The Humans of the Wyss (HOW) series features members of the Wyss community discussing their work, the influences that shape them as professionals, and their collaborations at the Wyss Institute and beyond.
David Chou’s work is literally out of this world! In addition to identifying radiation countermeasures for use on Earth, he is part of the AVATAR project, which aims to understand how humans respond to the health risks inherent to spaceflight. As a physician-scientist, he’s equally excited about developing therapeutics and contributing to humanity’s future beyond our planet. Learn more about David and his work in this month’s Humans of the Wyss.
What are you working on?
I have two major projects, both related to radiation. The first is a BARDA-funded program focused on identifying countermeasures to help the body recover more quickly after ionizing radiation exposure. It’s a collaborative effort among multiple teams at the Wyss, using Organ Chips that mimic the bone marrow, the lungs, the intestines, and lymphoid follicles. We’re also working with the team that studies blood coagulation, because it’s thought that one of the primary drivers of tissue injury after radiation exposure is damage to the blood vessels, which leads to a variety of inflammatory and clotting issues. Plus, we’re working with the computational and proteomics groups to repurpose existing drugs and identify biomarkers of radiation injury.
The second is called AVATAR, which is focused on trying to understand how the human body responds to spaceflight and the space environment. It turns out that radiation exposure is one of the most important health risks inherent to the space environment.
To do this, we’re comparing two sets of Bone Marrow Chips containing cells derived from the astronauts on the recent Artemis II mission. One set stayed on Earth while the other traveled around the moon with the crew. Any differences that we observe will be further referenced against the changes we detect in pre-flight versus post-flight blood from the astronauts themselves.
What real-world problems do these solve?
The immediate application of the first project is to find therapies for people exposed to high doses of ionizing radiation. This could occur in a combat scenario, an industrial accident related to nuclear power, or in a medical setting like radiation therapy for cancer.
The AVATAR project’s overall goal is to keep humans healthy as we explore and eventually colonize space. This requires that we understand how the body adapts to the space environment. Right now, the best way to do that is to study astronauts, but this becomes a bottleneck when you consider how diverse the human population is compared to the small number of people who currently go into space. Plus, with living humans, you cannot study all the cell types you might want to.
So, AVATAR is a proof of concept to show that we can use Organ Chips to study how space affects people at an individual level. In the future, we could send up chips created with cells derived from people of different ages, with different medical comorbidities, and with different genetic backgrounds. That would enable us to study the effects of spaceflight on a much larger scale than we do now.
1/4 David, along with team members Ela Contreras Panta and Prince Saini, outside of the Kennedy Space Center. Credit: David Chou and Ela Contreras Panta 
2/4 David got to watch the launch of the Artemis II alongside team members Chris Lee and Ela Contreras Panta. Credit: David Chou 
3/4 David took a quick selfie with the Artemis II payload after it came back from its journey around the moon, featuring the crew members' signatures. Credit: David Chou 
4/4 David and his team members, Prince Saini and Ela Contreras Panta, had the chance to meet retired astronaut Sunita Williams when she visited the Wyss Institute in April. Credit: David Chou
What inspired you to get into this field?
I decided to attend medical school at the University of Pittsburgh because they offered me something called the Dean’s Merit Scholarship. This covered my tuition and was meant to encourage students to partake in activities outside of clinical practice, such as teaching, research, or community service. As a first-year medical student, I attended a lunchtime talk featuring another student who had just returned from what she described as the best year of her life. She had spent a year at the NIH as part of a program that was called the HHMI-NIH Research Scholars Program. This program accepted about 40 medical, dental, and other graduate-level health students from across the country every year, and they all lived together at the NIH Bethesda campus.
Building happens in science through the creation of new technologies and a new understanding of the world
I was lucky enough to be accepted into the program and joined the lab of Yasmine Belkaid. Being in a wonderful group environment that encouraged me to explore science and ask my own questions was exhilarating. Furthermore, the program brought in top-notch NIH and HHMI investigators to speak to us at weekly Monday night dinners. This experience made me fall in love with research, and what was initially supposed to be a year turned into four years and a Ph.D. from the University of Paris, though all my work was actually done at the NIH. I am grateful that the University of Pittsburgh was flexible enough to allow me to take that time off before returning to finish my medical degree.
What continues to motivate you?
I have two north stars guiding me – two things that I want to be true when I look back on my career. The first is that I want to be able to say that the people I worked with, especially the people I helped supervise, are better off as a result of our time together. The second is that I want to be able to point to a therapy that improves patients’ lives and say that it exists because of the work that I did.
I want to be able to say that the people I worked with, especially the people I helped supervise, are better off as a result of our time together [and] I want to be able to point to a therapy that improves patients’ lives and say that it exists because of the work that I did.
What excites you the most about your work?
The most exciting aspect of the radiation project is therapeutic development. We’re using biological and computational tools to identify both existing and novel compounds that could accelerate the body’s healing process after radiation exposure.
All the work we are doing now to figure out how to keep people healthy in space will contribute, at least in a small way, to the foundation that enables that future.
For the AVATAR project, it’s the opportunity to contribute to what could be a significant part of humanity’s future. If I envision humankind 500-1,000 years from now, I find it hard to imagine that we won’t have expanded beyond our current planet. All the work we are doing now to figure out how to keep people healthy in space will contribute, at least in a small way, to the foundation that enables that future.
What are some of the challenges that you face?
The most challenging part of the radiation project is thinking about what comes next. How do we turn what we’re doing in the lab into something that could be used to treat people? It’s not a therapeutic area like lung cancer or heart disease, where there’s a clear commercial opportunity. Ideally, we would never need to use radiation countermeasures to treat total body exposure to high doses of ionizing radiation. Finding the right translational path involves being creative about what other health-related issues these therapies could address, for example, the myriad side effects of cancer radiation therapy.
The most difficult part of the AVATAR project is that there’s so much we don’t know. We have to find the right questions to ask that will lead to answers that could actually make a difference in the field. We also want to validate our results with human data, and there isn’t a ton of data on people who have gone into space.
Why did you want to work at the Wyss?
I came to Boston after medical school to finish my clinical training at Massachusetts General Hospital, where I completed anatomic pathology residency and hematopathology fellowship. When I was trying to decide what I wanted to do for my postdoc, I interviewed with Wyss Founding Director Donald Ingber, who was looking to create an Organ Chip model of the bone marrow to study the effects of radiation. Being a physician-scientist with a background in pathology, I knew I wanted to conduct research using human cells and tissues. The project appealed to me because I could apply my expertise and make a translational impact.
What is unique about the Wyss?
I had my formative research experience in the Belkaid lab at the NIH, which, at the time, was investigating the basic biology underlying immune regulation and host-commensal interactions. By comparison, the Wyss is much more translationally focused. At an institutional level, the Wyss also does a much better job of communicating the importance of its work and presenting itself to non-scientists than the NIH.
How do you collaborate with and/or receive support from teams across the Wyss Institute?
With so many teams collaborating on the radiation project, we have monthly meetings to review what everyone is working on as well as their progress toward milestones and our ultimate goals. Then, of course, there are ad hoc discussions in between.
One team we get a lot of support from is the Sponsored Research Team. They interface directly with the funding agencies, send in all of the invoices, help us track our budgets, and track which personnel are on which contract. The Operations and Facilities Teams are also hugely important to our work because they keep our labs safe and operational.
How have your previous work and personal experiences shaped your approach to your work today?
Being trained as a pathologist and maintaining a connection to the pathology department at Mass General Brigham has enabled not just my group but multiple groups within the Wyss to access human tissue and cells that are critical to their projects. I’d especially like to acknowledge Robert Hasserjian’s continued support here. I think my medical training also underlies my desire to help create new therapies for patients that can meaningfully improve their lives.
What do you like to do outside of work?
I like to read, usually science fiction. What currently takes up most of my time is playing with my eight-month-old son.
What’s something fun about you that someone wouldn’t know from your resume?
I sing, mostly for fun, on my own. I took voice lessons when the pandemic hit, and I’ve been singing on and off since then.
If you had to choose an entirely different career path, what would it be?
I have a lot of respect for people who build things. That building happens in science through the creation of new technologies and a new understanding of the world, but it also happens in many other fields. So, I think I would still like to be someone who builds things, maybe within engineering. I think I’d go with a software engineer because of how quickly one can build in that field.
What does it feel like to be working on cutting-edge technologies that have the potential to have a real and significant impact on people’s lives and society?
That’s one of my main drivers. I don’t know if it’s a feeling so much as a significant part of why I’m doing what I’m doing. It enables me to work the hours I do, despite being busy outside of work, and it’s what keeps me motivated when things get difficult.