title: Genetic models in applied physiology: selected contribution: effects of spaceflight on immunity in the C57BL/6 mouse. II. Activation, cytokines, erythrocytes, and platelets.
abstract: This portion of the study quantified the effects of a 12-day space shuttle mission (Space Transport System-108/UF-1) on body and lymphoid organ masses, activation marker expression, cytokine secretion, and erythrocyte and thrombocyte characteristics in C57BL/6 mice. Animals in flight (Flt group) had 10-12% lower body mass compared with ground controls housed either in animal enclosure modules or under standard vivarium conditions (P < 0.001) and the smallest thymus and spleen masses. Percentages of CD25(+) lymphocytes, CD3(+)/CD25(+) T cells, and NK1.1(+)/CD25(+) natural killer cells from Flt mice were higher compared with both controls (P < 0.05). In contrast, CD71 expression was depressed in the Flt and animal enclosure module control mice compared with vivarium control animals (P < 0.001). Secretion of interferon-gamma, IL-2, and IL-4, but not tumor necrosis factor-alpha and IL-5, by splenocytes from Flt mice was decreased relative to either one or both ground controls (P < 0.05). Flt mice also had high red blood cell and thrombocyte counts compared with both sets of controls; low red blood cell volume and distribution width, percentage of reticulocytes, and platelet volume were also noted (P < 0.05) and were consistent with dehydration. These data indicate that relatively short exposure to the spaceflight environment can induce profound changes that may become significant during long-term space missions.
authors.affiliation: Department of Radiation Medicine, Division of Microbiology and Molecular Genetics, Loma Linda University and Medical Center, Loma Linda, California 92354, USA.
authors.forename: Daila S
authors.initials: DS
authors.lastname: Gridley
authors.forename: Gregory A
authors.initials: GA
authors.lastname: Nelson
authors.forename: Luanne L
authors.initials: LL
authors.lastname: Peters
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Kostenuik
authors.forename: Ted A
authors.initials: TA
authors.lastname: Bateman
authors.forename: Sean
authors.initials: S
authors.lastname: Morony
authors.forename: Louis S
authors.initials: LS
authors.lastname: Stodieck
authors.forename: David L
authors.initials: DL
authors.lastname: Lacey
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Simske
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Pecaut
mesh_terms: D000818:Animals; D015415:Biomarkers; D001792:Blood Platelets / Q000502:physiology*; D001835:Body Weight / Q000502:physiology; D002470:Cell Survival / Q000502:physiology; D016207:Cytokines / Q000096:biosynthesis*; D004326:Drinking / Q000502:physiology; D004435:Eating / Q000502:physiology; D004906:Erythrocyte Count; D004912:Erythrocytes / Q000502:physiology*; D005260:Female; D007109:Immunity / Q000502:physiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D009929:Organ Size / Q000502:physiology; D010976:Platelet Count; D013026:Space Flight; D013154:Spleen / Q000166:cytology
chemical_list: D015415:Biomarkers; D016207:Cytokines