I don't think there's any doubt that NK-cell function is decreasing in the spaceflight environment when analyzed in a cell culture system. Richard Simpson More Quotes by Richard Simpson More Quotes From Richard Simpson The next question would be, how do we mitigate these effects ? How do we prevent the immune system from declining during space travel ? in order to do that, you have to first figure out what's causing the decline : Is it stress ? Is it microgravity ? Is it radiation ? Is it a plethora of things ? When we figure that out, we can try to find ways to directly target those factors and mitigate them. Richard Simpson top-news What NASA and other space agencies are concerned about is whether or not the immune system is going to be compromised during very prolonged spaceflight missions, what clinical risks are there to the astronauts during these missions when theyre exposed to things like microgravity, radiation and isolation stress? Could it be catastrophic to the level that the astronaut wouldnt be able to complete the mission? Richard Simpson science People have this fear in the back of their heads about playing it too loose, and spending too much time down here, whenever there's a 'Canada Night' gathering, it's the No.1 topic of conversation. Richard Simpson money