title: Antibody responses to bacteriophage phi X-174 in human subjects exposed to the antarctic winter-over model of spaceflight.
abstract: BACKGROUND
  It has been proposed that exposure to long-term spaceflight conditions (stress, isolation, sleep disruption, containment, microbial contamination, and solar radiation) or to ground-based models of spaceflight will alter human immune responses, but specific antibody responses have not been fully evaluated.
  
  
  OBJECTIVE
  We sought to determine whether exposure to the 8-month Antarctic winter-over model of spaceflight would alter human antibody responses.
  
  
  METHODS
  During the 1999 Australian National Antarctic Research Expeditions, 11 adult study subjects at Casey, Antarctica, and 7 control subjects at Macquarie Island, sub-Antarctica, received primary and secondary immunizations with the T cell-dependent neoantigen bacteriophage phi X-174. Periodic plasma samples were analyzed for specific antibody function.
  
  
  RESULTS
  All of the subjects from Casey, Antarctica, cleared bacteriophage phi X-174 normally by 1 week after primary immunization, and all had normal primary and secondary antibody responses, including immunologic memory amplification and switch from IgM to IgG antibody production. One subject showed a high normal pattern, and one subject had a low normal pattern. The control subjects from Macquarie Island also had normal immune responses to bacteriophage phi X-174.
  
  
  CONCLUSIONS
  These data do not support the hypothesis that de novo specific antibody responses of subjects become defective during the conditions of the Antarctic winter-over. Because the Antarctic winter-over model of spaceflight lacks the important factors of microgravity and solar radiation, caution must be used in interpreting these data to anticipate normal antibody responses in long-term spaceflight.
authors.affiliation: Baylor College of Medicine, Houston, Texas, USA.
authors.forename: W T
authors.initials: WT
authors.lastname: Shearer
authors.forename: D J
authors.initials: DJ
authors.lastname: Lugg
authors.forename: H M
authors.initials: HM
authors.lastname: Rosenblatt
authors.forename: P M
authors.initials: PM
authors.lastname: Nickolls
authors.forename: R M
authors.initials: RM
authors.lastname: Sharp
authors.forename: J M
authors.initials: JM
authors.lastname: Reuben
authors.forename: H D
authors.initials: HD
authors.lastname: Ochs
mesh_terms: D000328:Adult; D000864:Antarctic Regions / Q000453:epidemiology; D000914:Antibodies, Viral / Q000276:immunology; D000917:Antibody Formation; D000956:Antigens, Viral / Q000276:immunology; D001435:Bacteriophages / Q000276:immunology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012621:Seasons; D013026:Space Flight
chemical_list: D000914:Antibodies, Viral; D000956:Antigens, Viral