Development of a mucosal vaccine to prevent Clostridium difficile infection using papilloma pseudovirus as a vector.

使用乳头状瘤假病毒作为载体开发粘膜疫苗以预防艰难梭菌感染。

• 批准号: 10213890
• 负责人: Katherine L. Knight
• 金额: $ 50.23万
• 依托单位: LOYOLA UNIVERSITY CHICAGO
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-08-01 至 2023-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10213890
• 关键词: Adjuvant; Affect; Amino Acid Sequence; Animal Disease Models; Antibiotic Therapy; Antibiotics; Antibodies; Antibody Formation; Antibody Response; Binding; C-terminal; Capsid; Cell surface; Cessation of life; Clinical; Clinical Trials; Clinical Trials Data Monitoring Committees; Clostridium difficile; DNA Viruses; Data; Development; Diarrhea; Disease; Environment; Epithelial; Epithelial Cells; Epithelium; FDA approved; Feces; Flagellin; Goals; Gold; Grant; Hamsters; Health Care Costs; Healthcare; Human; Human papillomavirus HPV L1 protein; Immunity; Immunize; Immunoglobulin A; Immunologic Memory; Incidence; Infection; Intestinal Mucosa; Intestines; L2 viral capsid protein; Life; Membrane Proteins; Memory; Mesocricetus auratus; Methods; Minor; Molecular Weight; Mucous Membrane; Mus; Nosocomial Infections; Oral; Papilloma; Papillomavirus; Pathogenesis; Patients; Phase; Phase II/III Clinical Trial; Phase II/III Trial; Plasmids; Probability; Proteins; Pseudomembranous Colitis; Recurrent disease; Reporting; Reproduction spores; Resistance; Surface; Surface Antigens; Symptoms; Targeted Toxins; Testing; Toxin; Vaccinated; Vaccination; Vaccines; Virulence Factors; Virus-like particle; alpha Toxin; anti-IgA; antitoxin; commensal microbes; disease transmission; efficacy testing; gut colonization; gut microbiota; health care settings; immunogenic; improved; in vivo; inhibiting antibody; mucosal vaccine; neutralizing antibody; particle; pathogen; prevent; programs; protein B; receptor binding; response; transmission process; vaccine development; vaccine efficacy; vector; vector vaccine

Abstract Clostridium difficile is a major cause of diarrhea in health care settings, with one-half million cases of infection, annually. Clostridium difficile infection and disease (CDI) usually occurs after antibiotic treatment, which eliminates much of the intestinal commensal microbiota and provides C. difficile the opportunity to colonize the gut. If the colonizing C. difficile produces toxins, many patients develop CDI and suffer from symptoms ranging from diarrhea to life-threatening pseudomembranous colitis. The incidence of CDI is on the rise, in large part because of increased use of antibiotics. Further, CDI recurs in ~20% of treated patients, making this a serious and expensive disease, for which there is no cure and no effective approved vaccine. The goal of this proposal is to develop a protective vaccine to prevent CDI and also, its transmission in the health care environment. While a few C. difficile vaccines are in Phase II/III clinical trials, they target the toxins, but will not prevent colonization of C. difficile in the intestinal mucosa, nor its transmission. We think that the optimal protective vaccine would be one that generates a strong mucosal IgA antibody response against toxins, and also one that prevents colonization of C. difficile. Papillomaviruses are small DNA viruses in which the major capsid protein, L1, assembles with the minor capsid protein, L2 into virus-like particles (VLP). These VLPs infect mucosal surfaces, are not infectious but are strongly immunogenic, making them ideal vectors for mucosal vaccines. We have developed papilloma pseudoviruses (PsV) from capsid proteins L1 and L2, that contain plasmids expressing the receptor binding domain (RBD) of the C. difficile toxins A and B, and we have preliminary data showing that these vaccines can induce neutralizing mucosal IgA and protect mice from challenge by C. difficile. In Aim 1, we will develop PsV expressing RBD of toxins A, B (from different strains) and binary toxin. We will immunize them in mice and hamsters. We will identify an adjuvant that will increase the mucosal Ab response and generate long-term immunologic memory in mice and hamsters, the gold standard for CDI animal models. In Aim 2, we will generate PsV expressing surface molecules FliD or high molecular weight SLP, molecules that will affect colonization, and determine if these vaccines can induce antibodies that inhibit colonization of C. difficile. In Aim 3, we will vaccinate mice and hamsters with a mixture of all the PsV and challenge with toxogenic C. difficile spores from different strains to determine if CDI and colonization of C. difficile are prevented. If successful, the mucosal vaccine will generate a robust neutralizing mucosal IgA response against both toxins and the surface antigens FliD and SLP. Such a vaccine would make a major contribution to improving the health care of thousands of patients in health care settings, and save billions of dollars in health care costs.

抽象的 艰难梭菌是医疗机构中腹泻的主要原因，有五十万感染病例， 每年。艰难梭菌感染和疾病（CDI）通常发生在抗生素治疗后，这 消除大部分肠道共生微生物群，并为艰难梭菌提供定植机会 肠道。如果定植的艰难梭菌产生毒素，许多患者会出现 CDI 并出现症状 范围从腹泻到危及生命的伪膜性结肠炎。 CDI 的发病率呈上升趋势， 很大一部分原因是抗生素使用的增加。此外，约 20% 的接受治疗的患者会复发 CDI，这使得 这是一种严重且昂贵的疾病，无法治愈，也没有有效的批准疫苗。此举的目标 建议开发一种保护性疫苗来预防 CDI 及其在医疗保健中的传播 环境。虽然一些艰难梭菌疫苗正处于 II/III 期临床试验，它们针对的是毒素，但会 不能阻止艰难梭菌在肠粘膜中的定植，也不能阻止其传播。我们认为最优的 保护性疫苗将是一种能够产生针对毒素的强烈粘膜 IgA 抗体反应的疫苗，并且 一种可以防止艰难梭菌定植的药物。乳头瘤病毒是小型 DNA 病毒，其中主要 衣壳蛋白 L1 与次要衣壳蛋白 L2 组装成病毒样颗粒 (VLP)。这些VLP 感染粘膜表面，不具有传染性，但具有很强的免疫原性，使其成为理想的载体 粘膜疫苗。我们从衣壳蛋白 L1 和 L2 中开发出乳头状瘤假病毒 (PsV)， 含有表达艰难梭菌毒素 A 和 B 的受体结合域 (RBD) 的质粒，我们有 初步数据表明，这些疫苗可以诱导中和粘膜 IgA 并保护小鼠免受 艰难梭菌的挑战。在目标 1 中，我们将开发表达毒素 A、B（来自不同毒株）的 RBD 的 PsV 和二元毒素。我们将对小鼠和仓鼠进行免疫接种。我们将确定一种可以增加 粘膜抗体反应并在小鼠和仓鼠中产生长期免疫记忆，黄金 CDI 动物模型标准。在目标 2 中，我们将生成表达表面分子 FliD 或 high 分子量 SLP、影响定植的分子，并确定这些疫苗是否可以诱导 抑制艰难梭菌定植的抗体。在目标 3 中，我们将为小鼠和仓鼠接种疫苗 将所有 PsV 混合并用来自不同菌株的有毒艰难梭菌孢子进行攻击，以确定是否存在 CDI 并防止艰难梭菌的定植。如果成功，粘膜疫苗将产生强大的 中和针对毒素和表面抗原 FliD 和 SLP 的粘膜 IgA 反应。这样的疫苗 将为改善医疗机构中数千名患者的医疗保健做出重大贡献， 并节省数十亿美元的医疗保健费用。