Our immune system in space

With the arrival of a new crew on the International Space Station, astronauts will be relieved to know that they will not have to worry about an important aspect of their compromised immune system. Researchers know a lot about the skeletal and muscular health of astronauts during spaceflight and when they return to Earth, but much less is known about how spaceflight affects immunity. Until now, it was generally thought that spaceflight had a detrimental impact on all aspects of the immune system.

"Long-term orbital flights are associated with increased levels of psychological stress, acute and chronic exposure to space radiation and microgravity-induced changes, all known to have a negative impact on the immune system. However, the effects of spaceflight on the immunity of B lymphocytes – a major arm of the immune system – remained unclear, "said William Spielmann, assistant professor at the LSU School of Kinesiology and co-author of a new study on the effects of spaceflight in a large part of the immune system.

The successful implementation of exploration missions on Mars or other near-Earth objects requires a better understanding of the impact of long-duration spaceflight on the immune system in order evaluate the risks of adverse health events associated with immune dysregulation for the crew.

To date, due to logistical constraints imposed by spaceflight, the majority of space immunology activities have been conducted during short-duration missions or by comparing measurements of immune function before and after flight. Last week, John Campbell of the Department of Health of the University of Bath, Spielmann, published the results of a long-term flight study aimed at shedding light on any alteration in lymphocyte function B humans in astronauts living on the International Space Station (ISS). 6 months.

B cells are an essential type of white blood cell responsible for the production of antibodies to target harmful pathogens. Optimal immunity of B cells is crucial for long-term protection against disease-causing bacteria and viruses, and is the cornerstone of vaccine efficacy.

"This is the first study to comprehensively demonstrate that long-duration spaceflight by human astronauts has limited effects on B cell frequency and antibody production," he said. Campbell.

Blood samples were taken from astronauts before, during and after 6 months of life on the ISS. The results suggest that the immune competence of B cells was not affected by the time spent on the ISS. These findings could support the use of vaccine-based flight countermeasures to protect astronauts from immune dysregulation and latent symptomatic viral reactivations known to occur in long-duration missions, such as subsequent displacements to Mars.

This study provides new information on the immunity of B cells during a six-month mission in the ISS. The team behind it suggests that future studies are still needed to ensure that the ability of astronauts to produce functional antibodies will remain unchanged during longer missions.

This article has been republished from documents provided by Louisiana State University. Note: Content may have changed for length and content. For more information, please contact the cited source.

Reference
Homeostasis of B cells is maintained during long-term space flight. Guillaume Spielmann et al. Journal of Applied Physiology, November 29, 2018, https://doi.org/10.1152/japplphysiol.00789.2018.