"This means that the cells are not able to respond to a pathogen anymore," she said. "For an astronaut, that means that it will be easier to get sick because their immune system is weakening."
Parallels to stress in war
The cells in the space shuttle experiment were so busy dealing with microgravity that they barely put up a fight against infections, said Marti Jett, director of the Integrative Systems Biology Program at the Medical Command.
These results were very similar to those of a study she and her colleagues conducted a couple of years ago with Army Ranger trainees under battlefield conditions.
"We saw a rather similar thing there," Jett said, "that these young men were so stressed from reduced sleep, their heavy exercise, their activities, that their immune cells simply did not respond very well, when ex-vivo [outside the body] exposed the cells to a variety of pathogens."
This weakened immune response echoed the results with the space shuttle samples. But the Atlantis experiment revealed other effects.
Researchers found the reduced gravity also activated certain genes in the human tissue involved with rheumatoid arthritis and tumor growth, raising additional health concerns for human space flight.
Could lead to new therapies
Identifying which gene molecules were responsible for the weakened immune response offers hope for therapeutic strategies, both in space and on Earth.
最新
2013-11-25
2013-11-25
2013-11-25
2013-11-25
2013-11-25
2013-11-25