Targeting T3SA proteins as protective antigens against Yersinia

总结 鼠疫耶尔森氏菌可引起淋巴腺鼠疫、败血症鼠疫和肺鼠疫， 没有立即治疗。虽然Y.鼠疫对许多抗生素敏感， 时至今日，鼠疫已得到控制，但鼠疫仍在Y.鼠疫 在野生啮齿类动物中建立了持久的地方性流行病循环。在2015年，报告了15起鼠疫病例， 在美国，有几种发生在国家公园，病死率约为33%。这突出表明 与这种毁灭性疾病作斗争的挑战。此外，Y.鼠疫已被部署为 它是一种生物武器，由于其遗传上的易处理性、自然获得的抗生素耐药性和相对 从自然中获取的容易性，Y。鼠疫已被列为一种可武器化的病原体， 造成大范围的人类死亡耶尔森菌对人类有致病性的三型病毒 分泌系统（T3 SS），是毒力所必需的。这种T3 SS将蛋白质效应物注入宿主细胞， 为了细菌的利益操纵功能。T3 SS装置（T3 SA）提供通电的 用于将这些效应物从细菌移位到宿主细胞质中的管道。外部 T3 SA的部分是针、尖端蛋白和两个转运蛋白中的第一个。对于耶尔森氏菌， LcrV是针尖蛋白，YopB是第一个转运蛋白。这些蛋白质高度保守 在耶尔森氏菌属（Yersinia spp.）并且是发病所必需的。我们已经证明，当管理 鼻内（IN）在适当的佐剂存在下，这两种蛋白质保护小鼠免受致命的免疫损伤。 挑战Y鼠疫菌和Y.小肠结肠炎我们已经融合了LcrV和YopB来产生YerF，并融合了 LTA 1是产肠毒素E.大肠杆菌，至N-末端 来产生L-YerF。在这一建议中，我们打算评估L-YerF作为一个自我， 佐剂保护性亚单位疫苗。我们假设L-YerF将提供体液和细胞 免疫反应，将保护小鼠免受感染引起肺鼠疫和淋巴腺鼠疫。

Summary Yersinia pestis causes bubonic, septicemic and pneumonic plague with high rates of mortality in the absence of immediate treatment. Although Y. pestis is susceptible to many antibiotics and outbreaks have been contained in present day, plague continues to cause lethal human infections in areas where Y. pestis has established persistent enzootic cycles in wild rodents. In 2015, 15 plague cases were reported in the United States, several occurring in National Parks, with a case fatality rate of ~33%. This underscores the challenges associated with combatting this devastating disease. Additionally, Y. pestis has been deployed as a biological weapon and with its genetic tractability, natural acquisition of antibiotic resistance and relative ease of acquisition from nature, Y. pestis has been classified as a weaponizable pathogen with the potential for inflicting widespread human death. Yersinia spp. that are pathogenic for humans possess a type III secretion system (T3SS) that is essential for virulence. This T3SS injects protein effectors into host cells to manipulate functions for the benefit of the bacterium. The T3SS apparatus (T3SA) provides the energized conduit for translocation of these effectors from the bacterium and into the host cell cytoplasm. The external portions of the T3SA are the needle, the tip protein and the first of two translocator proteins. For Yersinia, LcrV is the needle tip protein and YopB is the first translocator protein. These proteins are highly conserved among Yersinia spp. and are required for pathogenesis. We have demonstrated that, when administered intranasally (IN) in the presence of the appropriate adjuvant, these two proteins protect mice against a lethal challenge by Y. pestis and Y. enterocolitica. We have fused LcrV and YopB to produce YerF and have fused LTA1, the active moiety of dmLT (double mutant labile toxin) from enterotoxigenic E. coli, to the N-terminus of these fusions to produce L-YerF. Within this proposal, we intend to assess the L-YerF as a self- adjuvanting protective subunit vaccine. We hypothesize that L-YerF will provide humoral and cellular immune responses that will protect mice against infections causing pneumonic and bubonic plague.