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)腺/肺鼠疫病例数量不断增加， ~18%的病死率可能反映了气候变化和鼠类携带范围的转移。2017-18年的鼠疫 马达加斯加爆发了约2400例(75%肺炎)和约9%的死亡病例，导致世卫组织(2018年4月) 加强开发新一代亚单位和减毒活鼠疫疫苗的必要性。这一需求是 例如中国(2019年)和刚果(2020年，死亡率为35%)的致命鼠疫病例。鼠疫耶尔森氏菌(Yp) 能够在死亡的宿主中坚持多年后复活，存在出现抗药性的菌株 自然或故意开发的，没有FDA批准的鼠疫疫苗，是可怕的。两个- 由囊膜抗原F1和T3SS组分和效应器LcrV(Low)组成的组亚基疫苗 钙反应V抗原)，它只产生体液免疫反应，在 非洲绿猴子(AGM)和在人类中产生较差的T细胞反应。这样的疫苗不会有效 对缺乏F1或具有LcrV变异体的YP菌株。因为细胞免疫也对 保护，我们首先专注于鉴定新的yp毒力基因，然后将它们联合删除以 开发新型减毒活疫苗(LAV)毒株。两个这样的LAV在诱导过程中100%减弱 小鼠/大鼠腺/肺鼠疫，并产生长期体液和细胞免疫反应 为鼠类提供100%保护，使其免受正在发展的鼠疫的侵袭。没有疾病的临床症状或 在免疫期间或在接种疫苗的动物 随后在更严格的肺鼠疫模型中暴露于YP CO92。因此，进一步 这些突变体的免疫学特征及其在高等动物(如食蟹)中的检测 猕猴(CM)和AGM，将为未来的临床研究提供理论基础。已经有过使用 人类抗鼠疫病毒(EV76株)。然而，这种疫苗是有反应性的，代表着一种自发的 突变，在铁负荷过高的患者中会导致疾病。在目标1中，我们将展示有效性和免疫力 来自yp CO92(生物群)的两个候选疫苗对其他yp生物群的免疫应答 (安提瓜和麦迪瓦利斯)，CO92的F1-减去突变体，以及带有LcrV变体的YP CO92，在Buumonic和 肺炎小鼠模型。我们对突变体的数据表明IL-17(Th17细胞因子)、Th1-干扰素-γ和 抗体，在保护中。在目标2中，我们将通过以下方式研究这种保护的机制基础(一个选定的突变体) 使用缺乏Th17细胞的RoRt-/-小鼠以及干扰素-γ和IgA k/o小鼠来识别它们与中性粒细胞的联系 招募和粘膜免疫，以对抗腺/肺炎鼠疫模型中的yp感染。在目标3中，CM AGM将与一种突变体一起使用，以证明其在引起腺瘤和/或 肺炎鼠疫以及反应性。然后将建立保护性免疫的相关性。 这些创新的机械/转化方法将产生有效的新一代鼠疫疫苗。