Photo: Frank Rubio/NASA/ZumaWire/IMAGO / Courtesy
The results of a new investigation show the damage of the weightlessness of space in the human body: according to the findings, the genes of the white blood cells that are so important for the immune system, decrease their activity under such circumstances.
In the study, published in the scientific journal “Frontiers of Immunology,” 14 astronauts participated who spent between four and a half and six and a half months aboard the International Space Station (ISS for its acronym in English). Blood samples taken before, during and after their stay in space showed how genetic activity in the so-called leukocytes changed: it decreased rapidly when the astronauts reached space and quickly returned to normal after their return to Earth.
The results shed light on why astronauts are more susceptible to infection during flight and show how the body is weakened in space to fight pathogens and disease. “Weakened immunity increases the risk of infectious diseases and limits astronauts’ ability to perform their demanding work in space,” says Odette Laneuvielle, a molecular biologist at the University of Ottawa and lead author of the study.
Genes are less able to perform their normal defensive function
Leukocytes are produced in the bone marrow and travel through the bloodstream and tissues. Once they detect invaders such as viruses or bacteria, they produce antibody proteins to fight the pathogen. Certain genes control the release of these proteins.
According to the study, the presence of 247 genes in white blood cells was about a third lower than normal when astronauts were in space. This means that they could no longer perform their immune defense functions as usual. In general, the genes returned to their normal behavior about a month after returning to Earth.
Researchers have previously documented that astronauts in space suffer from immune system dysfunctions.. For example, astronauts have been shown to excrete more viral particles in their biological fluids, such as saliva and urine, making it easier to spread pathogens to other immunocompromised astronauts.
However, according to the study authors, until now the exact mechanisms of this immune system malfunction were unknown.
E.E. (Spiegel, Reuters)