Effects of spaceflight on innate immune function and antioxidant gene expression

J Appl Physiol (1985). 2009 Jun;106(6):1935-42. doi: 10.1152/japplphysiol.91361.2008. Epub 2009 Apr 2.


Spaceflight conditions have a significant impact on a number of physiological functions due to psychological stress, radiation, and reduced gravity. To explore the effect of the flight environment on immunity, C57BL/6NTac mice were flown on a 13-day space shuttle mission (STS-118). In response to flight, animals had a reduction in liver, spleen, and thymus masses compared with ground (GRD) controls (P < 0.005). Splenic lymphocyte, monocyte/macrophage, and granulocyte counts were significantly reduced in the flight (FLT) mice (P < 0.05). Although spontaneous blastogenesis of splenocytes in FLT mice was increased, response to lipopolysaccharide (LPS), a B-cell mitogen derived from Escherichia coli, was decreased compared with GRD mice (P < 0.05). Secretion of IL-6 and IL-10, but not TNF-alpha, by LPS-stimulated splenocytes was increased in FLT mice (P < 0.05). Finally, many of the genes responsible for scavenging reactive oxygen species were upregulated after flight. These data indicate that exposure to the spaceflight environment can increase anti-inflammatory mechanisms and change the ex vivo response to LPS, a bacterial product associated with septic shock and a prominent Th1 response.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Cytokines / metabolism
  • Female
  • Gene Expression*
  • Immunity / physiology*
  • Leukocyte Count
  • Lipopolysaccharides / pharmacology
  • Liver / pathology
  • Lymphocyte Activation / immunology
  • Lymphocyte Count
  • Mice
  • Myoglobin / genetics*
  • Oligonucleotide Array Sequence Analysis
  • Organ Size
  • Oxidative Stress / genetics*
  • RNA, Messenger / metabolism
  • Space Flight*
  • Spleen / drug effects
  • Spleen / metabolism
  • Spleen / pathology
  • Thymus Gland / pathology
  • Up-Regulation


  • Cytokines
  • Lipopolysaccharides
  • Myoglobin
  • RNA, Messenger