B GINGIVALIS POLYSACCHARIDES--STRUCTURE AND FUNCTION

B 牙龈多糖——结构和功能

• 批准号: 3462328
• 负责人: ROBERT E SCHIFFERLE
• 金额: $ 8.64万
• 依托单位: STATE UNIVERSITY OF NEW YORK AT BUFFALO
• 依托单位国家: 美国
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-04-01 至 1996-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3462328
• 关键词: Bacteroides gingivalis; antiantibody; antibody formation; bacterial capsules; bacterial polysaccharides; blood donor; complement; genetic strain; gingivitis; human subject; immunogenetics; laboratory mouse; neutrophil; periodontitis; phagocytosis; serotyping

Bacterial encapsulation is frequently correlated with an enhancement of virulence. Encapsulated strains of Escherichia coli, Neisseria meningitidis, and Haemophilus influenzae demonstrate enhanced invasive properties and cause serious disease, while their unencapsulated counterparts are generally much less virulent. In the USA, capsular polysaccharide vaccines are commercially available for the prevention of disease by Ii. influenza type b, Streptococcus pneumoniae, and other encapsulated bacteria. Bacteroides gingivalis is an anaerobic gram-negative bacteria associated with periodontal disease. Previous studies have demonstrated the presence of a capsule on B. gingivalis and have attributed antiphagocytic properties to this capsule. This proposal will study the ability of this polysaccharide to contribute to this microorganism's virulence and the ability of this polysaccharide to function as an immunogen and induce the formation of protective antibodies, thus resulting in protection from infection with this bacteria. This proposal seeks to characterize the polysaccharides from different strains of B_. gingivalis, to use these polysaccharides as immunogens, and to study their biological effects. Polysaccharides will be isolated from different strains and chemically and immunochemically characterized. The immunogenicity of these polysaccharide will then be assessed by using: modified polysaccharide derivatives, polysaccharide-protein conjugate vaccines, different immunological adjuvants, and agents that can either stimulate or suppress different T cell populations which are involved in the immune response to polysaccharide antigens. The ability of these polysaccharide immunogens to modify the development of infection in an experimental mouse virulence model will then be investigated. The interaction of the polysaccharide with the serum complement system and its effect on phagocytosis by neutrophils will be determined. Finally, unencapsulated strains of B. gingivalis will be derived either by natural selection or through transposon mutagenesis and the virulence properties of these unencapsulated strains will be compared with the encapsulated bacteria. The results of these studies should greatly enhance our knowledge of the immunogenicity of bacterial polysaccharide antigens and to the contribution of the capsule to the virulence observed for B. gingivalis.

细菌包囊化通常与 增强毒力。 大肠杆菌的微囊化菌株 大肠杆菌、脑膜炎奈瑟菌和流感嗜血杆菌 表现出增强的侵入性并导致严重疾病， 而它们未封装的对应物通常要少得多， 致命的 在美国，荚膜多糖疫苗是 可商购获得的用于预防Ii. 流感B型、肺炎链球菌和其它包囊 细菌 牙龈拟杆菌是一种厌氧的革兰氏阴性菌， 牙周病的症状有哪些？ 先前的研究已经证明了胶囊的存在 在B。牙龈炎，并将抗吞噬特性归因于 这个胶囊。 本建议将研究这种能力 多糖有助于这种微生物的毒力， 这种多糖作为免疫原发挥作用的能力， 诱导保护性抗体的形成，从而导致 防止感染这种细菌。 该提案旨在表征来自 不同菌株的B_。牙龈炎，使用这些多糖 作为免疫原，并研究其生物学效应。 多糖将从不同的菌株中分离， 化学和免疫化学表征。 免疫原性 然后将通过使用以下参数来评估这些多糖的含量： 多糖衍生物、多糖-蛋白质结合物 疫苗，不同的免疫佐剂，以及可以 刺激或抑制不同的T细胞群， 参与对多糖抗原的免疫反应。 的 这些多糖免疫原的能力，以修改 实验小鼠毒力模型中感染的发展 将被调查。 多糖的相互作用 与血清补体系统及其对吞噬作用的影响 将测定中性粒细胞。 最后，未被包囊的菌株 的B。牙龈将通过自然选择或 通过转座子诱变和毒力特性， 将这些未包封的菌株与包封的菌株进行比较， 细菌 这些研究的结果将大大提高我们的 对细菌多糖免疫原性的认识 抗原和荚膜对毒力的贡献 观察到B。牙龈炎