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

• 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
• 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

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.

总结 在美国，每年有1500万女性受到尿路感染（UTI）的影响， 由于抗生素耐药性的高比率而变得更加困难。此外，UTI是高度复发性的。在20 40%的UTI发作之后是复发性UTI（rUTI），一些女性患有多达6或 每年更频繁。尿路致病性大肠杆菌（UPEC）是尿路感染的主要病原体。 UPEC分离株的抗生素耐药性正在上升，超广谱β-内酰胺酶的出现 产生氟喹诺酮耐药菌株是严重的公共卫生问题。1型皮利，尖端为 甘露糖结合FimH粘附素已被证明是膀胱定植和UTI发病所必需的 在多个小鼠模型中。FimH介导与膀胱表面的甘露糖基化尿斑蛋白结合， 促进定植和侵入膀胱细胞，在那里它们迅速复制成细胞内细菌 保护UPEC免受免疫细胞和抗生素的侵害。此外，FimH促进了以下能力： UPEC在GIT中建立一个储库，从那里他们可以通过尿道周围上行接种UTI 进入膀胱。虽然UPEC是遗传可变的，但FimH是核心E.大肠杆菌基因组，虽然 已经发现在1型操纵子中具有突变的罕见菌株。针对FimH的免疫可预防 UPEC UTI在鼠和猴膀胱炎模型中的应用以及基于FimH的疫苗已被FDA允许用于 多药耐药UPEC患者。在动物模型中，保护作用是抗体介导的，如FimH- 在受保护动物的尿液中发现了特异性IgG抗体， 转移有趣的是，在有症状的UTI时，肠道中的UPEC丰度增加，这表明 肠道定殖是鲁蒂循环中的关键步骤。此外，该提案中的研究表明， 针对FimH的抗体应答可减少肠道的UPEC定殖。根据这些调查结果，这项建议 解决了抗FimH诱导的抗体可以通过两种不同机制对抗鲁蒂的假设：i） 阻止UPEC结合至泌尿上皮;和ii）干扰GIT的UPEC定殖，从而 降低UPEC进入泌尿道的可能性。本提案的目的是：（一）确定 针对FimCH粘膜接种如何减少UPEC肠道定殖（目的1）; ii）利用疫苗诱导的B 分离抗FimH的单克隆抗体（mAb）并确定其表位特异性的细胞应答（Aim 2）; 和iii）在GIT定殖和膀胱炎的小鼠模型中使用这些mAb以阐明 保护（目标3）。该研究计划将揭示抗FimH抗体可能发挥作用的机制 通过直接阻断膀胱结合和间接干扰UPEC GIT定植来预防UTI。 这些结果将为影响数百万rUTIs患者的尿路病原体的合理靶向提供信息。在 此外，我们的方法能够快速产生可用于治疗的抗UPEC人mAb 和诊断。