Immune dysregulation is among the main adverse outcomes of spaceflight. Despite the crucial role of the antibody repertoire in host protection, the effects of spaceflight on the human antibody repertoire are unknown. Consequently, using high‐throughput sequencing, we examined the IgM repertoire of five cosmonauts 25 days before launch, after 64 ± 11 and 129 ± 20 days spent on the International Space Station (ISS), and at 1, 7, and 30 days after landing. This is the first study of this kind in humans. Our data revealed that the IgM repertoire of the cosmonauts was different from that of control subjects (n = 4) prior to launch and that two out the five analyzed cosmonauts presented significant changes in their IgM repertoire during the mission. These modifications persisted up to 30 days after landing, likely affected the specificities of IgM binding sites, correlated with changes in the V(D)J recombination process responsible for creating antibody genes, and coincided with a higher stress response. These data confirm that the immune system of approximately half of the astronauts who spent 6 months on the ISS is sensitive to spaceflight conditions, and reveal individual responses indicating that personalized approaches should be implemented during future deep‐space exploration missions that will be of unprecedented durations.

中文翻译：

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响应长期太空飞行的人类 IgM 库的可塑性

免疫失调是航天飞行的主要不良后果之一。尽管抗体库在宿主保护中起着至关重要的作用，但太空飞行对人类抗体库的影响尚不清楚。因此，使用高通量测序，我们在发射前 25 天、在国际空间站 (ISS) 度过 64 ± 11 和 129 ± 20 天后以及发射后 1、7 和 30 天检查了五名宇航员的 IgM 库。降落。这是人类首次进行此类研究。我们的数据显示，宇航员的 IgM 曲目在发射前与对照受试者（n = 4）不同，五名分析的宇航员中有两人在任务期间的 IgM 曲目发生了重大变化。这些修改在着陆后持续了 30 天，可能影响 IgM 结合位点的特异性，与负责产生抗体基因的 V(D)J 重组过程的变化相关，并与更高的应激反应相吻合。这些数据证实，在国际空间站上呆了 6 个月的宇航员中，约有一半的免疫系统对太空飞行条件很敏感，并揭示了个人反应，表明在未来的深空探索任务中应该实施个性化的方法，这将是前所未有的持续时间.