胞内分枝杆菌及偶发分枝杆菌对小鼠巨噬细胞凋亡的影响

Effects of Mycobacterium intracellulare and Mycobacterium fortuitum on apoptosis of macrophages in mice

为了研究非结核分枝杆菌对巨噬细胞凋亡的影响,采用胞内分枝杆菌和偶发分枝杆菌分别感染小鼠巨噬细胞系RAW264.7,流式细胞术检测细胞凋亡率,ELISA法检测TNF-α及IL-10的表达,检测这2株菌在小鼠巨噬细胞中的增殖。结果显示:胞内分枝杆菌引起的细胞凋亡水平低于偶发分枝杆菌组(P<0.05),这2株菌所引起的TNF-α的表达量在4 h、12 h较高,与空白对照组相比差异显著(P<0.05),在24 h、48 h下降明显,而IL-10的表达整个感染过程都比较高。并且还观察到胞内分枝杆菌的吞噬率较高(P<0.05);增殖能力较强(P<0.01)。表明菌体毒力与凋亡率、细胞因子的表达、增殖率有着直接关系。

In order to study the effect of non-tuberculosis mycobacterium on macrophage apoptosis,mycobacterium intracellulare and mycobacterium fortuitum to infect mouse macrophage line RAW264.7.Then flow cytometry was used to detect the apoptotic rate,and ELISA was used to detect the expression of TNF-alpha and IL-10.The proliferation of these two strains in mouse macrophages was also analyzed.Our results showed that the apoptotic rate induced by mycobacterium intracellulare was lower than that induced by mycobacterium fortuitum(P<0.05).The expression of TNF-alpha induced by these two strains was higher at 4 h and 12 h than that of blank control group(P<0.05).The expression of TNF-α decreased significantly at 24 h and 48 h post infection,while the expression of IL-10 was higher through out the infection process.We also observed that the phagocytosis rate of Mycobacterium intracellulare was higher(P<0.05)and the proliferation ability was stronger(P<0.01).The results showed that the virulence of bacteria was directly related to the apoptotic rate,the expression of cytokines and the proliferation rate.