Broad spectrum Shigella subunit vaccine based on conserved proteins

基于保守蛋白的广谱志贺氏菌亚单位疫苗

• 批准号: 10549775
• 负责人: Marcela F Pasetti
• 金额: $ 53.13万
• 依托单位: UNIVERSITY OF MARYLAND BALTIMORE
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-02-04 至 2026-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10549775
• 关键词: 5 year old; Adjuvant; Adult; Affect; Animal Model; Antibiotic Resistance; Antibiotics; Antibodies; Antigens; Antimicrobial Resistance; Area; Attenuated; Cavia; Cell Culture Techniques; Cell-Free System; Cells; Child; Clinical; Clinical Research; Country; Data; Day center care; Developed Countries; Development; Diarrhea; Disease; Disease Outbreaks; Dysentery; Epidemiology; Evaluation; Goals; Growth; Human; Human Milk; IgG1; Immune Sera; Immunity; Immunization; Immunoglobulin G; Immunologics; Impaired cognition; In Vitro; Incidence; Infant; Infection; Inflammatory; Institution; Interruption; Intramuscular; Invaded; Laboratories; Life; Medical; Methods; Military Personnel; Modeling; Monoclonal Antibodies; Mothers; Mucous Membrane; Multi-Drug Resistance; Mus; Natural Immunity; Nature; O Antigens; Oral; Organism; Oryctolagus cuniculus; Phase; Placenta; Plasmids; Polysaccharides; Positioning Attribute; Production; Protein Biosynthesis; Proteins; Public Health; Reporting; Resources; Risk; Role; Rotavirus; Serotyping; Serum; Severities; Shigella; Shigella Infections; Shigella Vaccines; Subunit Vaccines; System; T cell response; Technology; Testing; Translating; Type III Secretion System Pathway; Vaccine Antigen; Vaccines; Virulence; Virulent; Vulnerable Populations; Work; aluminum sulfate; bioweapon; burden of illness; clinical development; clinical translation; clinically relevant; cost; diarrheal disease; disability; dosage; experimental study; genetic element; illness length; immunogenic; immunogenicity; in vivo evaluation; infection risk; innovation; low and middle-income countries; manufacture; manufacturing scale-up; mortality; new technology; novel; parenteral administration; phase 1 study; pre-clinical; prevent; prophylactic; protective efficacy; protein purification; resistant Shigella; screening; serological marker; success; tissue culture; tool; vaccine candidate

ABSTRACT Shigella spp. are a major global cause of diarrhea and dysentery. Children 2-5 years of age in low- and middle- income countries are the most affected. Mortality is second only to rotavirus among diarrheal diseases in young children, and repeated bouts of disease cause lifelong disability. In industrialized nations, Shigella outbreaks have occurred in day care centers and medical institutions. Shigella spp. rapidly acquire genetic elements that confer antimicrobial resistance. A safe, effective, and affordable vaccine could make a major public health impact, yet none is currently approved. Candidates based on the Shigella-O-antigen are in clinical development. However, that approach is impractical and costly, requiring multiple vaccines to prevent disease caused by Shigella strains with different O antigens. This proposal seeks to develop a safe, practical, and effective broad- spectrum Shigella vaccine based on highly conserved Shigella Type III secretion system (TTSS) proteins, invasion plasmid antigen (Ipa) B, IpaH, and the virulence antigen VirG (IcsA). Our laboratory was the first to report the high immunogenic and broad protective capacity of Shigella IpaB in mice, and the association of IpaB- and VirG- serum IgG (IgG1) levels with clinical protection against shigellosis in humans. Preliminary data in this application demonstrate that VirG also elicits potent and protective immunity. In addition, we have found that adults living in endemic regions who acquire natural immunity to Shigella have high levels of IpaB-, VirG-, and IpaH- serum antibodies. Maternal IgG against these proteins are more efficiently transferred to infants through the placenta as compared to IgG against the O-polysaccharide. High levels of antibodies are also present in breast milk. This robust maternally-derived immunity is consistent with the low incidence of infection at <6 months of life. Together, our findings provide a strong premise for the success of a broad-spectrum subunit (IpaB, IpaH, and/or VirG) Shigella vaccine. Given parenterally, this vaccine is expected to be well-tolerated and to elicit robust immunity in young children, the main target group. In Aim 1, we will purify and characterize Shigella IpaB, IpaH, and VirG using an innovative cell-free protein synthesis system. This technological breakthrough allows the production of high-quality vaccine antigens at large yield and can be easily scaled-up for manufacturing. In Aim 2, we will evaluate the capacity of IpaB, IpaH, and VirG to elicit protective immunity and to confer broad-spectrum protection in mice and guinea pigs. The proteins will be administered parenterally, alone or combined, with alum as adjuvant ‒ a strategy that can be readily translated to humans. In Aim 3, we will investigate the protective role of IpaB, IpaH, and VirG antibodies through passive transfer experiments in mouse and guinea pig infection models and specific steps of infection targeted by each antibody using in vitro cell culture. We have unique expertise, tools, and novel technology to produce a simple and efficacious new subunit vaccine to prevent multidrug-resistant Shigella. If successful, this concept could be easily tested in Phase I studies in humans.

抽象的 Shigella spp。是全球腹泻和痢疾的主要原因。低和中间的2-5岁儿童 收入国家受影响最大。死亡率仅次于年轻的腹泻疾病中的轮状病毒 儿童和反复的疾病会导致终身残疾。工业化国家，志贺氏菌爆发 发生在日托中心和医疗机构中。 Shigella spp。快速获取遗传因素 会议抗菌抗性。安全，有效且负担得起的疫苗可以成为主要的公共卫生 影响，但目前没有批准。基于Shigella-O-Antigen的候选者正在临床发展中。 但是，这种方法是不切实际且昂贵的，需要多种疫苗来预防由 带有不同O抗原的志贺氏菌菌株。该建议旨在开发安全，实用和有效的广泛性 基于高度组成的Shigella III型分泌系统（TTSS）蛋白的光谱志贺氏菌疫苗， 浸润质粒抗原（IPA）B，IPAH和毒力抗原ViRG（ICSA）。我们的实验室是第一个 报告小鼠志贺氏菌IPAB的高免疫原性和广泛保护能力，以及ipab的关联 和Virg-血清IgG（IgG1）水平，具有针对人类志氏症的临床保护。初步数据 应用表明，VIRG还引起了潜在的潜力和受保护的免疫力。此外，我们发现 居住在内在地区的成年人对志贺氏菌的自然免疫具有高水平的IPAB-，VIRG-和 IPAH-血清抗体。针对这些蛋白质的母体IgG通过 与O-polysaccharide相比，lopeta与IgG相比。高水平的抗体也存在 母乳。这种强大的母体衍生的免疫学与小<6个月的低入射率一致 生活。总之，我们的发现为广谱亚基的成功提供了坚实的前提（ipab，ipah， 和/或VIRG）志贺氏菌疫苗。在养生的情况下，这种疫苗有望得到良好的耐受性并引起强大的 幼儿的免疫力，主要目标群体。 在AIM 1中，我们将使用无创新的细胞蛋白来纯化和表征Shigella iPab，IPAH和VIRG 合成系统。这种技术突破允许在整个中生产高质量的疫苗抗原 产量，可以轻松扩大制造业。在AIM 2中，我们将评估IPAB，IPAH和 VIRG引起受保护的免疫力，并在小鼠和豚鼠中召集广谱保护。蛋白质 将以育儿，单独或合并为校友，并以明矾为调整 - 可以轻松地进行调整 - 这种策略 翻译成人类。在AIM 3中，我们将通过IPAB，IPAH和VIRG抗体的保护作用 小鼠和豚鼠感染模型中的被动转移实验以及针对感染的特定步骤 通过使用体外细胞培养的每种抗体。我们拥有独特的专业知识，工具和新颖的技术来生产 简单有效的新亚基疫苗，以防止多药耐药志贺氏菌。如果成功，这个概念 可以在人类的第一阶段研究中很容易测试。