Department of Microbiology and Immunology, School of Medicine, Jinan University, Guangzhou 510632, China.
Curr Microbiol. 2013 Oct;67(4):414-22. doi: 10.1007/s00284-013-0380-z. Epub 2013 May 16.
Although intestinal flora are crucial in maintaining immune homeostasis of the intestine, the role of intestinal flora in immune responses at other mucosal surfaces remains less clear. Here, we show that intestinal flora composition critically regulates the toll-like receptor 7 (TLR7) signaling pathway following respiratory influenza virus infection. TLR7 ligands rescued the immune impairment in antibiotic-treated mice. Intact microbiota provided signals leading to the expression of mRNA for TLR7, MyD88, IRAK4, TRAF6, and NF-κB at steady state. Significant changes in the composition of culturable commensal bacteria reduced the expression levels of components of the TLR7 signaling pathway. Our results reveal the importance of intestinal flora in regulating immunity in the respiratory mucosa through the upregulation of the TLR7 signaling pathway for the proper activation of inflammasomes.
尽管肠道菌群对于维持肠道的免疫稳态至关重要，但肠道菌群在其他黏膜表面的免疫反应中的作用仍不明确。在这里，我们发现肠道菌群组成在呼吸道流感病毒感染后，会严格调控 toll 样受体 7（TLR7）信号通路。TLR7 配体挽救了抗生素处理小鼠的免疫损伤。完整的微生物群提供了信号，导致 TLR7、MyD88、IRAK4、TRAF6 和 NF-κB 的 mRNA 在稳定状态下表达。可培养共生菌组成的显著变化降低了 TLR7 信号通路组成成分的表达水平。我们的结果揭示了肠道菌群通过上调 TLR7 信号通路对炎性小体的适当激活，在调节呼吸道黏膜免疫中的重要性。
