免疫抑制小鼠内毒素血症时免疫细胞功能紊乱的实验观察

RESEARCH ON IMMUNOLOGIC DISORDER IN THE IMMUNITY IMMUNODEPRESSION AND ENDOTOXEMIA MICE

目的:本研究在建立免疫抑制小鼠内毒素血症模型的基础上,观察机体免疫紊乱状态。方法:选取Blbc/c小鼠,连续3d腹腔内注射甲基强的松龙30mg/kg,建立免疫抑制小鼠模型,3d后静脉注射10mg/kg剂量内毒素,于2,6h时点取血浆,分别采用化学比色法检测一氧化氮(NO)、TNF-α、INF-γ、IL-2、IL-4、IL-10、IL-18等细胞因子水平,以反映TH1、TH2以及巨噬细胞等免疫细胞的功能与状态。在此基础上,50只小鼠分为免疫抑制内毒素血症模型组(模型组)以及甲基强的松龙对照组(激素组)与空白对照组。此外,还观察其肺部病理学改变。结果:在激素组,与正常组小鼠比较,各时点的血浆NO变化不大,TNF-α有降低的趋势,而IL-18则明显降低;INF-γ、IL-2的水平降低明显,IL-4、IL-10的水平则处于正常水平,其中IL-10还稍有升高趋势。在内毒素组的各时点,与正常组比较,模型小鼠肺组织有出血、水肿和炎细胞浸润等急性肺损伤等病理改变,而且INF-γ、IL-2水平明显降低,IL-4水平有升高趋势,IL-10水平升高明显;此外,在注射LPS后2h时点,NO与TNF-α水平明显升高,在注射LPS后6h时点,而NO、TNF-α以及IL-18水平均显著升高。结论:免疫抑制内毒素血症模型小鼠的TH1细胞功能低下,而TH2细胞与巨噬细胞处于活化状态,机体炎症反应则类似MARS的特点。

Objective：To observe the immunologic disorder in the mouse model of immunity immunodepres- sion and endotoxemia. Methods： Establishment of mouse model of immunity immunodepression and endo- toxemia： Blbe/c mouse was induced by intraperitoneal injection of methylprednisolone （30 mg/kg/d） for 3 days and then LPS （10 mg/kg）. Fifty mice were divided into immunity immunodepression and endotox- emia, methylprednisolone, and normal control groups. Nitric oxidation （NO） was detected by chromatom- etry and cytokines of TNF-α, INF-γ, IL-2, IL-4, IL-10 and IL-18 were detected by ELISA. In addition, pulmonary pathological changes were detected by HE staining. Results： In methylprednisolone group, there was no change of NO, and decreased tendency of TNF-α and significantly decreased expression level of IL-18. The levels of INF-γand IL-2 decreased significantly and the levels of IL-4, IL-10 maintained nor- mal level. In the group of immunity immunodepression and endotoxemia, the pathological changes of acute lung injury were as follows： pulmonary interstitial hyperemia and hemorrhage, inflammation cell infiltra- tion, and pulmonary septal thickening. At the all time point, the levels of INF-γ and IL-2 decreased signif- icantly, the level of IL-10 increased significantly, and the IL-4 was in high level. At 2 h time point, NO and TNF-α increased significantly. At 6 h time point, the levels of NO, TNF-α and IL-18 increased significant-ly as compared with the control group. Conclusion： In this mouse model of immunity immunodepression and endotoxemia, the function of TH1 is decreased, the function TH2 and macrophage are increased.