Mouse femur LC-MSMS upon weightlessness

Bone loss and immune dysregulation are among the main adverse outcomes of spaceflight challenging astronaut’s health and safety. However, consequences on B cell development and responses are still under-investigated. Up to now, most studies addressing these questions were performed using an amphibian species. Consequently, we used advanced proteomics analysis of femur bone and marrow of mice flown for one month on board the BION-M1 biosatellite, to determine whether extreme conditions encountered during a real spaceflight affect B cell development in mice and to examine reversibility of the effects upon return to Earth. Our data revealed that adverse effects on B lymphopoiesis were more marked one week after landing and that this phenomenon was associated with a 41% reduction of B cells in the spleen. Thus, the effects of spaceflight persisted during at least one week after landing. These reductions may contribute to explain increased susceptibility to infection even if we confirmed that animals were able to mount a humoral immune response.

骨丢失与免疫失调是航天飞行引发的主要不良结局之一，严重威胁航天员的健康与安全。然而，目前针对航天对B细胞发育及功能的影响的研究仍相对不足。迄今为止，相关领域的多数研究均以两栖类动物为实验模型开展。因此，本研究借助搭载于BION-M1生物卫星、在轨飞行1个月的小鼠股骨及骨髓样本的先进蛋白质组学分析，旨在探究真实航天飞行中的极端环境是否会影响小鼠B细胞发育，并考察返回地球后该影响的可逆性。研究数据显示，着陆后1周时，对B淋巴细胞生成的不良影响更为显著，且该现象与脾脏中B细胞数量减少41%密切相关。由此可见，航天飞行的影响至少在着陆后1周内仍持续存在。尽管本研究已证实小鼠仍可诱发体液免疫应答，但上述B细胞数量的减少或可部分解释感染易感性升高的原因。