【摘要】 目的探索PM2.5对基因敲除小鼠脾细胞NF-kB影响的作用机制。方法野生型（WT）、Toll样受体（TLR）2、TLR4及髓鞘分化因子（MyD）88基因敲除(MyD88^-/-)小鼠经气管内PM2.5染毒,每2周1次,共染毒4次,最后一次染毒24 h后处死。检测脾细胞活性及细胞培养液中细胞因子白细胞介素2（IL-2）及肿瘤坏死因子-2（TNF-α）,的表达水平。检测脾细胞NF-κB的活化及表达水平。结果 PM2.5染毒后野生型（WT）小鼠脾细胞ATP水平明显升高（P<0.05）,在Toll样受体（TLR）2^-/-小鼠中也发现PM2.5诱导脾细胞的ATP水平升高（P<0.05）,而在TLR4^-/-小鼠中未发现PM2.5对脾细胞的影响（P>0.05）。此外,在WT和TLR2^-/-小鼠中,PM2.5促进ConA诱导的IL-2及LPS诱导的TNF-α水平的增加（P<0.05）,而在TLR4^-/-和MyD88^-/-小鼠中则没有明显变化（P>0.05）。免疫印迹也显示在WT和TLR2^-/-小鼠中PM2.5诱导NF-κB的活化,而在TLR4^-/-和MyD88^-/-小鼠中NF-κB没有被激活。结论 PM2.5通过TLR4^-/-和MyD88^-/-途径激活脾细胞中NF-κB信号通路引起脾细胞炎性反应。更多还原

【Abstract】 Objective To investigate the action mechanism of PM2.5 induced NF-κB activation in splenocytes of gene knockout mice through the TLR4 and MyD88 pathway.Methods The wild type（WT）, toll-like receptor（TLR）2^-/-,TLR4^-/- and myeloid differentiation factor（MyD）88^-/- mice were intratracheally administrated PM2.5 for 4 times（once every two week for 8 weeks） and were sacrificed at 24 h after the final administration.The splenocyte activity and the expression levels of IL-2 and TNF-α in cell culture fluid were measured by cell viability assay and ELISA,respectively.Moreover the activation and expression levels of NF-κB in splenocytes were detected by Western Blot. Results The ATP levels in splenocytes of WT mice after the mice were administrated PM2.5 were significantly increased（P<0.05）,moreover,the ATP levels in TLR2^-/- mice were significantly increased（P<0.05）,however, the effects of PM2.5 on splenocytes were not found in TLR4^-/- mice（P>0.05）.Moreover the increase of ConA-induced IL-2 and the increase of LPS-induced TNF-α were found in WT mice and TLR2^-/- mice（P<0.05）, but not in TLR4^-/- mice or MyD88^-/- mice（P>0.05）. Western Blot results showed that the NF-κB activation occurred in WT mice and TLR2^-/- mice,but not in TLR4^-/- mice or MyD88^-/- mice.Conclusion PM2.5 can activate NF-κB signal pathway in splenocytes to induce splenocyte inflammation reaction through TLR4 and MyD88 pathway.更多还原