Defining the impact of zinc on Streptococcus agalactiae biofilm and colonization

确定锌对无乳链球菌生物膜和定植的影响

• 批准号: 10571912
• 负责人: Ryan S Doster
• 金额: $ 18.54万
• 依托单位: UNIVERSITY OF LOUISVILLE
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-03-09 至 2025-02-28
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10571912
• 关键词: Academic Medical Centers; Adult; Area; Bacterial Infections; Bacterial Physiology; Cells; Communicable Diseases; Complement; Core Facility; Data; Development; Epithelial Cells; Epithelium; Event; Female; Fetal Membranes; Future; Genetic; Genetic Transcription; Genomics; Glucose; Goals; Human; Immune response; Impairment; In Vitro; Infection; Inflammatory Response; Innate Immune Response; Link; Medicine; Mentors; Mentorship; Microbial Biofilms; Microscopy; Modeling; Morbidity - disease rate; Mus; Mutagenesis; Newborn Infant; Nutrient; Pathogenesis; Pathway interactions; Pediatrics; Perinatal; Perinatal Infection; Physicians; Pregnancy; Pregnant Women; Premature Birth; Premature Labor; Production; Program Development; Regulator Genes; Regulatory Pathway; Research; Research Personnel; Resolution; Risk; Risk Factors; Role; Scholarship; Scientist; Stimulus; Streptococcal Infections; Streptococcus Group B; Supplementation; Techniques; Technology; Testing; Tissue membrane; Tissues; United States; Vagina; Woman; Work; Zinc; Zinc deficiency; Zinc supplementation; career; career development; clinical training; dietary; early onset; host colonization; human model; in vitro Model; in vivo; infection risk; innovation; instructor; instrument; intraamniotic infection; intrauterine infection; microbial host; mortality; mouse model; multidisciplinary; mutant; neonatal infection; neonatal sepsis; novel strategies; organ on a chip; pathogen; premature; prevent; reproductive tract; response; stillbirth; transcriptome; transcriptomics; zinc-binding protein

Project Summary During pregnancy, zinc deficiency is associated with an increased risk of infection. Streptococcus agalactiae, also known as Group B Streptococcus (GBS), colonizes 20-30% of pregnant women. GBS vaginal colonization increases the risk for stillbirth, preterm labor, and neonatal sepsis. One strategy that GBS may use to stably colonize the reproductive tract is to produce biofilm, and we have found that GBS biofilm production is suppressed in the presence of zinc. This proposal tests the hypothesis that GBS biofilm production is negatively regulated by zinc, and this biofilm contributes to stable colonization of host tissues by limiting innate immune responses against GBS. To test this hypothesis, Aim 1 will use mutagenesis and transcriptomic approaches to identify genetic pathways regulating GBS biofilm. Aim 2 will define the impact of zinc-regulated biofilm at the host-microbial interface by evaluating GBS mutants lacking cadD, a zinc efflux transporter, which results in impaired biofilm production. We will examine these interactions using in vitro models of human vaginal epithelial cells, explanted human fetal membranes, and an Instrumented Fetal Membrane Organ on a Chip (IFMOC) model under conditions that modify zinc availability. Aim 3 will use a mouse vaginal colonization model to define how the zinc transporter, cadD, impacts vaginal colonization in settings of zinc deficiency or supplementation. Completion of these Aims will shed new light on how zinc impacts GBS-host interactions that culminate in colonization (and infection) of the reproductive tract. Dr. Ryan Doster is an Instructor in the Division of Infectious Diseases at Vanderbilt University Medical Center. His past work investigated gestational tissue innate immune responses to infection. This project will expand his research focus to mechanisms of GBS colonization. This project complements Dr. Doster’s clinical training in pediatrics and adult infectious diseases medicine. Under the mentorship of Dr. David Aronoff, Dr. Jennifer Gaddy, and a multidisciplinary Scholarship Oversight Committee, Dr. Doster will master techniques including bacterial mutagenesis, transcriptomics, and modeling infection within the reproductive tract to determine how zinc alters bacterial physiology and pathogenesis. Vanderbilt offers cutting-edge technology and expertise in these areas through Vanderbilt Technologies for Advanced Genomics and other shared research core facilities. These studies and a strong career development program will prepare Dr. Doster for transition to an independent researcher investigating the pathogenesis of bacterial infections during pregnancy.

项目摘要 在怀孕期间，锌缺乏与感染风险增加有关。无乳链球菌， 也称为B族链球菌（GBS），在20-30%的孕妇中定植。GBS阴道定植 增加死胎、早产和新生儿败血症的风险。GBS可以使用的一种策略是稳定 定植生殖道是为了产生生物膜，我们发现GBS生物膜的产生是 在锌的存在下被抑制。该提议检验了GBS生物膜产生是 负调控的锌，这种生物膜有助于稳定定植的宿主组织，通过限制先天 对GBS的免疫反应。为了验证这一假设，Aim 1将使用诱变和转录组学方法， 方法来确定调节GBS生物膜的遗传途径。目标2将定义锌调控的影响 通过评估缺乏cadD的GBS突变体在宿主-微生物界面的生物膜，cadD是一种锌外排转运蛋白， 导致生物膜产生受损。我们将使用体外模型研究这些相互作用， 阴道上皮细胞、分离的人胎膜和仪器化的胎膜器官， 芯片（IFMOC）模型的条件下，修改锌的可用性。Aim 3将使用小鼠阴道定植 模型来定义锌转运蛋白cadD如何影响缺锌环境中的阴道定植， 补充。这些目标的完成将为锌如何影响GBS-宿主相互作用提供新的线索， 最终在生殖道定植（和感染）。 博士Ryan Doster是范德比尔特大学医学中心传染病部的讲师。 他过去的工作研究了妊娠组织对感染的先天免疫反应。这个项目将扩大他的 研究重点是GBS定植机制。该项目补充了Doster博士的临床培训， 儿科和成人传染病医学。在大卫·阿罗诺夫博士的指导下， Gaddy和多学科奖学金监督委员会，Doster博士将掌握的技术，包括 细菌诱变，转录组学和生殖道内的感染建模，以确定如何 锌改变细菌的生理学和发病机制。范德比尔特提供尖端技术和专业知识， 这些领域通过范德比尔特先进基因组技术和其他共享的研究核心 设施这些研究和强大的职业发展计划将为Doster博士过渡到 独立研究者调查怀孕期间细菌感染的发病机理。