Harnessing Antibody Responses to Prevent and Treat Urinary Tract Infections

利用抗体反应预防和治疗尿路感染

基本信息

批准号：
10523527
负责人：
Andrew Leon Kau
金额：
$ 62.77万
依托单位：
WASHINGTON UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-11-10 至 2026-10-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10523527
关键词：
Activities of Daily Living Address Adherence Affect Affinity Animal Model Animals Antibiotic Resistance Antibiotic Therapy Antibiotics Antibodies Antibody Formation Antibody Response Antibody Specificity Area B-Lymphocytes Bacterial Adhesins Binding Bladder Blocking Antibodies Cell Separation Cells Coal Communicable Diseases Communities Cystitis Data Development Diagnostic Distal Epithelium Epitopes Equilibrium Escherichia coli Extended-spectrum β-lactamase Gastrointestinal tract structure Generations Genome Gnotobiotic Host Defense Mechanism Human Immune Immune System Diseases Immunization Immunoglobulin G Immunoglobulin-Secreting Cells Impairment Infection prevention Invaded Light Mannose Mannosides Mediating Modeling Molecular Conformation Monkeys Monoclonal Antibodies Mucous Membrane Multi-Drug Resistance Mus Mutation Operon Oral Administration Passive Immunization Pathogenesis Pathogenicity Patients Persons Phase Ia/Ib Clinical Trial Pilum Prevalence Prevention Production Public Health Recombinants Recurrence Research Resistance Resolution Role Serinus Signal Transduction Specificity Surface Tertiary Protein Structure Testing Therapeutic Therapeutic Uses Thinking Time United States Urethra Urinary tract Urinary tract infection Urine Uropathogen Uropathogenic E. coli Vaccinated Vaccination Vaccines Virus Diseases Woman ascending urinary tract infection bacterial community cancer therapy combat design effectiveness testing fluoroquinolone resistance gut colonization gut microbiota human monoclonal antibodies humanized monoclonal antibodies in vivo microbial community mouse model mucosal vaccination prevent receptor resistant strain response

项目摘要

SUMMARY Urinary tract infections (UTIs) affect 15 million women in the United States every year and treatment for UTIs is becoming more difficult due to high rates of antibiotic resistance. Further, UTIs are highly recurrent. Between 20 and 40% of UTI episodes are followed by recurrent UTIs (rUTIs), with some women suffering as many as 6 or more recurrences per year. Uropathogenic Escherichia coli (UPEC) is the major causative agent of UTIs. Antibiotic resistance within UPEC isolates is rising, and the emergence of extended-spectrum beta-lactamase producing and fluoroquinolone resistant strains is a serious public health concern. Type 1 pili, tipped with the mannose binding FimH adhesin have been shown to be essential for bladder colonization and UTI pathogenesis in multiple mouse models. FimH mediates binding to mannosylated uroplakins lining the bladder surface to facilitate colonization and invasion into bladder cells where they rapidly replicate into intracellular bacterial communities that protect UPEC from immune cells and antibiotics. In addition, FimH facilitates the ability of UPEC to establish a reservoir in the GIT, from where they can seed UTIs by ascending from the periurethral area into the bladder. While UPEC are genetically variable, FimH is part of the core E. coli genome, although rare strains have been found with mutations in the type 1 operon. Immunization against FimH protects against UPEC UTI in murine and monkey cystitis models and a FimH-based vaccine has been allowed by the FDA for patients suffering from multi-drug resistant UPEC. In animal models, protection is antibody-mediated, as FimH- specific IgG antibodies are found in the urine from protected animals and can protect from UTI through passive transfer. Intriguingly, UPEC abundance in the gut is increased at the time of symptomatic UTI, suggesting that gut colonization is a key step in the rUTI cycle. Additionally, studies in this proposal show that eliciting a mucosal antibody response against FimH can reduce UPEC colonization of the gut. In light of these findings, this proposal addresses the hypothesis that anti-FimH induced antibodies can combat rUTI by two distinct mechanisms: i) prevention of UPEC binding to the uroepithelium; and ii) interference with UPEC colonization of the GIT, thereby lowering the likelihood of UPEC introduction into the urinary tract. The aims of this proposal are to: i) determine how mucosal vaccination against FimCH reduces UPEC gut colonization (Aim 1); ii) exploit vaccine induced B cell responses to isolate monoclonal antibodies (mAbs) to FimH and determine their epitope specificity (Aim 2); and iii) use these mAbs in mouse models of GIT colonization and cystitis in order to elucidate mechanisms of protection (Aim 3). The research plan will unravel the mechanisms by which anti-FimH antibodies may function to prevent UTIs by directly blocking bladder binding and indirectly by interfering with UPEC GIT colonization. These results will inform the rational targeting of the uropathogens that affect millions of people with rUTIs. In addition, our approach enables the rapid generation of anti-UPEC human mAbs that can be used for therapeutics and diagnostics.

概括尿路感染 (UTI) 每年影响美国 1500 万女性，尿路感染的治疗方法由于抗生素耐药性高，变得更加困难。此外，尿路感染的复发率很高。 20 之间 40% 的尿路感染发作后会出现复发性尿路感染 (rUTI)，一些女性遭受多达 6 或每年复发次数更多。尿路致病性大肠杆菌 (UPEC) 是尿路感染的主要病原体。 UPEC 分离株内的抗生素耐药性正在上升，并且出现了超广谱 β-内酰胺酶产生氟喹诺酮类药物和耐药菌株是一个严重的公共卫生问题。 1 型菌毛，尖端带有甘露糖结合 FimH 粘附素已被证明对于膀胱定植和 UTI 发病机制至关重要在多种鼠标模型中。 FimH 介导与膀胱表面内衬的甘露糖化尿斑蛋白的结合促进膀胱细胞的定植和侵袭，并在膀胱细胞中快速复制成细胞内细菌保护 UPEC 免受免疫细胞和抗生素侵害的社区。此外，FimH 还促进了以下能力： UPEC 在胃肠道中建立一个储存库，从那里他们可以通过尿道周围上升来传播尿路感染区域进入膀胱。虽然 UPEC 存在遗传变异，但 FimH 是核心大肠杆菌基因组的一部分，尽管已发现罕见菌株的 1 型操纵子发生突变。 FimH 免疫可预防 FDA 已允许在小鼠和猴膀胱炎模型中使用 UPEC UTI 和基于 FimH 的疫苗患有多重耐药 UPEC 的患者。在动物模型中，保护是抗体介导的，如 FimH- 在受保护动物的尿液中发现了特异性 IgG 抗体，可以通过被动方式预防尿路感染转移。有趣的是，在出现症状性尿路感染时，肠道中的 UPEC 丰度会增加，这表明肠道定植是 rUTI 周期的关键步骤。此外，该提案中的研究表明，引起粘膜针对 FimH 的抗体反应可以减少 UPEC 在肠道的定植。鉴于这些发现，本提案提出了抗 FimH 诱导抗体可以通过两种不同机制对抗 rUTI 的假设：i) 防止 UPEC 与尿路上皮结合； ii) 干扰 UPEC 在 GIT 上的定植，从而降低 UPEC 进入尿路的可能性。该提案的目的是： i) 确定针对 FimCH 的粘膜疫苗接种如何减少 UPEC 肠道定植（目标 1）； ii) 利用疫苗诱导 B 细胞反应以分离 FimH 的单克隆抗体 (mAb) 并确定其表位特异性（目标 2）； iii) 在胃肠道定植和膀胱炎小鼠模型中使用这些单克隆抗体，以阐明其机制保护（目标 3）。该研究计划将揭示抗 FimH 抗体发挥作用的机制通过直接阻断膀胱结合和间接干扰 UPEC GIT 定植来预防尿路感染。这些结果将为合理靶向影响数百万 rUTI 患者的尿路病原体提供信息。在此外，我们的方法能够快速生成可用于治疗的抗 UPEC 人类单克隆抗体和诊断。