Spaceflight effects on T lymphocyte distribution, function and gene expression

• Published in: Journal of applied physiology (1985) 2009-01, Vol.106 (1), p.194-202
• Main Authors: Gridley, Daila S, Slater, James M, Luo-Owen, Xian, Rizvi, Asma, Chapes, Stephen K, Stodieck, Louis S, Ferguson, Virginia L, Pecaut, Michael J
• Format: Article
• Language: English
• Subjects: Animals; B-Lymphocytes - immunology; Biological and medical sciences; Cytokines; Cytokines - genetics; Cytokines - metabolism; Deoxyribonucleic acid; DNA; DNA Replication; Female; Flow Cytometry; Fundamental and applied biological sciences. Psychology; Gene expression; Gene Expression Profiling; Gene Expression Regulation, Neoplastic; Immune system; Killer Cells, Natural - immunology; Lymphocyte Activation - genetics; Lymphocyte Count; Lymphocytes; Mice; Mice, Inbred C57BL; Physiology; Rodents; Space exploration; Space Flight; Spleen - immunology; T-Lymphocytes - immunology; Thymus Gland - immunology; Time Factors; Weightlessness
• ISSN: 8750-7587; 1522-1601
• DOI: 10.1152/japplphysiol.91126.2008

1 Department of Radiation Medicine, Molecular Radiation Biology Laboratories and 2 Department of Basic Sciences, Division of Microbiology and Biochemistry, Loma Linda University and Medical Center, Loma Linda, California; 3 Division of Biology, Kansas State University, Manhattan, Kansas; and 4 Department of Aerospace Engineering, BioServe Space Technologies, University of Colorado, Boulder, Colorado Submitted 21 August 2008 ; accepted in final form 31 October 2008 The immune system is highly sensitive to stressors present during spaceflight. The major emphasis of this study was on the T lymphocytes in C57BL/6NTac mice after return from a 13-day space shuttle mission (STS-118). Spleens and thymuses from flight animals (FLT) and ground controls similarly housed in animal enclosure modules (AEM) were evaluated within 3–6 h after landing. Phytohemagglutinin-induced splenocyte DNA synthesis was significantly reduced in FLT mice when based on both counts per minute and stimulation indexes ( P < 0.05). Flow cytometry showed that CD3 + T and CD19 + B cell counts were low in spleens from the FLT group, whereas the number of NK1.1 + natural killer (NK) cells was increased ( P < 0.01 for all three populations vs. AEM). The numerical changes resulted in a low percentage of T cells and high percentage of NK cells in FLT animals ( P < 0.05). After activation of spleen cells with anti-CD3 monoclonal antibody, interleukin-2 (IL-2) was decreased, but IL-10, interferon- , and macrophage inflammatory protein-1 were increased in FLT mice ( P < 0.05). Analysis of cancer-related genes in the thymus showed that the expression of 30 of 84 genes was significantly affected by flight ( P < 0.05). Genes that differed from AEM controls by at least 1.5-fold were Birc5, Figf, Grb2 , and Tert (upregulated) and Fos, Ifnb1, Itgb3, Mmp9, Myc, Pdgfb, S100a4, Thbs , and Tnf (downregulated). Collectively, the data show that T cell distribution, function, and gene expression are significantly modified shortly after return from the spaceflight environment. cytokines; cancer; immune system; leukocytes Address for reprint requests and other correspondence: D. S. Gridley, Chan Shun Pavilion, Rm. A-1010, 11175 Campus St., Loma Linda Univ., Loma Linda, CA 92354 (e-mail: dgridley{at}dominion.llumc.edu )