脓肿分枝杆菌诱导巨噬细胞产生TNF-α和IL-8的相关分子机制

A study on the molecular mechanisms of TNF-α and IL-8 production in macrophages induced by Mycobacterium abscessus

目的探索脓肿分枝杆菌脓肿亚种和马赛亚种诱导THP-1巨噬细胞分泌肿瘤坏死因子α(TNF-α)和白介素8(IL-8)的相关分子机制。方法将脓肿分枝杆菌脓肿亚种和马赛亚种感染THP-1巨噬细胞,ELISA检测THP-1巨噬细胞被感染6、18、24、48、72 h内分泌TNF-α和IL-8情况,及分别抑制TLR2受体、MAPKs中3种信号分子(JNK信号蛋白、ERK信号蛋白和P38 MAPK)和NF-κB后,THP-1巨噬细胞被感染48 h后分泌TNF-α和IL-8情况。结果脓肿亚种和马赛亚种致TNF-α和IL-8分泌呈时间依赖性,在作用THP-1巨噬细胞48 h后致TNF-α和IL-8分泌达高峰,脓肿亚种所致TNF-α分泌量高于马赛亚种,差异有统计学意义(P <0.01);分别抑制相应信号分子后,脓肿亚种和马赛亚种所致的TNF-α和IL-8分泌水平均出现明显抑制,与感染阳性对照差异均有统计学意义(均P <0.05)。结论脓肿分枝杆菌脓肿亚种和马赛亚种均可经TLR2信号途径、MAPKs信号途径和NF-κB信号途径诱导TNF-α和IL-8的分泌,脓肿亚种对TNF-α的诱导作用较强于马赛亚种。

Objective To investigate the molecular mechanisms and deferention of TNF-α and IL-8 production in THP-1 macrophages induced by Mycobacterium abscessus subsp. abscessus(M. abscessus subsp.abscessus) and Mycobacterium subsp. massiliense(Mmass). Methods THP-1 macrophages were cultured in the presence of M. abscessus subsp. abscessus and Mmass to stimulate ytokine expression. TNF-α and IL-8 in THP-1 macrophages infected with M.abscessus subsp.abscesss and Mmass for 6, 18,24,48,and 72 h were analyzed by ELISA, and paralleled for detection of changes in TNF-α and IL-8 levels with anti-TLR2 mAb, JNK signaling inhibitor, ERK signaling inhibitor, P38 signaling inhibitor and NF-κB inhibitor respectively after infected for 48 h.Results TNF-α and IL-8 were the time-dependent manner production in THP-1 macrophages infected with M.abscessus subsp. abscessus and Mmass, and showed peak levels at 48 hours. For M.abscessus subsp. abscessus, the production of TNF-α induced was higher than that of Mmass-induced(P < 0.01); Compared with the production induced by M.abscessus subsp. abscessus and Mmass, the increase in TNF-α and IL-8 levels at 48 hours were downregulated significantly in the presence of five deferent signaling inhibitors(P < 0.05). Conclusions Both M.abscessus subsp. abscesss and Mmass can cause an increase in TNF-α and IL-8 production through TLR2 pathway, MAPKs pathway and NF-κB pathway, and M. abscessus subsp. abscessus induces higher production of TNF-αthan Mmass.