目的:探讨脑缺血再灌注小鼠诱导免疫抑制与肺部感染易感性的关系。方法:取32只体重20～25 g的C57BL/6J雄性小鼠，按随机数字法分为对照组(CON组)、肺部感染模拟组(SP组)、脑缺血再灌注组(MCAO组)、脑缺血再灌注后肺部感染模拟组(SAP组)，每组各8只。通过线栓法建立MCAO模型及向气管内定量注入致病菌模拟肺部感染的发生。24 h后收集各组外周血及肺泡灌洗液(BAL)并检测肿瘤坏死因子-α (TNF-α)、干扰素-γ (IFN-γ)、白细胞介素-10 (IL-10)表达量，计算BAL、血标本、肺匀浆中的菌落计数(CFU)；72 h后观察肺和脾组织的病理改变并统计肺组织病理评分、脾指数，计算MCAO组及SAP组脑梗死体积。组间比较采用n t检验。n 结果:SAP组外周血TNF-α、IFN-γ低于CON组[(87.20±4.37) ng/L比(112.96±9.91) ng/L、(86.71±11.25) ng/L比(126.42±14.61) ng/L，n t＝5.320、4.815，n P<0.05]，差异有统计学意义，而IL-10水平高于CON组[(192.36±20.23) ng/L比(148.85±22.35) ng/L，n t＝-3.227，n P<0.05]，差异有统计学意义；BAL中SAP组除TNF-α高于SP组[(47.13±3.84) ng/L比(64.31±11.25) ng/L，n t＝-3.236，n P<0.05]外，其余炎性因子水平与CON及SP组差异无统计学意义。SAP组外周血、BAL及肺匀浆中的荷菌量明显高于SP组[(6.77±16.79)×10n 4 CFU/ml比0 CFU/ml、(14.07±7.59)×10n 5 CFU/ml比(7.69±14.74)×10n 4 CFU/ml、(5.03±2.85)×10n 6 CFU/ml比(9.76±9.24)×10n 4 CFU/ml]。光镜下显示SAP组肺部炎症严重程度高于CON组，但低于SP组，与肺组织病理评分相一致(9.00±2.27比0.53±0.30、15.20±2.52比0.53±0.30，n t＝-8.264、3.203，n P0.05]。n 结论:卒中诱导的免疫抑制增加发生肺部感染的易感性。“,”Objective:To investigate the correlation between cerebral ischemia-reperfusion-induced immunodeficiency and susceptibility of pneumonia in mice.Methods:Totally, 32 C57BL/6J male mice weighing 20-25 gwere divided by random digit method into control group (CON), Streptococcus pneumonia (SP) model group (SP group), middle cerebral artery occlusion reperfusion (MCAO) group (MCAO group), stroke-associated pneumonia (SAP) model group (SAP group), and 8 per group. At 24h after the operation, the peripheral blood and bronchoalveolar lavage (BAL) in each group were collected to detect the tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), interleukin-10 (IL-10) by enzyme linked immunosorbent assay (ELISA); BAL, peripheral blood and lung homogenate were used for bacterial culture by blood plate; The volume of cerebral infarction in MCAO and SAP groups was calculated by 2, 3, 5, -triphenyltetrazolium chloride (TTC) staining after 72 h. The above indicators were statistically analyzed by SPSS 22.0 software.Results:The levels of TNF-α and IFN-γ in SAP group were lower than those in CON group [(87.20±4.37) ng/L vs. (112.96±9.91) ng/L, (86.71±11.25) ng/L vs. (126.42±14.61) ng/L,n t=5.320, 4.815, n P<0.05], and IL-10 level was higher in SAP group than that in CON group [(192.36±20.23) ng/L vs. (148.85±22.35) ng/L,n t=-3.227, n P0.05), except for the TNF-α between SAP and SP groups [(47.13±3.84) ng/L vs. (64.31±11.25) ng/L,n t=-3.236, n P0.05].n Conclusion:Stroke-induced immunodeficiency is a risk factor for pneumonia after stroke.