Whitson, a biochemist with more than 38 years of space and science experience at NASA, is currently vice president of Human Spaceflight for Axiom Space, the only company with human spaceflight experience on board the International Space Station. She has flown on two Axiom Space commercial astronaut missions in addition to her three NASA long-duration spaceflights.  

Whitson sat down for a “fireside chat” with Arun Sharma, PhD, director of the Cedars-Sinai Center for Space Medicine Research.

Here is an excerpt from their conversation:

Arun Sharma: What are you most excited about, sciencewise, for the next generation of Axiom Space missions?

Peggy Whitson: Part of the reason I was excited to join Axiom Space was the fact that one of their goals is manufacturing in space, and I really wanted to see some of that exciting research take that next step. I think we are going to be able to unlock microgravity, use it as a tool for expanding our capabilities and then bring that capability back to Earth.

What capabilities do you think are critical for the next generation of life science in space?

I think the most important thing is having the capability to analyze and assess on board what's happening, get the data to the ground quickly and have it already processed using orbital data centers. Orbital data centers and data architecture will allow us to do iterative science and process and analyze information in real time on board. I think that will be game changing because it will allow us to quickly take advantage of new ideas that come out of the data.

When it comes to designing experiments for research in space, what should investigators consider?

The biggest thing from a safety perspective is containment. We must be able to protect the crew. And in some cases, we're protecting what we're working on from the crew. Sometimes creating this containment can take away from the ease with which we can do investigations. So I think the right balance needs to be assessed for each investigation.

Another thing to consider is that in the past we thought we had to make everything special for space. But we found a lot of things just off the shelf will work. So take the simplest route first, and try and use as much as possible off the shelf. It costs a lot less than it does to start from scratch and develop all new hardware.

Space is going to become more accessible. So we will have a chance to learn not just how selected astronauts respond to space, but how an everyday person responds to this unique situation. Talk to us about the concept of space for everybody, and what you and Axiom Space are doing to support that vision.

One of the investigations we did on our Axiom Mission 4 (Ax-4) was called Suite Ride, and it looked at insulin response in microgravity. We studied off-the-shelf techniques for monitoring glucose, and tested stability for the insulin on board and injection techniques— demonstrating that diabetes tools operate accurately in space. That's one specific example of how we are looking at opening up access to space.

What do you see as the role of a major academic medical center like Cedars-Sinai in the space ecosystem?

Space offers some unique opportunities, and organizations like Cedars-Sinai have the capability of taking that to the next level by enabling in-space biomanufacturing of advanced materials that we cannot make on Earth to benefit patients everywhere. This research in microgravity will provide the science community the opportunity to develop disease models, helping us better understand diseases to make new drugs and drug therapies for patients. This is an important role that Cedars-Sinai plays in opening up space to other organizations and researchers by just showing them what's possible from a medical perspective.

Do you have advice for students and other trainees who might ultimately pursue careers in space medicine?

Adaptability is important. And I think collaboration is incredibly important when you're working in space. You have to be able to trust people that you're working with. You have to be able to communicate effectively.

I applied to be an astronaut for over 10 years and was rejected until the 10th year. But those 10 years were some of the most valuable because of the experience I gained. It doesn't have to be a straight line to get where you want to go if you are pursuing your goals. Take advantage of the experiences that you have and learn from them. Don't be afraid of failing. You learn from that, and then you make the next run better.

Cedars-Sinai Health Sciences University is advancing groundbreaking research and educating future leaders in medicine, biomedical sciences and allied health sciences. Learn more about the university.

The investigators want to study how the weakened gravitational pull in space affects the growth of organoids—small collections of cells that emulate the form and function of human organs. Scientists use organoids to model diseases and test drugs, and the hope is that they will grow more quickly in space than on Earth.

Putting Research Into Practice

“Our ultimate goal is to accelerate the progress of biological research and discovery,” said Arun Sharma, PhD, director of the Center for Space Medicine Research and research scientist in the Board of Governors Regenerative Medicine Institute at Cedars-Sinai. “Our partnership with Exobiosphere furthers Cedars-Sinai’s mission to be at the forefront of space biomedicine while deepening our understanding of how organoids develop in microgravity.”

Sharma and his colleagues hope to speed the discovery of therapies that treat medical issues astronauts experience, including bone and muscle loss and heart and immune system degradation. These discoveries could also be applied to terrestrial patients experiencing similar conditions, such as sarcopenia (muscle loss), osteoporosis (bone weakening) and cardiomyopathy (enlargement, stiffening or weakening of the heart muscle).

“Drugs that are used to treat astronauts can also benefit people on Earth, making a potential broader impact for millions of patients,” Sharma said.

Partnering to Solve Challenges of Research in Space

Microgravity offers tremendous opportunities for scientific discovery but also creates challenges that investigators don’t face on Earth. For example, when astronauts open petri dishes in space, the fluid and cells inside drift out.

However, a Cedars-Sinai study co-authored by Sharma and led by Maedeh Mozneb, PhD, from the Sharma Lab, found that in 96-well plates—rows of tiny wells much smaller than petri dishes—surface tension is strong enough to hold the contents in place.

“It was the first time that anybody has ever showed that you can take this piece of affordable hardware that’s commonly used in labs on ground and bring it to space to do cell biology research,” said Sharma, a research professor in the Department of Biomedical Sciences and the Smidt Heart Institute. “In a way, it's democratizing life sciences.”

Building on this discovery, Exobiosphere developed a research platform that automates organoid experimentation in microgravity. The hardware integrates precision liquid handling, environmental control, robotic manipulation and live imaging—capabilities that previously required intensive astronaut intervention.

"This system is designed to remove barriers for scientists," said Kyle Acierno, CEO of Exobiosphere. "By streamlining the complexity of space-based research, we’re enabling our partners to focus on the science itself—delivering data faster, with greater consistency, and at a scale that’s never been possible in orbit."

The unit, about the size of a carry-on suitcase, accommodates six 96-well plates and includes a built-in incubator, microfluidic‑based liquid dispenser, plate reader and robotic arm. While optimized for microgravity, the platform can also enhance lab productivity on Earth.

Exobiosphere’s innovative work earned it a spot in the Cedars-Sinai Accelerator+ program, which invests in startups focused on improving healthcare to help bring their products to market. Cedars-Sinai Technology Ventures also recently made a $1.4 million investment in the company and will provide mentorship from researchers.  

"As an academic medical center committed to innovation, we are thrilled to invest in a company conducting important biosciences research in space while collaborating with our colleagues at the Center for Space Medicine Research," said Nirdesh K. Gupta, PhD, managing partner of Cedars-Sinai Intellectual Property Company. "Our work together exemplifies our dedication to advancing breakthrough technologies that transform healthcare in space and on Earth."

Read more from Discoveries: Space Doctors and Stem Cell Production in Microgravity

“Organoids are three-dimensional clumps of cells—in this case heart or brain cells,” said Arun Sharma, PhD, director of the Cedars-Sinai Center for Space Medicine Research. “To create them, we reprogram skin or blood cells into stem cells and then turn the stem cells into the heart or brain cells that will form the organoids.”

Organoids, which have thus far only been produced on Earth, are less than 1 millimeter in size and are usually too small to see with the naked eye. But they pack a big scientific punch.

“We can create thousands of these organoids in just weeks, allowing us to model disease and test drugs at a scale we would not be able to achieve otherwise,” said Sharma, also a research scientist in the Board of Governors Regenerative Medicine Institute, Smidt Heart Institute, and Cedars-Sinai Cancer, and associate professor of Biomedical Sciences at Cedars-Sinai.

The cells will travel to space as part of NASA’s SpaceX 33rd commercial resupply services mission to the International Space Station, the sixth mission in which Cedars-Sinai has participated. This is the third mission funded via a NASA In-Space Manufacturing Award in partnership with Axiom Space, a Houston-based company developing space infrastructure. Some firsts from previous missions included the introduction of DNA into stem cells in space, use of off-the-shelf terrestrial lab hardware for space biosciences research, and the production of stem cells in space, Sharma said.

Sharma, a specialist in heart biology, uses organoids to study the effects of cancer therapies on the heart. Heart organoids can also be used to test therapies that might improve heart function, and to study various types of heart disease such as congenital heart defects.  

Clive Svendsen, PhD, executive director of the Board of Governors Regenerative Medicine Institute and a collaborator on the mission, studies brain organoids.

“My lab is focused on the study of neurodegenerative diseases such as ALS, Huntington’s disease and Parkinson’s disease, and we use brain organoids as a tool for modeling these diseases,” Svendsen said. “Creating these organoids in space is potentially a step toward accelerating our work and gaining better understanding of these diseases.”

Sharma said there are potential advantages to growing organoids in space.

“On Earth, gravity compresses these organoids, which are three-dimensional spheres,” Sharma said. “In space, gravity is reduced to almost nothing, what we call microgravity, and we believe that organoids will grow better under these conditions. They might develop new blood vessels that we aren’t able to develop on Earth, organize themselves in unique ways, or maybe even harbor different cell types that we can only develop in microgravity.”

Maedeh Mozneb, PhD, associate director of the Center for Space Medicine Research, and Sharma Lab research associate Madelyn Arzt will travel to Florida to prepare the cells for launch.

The stem cells, obtained from the Allen Institute for Cell Science, will be frozen for the trip to space and will travel aboard a SpaceX rocket in a “plate habitat” created by BioServe Space Technologies in Colorado. Once the cells reach the space station, they will be maintained by astronauts, who will change the nutrients that allow the organoids to grow and photograph the organoids using microscopes, Sharma said.

After approximately one month, the organoids will be sent back to Cedars-Sinai investigators for analysis of their size, shape, genetics and other factors. And despite the tiny size of the organoids, Sharma and his team are dreaming big.

“A dream of mine is to have a lab in space that is parallel with the labs that we have here on Earth,” Sharma said. “That would allow us to create organoids and explore biomedical applications like bioprinting of artificial heart, brain and muscle tissues in space in ways that we may not be able to on Earth.”

Next up, the team will be working on experiments funded through a new grant from the National Institutes of Health to explore using microgravity to model accelerated inflammation and aging in organ chip models of the heart, gut, and brain.

Cedars-Sinai Health Sciences University is advancing groundbreaking research and educating future leaders in medicine, biomedical sciences and allied health sciences. Learn more about the university.

May 22—and marked the occasion with a visit from NASA astronaut and microbiologist Kate Rubins, PhD.

“The Center for Space Medicine Research leverages our expertise in academics, research and clinical medicine and builds on a decade of work in the Regenerative Medicine Institute,” said Arun Sharma, PhD, associate professor of Biomedical Sciences at Cedars-Sinai and director of the new research center. “Space biomedicine is a rapidly emerging field, and we are building a solid body of research into what happens to the human body in space and how stem cells behave in microgravity.”

Cedars-Sinai has sent five experiments on missions to the International Space Station, with more planned beginning in late summer. In addition to space experiments, the new center will establish an educational initiative tied to the Cedars-Sinai Master of Science in Regenerative Medicine program, which includes space biomedicine courses, Sharma said.

“As an academic medical center engaged in disease discovery programs, Cedars-Sinai is not limiting its research to the confines of the Earth’s gravitational field,” said Shlomo Melmed, MB, ChB, executive vice president of Medicine and Health Sciences and dean of the Medical Faculty. “The establishment of this new research center is another step in our great journey of scientific discovery, translational medicine and patient care.”

Rubins, who worked with Sharma in 2016 on the first long-duration cell culture experiment in space, kicked off a seminar series devoted to space biomedicine research with a talk titled “The Next Frontier: Biomedical Research in the Second Space Age.”

Rubins earned a bachelor of science in molecular biology from the University of California, San Diego (UCSD), and a PhD in cancer biology from Stanford University Medical School’s Biochemistry, Microbiology and Immunology Departments. Throughout her two flights to the International Space Station, she spent 300 days in space and performed four spacewalks.

“We’re at the beginning of the second space age,” Rubins said. “When you lift the weight of gravity off living systems you open up exciting new pathways for discovery. Microgravity gives us physics that we just cannot buy or build on Earth.”

Rubins also stressed the potential of advances made in space to address medical and environmental issues on Earth—including sources of clean water and air and options for remote health care delivery.

Maedeh Mozneb, PhD, a project scientist in the Sharma Lab at Cedars-Sinai, has been named associate director of the center. Mozneb has been instrumental in characterizing effects of low-Earth orbit on stem cell expansion, transfection, reprogramming and differentiation. Additional faculty members include Clive Svendsen, PhD, executive director of the Board of Governors Regenerative Medicine Institute, Dhruv Sareen, PhD, associate professor of Biomedical Sciences and chief biomanufacturing officer for the Cedars-Sinai Biomanufacturing Center, and Sonja Schrepfer, MD, PhD, research scientist in the Regenerative Medicine Institute.

“The Center for Space Medicine Research is the latest in a series of new projects and growth we have been pursuing on Earth and in orbit,” Svendsen said. “We are excited about this next step and look forward to new discoveries and to helping educate the next generation of space medicine researchers.”

Sharma noted that the timing—and location—are both ideal for a new space medicine endeavor. Southern California is home to the NASA Jet Propulsion Laboratory, SpaceX and enough aerospace startups in Long Beach to earn it the nickname “Space Beach.”

“People don’t always think of L.A. as an aerospace hub,” Sharma said, “but it is becoming that, and Cedars-Sinai is all in.”

Cedars-Sinai Health Sciences University is advancing groundbreaking research and educating future leaders in medicine, biomedical sciences and allied health sciences. Learn more about the university.

Organoids are used to model diseases and test potential treatments. They can be made in a scientific laboratory on Earth, but research suggests the microgravity environment (weightlessness) of space improves organoid function.

Sharma, director of the Cedars-Sinai Shared Resources Laboratory for Advanced Stem Cell Modeling, told reporter Will Stone that his laboratory is focused on the heart and also is working with NASA on stem cell research in space.

“The thing that everybody’s looking for is something that can only be done up there, and you cannot do it down here,” Sharma said. “We and others have shown that certain stem cell populations can proliferate or divide faster in space.”

Sharma told Stone scientists hope to one day be able to develop actual organs in space and use them for transplants.

“I don’t think we’re close yet to fully, perfectly approximating a human heart on Earth from stem cell-derived cells,” he said.

But in the meantime, he added, investigators can gain valuable insights into how cells function without gravity.

“By having better model systems—systems that have, say, blood vessels incorporated into them—we can better approximate how certain drugs would affect the heart,” he told Stone.

Click here to listen to the entire segment from NPR.

By introducing DNA into mature adult cells, scientists can reprogram them into a type of stem cell called induced pluripotent stem cells. They can then turn the cells into other cell types. This process has been used for years to manufacture or replicate large numbers of cells for research and the development of new disease treatments.

Previous studies have found that when grown under microgravity, the near-weightlessness found in space, stem cells function differently. The lack of gravity could speed up cell manufacturing, said Arun Sharma, PhD, research scientist in the Cedars-Sinai Board of Governors Regenerative Medicine Institute, research professor in the Department of Biomedical Sciences and the Smidt Heart Institute and co-senior author of the study.

“Our goal has been to understand and harness those differences to more effectively and efficiently produce stem cells in a way that’s impossible on Earth,” Sharma said. “Cedars-Sinai is now the first to successfully introduce DNA into human induced pluripotent stem cells in space, establishing the foundation for our next step toward large-scale manufacturing of stem cells in space.”

The experiments took place aboard Axiom Mission 2, Axiom Space’s second astronaut mission to the International Space Station.

“We are pleased to be partnering with the Cedars-Sinai team on this NASA-funded in-space manufacturing program, leveraging microgravity to establish production of stem cell therapies,” said Pinar Mesci, PhD, global head of Regenerative Medicine & Disease Modeling at Axiom Space. “This publication is an important step toward demonstration of how human pluripotent stem cells can be cultured, transfected and grown in low-Earth orbit using commercial, off-the-shelf terrestrial hardware that will accelerate research and discovery as well as in-space manufacturing.”

During the mission, cells that had been frozen for transport were thawed and transferred into cell culture dishes by specially trained astronauts. Among them was Rayyanah Barnawi of the Saudi Space Agency, the first Saudi and female astronaut, first Arab woman in space, and a co-author of the study. 

“Among the technical challenges associated with doing this kind of work in space was the challenge of keeping the cells in their dishes,” Sharma said. “On Earth, if we want to change the nutrients in a dish, we simply open the lid. In microgravity, if you open a lid, everything will escape. On this mission, we discovered that the surface tension of the fluid in 96-well plates commonly used in labs was enough to hold the cells in place in microgravity, meaning we didn’t need custom equipment for these experiments.” 

Investigators on Earth, including lead study author and project scientist Maedeh Mozneb, PhD, performed identical experiments so that the two sets of cells could be compared. One surprise from space: The cells arranged themselves into three-dimensional spheres, rather than lying flat in a dish as they would on Earth.

“That was a very exciting surprise,” Sharma said. “We weren’t intending to grow the cells in three dimensions. The cells did that on their own. This makes sense, because in the microgravity found in space, things float around, and the cells floated and arranged themselves into spheres.”

This has made investigators think about the next step in the process of stem cell manufacturing, and how this new discovery might be used. 

“We’ve since completed additional missions directed at making human induced pluripotent stem cells entirely in microgravity,” said Clive Svendsen, PhD, executive director of the Board of Governors Regenerative Medicine Institute, professor of Medicine and Biomedical Sciences at Cedars-Sinai, and co-senior author of the study. “These studies are ongoing and we hope will ultimately advance stem cell technology by providing a unique type of stem cell—one made in space.”

Additional Cedars-Sinai Authors: Madelyn Arzt, Stephany Pohlman, George Lawless

Additional Authors: Pinar Mesci, Dylan MN Martin, Shankini Doraisingam, Sultan Al Neyadi, Rayyanah Barnawi, Ali Al Qarni, Peggy A. Whitson, John Shoffner, Jana Stoudemire, Stefanie Countryman 

Funding: A.S. and C.N.S. are supported by the Board of Governors Regenerative Medicine Institute at Cedars-Sinai and an In-Space Production Award (InSPA) from NASA (NNJ13ZBG001N). A.S. received support from the American Heart Association Career Development Award 856987.  

Read more in Discoveries: Frontiers in Single-Cell Biology

“We will be conducting the entire induced pluripotent stem cell reprogramming process in space, and this is the first time this has been done,” said Arun Sharma, PhD, a stem cell biologist and research scientist with the Board of Governors Regenerative Medicine Institute at Cedars-Sinai.

Induced pluripotent stem cells, or iPSCs, are adult cells that are reprogrammed into a state where they can be turned into many other cell types. Large volumes of iPSCs are needed for research and to create stem-cell-based treatments for disease, and investigators believe that the microgravity environment of space could make it easier to manufacture the cells.

During the mission, funded through a NASA In Space Production Applications Award, astronauts aboard the International Space Station will work with cells supplied by the Allen Institute for Cell Science. They will add the elements that will reprogram the cells into stem cells, and periodically transfer the cells to an imaging system that allows investigators on Earth to check on their development.

“Reprogramming the cells is the first step in the iPSC manufacturing process,” said Clive Svendsen, PhD, executive director of the Board of Governors Regenerative Medicine Institute. “The next stage is expansion, which is the growth and replication of the cells so that we can produce billions of them. We want to know how microgravity affects these processes.”

Lessons learned in space will help determine whether large-scale stem cell manufacturing there is feasible, and also will inform biomanufacturing of stem cells on Earth, Svendsen said.

“This space mission will test stem cell manufacturing on a small scale,” said Dhruv Sareen, PhD, founding director of the Cedars-Sinai Biomanufacturing Center and the iPSC Core Facility. “We will use what we learn through these experiments, and lessons from our previous experiments with automated processes in space, to determine how to scale up and create best manufacturing practices for these cells.”

The astronauts will employ the same reprogramming technique developed and used at Cedars-Sinai.

After approximately one month, preserved samples of the cells from the mission will be returned to Earth for quality testing. If all goes well, a mission planned for next year will see the cells turned into brain and heart cells, Sharma said.

“On Earth, we have challenges growing iPSCs, but what if they grow beautifully in microgravity?” Svendsen said. “And what if cell lines created in space have unique characteristics? These are the big questions. And if in 20 years we're making stem cells in space, these experiments will be the origins of it.”

Cedars-Sinai partners in the mission include Axiom Space and BioServe Space Technologies. Project scientist Maedeh Mozneb, PhD, and research associate Madelyn Arzt are key members of the team from the Sharma Lab.

The mission will launch from NASA’s Kennedy Space Center in Florida, on a Northrop Grumman Cygnus spacecraft perched atop a SpaceX Falcon 9 rocket.

The launch is part of a series of NASA-funded missions in which Sharma, Svendsen and Sareen have played key roles. Sharma has also recently been awarded an International Space Station National Laboratory Igniting Innovation grant to conduct further stem cell experiments in space.

“This grant will build on our existing research into biomanufacturing in space with two additional missions,” Sharma said.

The first mission will focus on the creation of cardiac spheroids in space. Cardiac spheroids are tiny clumps of heart muscle cells and heart blood vessel cells, created from stem cells, that function much the way they do in an actual human heart.

“We want to see if the microgravity environment can facilitate the creation of these spheroids,” Sharma said. “It’s possible we’ll be able to achieve better symmetry in space than we can on Earth, where gravity compresses the spheroids against the dish.”

Following that mission, a second mission, connected to the White House Cancer Moonshot, will involve the use of these spheroids to test the potential heart damage (cardiotoxicity) caused by cancer drugs.

“My lab has conducted experiments using stem cell-derived heart cells to explain why and how cancer drugs can damage the heart,” Sharma said. “We’re hoping that these spheroids, created in space, will give us a better way to screen cancer drugs for cardiotoxicity.”

Learn more on the Cedars-Sinai Blog: Stem Cells in Space