Preclinical evaluation of psoralen inactivation as a platform for developing a killed, whole cell vaccine for Enterotoxigenic E. coli (ETEC)

补骨脂素灭活作为开发产肠毒素大肠杆菌 (ETEC) 灭活全细胞疫苗的平台的临床前评估

基本信息

批准号：
10042258
负责人：
Marlena Moors Westcott
金额：
$ 7.75万
依托单位：
WAKE FOREST UNIVERSITY HEALTH SCIENCES
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-06-01 至 2023-05-31
项目状态：
已结题

项目摘要

Westcott.Project Summary/Abstract Enterotoxigenic E. coli (ETEC), Shigella flexneri and Campylobacter jejuni are the predominant bacterial causes of morbidity and mortality from gastrointestinal (GI) disease in the developing world. Episodes of acute diarrhea caused by these agents have been linked to developmental defects and chronic GI syndromes. Vaccines that are safe for use in young children as well as adult travelers and deployed military are needed to prevent infection and post-infection sequellae caused by these organisms. Formalin inactivation is the current standard for generating killed, whole cell bacterial vaccines. This approach does not require genetic manipulations or extensive knowledge of antigens that induce protective immune responses. However, formalin crosslinks proteins, which has the potential to destroy antigenic epitopes that induce protective immune responses in the context of live bacterial infection. We propose to test the feasibility of an alternative inactivation method to generate safe, whole cell vaccines for enteric bacteria. Psoralen is a photoactivatable drug that reversibly intercalates into nucleic acids. Following irradiation with long wavelength UV light (P+UVA), covalent inter-strand crosslinks form at pyrimidine residues, preventing genome replication. Since P+UVA inactivates bacteria by crosslinking nucleic acids rather than proteins, we hypothesize that protein antigens will be preserved in a native form, generating vaccines with superior immunogenicity. We have successfully inactivated ETEC using P+UVA. With this proposal we will extend the ETEC work by comparing P+UVA to formalin-inactivated ETEC with respect to antigen preservation and immunogenicity using established in vitro assays and murine models. A direct comparative analysis of the 2 inactivation methods is needed to assess the value and feasibility of the P+UVA approach as an agile platform for enteric bacterial vaccines, and more generally for vaccines to prevent antibiotic-resistant bacterial infections that impact patient care in hospital settings. . 1

Westcott。项目摘要/摘要肠毒素大肠杆菌（ETEC），Shigella flexneri和弯曲杆菌空肠是主要细菌发展中国家胃肠道（GI）疾病的发病率和死亡率的原因。急性发作这些药物引起的腹泻与发育缺陷和慢性胃肠道综合症有关。需要安全用于幼儿以及成年旅行者和部署军事的疫苗防止这些生物引起的感染和感染后的后遗症。福尔马林失活是当前的产生杀死的全细菌疫苗的标准。这种方法不需要遗传操纵或广泛的抗原诱导保护性免疫反应的知识。然而，福尔马林交叉链接蛋白有可能破坏诱导保护性的抗原表位在活细菌感染的背景下的免疫反应。我们建议测试替代方案的可行性灭活方法可为肠细菌生成安全的全细胞疫苗。 psoralen是一种可光活化的可逆地插入核酸的药物。用长波长紫外线照射后（P+UVA），在嘧啶残基处形成共价式交联，以防止基因组复制。自从 P+UVA通过交联的核酸而不是蛋白质使细菌失活，我们假设该蛋白抗原将以天然形式保存，从而产生具有优质免疫原性的疫苗。我们有使用P+UVA成功灭活ETEC。通过此建议，我们将通过比较来扩展ETEC的工作 P+UVA使用使用抗原保存和免疫原性的福尔马林灭活ETEC 建立的体外测定和鼠模型。对两种灭活方法的直接比较分析是需要评估P+UVA方法的价值和可行性，作为肠细菌的敏捷平台疫苗，更普遍地用于疫苗，以防止抗生素耐药细菌感染会影响患者在医院环境中护理。。 1