Fruit Flies Offering Clues About An Astronaut’s Immune System

Lee Rannals for – Your Universe Online
Researchers, publishing a paper in the journal PLOS ONE, say fruit fly studies could give insight into how microgravity impacts an astronaut’s immune system.
A team from the University of California at Davis and the University of Central Florida studied how fruit flies handle being in microgravity. Fruit flies have a similar immune system to that of humans and other mammals, so it makes them a great subject to study the impact of weightlessness on our immune system.
Zero gravity can have negative impacts on muscle, bone mass and the immune system, but so far scientists have been puzzled as to why. The latest study shows one way in which the immune system may suffer from a microgravity environment.
The team bred flies in space while aboard the Space Shuttle Discovery in 2006 and waited as the flies developed into adults during the 12-day mission. Once the mission landed scientists retrieved the flies and subsequently found they were more apt to get fungal infections.
“Our study showed that a biochemical pathway needed to fight fungal infections is seriously compromised in the flies after space flight,” Laurence Von Kalm, a UCF biologist who worked on the study, said in a statement. “More work will be needed to determine if similar effects occur in humans, but this gives us some clues. Getting a better understanding is particularly important, especially as we look to engage in long-term missions such as interplanetary space flights.”
The researchers also found that the system the flies use for detecting and defending against fungal infection was deactivated. However, another system used to defend against bacterial infections did not suffer during the space flight.
“We speculate on possible linkage between functional Toll signaling and the heat shock chaperone system. Our major findings are that hypergravity and spaceflight have opposing effects, and that spaceflight produces stress-related transcriptional responses and results in a specific inability to mount a Toll-mediated infection response,” the team wrote in the journal.
Understanding the impacts of microgravity on our body is crucial to knowing what astronauts should expect for long-duration missions, such as traveling to Mars or an asteroid. The researchers hope to continue this study by bringing the experiment to the International Space Station.