Calprotectin modulates Group B streptococcal colonization and disease

钙卫蛋白调节 B 族链球菌定植和疾病

• 批准号: 10190492
• 负责人: Kelly S Doran
• 金额: $ 25.62万
• 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: 2021-03-16 至 2023-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10190492
• 关键词: Address; Amniotic Fluid; Bacterial Infections; Binding; Bioavailable; Birth; Cells; Complement; Cytoplasm; Cytosol; Data; Disease; Disease Progression; Epithelial; Essential Genes; Female; Fetal Development; Gene Combinations; Genes; Genetic Transcription; Goals; Growth; Homeostasis; Host Defense; Host Defense Mechanism; Immune; Immune signaling; Immunologics; In Vitro; Individual; Infant; Infection; Inflammation; Inflammatory; Inflammatory Response; Invaded; Ions; Knockout Mice; Leukocyte L1 Antigen Complex; Libraries; Manganese; Mediating; Mediator of activation protein; Metals; Molecular; Mouse Strains; Mucous Membrane; Mus; Neutrophil Infiltration; Neutrophilic Infiltrate; Newborn Infant; Nutritional Immunity; Outcome; Permeability; Pregnancy; Pregnancy Complications; Pregnant Women; Premature Birth; Premature Labor; Process; Production; Publishing; Risk; Role; S100A8 gene; S100A9 gene; Signal Transduction; Site; Spontaneous abortion; Streptococcal Infections; Streptococcus Group B; Stress; System; Tissues; Up-Regulation; Uterus; Vagina; Virulence; Woman; Zinc; adverse pregnancy outcome; amniotic cavity; chelation; combat; cytokine; defense response; dimer; host colonization; in vivo; in vivo Model; insight; intrauterine infection; mouse model; mutant; neutralizing antibody; neutrophil; opportunistic pathogen; pathogen; protein complex; reproductive tract; response; stillbirth; transmission process; transposon sequencing; uptake; vaginal mucosa; zinc-binding protein

PROJECT SUMMARY During bacterial infection, the host produces numerous factors that limit metals at the site of infection in a process termed nutritional immunity. The goal of this proposal is to identify mechanisms utilized by Group B Streptococcus (GBS) to evade nutritional immunity in order to persist within the vaginal mucosa and cause intrauterine infection. GBS asymptomatically colonizes the vaginal tract of 25-30% of healthy women but can ascend and preterm labor or birth, miscarriage, or stillbirth. Intrauterine infection leads to massive neutrophil influx and inflammation, where 50% of the cytoplasm of infiltrating neutrophils is calprotectin, a protein complex that upon release sequesters metal ions. During infection, GBS encounters high concentrations of calprotectin and must be able to overcome this stress, but the interaction of GBS with host calprotectin remains unknown. Our preliminary data show that calprotectin can inhibit GBS growth and studies utilizing a newly constructed saturated GBS transposon (Tn) sequencing mutant library revealed significantly underrepresented mutants in zinc transport systems following calprotectin exposure. We hypothesize that zinc transport machinery is important for GBS survival during calprotectin stress, and further that calprotectin may serve as a pro-inflammatory effector molecule, acting to compromise barrier function during GBS infection. This proposal seeks to elucidate the molecular mechanisms by which GBS overcomes calprotectin-mediated nutritional immunity in the female reproductive tract, and the role of calprotectin in ascending infection. These questions will be addressed with both in vitro and in vivo models of GBS vaginal colonization and ascending infection in the following specific aims: AIM 1: Characterize and identify the molecular determinants utilized by GBS to combat nutritional immunity during vaginal colonization; AIM 2: Determine the role of calprotectin as a modulator of reproductive tract inflammation and barrier integrity during GBS infection. These studies are the first to examine GBS metal homeostasis and the pro-inflammatory effects of calprotectin during GBS vaginal colonization, which will provide fundamental insights toward our understanding of GBS mucosal persistence and transmission to the vulnerable newborn. from the vagina into the uterus and invade the amniotic cavity, leading to inflammation, tissue damage, adverse pregnancy outcomes, including

项目总结 在细菌感染期间，宿主产生许多因素，限制感染部位的金属 这一过程称为营养免疫。该提案的目标是确定B组使用的机制 链球菌(GBS)逃避营养免疫，以便在阴道粘膜内持续存在，并引起 宫内感染。GBS在25%-30%的健康女性的阴道中无症状地定植，但可以 上升 以及早产、分娩、流产或死产。宫内 感染导致中性粒细胞大量涌入和炎症，其中50%的细胞质正在渗入 中性粒细胞是钙保护素，这是一种蛋白质复合体，在释放时会隔离金属离子。在感染期间，GBS 遇到高浓度的钙保护素，必须能够克服这种压力，但 含有宿主钙保护素的GBS仍不清楚。我们的初步数据显示，钙保护素可以抑制GBS 利用新构建的饱和GBS转座子(TN)测序突变体文库的生长和研究 在钙保护素暴露后，发现锌转运系统中的突变体明显不足。我们 假设锌运输机械在钙保护素应激期间对GBS的存活很重要，并进一步 这种钙保护素可能作为促炎效应分子发挥作用，损害屏障功能。 在GBS感染期间。这一建议试图阐明GBS克服的分子机制。 钙保护素介导的女性生殖道营养免疫及其在生殖系统中的作用 上行性感染。这些问题将通过GBS阴道的体外和体内模型来解决 下列具体目标中的定居和上行感染：目标1：确定和确定 GBS在阴道定植期间利用分子决定因素对抗营养免疫；目的2： 确定钙保护素在生殖道炎症和屏障完整性中的调节作用 GBS感染。这些研究首次检测了GBS的金属动态平衡和促炎作用。 在GBS阴道定植过程中的钙保护素，这将为我们的 对GBS粘膜持久性和对易感新生儿的传播的了解。 从阴道进入子宫并侵入羊膜腔，导致炎症，组织损伤， 不良妊娠结局，包括