Effect of spaceflight on ability of monocytes to respond to endotoxins of gram-negative bacteria
Effect of spaceflight on ability of monocytes to respond to endotoxins of gram-negative bacteria
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DOI：
10.1128/cvi.00065-08
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发表时间：
2008-10-01
影响因子：
--
通讯作者：
Pierson, Duane L.
中科院分区：
文献类型：
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作者：
Kaur, Indreshpal;Simons, Elizabeth R.;Pierson, Duane L.
宇航员在航天飞机和国际空间站上相对拥挤、狭窄的环境中生活和工作。他们经历了一系列独特的压力源，导致许多免疫反应减弱。这项研究调查了航天飞机机组成员的单核细胞对感染期间可能遇到的革兰氏阴性内毒素的反应能力。发射前10天、着陆后3至4小时和着陆后15天，从20名机组人员和15名对照受试者身上采集了血液样本，并在着陆后6至12个月的年度体检期间采集了机组人员的血液样本。当受到革兰氏阴性内毒素的攻击时，与对照受试者相比，在所有三个时间点收集的机组成员的单核细胞产生的白细胞介素 6 (IL-6) 和 IL-1 beta 水平较低，而 IL-1ra 和 IL-8 水平较高。通过测量细胞内细胞因子阳性的细胞数量来评估细胞因子。着陆后 6 至 12 个月，这些值恢复正常，但 IL-1ra 除外，该值仍比对照组高（五至六倍）。在所有时间点，这种现象都伴随着船员单核细胞上 Toll 样受体 4 表达的增加和 CD14 表达的减少。着陆后3至4小时和15天，机组人员血浆中脂多糖结合蛋白的水平也有所增加。这项研究表明，航天相关因素（飞行中和飞行前）调节单核细胞对革兰氏阴性内毒素的反应。
Astronauts live and work in relatively crowded, confined environments on the Space Shuttle and the International Space Station. They experience a unique set of stressors that contribute to a diminishment of many immune responses. This study investigated the ability of the shuttle crew members' monocytes to respond to gram-negative endotoxin that they could encounter during infections. Blood specimens were collected from 20 crew members and 15 control subjects 10 days before launch, 3 to 4 h after landing, and 15 days after landing and from crew members during their annual medical examination at 6 to 12 months after landing. When challenged with gram-negative endotoxin, the crew member's monocytes collected at all three time points produced lower levels of interleukin-6 (IL-6) and IL-1 beta and higher levels of IL-1ra and IL-8 compared to those of control subjects. Cytokines were assessed by measuring the number of cells positive for intracellular cytokines. These values returned to normal 6 to 12 months after landing, except for IL-1ra, which was still higher (five- to sixfold) than in controls. This phenomenon was accompanied by an increased expression of Toll-like receptor 4 and decreased expression of CD14 on the crew members' monocytes at all time points. There were also increased levels of the lipopolysaccharide binding protein in the plasma of the crew members 3 to 4 h and 15 days after landing. This study shows that spaceflight-associated factors (in-flight and preflight) modulate the response of monocytes to gram-negative endotoxins.