Scientists have established that extended spaceflight can lead to suppression of the body's immune system, making astronauts more susceptible to a range of illnesses--but ‘why' and ‘how' remains open for debate.
Dylan Ludwick '15 and Sejiro Littleton '15 seized the opportunity to explore these questions in an independent study course with Associate Professor of Biology Sophia Sarafova, and ultimately to publish their findings.
Ludwick and Littleton previously had taken an immunology class and a "Case Studies in Immune System Dysfunction" seminar with Sarafova, which piqued their interest in the subject matter.
"Also, I've always been fascinated with the cosmos, so when Sejiro mentioned a NASA article about astronauts and T cells, I knew it was a topic worth pursuing," Ludwick recalled.
They enlisted Sarafova as project adviser and, for an insider's view of space travel and health, they sought out Davidson's closest NASA connection--astronaut Tom Marshburn '82.
Marshburn, who has traveled into space twice, confirmed that the effects of a zero gravity environment are felt profoundly and immediately.
"Weightlessness makes you feel congested. Fluids rise up in your body, and the nervous system doesn't know how to interpret the environment. A lot of things happen on a cellular level in space, and bacteria become more virulent," he noted. "There is a lot of fascinating research to be done about this."
On Earth, a cough or sneeze can propel infectious particles from 3 to 6 ft. away before they fall out of the air thanks to gravity. In space, not so-they continue to float, landing on any and all available surfaces within the spacecraft. Not only do these agents of contagion get a longer shelf life in space, but they also have more opportunities to flourish in an environment in which pathogens grow stronger and more resistant to antimicrobial agents and the human immune system becomes slower and less effective.
Ludwick and Littleton spent the spring 2015 semester conducting a literature review of relevant research, and then assimilated the information into a review article that described their findings.
The project proved to be demanding, given the sheer volume of information available on the topic and the discrepancies they encountered among the findings of the various studies.
"We have more than 60 references in our bibliography," said Ludwick. "Many articles left us with more questions than answers. Sorting through the information to reveal a clearer picture of the situation was challenging."
But their persistence paid off. Their paper, titled "Altered Immune Function in Space: Implications of a Gravity Sensitive Cytoskeleton," has been published in the annual student research compendium Explorations: The Journal of Undergraduate Research and Creative Activities for the State of North Carolina.
Their conclusion? "The data suggests that the cytoskeleton and some of its regulatory elements are affected by microgravity, and in turn alter the ability of immune cells to function," Littleton said.
The cytoskeleton plays an important role in cellular functioning, and Littleton and Ludwick's findings suggest immune cells may be compromised in a zero gravity environment.
Sarafova was impressed with their work, and the final product.
"Research allows you to follow your passion," she said. "It makes all the difference if you're passionate about your subject. You delve more in depth, ask more relevant questions, and are more motivated to find answers."
Ludwick agreed. "Even after reading countless papers and feeling the looming pressure of finals, it was difficult to view what we were doing as ‘work'. Both of us felt a genuine pursuit of knowledge that made it easy to immerse ourselves in the research. I think that's the best kind of science."
Littleton, a native of Spruce Pine, North Carolina, currently serves as Sarafova's lab technician and hopes to earn a doctoral degree in a program related to immunology, bioinformatics or astrobiology. Ludwick, a native of Philadelphia, is preparing for a doctoral program in biophysics.