According to new research led by Jean-Pol Frippiat of Nancy-University (Vandœuvre-lès-Nancy, France), space travel may compromise antibody production. Apparently, zero gravity conditions can decrease the variability that makes antibodies so powerful.
Our immune systems rely heavily on the fast diversity of our antibodies to attack any foreign invader we might encounter. In addition to the variability that is built into the manufacture of antibodies (which can be put together in a great many combinations), antibody genes also mutate at extremely high rates. Now it seems that the hypermutation of antibody genes is decreased during extended periods at zero gravity.
The researchers compared three groups of the amphibians Pleurodeles waltl (known to produce antibodies the same way that humans do). One group of the newts was immunized on Earth, one in space, and one not at all. The space group showed a lower frequency of mutation than the Earth-bound group. This could mean that human space travelers will have a harder time fighting off infections. On the other hand, astronauts will probably only have to contend with their own germs anyway, not new ones.