S. typhimiurium Vaccine Against Bacterial Enteropathogens

在每年因传染病死亡的1890万人（1997年）中，约有200万人是由于感染沙门氏菌和其他相关的细菌肠病原体，包括大肠杆菌和志贺氏菌，以及不太密切相关的肠病原体，如霍乱弧菌、空肠弯曲杆菌和单核细胞增多李斯特菌。此外，这些细菌是导致腹泻和全身性疾病的重要原因，这些疾病可以通过污染食品和/或供水传播给人类，这种污染可能是故意的。相信改善健康、营养和经济福利（后者取决于前两者）是提高全球生活质量的最佳手段，从而减少导致战争和恐怖行为的条件，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非重组和重组减毒沙门氏菌兽医疫苗方面的技术进展，以预防和减少由细菌性肠病原体引起的腹泻疾病。我们的目标包括：(i)进一步对一种鼠伤寒沙门氏菌菌株进行基因修饰，该菌株的设计目的是尽量减少对血清型特异性抗原的免疫反应，并最大限度地诱导对不同血清型肠炎沙门氏菌菌株的共同相关抗原的交叉保护免疫，然后对这种修饰菌株作为疫苗进行充分评估，以减少由肠炎沙门氏菌血清型和可能由其他肠道细菌病原体引起的人类腹泻疾病；尤其是EPEC、ETEC和EHEC型大肠杆菌和志贺氏菌；（ii）设计、构建和充分评价与为相同目的而设计的鼠伤寒沙门氏菌疫苗具有相似遗传属性的副伤寒沙门氏菌A的减毒衍生物，以诱导人类产生交叉保护性免疫，以预防肠热，并显著减少因多种肠道沙门氏菌血清型和可能的其他肠道细菌病原体，特别是EPEC、ETEC和EHEC型大肠杆菌和志贺氏菌感染而引起的腹泻疾病；（iii）进一步对旨在诱导交叉保护性免疫的鼠伤寒沙门氏菌和甲型副伤寒沙门氏菌疫苗进行遗传修饰，使其也显示出生物遏制作用，从而使其在肠道或自然界中存活的能力降低，并/或在交付给免疫个体后经过大约10次细胞分裂后裂解死亡；（iv）设计、构建和评估重组减毒沙门氏菌疫苗，利用免疫原性、生物遏制和抗原递送的最佳属性，表达抗原，进一步增强对沙门氏菌相关细菌性肠病原体的交叉保护性免疫诱导，或赋予对沙门氏菌相关较少的肠病原体的保护性免疫。

Of the 18.9 million annual deaths (1997) due to infectious diseases, about 2 million are the result of infections by Salmonella and other related bacterial enteropathogens including Escherichia coli and Shigella species, and less closely related enteropathogens such as Vibrio cholerae, Campylobacter jejuni and Listeria monocytogenes. In addition, these bacteria are responsible are responsible for significant morbidity causing diarrheal and systemic diseases that can be transmitted to humans by contamination of food products and/or the water supply and such contamination can be willful. 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 and thus reduce conditions that result in warlike and terrorist behavior, we propose a vaccine developmental program based on our recent technical developments in using non-recombinant and recombinant attenuated Salmonella veterinary vaccines to prevent-reduce diarrheal diseases caused by bacterial enteropathogens. Our objectives include: (i) to further genetically modify a strain of Salmonella typhimurium that has been designed to minimize induction of immune responses to serotype-specific antigens and to maximize induction of cross protective immunity to common related antigens of S. enterica strains of diverse serotype and then fully evaluate this modified strain as a vaccine to reduce diarrheal diseases in humans caused by S. enterica serotypes and possibly by other bacterial enteric pathogens, especially Escherichia coli of the EPEC, ETEC and EHEC types and Shigella; (ii) to design, construct and fully evaluate an attenuated derivative of S. paratyphi A, with similar genetic attributes as the S. typhimurium vaccine designed for the same purpose, to induce cross protective immunity in humans to prevent enteric fever and to significantly reduce diarrheal diseases due to infection by diverse S. enterica serotypes and possibly by other bacterial enteric pathogens, especially E. coli of the EPEC, ETEC and EHEC types and Shigella; (iii) to further genetically modify the S. typhimurium and S. paratyphi A vaccines designed to induce cross protective immunity to also display biological containment so that they are less able to survive in the intestinal tract or in nature and/or die by lysis after approximately ten cell divisions following delivery to the immunized individual; and (iv) to design, construct and evaluate recombinant attenuated Salmonella vaccines, using optimal attributes for immunogenicity, biological containment and antigen delivery, to express antigens to further enhance induction of cross protective immunity to Salmonella-related bacterial enteropathogens or to confer protective immunity to one of the less Salmonella-related enteropathogens. We will also collaboratively work to develop our Master File, 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 by clinically evaluated in human volunteers.