1. Microgravity Inhibits Resting T Cell Immunity in an Exposure Time-Dependent Manner
- Author
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Yong Zhao, Meifu Feng, Chongzhen Wang, and Haiying Luo
- Subjects
CD4-Positive T-Lymphocytes ,Male ,Time Factors ,T cell ,proliferation ,T-Lymphocytes ,T cells ,chemical and pharmacologic phenomena ,Apoptosis ,Biology ,CD8-Positive T-Lymphocytes ,Lymphocyte Activation ,Flow cytometry ,spaceflight ,Mice ,Immune system ,T-Lymphocyte Subsets ,medicine ,Concanavalin A ,Animals ,IL-2 receptor ,Immune response ,Cell Proliferation ,medicine.diagnostic_test ,Cell growth ,Weightlessness ,General Medicine ,microgravity ,Cell biology ,Mice, Inbred C57BL ,medicine.anatomical_structure ,biology.protein ,Cytokines ,Cytokine secretion ,CD8 ,Research Paper - Abstract
Background: Decline immune function is well documented after spaceflights. Microgravity is one of the key factors directly suppressing the function of immune system. Though T cell immune response was inhibited by microgravity, it is not clearly whether activation would be inhibited after a pre-exposure of microgravity on T lymphocytes at the resting state. Methods: We herein investigated the response ability of resting CD4+ and CD8+ T cells experiencing pre-exposure of modeled microgravity (MMg) for 0, 8, 16 and 24 hrs to concanavalin A (ConA) stimulation. The phenotypes and subsets of immune cells were determined by flow cytometry. Results: Both CD4+ and CD8+ T cells with an MMg pre-exposure exhibited decreased expressions of activation-markers including CD25, CD69 and CD71, inflammatory cytokine secretion and cell proliferation in response to ConA compared with T cells with 1g controls in an MMg exposure time- dependent manner. Moreover, short term MMg treatment caused more severe decreased proliferation in CD4+ T cells than in CD8+ T cells. Conclusions: MMg can directly impact on resting T cell subsets. CD4+ T cells were more sensitive to the microgravity inhibition than CD8+ T cells in respect of cell proliferation. These results offered new insights for the MMg-caused T cell functional defects.
- Published
- 2013