Zero-G and Immune System.

A new study was found that weightlessness is stressful on the human organs that create immune cells. The study was performed on mice that were stimulated in zero-gravity. This showed that a protein, osteopontin (OPN), a stress hormone is involved with the waste of the spleen and thymus organs. These are the organs that create white blood cells that are able to battle infections. Without the correct amount of white blood cells, a human is at threat for disease, viruses, and bacteria. Osteopontin signals cells for survival and to stay on the offensive during injury and stress, doctors think that it also suppresses the immune system during this time. This new study can lead to research on cutting down the risk of getting sick in space on long space flights.