INTERACTION OF ORAL SPIROCHETES WITH GINGIVAL EPITHELIUM

口腔螺旋体与牙龈上皮的相互作用

• 批准号: 6776056
• 负责人: Sheila A. Lukehart
• 金额: $ 24.09万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-03-01 至 2007-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6776056
• 关键词: Treponema; bacteria infection mechanism; bacterial proteins; bactericidal immunity; cell migration; cytokine; defensins; endopeptidases; epithelium; gene expression; gingiva; human tissue; immune response; immunogenetics; oral bacteria; oral mucosa; protein binding; tissue /cell culture

DESCRIPTION (provided by applicant): Oral spirochetes, including Treponema denticola, comprise about 40 percent of the bacteria in periodontal pockets and are linked to the progression and severity of periodontal disease. Despite their obvious relevance to periodontal disease, they are vastly understudied. Oral spirochetes are usually found in close association with the gingival epithelium, but our understanding of how T. denticola and other oral spirochetes establish themselves at this interface is limited. T. denticola and other oral spirochetes likely have evolved strategies to avoid host immune defenses, specifically the defenses initiated by the epithelial cell. The proposed studies will focus on the interactions of spirochetes with gingival epithelial cells and the modulation of molecules produced by these cells in response to bacterial challenge. Our studies to date demonstrate that T. denticola is resistant to a-defensins, and the susceptibility of other oral treponemes to beta-defensins will be examined (Aim 1). To define the mechanisms used by T. denticola to resist beta-defensins killing, we will explore strategies used by other bacteria to resist antimicrobial peptides, including bacterial proteases, binding of defensin to cell surfaces, and efflux pumps (Aim 2). The ability of T. denticola and other oral treponemes to induce production of beta-defensins will be examined in Aim 3. Our preliminary data suggest that T. denticola inhibits the induction of inflammatory cytokines by other bacterial products, similar to the "chemokine paralysis" that has been described for Porphyromonas gingivalis LPS. We will examine the modulation of cytokines and adhesion molecules from epithelial cells stimulated by T. denticola (Aim 4), with the goal of identifying the signaling pathways that are affected by the spirochetes. Lastly, we will determine the components of T. denticola (Aim 5) that induce production of a-defensins and antagonize the induction of inflammatory cytokines. This study will further our understanding of the pathogenesis of periodontal disease by providing a more complete understanding of how T. denticola and other oral spirochetes evade the innate immune response.

描述（由申请人提供）：口腔螺旋体，包括齿垢密螺旋体，构成牙周袋中约40%的细菌，并与牙周疾病的进展和严重程度有关。尽管它们与牙周病有明显的相关性，但它们的研究还远远不够。口腔螺旋体通常与牙龈上皮紧密相连，但我们对T。齿垢和其它口腔螺旋体在该界面上的建立是有限的。T.齿垢和其他口腔螺旋体可能已经进化出了避免宿主免疫防御的策略，特别是由上皮细胞发起的防御。拟议的研究将集中在螺旋体与牙龈上皮细胞的相互作用，以及这些细胞在应对细菌挑战时产生的分子的调节。我们的研究表明T.齿垢对α-防御素具有抗性，并且将检测其它口腔密螺旋体对β-防御素的易感性（目的1）。定义T.为了研究如何利用细菌来抵抗β-防御素杀伤，我们将探索其他细菌抵抗抗菌肽的策略，包括细菌蛋白酶，防御素与细胞表面的结合，以及外排泵（Aim 2）。T.目的3中将研究口腔密螺旋体和其它口腔密螺旋体诱导β-防御素产生的作用。我们的初步数据表明T.齿垢抑制其它细菌产物对炎性细胞因子的诱导，类似于牙龈卟啉单胞菌LPS所描述的“趋化因子麻痹”。我们将研究T细胞刺激的上皮细胞的细胞因子和粘附分子的调节。目的4），目的是确定受螺旋体影响的信号通路。最后，我们将确定T的分量。Denticola（Aim 5），其诱导α-防御素的产生并拮抗炎性细胞因子的诱导。本研究将通过提供一个更完整的了解如何T。齿垢和其他口腔螺旋体逃避先天免疫反应。