Development of a prototype Klebsiella O polysaccharide conjugate vaccine

克雷伯菌 O 多糖结合疫苗原型的开发

• 批准号: 8841098
• 负责人: Alan S. Cross
• 金额: $ 23.03万
• 依托单位: UNIVERSITY OF MARYLAND BALTIMORE
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-06-15 至 2017-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8841098
• 关键词: Accounting; Am 80; Anabolism; Animals; Antibiotic Resistance; Antibiotics; Antibodies; Antibody Response; Antigens; Attenuated; Bacteremia; Bacteria; Bacterial Polysaccharides; Carbapenems; Carrier Proteins; Centers for Disease Control and Prevention (U.S.); Cephalosporins; Cessation of life; Chemicals; Chemistry; Clinical; Clinical Research; Conjugate Vaccines; Coupled; Coupling; Data Reporting; Development; Enterobacteriaceae; Francisella; Generations; Genes; Guanosine; Hospitalization; Human; Immune response; Immunocompromised Host; Infection; Intravenous Immunoglobulins; Klebsiella; Klebsiella pneumonia bacterium; Lead; Link; Lipopolysaccharides; Measures; Mediating; Membrane Proteins; Meningitis; Modeling; Monobactams; Multi-Drug Resistance; Mus; Mutation; Nightmare; Nosocomial Infections; Pathway interactions; Peritonitis; Phagocytes; Phase; Pneumonia; Polysaccharides; Predisposition; Preparation; Prevention; Prevention approach; Process; Production; Proteins; Reagent; Recombinants; Resistance; Resort; Salmonella; Series; Seroepidemiologic Studies; Serotyping; Serum; Shigella; Structure; Surface; Surface Antigens; Testing; Time; United States National Institutes of Health; Urinary tract infection; Vaccines; Virulence; Virulent; antimicrobial drug; base; beta-Lactam Resistance; beta-Lactamase; capsule; carbapenem resistance; carbapenemase; cost; cross reacting material 197; enzyme pathway; immunogenic; immunogenicity; in vitro Assay; interest; intraperitoneal; major outer membrane protein; mortality; mouse model; novel; pathogen; protective efficacy; prototype; public health relevance; resistance mechanism; resistant strain; scale up; vaccine candidate; wound

 DESCRIPTION (provided by applicant): Klebsiella pneumoniae (KP) are increasingly important Gram-negative bacterial pathogens that cause pneumonia, wound and urinary tract infections, bacteremia and meningitis. Like other Enterobacteriaceae, KP have become resistant to extended spectrum of beta lactamases (ESBL) antibiotics, including third generation cephalosporins. KP now comprise an increasing percentage of these ESBL-producing bacteria and alarmingly, in the last decade KP have become increasingly resistant to carbapenem. Carbapenamse-resistant KP (KPC) now represent 8% of all KP and in data reported to the CDC have increased over 6 fold in the last decade, resulting in extended hospitalization, increased costs and mortality. These nightmare bugs necessitate the use of toxic, less effective last resort antibiotics. Based on the dwindling pipeline of antibiotics being developed, there is little likelihood that new antibiotics will be available in the near term. A vaccine against KP could elict antibodies that would provide adjunctive therapy for KP that would not be subject to antibiotic resistance mechanisms. We previously developed a 23-valent KP capsular polysaccharide vaccine that progressed to human trials. Since relatively few KP O serotypes account for >70% of KP infections, we reason that a multivalent COPS-based KP vaccine could provide wide coverage and be less difficult and expensive to produce. We propose to develop a prototype conjugate vaccine against the core/O polysaccharide from the lipopolysaccharide (LPS) of a virulent KP (O1K2) linked to an established carrier protein, CRM197 by two different conjugation chemistries. In Specific Aim 1 we will construct a recombinant attenuated strain of KP that can serve as a reagent strain that can be used to safely purify large amounts of KP COPS. As we have successfully done for other GNB pathogens (Shigella, Salmonella, Francisella) we will generate mutations in the guanosine biosynthesis pathway enzymes, and confirm loss of virulence in murine challenge studies. We will generate a second mutation in the genes encoding the KP capsule which will permit a more efficient purification of the surface COPS antigen. In Specific Aim 2 we will test the hypothesis that conjugation of KP type O1 COPS to an established protein carrier, CRM197 will induce anti-LPS antibodies that mediate opsonophagocytosis of KP by phagocytes and will protect mice from lethal homologous KP challenges in both intraperitoneal and intratracheal mouse challenge models. We will vary the linkage (random coupling versus end-linkage) and use of linkers to assess which construct elicits optimal antibody responses and protection. At the conclusion of these studies, we intend to have a KP COPS conjugate vaccine that may serve as a prototype for a multivalent KP COPS vaccine that can be used in the prevention and/or development of a KP-antibody-enriched IVIG for the treatment of KP infection, even if the strains are highly resistant to antibiotics. We also will have a production strain of KP that will be safe for scale-up and allow for more efficient purification of the KP COPS.

 描述（由适用提供）：肺炎克雷伯氏菌（KP）是越来越重要的革兰氏阴性细菌病原体，引起肺炎，伤口和尿路感染，细菌和脑膜炎。像其他肠杆菌科一样，KP也对扩展的β乳糖酶（ESBL）抗生素（包括第三代头孢菌素）具有抵抗力。现在，KP包括这些产生ESBL的细菌中越来越多的百分比，令人震惊的是，在过去的十年中，KP越来越耐碳青霉烯。现在，耐碳酸碳纤维的KP（KPC）占所有KP的8％，在向CDC报告的数据中，在过去十年中，已有6倍以上，导致住院时间扩大，成本和死亡率增加。这些噩梦虫有必要使用有毒，效率较低的最后一种抗生素。基于开发抗生素的流量减少，很少有可能在短期内提供新的抗生素。针对KP的疫苗可能会引起可以为KP提供辅助疗法的抗体，而KP不会受到抗生素耐药机制的影响。我们以前开发了23个价值的KP囊囊多糖疫苗，该疫苗发展为人类试验。由于相对较少的KP O血清型占KP感染的70％，因此我们认为基于多价COPS的KP疫苗可以提供广泛的覆盖范围，并且产生的难度和昂贵。我们建议从两种不同的共轭化学分子中与已建立的载体蛋白（O1K2）的脂多糖（LPS）开发一种原型偶联疫苗，该原型与已建立的载体蛋白（CRM197）相关的脂多糖（LPS）（LPS）。在特定的目标1中，我们将构建一个重组的KP菌株，该菌株可以用作试剂菌株，可用于安全纯化大量的KP COP。正如我们成功为其他GNB病原体（Shigella，Salmonella，Francisella）所做的那样，我们将在鸟嘌呤生物合成途径酶中产生突变，并在鼠挑战研究中确认病毒丧失。我们将在编码KP胶囊的基因中产生第二个突变，这将允许对表面COPS抗原的更有效纯化。在特定目标2中，我们将检验以下假设：KP型O1 COPS结合到已建立的蛋白载体中，CRM197将诱导吞噬细胞介导KP的Opsonophagocyocyposis的抗LPS抗体，并将通过肠内术和肠内质量挑战的同源性KP挑战。我们将改变链接（随机耦合与终端链接），并使用链接器来评估哪种构造引起最佳抗体响应和保护。在这些研究结束时，我们打算采用KP COPS共轭疫苗，该疫苗可以作为多价KP COPS疫苗的原型，该疫苗可用于预防和/或开发KP抗体 - 富集的IVIG KP感染的治疗，即使菌株具有高度抵抗抗生素，也可以用于KP感染。我们还将具有KP的生产菌株，可以安全地扩大规模，并可以更有效地纯化KP COP。