Rocket re-usability, the Lunar Gateway Station, the Artemis program, a potential research station on the Moon and a future crewed Mars mission. The future of human space exploration unavoidably points towards a higher exposure to deeper space for longer periods of time, definitely involving an increasing number of astronauts. The scientific community is well-aware of the detrimental effects that low Earth orbit may have on muscles and bones, yet mitigation is addressable. Nevertheless, more subtle changes at cellular and molecular levels are taking place in the backstage. These changes are not immediately noticed by astronauts nor researchers, and we are not aware of the extent and consequences that they may have in the long term. Such is the case for the immune response. When it works, the immune system provides powerful, targeted responses that not only are able to face virtually every possible pathogen, but also memorizes it. However, exposing our biological shields to radiation, microgravity and stress submits it to a foreign environment that seems to threaten its fierce responses.
To understand the potential effects of spaceflight in the astronaut’s immune response it is first necessary to understand the basic principles of immunity, and so, this talk includes a simple and friendly introduction to the immune system that requires no previous knowledge of any sort.