Identification of functional fimbria domain of periodontopathogen for the clinical application

牙龈卟啉单胞菌（Porpnyromonas gingivalis）是一种牙周病病原菌，可通过内吞途径进入宿主牙周细胞，参与牙周病的发生、发展。本研究旨在从菌毛蛋白的毒力和细菌细胞内定位两个方面阐明牙周病慢性化的机制。牙龈卟啉单胞菌被牙龈上皮细胞侵入并退出细胞外环境。本研究表明，牙龈卟啉单胞菌从牙龈上皮细胞的退出是由Rabll，RalA和外囊复合物介导的。提示牙龈卟啉单胞菌可抑制先天免疫反应，从而导致牙周病的慢性化。

Porpnyromonas gingivalis, a periodontal pathogen, can enter host periodontal cells via endocytic pathway, which is involved in the disease progression. The present study was performed to elucidate the mechanism of the chronic situation of periodontal diseases in terms of the virulence of fimbrillin and of the bacterial intracellular localization. P.gingivalis was invaded by gingival epithelial cells and exited to extracelluolar milieu. This study suggests that the exit of P.gingivalis from gingival epithelial cells is mediated by Rabll, RalA, and exocyst complex. It also suggests that P.gingivalis can avoide the innate immune response, which can lead to the chronic situation of periodontal diseases.