Immunology of Infection with Neisseria gonorrhoeae

淋病奈瑟菌感染的免疫学

• 批准号: 8043781
• 负责人: Peter A. Rice
• 金额: $ 8.35万
• 依托单位: UNIV OF MASSACHUSETTS MED SCH WORCESTER
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-04-05 至 2011-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8043781
• 关键词: Address; Amides; Asialoglycoprotein Receptor; Bacteria; Binding; C3bi; Cells; Cervical; Chemicals; Clinical; Complement; Complement 3; Complement 3b; Complement 4b; Complement Factor H; Cytidine Monophosphate N-Acetylneuraminic Acid; Data; Disease; Enzymes; Epithelial Cells; Esters; Exhibits; Galactose; Genes; Genital system; Gonorrhea; Hexoses; Immune system; Immunology; Infection; Knowledge; Label; Laboratories; Length; Light; Link; Macrophage-1 Antigen; Mediating; Neisseria; Neisseria gonorrhoeae; Neisseria meningitidis; Pathogenesis; Pathway interactions; Process; RNA Splicing; Regulation; Relative (related person); Research Personnel; Resistance; Rice; Role; Serum; Sialic Acids; Sialyltransferases; Side; Specificity; Structure; Surface; Urethra; Variant; Work; bactericide; base; cofactor; enhancing factor; genital infection; killings; lacto-N-neotetraose; lipooligosaccharide; mimicry; pathogen; porin; programs; receptor; sialylation; uptake

Neisseria gonorrhoeae is one of the two major pathogens involved in the majority of cases of sexually transmitted genital infection. Complement forms an important aspect of the innate immune system that impacts upon gonococcal infection. Prior work in our laboratory has shown that sialylation of gonococcal lipooligosaccharide (LOS) results in complement resistance by binding the host complement regulatory molecule, factor H. The porin molecule also binds factor H. In the first Specific Aim, we will investigate the role of an alternatively-spliced version of factor H, called factor H-like molecule 1 (FHL-1)in binding to gonococci and in regulating complement. Some strains of N. gonorrhoeae process complement (i.e. convert complement component-3 [C3b] to the inactivated form [iC3b]) and bind FHL-1, but not factor H. Cofactor activity of FHL-1 will be assessed using serum containing only FHL-1, but not intact factor H. Because both factor H and FHL-1 bind to cells, we will examine the roles of these two molecules in facilitating gonococcal attachment to immortalized cervical and urethral epithelial cells, in the second Specific Aim, three questions that pertain to LOS sialylation will be addressed. First, the specificity of factor H binding to gonococcal lacto- N-neotetraose (LNT) sialic acid, but not to meningococcai LNT sialic acid, will be examined. Porin (Por) influences binding of fH to gonococcal sialic acid. We will perform allelic exchange of porin molecules between the two species to examine the effect of porin on the sialylated LOS interactions with factor H that differs at baseline in the two neisserial species. Second, we will examine the determinants of the functional specificity of the LOS sialyltransferase (IsO enzyme in meningococci and gonococci by performing allelic exchanges of the Ist genes between the two species. Third, we will also determine why the efficiency of LOS sialylation differs between serum-sensitive (high sialic acid uptake) and "stably" serum-resistant (low sialic acid uptake) gonococci. This will be performed by examining the uptake of 3H-labeled CMP-NANA by isogenic gonococci differing only in their Lst enzymes. The possibility that Por modifies Lst activity will also be examined by performing allelic exchanges of the Por genes between high and low sialic acid incorporators. In the third Specific Aim, we will detail the linkages (amide versus ester) between C4 and LOS, the effects of hexose extension of the LOS on binding of C4 to LOS, and the impact of the bond formed between C4 and LOS on bactericidal killing.

淋病奈瑟氏菌是大多数性行为涉及的两种主要病原体之一 传播生殖器感染。补充构成了先天免疫系统的重要方面 对淋球菌感染的影响。我们实验室的先前工作表明淋球菌的溶解度 通过结合宿主补体调节性，脂肪糖（LOS）可导致补体抗性 分子，因子H。Porin分子还结合了因子H。在第一个特定目的中，我们将研究该因子。 因子H的作用，称为因子H样分子1（FHL-1）在结合中的作用 淋球菌和调节补体。一些淋病猪笼草的菌株补体补体（即转换 补体组件-3 [C3B]与灭活形式[IC3B]）并结合FHL-1，但没有因子H. cofactor FHL-1的活性将使用仅包含FHL-1的血清，但不是完整因素H进行评估。 因子H和FHL-1与细胞结合，我们将检查这两个分子在促进淋球菌中的作用 在第二个特定目的中，附着永生的宫颈和尿道上皮细胞，三个问题 将解决与Los los氨有关的。首先，因子H与淋球菌乳酸结合的特异性 将检查N-神经酸（LNT）唾液酸，但不适合脑膜炎lnt唾液酸。波林（POR） 影响FH与淋球菌唾液酸的结合。我们将执行孔蛋白分子的等位基因交换 在这两个物种之间检查孔蛋白对与因子h相互作用的影响 在两个奈瑟氏菌种中的基线时有所不同。其次，我们将检查功能的决定因素 通过进行等位基因，LOS溶酶体（脑膜炎球菌和淋球菌中的ISO酶）的特异性（ISO酶） 两种物种之间的IST基因的交换。第三，我们还将确定为什么 Los los氨基化在血清敏感（高唾液酸摄取）和“稳定”耐血清（低）之间有所不同（低 唾液酸摄取）淋球菌。这将通过检查3H标记的CMP-NANA的吸收来执行 等源性淋球菌仅在其LST酶方面有所不同。 POR修改LST活动的可能性也将 通过在高和低唾液酸之间进行POR基因的等位基因交换来检查 公司。在第三个特定目的中，我们将详细介绍C4和 LOS，LOS的己糖扩展对C4与LOS结合的影响以及键的影响 在杀菌性杀戮的C4和LOS之间形成。