I’m really only half joking when I say I want to be an astronaut when I grow up. When experiments aren’t going well, my friends and I discuss the various ways in which we could convince the International Space Station (ISS) that we’re Star Fleet material. Since the relaxation of military and flight time requirements, we’ve been looking forward to stepping off this chaos of hard clay to wander darkling in the eternal space. Romance aside, the effects of space travel on health and the unique physiological and psychological conditions of long-range space travel really do interest a growing number of research scientists, myself included. How exciting, then, to hear from my friend Rishi that CASIS (the Center for the Advancement of Science in Space) have issued a request for proposals looking into the effects of microgravity on stem cells. I’m a biologist; surely I work on stem cells. Well, not quite. I work on the immune system, the cells of which do indeed derive from stem cells, but my interests lie much further down the developmental line. I study how a fully mature immune system works to protect the body against infection and how vaccines use the same machinery to protect against diseases before we encounter them. To me, this has obvious applications for interplanetary space exploration.
A recent publication in the Journal of Clinical Immunology1 shows altered immune function following space flight. Levels of inflammation-driving molecules in the blood go up, but specific responses to viruses by T cells go down. Is this a Big Deal? Let’s assume that people aren’t allowed into space if they have a serious illness and that the vacuum of space is clean enough that disease-causing bugs are unlikely to get on board a spaceship and make everyone evolve backwards or suddenly challenge the entire crew to a duel. Does it matter if the immune system is depressed in space? Well, one of the observations highlighted in the paper is that virus-specific responses are reduced. This might not be a problem if we weren’t all riddled with a large number of viruses that are only kept in check by constant immune surveillance. Almost everyone is infected with JC virus, Cytomegalovirus, Epstein-Barr virus, Varicella-Zoster virus, and several other strains of common herpesviruses. Many diseases, including shingles, are associated with a drop in T cell responses and can be severely debilitating. Surely we need someone doing research up there to see how immune responses to these long-term resident viruses change. An outbreak of shingles during a long voyage may not make compelling television, but could severely compromise an astronaut’s ability to function when far from access to antiviral drugs and pain medication. Clearly (if perhaps tinged with a little bias), research into the immune system is much more directly applicable to survival in space than stem cell research, which is still very much in the early stages.
As Commander Chris Hadfield showed so wonderfully, there are many and varied experiments that can be conducted in space that will have an impact on future astronauts. Part of me is tempted to speculate as to why CASIS have limited their remit to stem cells. Is it just because they’re cool and in the news a lot these days? Have the people controlling the purse strings been sweet-talked by a lobbyist with stem cell leanings? Or was this really the result of a long and in-depth study section on the biological priorities of extraterrestrial research? The cynic in me is clamouring for a rant about the whims of science policy but, since I know so little about the process, I should probably save my energies for more productive tasks. Like thinking of ways to convince CASIS that I work on stem cells.
1) Crucian et al (2013). Immune system dyregulation occurs during short duration spaceflight on board the space shuttle. Journal of Clinical Immunology 33 (2): 456-465.
Editor's Note: The author wishes me to express that she would prefer that CASIS used the correct spelling of 'Centre' in its name. Unfortunately, there was not time for the Center to make this official name change prior to this article going to press. Watch this space for updates.