Towards a New Generation of Glycoengineered Pneumococcal Bioconjugate Vaccines

迈向新一代糖工程肺炎球菌生物结合疫苗

• 批准号: 9341709
• 负责人: Mario Feldman
• 金额: $ 21.01万
• 依托单位: VAXNEWMO, LLC
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-02-22 至 2019-02-21
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9341709
• 关键词: 5 year old; Adult; Age-Years; Amino Acids; Bacteremia; Bacterial Pneumonia; Biological Products; Carrier Proteins; Chemicals; Child; Chronic; Clinical; Communities; Complex; Conjugate Vaccines; Development; Enzymes; Epitopes; Escherichia coli; Exotoxins; Funding; Generations; Glucose; Glycoconjugates; Heterogeneity; Immune response; Immunoglobulin G; Immunologic Memory; Immunosuppression; Infant; Klebsiella; Legal patent; Link; Longevity; Meningitis; Methods; Organism; Otitis Media; Pathogenicity; Patients; Phase; Phase I Clinical Trials; Pneumococcal Infections; Pneumococcal Pneumonia; Pneumococcal conjugate vaccine; Pneumococcal vaccine; Pneumonia; Polysaccharides; Preventive therapy; Prevnar; Procedures; Production; Protein Biosynthesis; Proteins; Recombinants; Research; Safety; Scheme; Serotyping; Shigella dysenteriae; Site; Source; Streptococcus pneumoniae; Synthesis Chemistry; Technology; Time; Translations; Vaccines; World Health Organization; base; capsule; chemical reaction; cost; cross reacting material 197; glycosylation; immunogenic; immunogenicity; innovation; innovative technologies; killings; next generation; novel; pathogen; pathogenic Escherichia coli; preclinical study; success; sugar; tetanus toxin fragment C; vaccine development

PROJECT SUMMARY Pneumococcal pneumonia remains the leading cause of bacterial pneumonia in both children under 5 years of age and adults over 65 years of age. The standard, preventative therapy is the conjugate vaccine, Prevnar-13, which consists of an immunogenic carrier protein covalently attached to one of thirteen pneumococcal capsular polysaccharides. Although Prevnar-13 has significantly reduced the burden of pneumococcal disease, it only protects against 13 of the 90 plus pneumococcal serotypes; furthermore, current methods employed to expand the serotype coverage are notoriously slow requiring complex synthetic chemistries to link a new pneumococcal capsular polysaccharide to the immunogenic carrier protein. Over the last decade, we have been pioneering an innovative approach to conjugate vaccine development that drastically simplifies the production of glycoconjugates. This glycoengineering strategy, consisting of the exploitation of bacterial glycosylation machineries to generate “bioconjugates”, eliminates the need of intricate chemical conjugation methods by employing conjugating enzymes to attach polysaccharides to acceptor proteins in Escherichia coli. Two conjugating enzymes, PglB and PglL, have been commercially utilized to generate bioconjugates as they are able to transfer a wide variety of polysaccharides to proteins; however, neither are able to transfer polysaccharides containing glucose at the reducing end (the first sugar of a growing polysaccharide chain). This seemingly simple observation has enormous implications as approximately 80% of pneumococcal capsules contain glucose at the reducing end. Recently, we have identified and patented the first conjugating enzyme that is able to efficiently transfer pneumococcal capsular polysaccharides containing glucose at the reducing end to an acceptor protein. Based on this observation, we will couple our novel conjugating enzyme technology with carrier proteins previously utilized in conjugate vaccine formulations, streamlining the generation of a superior pneumococcal vaccine with broader serotype coverage. Importantly, our glycoengineering strategy does not require pathogenic organisms as a source of polysaccharide nor chemical reactions to link polysaccharides to proteins. The proposed research in this phase I application will focus on (Aim 1) glycoengineering three commercial carrier proteins (exotoxin A, tetanus toxin fragment C, and CRM197) to contain a modular glycotag with pneumococcal capsular polysaccharides generating a new bioconjugate vaccine for pneumococcal serotypes 8, 9V, 14, and 15b. Subsequently (Aim 2) we will demonstrate the immunogenicity and efficacy of our pneumococcal specific bioconjugate vaccine compared to the standard preventative therapy Prevnar-13. Our next step for phase II funding is to expand the serotype coverage included in our bioconjugate vaccine, develop a large-scale purification scheme for obtaining our bioconjugate vaccine, as well as pre-clinical studies to further demonstrate the safety, potency, and efficacy of our next generation glycoengineered pneumococcal bioconjugate vaccine.

项目摘要 肺炎球菌肺炎仍然是5岁以下的两名儿童的主要原因肺炎 年龄和成年人超过65岁。标准的预防疗法是共轭疫苗，PrevNar-13， 由一种共同附着于13个肺炎球菌囊的免疫原性载体蛋白质组成 多糖。尽管Prevnar-13显着降低了肺炎球菌疾病的燃烧，但仅 预防90加肺炎球菌血清型中的13个；此外，用于扩展的当前方法 众所周知，血清型覆盖范围很慢，需要复杂的合成化学物质才能连接新的 免疫原性载体蛋白的肺炎球菌囊囊多糖。在过去的十年中，我们有 正在开创一种创新的方法来共轭疫苗开发，从而极大地简化了 糖缀合物的生产。这种糖化策略，包括细菌的剥削 糖基化机产生“生物缀合物”，消除了复杂的化学共轭的需求 通过采用共轭酶将多糖连接到大肠杆菌中受体蛋白上的方法。 两种共轭酶，PGLB和PGLL已商业用来生成生物缀合物 能够将多种多糖转移到蛋白质上；但是，都不能转移 多糖在还原端（生长多糖链的第一糖）处含有葡萄糖。 这似乎是简单的观察具有巨大的影响，因为大约80％的肺炎 胶囊在还原端含有葡萄糖。最近，我们已经确定并获得了第一个共轭专利 能够有效地转移含有葡萄糖的肺炎球菌多糖的酶 减少受体蛋白的末端。基于此观察，我们将融合我们的新型共轭酶 具有以前在共轭疫苗配方中使用的载体蛋白的技术，简化了 产生具有更宽的血清型覆盖率的上肺炎球菌疫苗。重要的是，我们的 糖化策略不需要致病生物作为多糖或化学的来源 将多糖与蛋白质联系起来的反应。 在此I阶段应用中提出的研究将重点放在（AIM 1）糖原上 商业载体蛋白（Exotoxin A，Tetanius Toxin碎片C和CRM197）包含模块化糖蛋白 与肺炎球菌囊多糖生成新的生物缀合物疫苗的肺炎 血清型8、9V，14和15B。随后（AIM 2）我们将证明 与标准预防疗法PREVNAR-13相比，我们的肺炎球菌特异性生物缀合物疫苗。 我们第二阶段资金的下一步是扩大我们的生物偶联疫苗中包含的血清型覆盖范围， 开发一个大规模纯化方案，用于获得我们的生物偶联疫苗以及临床前研究 进一步证明我们的下一代胶菌的安全性，效力和效率 生物轭疫苗。