Recombinant Attenuated Salmonella Vaccines for Humans

在过去十年中，平均每年有5700万人死亡，其中2000多万人直接死于传染病，另有数百万人死于感染的继发性影响。每年因伤寒沙门氏菌、肺炎链球菌和结核分枝杆菌感染而死亡的人数差别很大，但可能占死亡总数的13%左右，由于与这些疾病有关的严重发病率，费用甚至更高。我们认为，改善健康、营养和经济福祉（后者依赖于前两者）是提高全球生活质量的最佳手段，因此我们提出了一项疫苗开发计划，该计划基于我们最近在使用重组减毒沙门氏菌疫苗（RASV）方面的技术发展。我们的具体目的是：（1）评估S。鼠伤寒沙门氏菌RASV最近完善和改进的基因型，以提供五种不同的S。肺炎链球菌保护性蛋白抗原，并比较三种菌株的混合物与递送所有五种抗原的单一菌株的抗原递送，以最大化诱导粘膜和全身性抗体应答，并评估（i）抗体对多种肺炎链球菌的亲和力。pneumoniae菌株代表全球分布的主要血清型，和（ii）诱导保护性免疫的鼻内定植和致命的挑战与小鼠适应的S。pneumoniae菌株，（2）用最佳的S.鼠伤寒沙门氏菌RASV和S.伤寒RASV基本上相同的基因型，以验证S。Typhi RASV用于在未来的人类临床试验中进行评估，然后通过提供菌株和试剂并在必要时协助评估和验证来支持这样的临床试验，（3）完善用于通过T2 SS递送Mtb抗原的改进的RASV调节的延迟裂解系统，在真核细胞胞质溶胶中的T3 SS和裂解以产生CD 4-和CD 8-针对Mtb感染的依赖性免疫，并评价通过单独的RASV-Mtb疫苗免疫和用M.（4）设计、构建和评价重组减毒S.伤寒调节延迟裂解系统产生Mtb抗原的最佳组合（由特异性目标3确定，并通过T2 SS、T3 SS和裂解在真核细胞胞质溶胶中递送，以提供针对Mtb感染的保护。我们将添加到我们的主文件（提交给FDA），准备并充分表征候选疫苗主种子的稳定性和安全性，准备并提交IRB批准的方案，提交获得IND所需的信息，并执行任何其他必要的工作，以安排在未来的研究中对最佳候选疫苗进行临床评价。

DESCRIPTION (provided by applicant): Of the average 57 million annual deaths over the past ten years, more than 20 million are directly due to infectious diseases with millions more due to secondary effects of infections. The numbers of annual deaths due to infections by Salmonella Typhi, Streptococcus pneumoniae and Mycobacterium tuberculosis (Mtb) vary widely but may account for about 13 per cent of the total deaths with an even greater cost due to the severe morbidity associated with these diseases. In the belief that improving health, nutrition and economic well being (the latter dependent on the first two) provide the best means to enhance the quality of life globally, we propose a vaccine development program based on our recent technical developments in using recombinant attenuated Salmonella vaccines (RASV). Our Specific Aims are: (1) to evaluate S. Typhimurium RASVs with recently perfected and improved genotypes to deliver five different S. pneumoniae protective protein antigens and compare antigen delivery by a mixture of three strains versus a single strain delivering all five antigens o maximize induction of mucosal and systemic antibody responses and to evaluate (i) antibody affinity to a diversity of S. pneumoniae strains representing the major serotypes distributed globally and (ii) induction of protective immunity to intranasal colonization and lethal challenge with mouse-adapted S. pneumoniae strains, (2) to conduct all needed preclinical studies with the optimal S. Typhimurium RASV and with the S. Typhi RASV of essentially the same genotype to validate the S. Typhi RASV for evaluation in future human clinical trials and to then support such clinical trials by providing strains and reagents and assisting in evaluations and verifications, as necessary, (3) to perfect the improved RASV regulated delayed lysis system for delivery of Mtb antigens by T2SS, T3SS and lysis in eukaryotic cell cytosol to generate both CD4- and CD8-dependent immunities against Mtb infection and to evaluate protection conferred by immunization by RASV-Mtb vaccines alone and following initial immunization with M. bovis BCG, and (4) to design, construct and evaluate recombinant attenuated S. Typhi regulated delayed lysis systems producing the optimal combination of Mtb antigens (determined from Specific Aim 3 and delivered by T2SS, T3SS and lysis in the eukaryotic cell cytosol to confer protection against Mtb infection. We will add to our Master File (filed with FDA), prepare and fully characterize candidate vaccine Master Seeds for stability and safety, prepare and submit protocols for IRB approvals, submit information necessary to obtain INDs, and perform any other work needed to arrange that the best candidate vaccines be clinically evaluated in future studies.