCSF]

Molecular tags of DNA damage are highlighted in green in blood-forming stem cells. [Credit: UCSF]

But in an aging organism, these cells’ ability to generate new copies is not as good as it used to be. When the research team dug deeper they found a key bit of cellular machinery, called the mini-chromosome maintenance helicase, breaks down. When that happens, the DNA inside the cell can’t replicate itself properly—and the newly generated cell is not running on all cylinders.

One of the first things that these old stem cells lose as a result is their ability to make B cells. B cells, a key component of the immune system, normally make antibodies that fight infection. As B cell numbers dwindle in an aging organism, so too does their ability to fight infection. As a result the organism’s risk for contracting dangerous illnesses skyrockets.

This research, which was funded in part by CIRM, not only informs what goes wrong in an aging organism at the molecular level, but also points to new targets that could keep these stem cells functioning at full capacity, helping promote so-called ‘healthy aging.’ As Passegué added:

“Everybody talks about healthier aging. The decline of stem-cell function is a big part of age-related problems. Achieving longer lives relies in part on achieving a better understanding of why stem cells are not able to maintain optimal functioning.”