MOLECULAR ANALYSIS OF T. DENTICOLA-HOST INTERACTIONS

描述：螺旋体在龈下菌斑中的优势与 严重的牙周病变表明，在牙周的重要作用， 发病机制本研究的目的是描述 龈下组织中齿垢密螺旋体的分子水平研究。通过 重点分析直接影响宿主的表面表达蛋白 细胞，深入了解牙周细胞病理学的机制。 T.齿垢与细胞和ECM结合 组分，并具有成孔细胞毒活性。msp基因 在许多口腔螺旋体中保守，但显示出相当大的菌株间 异质性，表明它是一种重要的免疫原。整体 假设Msp是牙周炎中重要毒力决定因子， 疾病，是一个外膜蛋白复合物的关键组成部分，介导 螺旋体与龈下组织的相互作用。 拟议研究的具体目标，以及将被纳入的个人假设 试验的主要内容是：1）对T. Msp相关蛋白 表情对于天然药物，需要Msp以外的外膜组件 天然外膜复合物的msp表达和组装。等基因 突变体和重组表达系统将用于表征这些 流程. 2)鉴定Msp的免疫显性结构域和功能结构域。 Msp的抗原异质性是影响口腔粘膜上皮细胞免疫应答的一个因素 螺旋体将对存档的血清样本进行反应性筛选， 特定的MSPs。将在患者斑块中鉴定编码新型Msps的基因 样品3)为了表征Msp在致细胞病变细胞应答中的作用， t.齿垢亲本和msp突变株结合宿主细胞的能力 ECM和血清成分，并激活促炎细胞反应 将被检测。在上皮细胞表面鉴定出一种推定的Msp受体 将被定性。 这些研究涉及遗传和生化分析， 旨在为理解微生物宿主 牙周病的病因学的相互作用，以及牙周病的基本知识， 致病螺旋体的分子生物学

DESCRIPTION: The predominance of spirochetes in subgingival plaque associated with severe periodontal lesions suggests an important role in periodontal pathogenesis. The goal of this research is to characterize interactions of Treponema denticola with subgingival tissues at the molecular level. By focusing on analysis of surface-expressed proteins that directly affect host cells, insights will be gained into mechanisms of periodontal cytopathology. The major outer membrane protein (Msp) of T. denticola binds to cells and ECM components, and has pore-forming cytotoxic activity. Msp is genetically conserved in many oral spirochetes, yet shows considerable inter-strain heterogeneity, suggesting that it is an important immunogen. The overall hypothesis is that Msp is a significant virulence determinant in periodontal disease, and is a key component of an outer membrane protein complex mediating interactions of the spirochete with subgingival tissue. Specific Aims of the proposed research, and the individual hypotheses to be tested are: 1) to characterize T. denticola proteins associated with Msp expression. Outer membrane components other than Msp are required for native Msp expression and assembly of the native outer membrane complex. Isogenic mutants and recombinant expression systems will be used to characterize these processes. 2) to identify immunodominant and functional domains of Msp. Antigenic heterogeneity of Msp is a factor in host antibody recognition of oral spirochetes. Archived serum samples will be screened for reactivity with specific Msps. Genes encoding novel Msps will be identified in patient plaque samples. 3) to characterize the role of Msp in cytopathic cellular responses to T. denticola. The ability of parent and msp mutant strains to bind host cells, ECM and serum components, and to activate pro-inflammatory cellular responses will be assayed. A putative Msp receptor identified on epithelial cell surfaces will be characterized. These studies, which involve both genetic and biochemical analyses, are intended to contribute significantly to the understanding of microbe-host interactions in the etiology of periodontal diseases, and to basic knowledge of the molecular biology of pathogenic spirochetes.