Neisserial Porins and Antigen Presenting Cells

奈瑟氏球菌孔蛋白和抗原呈递细胞

• 批准号: 6737448
• 负责人: LEE Mark WETZLER
• 金额: $ 41.71万
• 依托单位: BOSTON MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-04-01 至 2006-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6737448
• 关键词: B lymphocyte; Neisseria gonorrhoeae; Neisseria meningitidis; Neisseriaceae; antigen antibody reaction; antigen presenting cell; bacterial proteins; bacterial toxins; biological signal transduction; confocal scanning microscopy; dendritic cells; enzyme linked immunosorbent assay; genetically modified animals; green fluorescent proteins; immunoprecipitation; laboratory mouse; leukocyte activation /transformation; lipopolysaccharides; mitogen activated protein kinase; nuclear factor kappa beta; polymerase chain reaction; pore forming protein; protein tyrosine kinase; toll like receptor; toxin metabolism; western blottings

Neisserial porins (gonococcal Protein I [PIA or PIB] or meningococcal class 1 [PorA], 2 or 3 [PorB] proteins) are the major protein constituent of the Neisserial outer membrane. They have significant homology in structure and function amongst themselves and other Gram-negative porins. We have previously demonstrated that the Neisserial porins activate B lymphocytes, increasing the surface expression of the costimulatory ligand B7- 2, which improves the B cell's ability to "costimulate" T lymphocytes. The induction of B7-2 expression is directly related to the porins' adjuvant ability. As Neisserial porins are molecules that maintain a common "pattern" present on Gram- negative organisms, it is probable that the activation of antigen presenting cells (APC), including B cells and dendritic cells, is through pattern recognition receptors. A family of these receptors has recently been described by which a number of conserved bacterial products including LPS, bacterial lipopeptides, peptidoglycan, etc., can mediate cell activation and induction of costimulatory molecules. These have been termed Toll-like receptors (TLR) because of their significant homology to receptors present in Drosophila that are important for innate immunity. The TLR family of receptors have also been shown to be the main mediators of innate immune responses that have previously been described for these microbial products. We have preliminary data demonstrating that B cell activation by Neisserial porins is mediated through signaling by one of these TLRs, namely TLR2. The overriding hypothesis of this proposal is that the immune stimulatory effect of Neisserial porins and, therefore, their adjuvant activity, is due to an interaction of the porins with TLR2 on antigen presenting cells (especially B cells and dendritic cells) and this event initiates a set of common signal transduction events that induces cell activation and increases B7-2 and class II MHC surface expression. The following aims of the proposal will attempt to prove this hypothesis: 1) investigate the interaction of Neisserial porin with TLR2 and demonstrate the importance of TLR2 mediated signaling in their adjuvant activity, 2) explore the significance of signal transduction events induced in B cells and dendritic cells (including NF-kappaB activation protein tyrosine kinase activation and MAPKK activation) by Neisserial porins in relationship to their adjuvant activity and whether these events are due to immune cell stimulation through TLR2, and 3) determine whether dendritic cell activation by the Neisserial porins is mediated through TLR2 and if their ability to activate dendritic cells is related to the their immunopotentiating activity.

奈瑟氏菌（淋球菌蛋白I [PIA或PIB]或脑膜炎球菌1 [pora]，2或3 [PORB]蛋白）是奈瑟氏外膜的主要蛋白质成分。 它们在彼此之间以及其他革兰氏阴性波的结构和功能方面具有重要的同源性。 我们以前已经证明，奈瑟氏菌孔蛋白激活B淋巴细胞，增加了凸出配体B7-2的表面表达，从而提高了B细胞“ costaute” T淋巴细胞的能力。 B7-2表达的诱导与孔蛋白的辅助能力直接相关。 由于静脉孔蛋白是在革兰氏阴性生物上保持常见“模式”的分子，因此抗原呈递细胞的激活（包括B细胞和树突状细胞）很可能通过模式识别受体。最近已经描述了这些受体的家族，其中许多保守的细菌产物，包括LPS，细菌脂肽，肽聚糖等，可以介导细胞激活和诱导共刺激分子。 这些被称为Toll样受体（TLR），因为它们与果蝇中存在的受体具有重要同源性，对先天免疫很重要。 TLR的受体家族也已被证明是先前用于这些微生物产物的先天免疫反应的主要介体。 我们的初步数据表明，奈瑟氏孔蛋白的B细胞激活是通过这些TLR之一（即TLR2）信号传导介导的。 The overriding hypothesis of this proposal is that the immune stimulatory effect of Neisserial porins and, therefore, their adjuvant activity, is due to an interaction of the porins with TLR2 on antigen presenting cells (especially B cells and dendritic cells) and this event initiates a set of common signal transduction events that induces cell activation and increases B7-2 and class II MHC surface expression. The following aims of the proposal will attempt to prove this hypothesis: 1) investigate the interaction of Neisserial porin with TLR2 and demonstrate the importance of TLR2 mediated signaling in their adjuvant activity, 2) explore the significance of signal transduction events induced in B cells and dendritic cells (including NF-kappaB activation protein tyrosine kinase activation and MAPKK activation) by Neisserial porins in relationship对于它们的辅助活性以及这些事件是否是由于通过TLR2刺激的免疫细胞刺激，以及3）确定奈瑟氏骨porins的树突状细胞激活是否通过TLR2介导，以及它们激活树突状细胞的能力是否与其免疫肠肠性活性有关。