Human cellular immune responsiveness following space flight
Taylor, G.R.; Dardano, J.R.
Kosmicheskaia Biologiia i Aviakosmicheskaia Meditsina 18(1): 74-80
1984
ISSN/ISBN: 0321-5040 PMID: 6700190 Document Number: 223861
Peripheral circulating lymphocytes were separated from astronaut blood samples 3 times before and 2 times after the first four US Space Shuttle flights. The ability of the in vitro T lymphocytes to respond to phytohemagglutinin by blastogenesis was found to be reduced for each crewmember following spaceflight. In addition, the astronauts experienced a postflight increase in neutrophils and a decrease in eosinophils. These postflight changes in leukocytes are shown to increase with subjectively evaluated increases in the incidence of inflight stress, indicating that stress, and not hypogravity, is likely to be the major affector of the noted change.