Immunological characterization of rationally-designed vaccines against plague in mice and non-human primate models

合理设计的鼠疫疫苗和非人灵长类动物模型的免疫学特征

• 批准号: 10662480
• 负责人: ASHOK K CHOPRA
• 金额: $ 15.55万
• 依托单位: UNIVERSITY OF TEXAS MED BR GALVESTON
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-02-01 至 2026-07-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10662480
• 关键词: Acyltransferase; African Green Monkey; Animals; Antibiotic Resistance; Antibodies; Antibody Formation; Antibody Response; Antibody titer measurement; Antigens; Attenuated; Attenuated Vaccines; Bacteria; Bacterial Antigens; Binding; Bite; Bubonic Plague; Calcium; Case Fatality Rates; Categories; Cells; Cellular Immunity; Cessation of life; China; Clinical; Clinical Research; Clinical Trials; Congo; Coronavirus; Country; Data; Democratic Republic of the Congo; Disease; Disease Outbreaks; Dose; Engineering; Etiology; Exclusion; Exposure to; FDA approved; Fatality rate; Fleas; Fright; Future; Gene Deletion; Generations; Genes; Genetic Engineering; Goals; Human; IL17 gene; Immune response; Immunity; Immunization; Immunize; Immunoglobulin A; Immunoglobulin G; Immunologics; Infection; Injections; Interferon Type II; Intramuscular; Invaded; Iron Overload; Laboratories; Lauric Acids; Left; Legal patent; Lesion; Licensing; Link; Lipopolysaccharides; Lipoproteins; Macaca; Macaca fascicularis; Madagascar; Military Personnel; Modeling; Mucosal Immunity; Mus; Nature; Nepal; Neutrophil Infiltration; Patient-Focused Outcomes; Patients; Peptide Hydrolases; Plague; Plague Vaccine; Plasminogen Activator; Pneumonic Plague; Quarantine; Rattus; Reporting; Resistance; Rodent; Rodent Model; Role; Serum; Signal Transduction; Site; Subunit Vaccines; Symptoms; T cell response; TLR2 gene; TLR4 gene; Testing; Th1 Cells; Toxicology; Type III Secretion System Pathway; Vaccinated; Vaccine Design; Vaccines; Variant; Virulence; Yersinia pestis; Zoonoses; arm; bioweapon; climate change; co-infection; combat; cytokine; emerging human pathogen; immunogenicity; innovation; mouse model; mutant; nonhuman primate; novel; novel coronavirus; pandemic disease; pathogen; pre-clinical; rational design; resistant strain; respiratory; response; translational approach; vaccine access; vaccine candidate; vaccine efficacy; virulence gene

ABSTRACT The increasing number of bubonic/pneumonic plague cases globally (2010-2018), including the U.S., with a ~18% case fatality rate may reflect climate changes and a rodent carrier range shift. The 2017-18 plague outbreak in Madagascar with ~2400 cases (>75% pneumonic) and ~9% causalities has led WHO (April 2018) to intensify the need for developing new generation subunit and live-attenuated plague vaccines. This need is exemplified by deadly plague cases in China (2019) and Congo (2020 with a 35% fatality rate). Y. pestis’ (Yp) ability to persist in dead hosts to resurge after years of silence, existence of antibiotic-resistant strains that occur naturally or have been intentionally developed, and no FDA-approved plague vaccine, is fearsome. Two- component subunit vaccines composed of capsular antigen F1 and a T3SS component and effector LcrV (low calcium response V antigen), which only generate a humoral immune response, provide variable protection in African green monkeys (AGM) and generate poor T cell responses in humans. Such vaccines will not be effective against Yp strains lacking F1 or possessing LcrV variants. Since the cellular immunity is also critical for protection, we focused first on identifying new virulence genes of Yp and then to delete them in combination to develop novel live-attenuated vaccine (LAV) strains. Two such LAVs were 100% attenuated in inducing bubonic/pneumonic plague in mice/rats and generated long-term humoral and cellular immune responses to provide 100% protection to rodents against developing plague. No clinical symptoms of the disease or histopathological lesions were noted either during immunization or when the vaccinated animals were subsequently exposed to Yp CO92 in a more stringent pneumonic plague model. Therefore, further immunological characterization of these mutants and their testing in higher animals, such as cynomolgus macaques (CM) and AGM, will provide a rationale for future clinical studies. There is a precedent for using a LAV against plague (EV76 strain) in humans. However, this vaccine is reactogenic, represents a spontaneous mutant, and causes disease in patients with over iron load. In Aim 1, we will demonstrate efficacy and immune responses of two vaccine candidates generated from Yp CO92 (biovar Orientalis) against other Yp biovars (Antiqua and Medievalis), the F1-minus mutant of CO92, and Yp CO92 with LcrV variants, in bubonic and pneumonic mouse models. Our data with the mutants indicated a role of IL-17 (a Th17 cytokine), Th1-IFN-γ, and antibodies, in protection. In Aim 2, we will study the mechanistic basis of this protection (one chosen mutant) by using RORt-/- mice, which lack Th17 cells, as well as IFN-γ and IgA k/o mice, to discern their links to neutrophil recruitment and mucosal immunity, to combat Yp infection in bubonic/pneumonic plague models. In Aim 3, CM and AGM will be used with one mutant to demonstrate its short- and long-term efficacy in causing bubonic and/or pneumonic plague as well as reactogenicity. The correlates of protective immunity will then be established. These innovative mechanistic/translational approaches will result in effective new generation plague vaccines.

摘要 包括美国在内的全球（2010-2018年）淋巴腺鼠疫/肺鼠疫病例数量不断增加，与 ~18%的病死率可能反映了气候变化和啮齿动物携带者范围的转移。2017-18年瘟疫 马达加斯加爆发疫情，约有2400例病例（>75%为肺炎）和约9%的死亡病例，导致世卫组织（2018年4月） 加强了对开发新一代亚单位和减毒活鼠疫疫苗的需求。这种需要 中国（2019年）和刚果（2020年，死亡率为35%）的致命鼠疫病例就是例证。Y.鼠疫菌 在死亡宿主中持续存在的能力，在多年的沉默后复活，存在发生的抗药性菌株 无论是天然的还是有意开发的，而且没有FDA批准的鼠疫疫苗，都是可怕的。二-- 由荚膜抗原F1和T3 SS组分和效应子LcrV（低）组成的组分亚单位疫苗 钙应答V抗原），其仅产生体液免疫应答，在 非洲绿色猴（AGM）和人类产生不良的T细胞反应。这种疫苗不会有效 针对缺乏F1或具有LcrV变体的Yp菌株。由于细胞免疫对于 保护，我们首先专注于识别Yp的新毒力基因，然后将它们组合删除， 开发新的减毒活疫苗（LAV）菌株。两个这样的LAV在诱导中100%减毒， 腺鼠疫/肺鼠疫小鼠/大鼠，并产生长期的体液和细胞免疫反应， 为啮齿动物提供100%的保护，防止鼠疫的发展。没有疾病的临床症状或 在免疫期间或当接种疫苗的动物 随后在更严格的肺鼠疫模型中暴露于Yp CO 92。因此进一步 这些突变体的免疫学特征及其在高等动物（例如食蟹猴）中的测试 猕猴（CM）和AGM，将为未来的临床研究提供理论依据。有一个使用 LAV抗鼠疫（EV 76株）。然而，这种疫苗是反应原性的，代表了自发的 突变，并导致铁负荷过多的患者患病。在目标1中，我们将证明有效性和免疫性 Yp CO 92（东方生物变种）产生的两种候选疫苗对其他Yp生物变种的应答 （Antiqua和Medievalis），CO 92的F1-负突变体，和Yp CO 92与LcrV变体，在腺泡和 肺炎小鼠模型。我们对突变体的数据表明IL-17（一种Th 17细胞因子）、Th 1-IFN-γ和IFN-γ的作用。 抗体，保护。在目标2中，我们将研究这种保护的机制基础（一种选择的突变体）， 使用缺乏Th 17细胞的ROR α t-/-小鼠以及IFN-γ和伊加k/o小鼠， 招募和粘膜免疫，以对抗淋巴腺/肺鼠疫模型中的Yp感染。在目标3中，CM 和AGM将与一种突变体一起使用，以证明其在引起淋巴腺和/或 肺鼠疫以及反应原性。保护性免疫的相关性将被建立。 这些创新的机制/翻译方法将导致有效的新一代鼠疫疫苗。