Recognition mechanisms of extracellular bacteria by intracellular sensors.

变形链球菌、戈登链球菌和血链球菌是口腔中的常住菌胞外病原体，可诱导A/J小鼠来源的树突状细胞系XS-106细胞产生IL-1b，并呈剂量依赖关系。血链球菌诱导IL-1b产生的活性依赖于caspase-1和NLRP3。因此，本研究提示口腔链球菌可激活NLRP3炎症体，在小鼠树突状细胞中产生IL-1b。

S. mutans, S. gordonii and S. sanguinis, as extracellular pathogens, which are normal inhabitants of the human oral cavity, induced IL-1b production by the dendritic cell line XS-106 cells derived from A/J mice in dose-dependent manners. The activity of S. sanguinis to induce IL-1b production was dependent on caspases-1 and NLRP3. Thus, this study suggests that oral streptococci activate NLRP3 inflammasome to produce IL-1b in murine dendritic cells.