Characterizing the Contribution of the Group B Streptococcal Surface Adhesin BspC Interaction with Host Vimentin to Disease and Colonization

表征 B 族链球菌表面粘附素 BspC 与宿主波形蛋白相互作用对疾病和定植的贡献

• 批准号: 10312484
• 负责人: Haider Syed Manzer
• 金额: $ 3.4万
• 依托单位: UNIVERSITY OF COLORADO DENVER
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2023-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10312484
• 关键词: Address; Adherence; Adult; Alanine; Amino Acids; Antibiotic Therapy; Bacteria; Bacterial Adhesins; Bacterial Infections; Bacterial Meningitis; Binding; Binding Sites; Biological Assay; Birth; Blood; Blood - brain barrier anatomy; Blood Vessels; Brain; CXCL1 gene; CXCL2 gene; Cell Communication; Cell Line; Cells; Central Nervous System Diseases; Cerebral Ischemia; Cervical; Cervix Uteri; Characteristics; Chromosomes; Cognitive deficits; Complement; Data; Development; Disease; Disease Progression; Endometritis; Endothelial Cells; Endothelium; Enzyme-Linked Immunosorbent Assay; Epithelial Cells; Etiology; Exhibits; Family; Female; Female genitalia; Fetus; Gastrointestinal tract structure; Human; Hydrophobicity; I-antigen; IL6 gene; IL8 gene; Immune response; In Vitro; Infant; Infection; Inflammation; Inflammatory; Interleukin-1 beta; Intermediate Filament Proteins; Invaded; Knockout Mice; Length; Ligand Binding; Measures; Meningeal; Meningitis; Molecular; Mus; Mutation; Neonatal meningitis; Neuraxis; Neurologic; Newborn Infant; Pathogenesis; Plasmids; Point Mutation; Population; Pregnancy; Pregnant Women; Premature Birth; Premature Labor; Proteins; Publications; Quantitative Reverse Transcriptase PCR; Recombinants; Role; Seizures; Signal Transduction; Site-Directed Mutagenesis; Streptococcus Group B; Surface; Survivors; System; Tertiary Protein Structure; Testing; Therapeutic; Tissues; Transcript; Uterus; Vagina; Vimentin; Woman; blood-brain barrier penetration; brain endothelial cell; cell type; design; epithelial to mesenchymal transition; experimental study; in silico; in utero; in vivo; in vivo Model; insight; intraamniotic infection; intrauterine infection; mortality; mouse model; mutant; neonatal bacterial meningitis; neonatal infection; neonate; pathogenic bacteria; placental membrane; prevent; reproductive tract; screening; transmission process; treatment strategy; urogenital tract; vaccine access; vector; yeast two hybrid system

PROJECT SUMMARY Group B Streptococcus (GBS, also known as Streptococcus agalactiae) is a Gram-positive, -hemolytic bacterium normally found in the human gastrointestinal and urogenital tracts. GBS remains a leading cause of invasive disease in newborns and certain adult populations including pregnant women. The development of GBS disease is initiated by the asymptomatic colonization of the female genital tract and during pregnancy can be associated with chorioamnionitis, puerperal endometritis and preterm labor. Approximately 20-30% of healthy women are colonized rectovaginally with GBS; the majority of infants born to these women will themselves become colonized with the bacterium. Newborn infection also results from ascending infection of the bacterium through the placental membranes to initiate infection in utero. GBS is the principle etiologic agent of neonatal bacterial meningitis, and GBS meningeal infection results in 10-15% mortality despite antibiotic treatment. Additionally, up to 40% of survivors develop permanent neurological sequelae, including cognitive defects, seizure activity, and cerebral ischemia. To access the central nervous system (CNS) and cause meningitis blood-borne GBS must penetrate the blood-brain barrier (BBB); however, little is known about the very first and crucial interaction between GBS and the BBB that initiates bacterial crossing and disease progression. This proposal seeks to characterize the role of a newly identified GBS Antigen I/II family adhesin, BspC, to the pathogenesis of colonization and CNS disease. We have recently determined that BspC promotes attachment to BBB endothelium and contributes to the development of GBS meningitis. Further we have discovered that BspC interacts directly with vimentin, a widely distributed intermediate filament protein found in blood vessel endothelial cells. Thisproposal seeks toidentify the region on BspC that interacts with vimentin, and to characterize the role of this interaction in GBS meningitis and colonization of the female reproductive tract. I hypothesize that the binding region is contained within the globular variable domain (V- domain) of BspC and contributes to both GBS meningitis and vaginal colonization/ascending infection. These hypotheses will be addressed with both in vitro and in vivo models of BBB penetration and vaginal colonization in the following specific aims: Aim 1: Identify the critical regions and amino acids required for BspC V-domain- vimentin interaction; Aim 2: Characterize the role of BspC and vimentin in the female reproductive tract. These data will clarify the crucial role of Antigen I/II proteins to GBS colonization and disease and provide fundamental mechanistic insights that may inform new treatment strategies to prevent colonization and ultimately bacterial meningitis.

项目概要 B 族链球菌（GBS，也称为无乳链球菌）是一种革兰氏阳性、-溶血性链球菌 通常存在于人类胃肠道和泌尿生殖道中的细菌。 GBS 仍然是导致 新生儿和某些成年人（包括孕妇）的侵袭性疾病。的发展 GBS 疾病是由女性生殖道的无症状定植引发的，在怀孕期间可以 与绒毛膜羊膜炎、产后子宫内膜炎和早产有关。大约20-30% 健康女性的直肠阴道内有 GBS 定植；这些妇女所生的大多数婴儿将 它们本身就被细菌定殖。新生儿感染也由上行感染引起 细菌通过胎盘膜在子宫内引发感染。 GBS是主要病因 新生儿细菌性脑膜炎的病原体，GBS 脑膜感染导致 10-15% 的死亡率，尽管 抗生素治疗。此外，高达 40% 的幸存者会出现永久性神经系统后遗症，包括 认知缺陷、癫痫发作和脑缺血。进入中枢神经系统（CNS）并 引起脑膜炎的血源性GBS必须穿透血脑屏障（BBB）；然而，人们对此知之甚少 GBS 和 BBB 之间最初也是最重要的相互作用，引发细菌交叉和疾病 进展。该提案旨在描述新鉴定的 GBS 抗原 I/II 家族粘附素的作用， BspC，定植和中枢神经系统疾病的发病机制。我们最近确定 BspC 促进 BBB 内皮的附着并促进 GBS 脑膜炎的发展。进一步我们 发现 BspC 直接与波形蛋白相互作用，波形蛋白是一种广泛分布的中间丝蛋白 存在于血管内皮细胞中。该提案旨在确定 BspC 上与 波形蛋白，并描述这种相互作用在 GBS 脑膜炎和女性定植中的作用 生殖道。我假设结合区域包含在球状可变域（V- BspC 的结构域），并导致 GBS 脑膜炎和阴道定植/上行感染。这些 将通过 BBB 渗透和阴道定植的体外和体内模型来解决假设 目标 1：确定 BspC V 结构域所需的关键区域和氨基酸 波形蛋白相互作用；目标 2：表征 BspC 和波形蛋白在女性生殖道中的作用。这些 数据将阐明抗原 I/II 蛋白对 GBS 定植和疾病的关键作用，并提供 基本的机制见解可以为防止定植和预防新的治疗策略提供信息 最终导致细菌性脑膜炎。