Response of oral mucous epitherial cells for infection of pathogenic bacteria of periodontitis.

本研究的目的是探讨口腔粘膜上皮细胞对牙周炎的主要病原菌-牙龈卟啉单胞菌感染的反应。脂多糖（LPS）是牙龈卟啉单胞菌的主要致病因子之一，本文研究了牙龈卟啉单胞菌LPS对小鼠龈沟上皮细胞系GEL细胞的影响。主要研究结果如下：1. LPS的膜受体。Givalis P. givalis LPS可促进GE 1细胞Toll样受体（TLR）4 mRNA的积累，但对CDL 4和TLR 2基因的表达无明显影响。通过流式细胞仪分析和使用特异性抗体的免疫组化，这些受体可在GEl的细胞质膜上检测到。GE 1细胞中CD 14的表达水平与巨噬细胞样细胞J774相当。1，而TLR 2和TLR 4水平明显降低.唾液腺上皮对脂多糖的反应。牙龈卟啉单胞菌LPS可促进GE 1细胞增殖。通过与Givalis P. gingalis LPS孵育改变炎性细胞因子（如TNFcz、IL-1β和IL-6）和趋化因子（如IL-8和炎性蛋白2）的基因表达。2D-FAGE和ECL Western blotting结果显示，Gingivalis LPS可诱导牙周膜上皮细胞对Gingivalis LPS产生反应，且Gingivalis LPS的受体可能与巨噬细胞不同。

The aim of this study is to investigate the response of oral mucous epithelial cells to infection of a major bacterial pathogens of periodontalis, Porphyromonas gin givalis. Since lipopolysaccharide (LPS) is one of major vilulence factors of P. gin givalis, effects of P. gingivalis LPS on mouse sulcular epithelium cell line, GEL cells, were studies. The obtained results are as follows:1. Membrane receptors for LPS. P. gin givalis LPS enhanced accumulation of Toll-like receptor (TLR) 4 mRNA in GEl cells, but did not significantly affect on expression of CDL4 and TLR2 genes. These receptors were detectable on cytoplasmic membrane of GEl by analysis with a flowcytometer and immunohistochemistry by using specific antibodies. The expression level of CD14 in GEl cells was comparable to that in macrophage-like cell, J774. 1, whereas the levels of TLR2 and TLR4 were apparently lower.2. Responses of suiclar epithelium against LPS. Cell proliferation of GEl increased by P. gin givalis LPS. Gene expression of inflammatory cytokines, such as TNFcz, IL-1β and IL-6, and chemokines, such as IL-8 and inflammatory protein 2, altered by incubation with P. gin givalis LPS. Concomitant with these responses, phosphorylation of Thr and Tyr residues of GE1 proteins was demonstrated by 2D-FAGE and ECL Western blotting.These results suggested that sulclar epithelium cells could response to periodontal virulence factors of P.gin givalis LPS and that receptors for LPS may be different from those reported on macrophages.