Immunotherapeutics and vaccines against anthrax, plague and tularemia

描述(由申请人提供)：生物防御研究的重点应包括开发免疫疗法和针对生物战剂的有效疫苗。细胞免疫和体液免疫反应可能在炭疽、鼠疫和兔热病的免疫中发挥作用。Vy2V82 T细胞仅存在于灵长类动物体内，占人类血液中Y5 T细胞总数的60-95%。我们和其他人已经证明，磷酸抗原特异性的Vy2V82 T细胞既可以作为先天免疫细胞，也可以作为获得性免疫细胞，并有助于对急性致命形式的结核病进行适应性免疫。我们的新研究表明，炭疽杆菌确实可以产生磷抗原刺激Vy2V52 T细胞，并在随后感染产生磷抗原的分枝杆菌后为这些细胞的交叉反应记忆类型的反应做准备。重要的是，磷酸抗原HMBPP治疗猴子可以使Vy2V52 T细胞在循环T细胞总数中的比例从1%增加到70%。HMBPP激活的Vy2V82 T细胞很容易迁移到肺中，并对猕猴的肺部分枝杆菌感染提供保护。我们推测，磷抗原HMBPP介导的Vy2V52 T细胞活化可以显著增强对炭疽杆菌、鼠疫杆菌和图拉氏杆菌的先天和获得性免疫反应，并对致命的吸入性炭疽、鼠疫和图拉热症具有保护作用。我们进一步假设，由磷抗原和蛋白质抗原组成的联合疫苗可以针对4种免疫成分：Vy2V52T细胞、CD4T辅助细胞、CDS T杀伤分子和抗体，因此可以更有效地进行免疫和疫苗诱导的保护，以预防炭疽、鼠疫和兔热病。为了便于验证这些假设，我们研究了HMBPP治疗方案的临床和免疫学方面，并开发了构建重组卡介苗和李斯特菌疫苗载体的疫苗平台技术。为了验证我们的假设并最终开发针对炭疽、鼠疫和图拉热症的重组疫苗，我们将：i.评估HMBPP方案对非人类灵长类动物致命的吸入性炭疽、鼠疫和图拉热症的免疫治疗效果。表达炭疽杆菌、鼠疫F1或图拉氏杆菌抗原的重组卡介苗和重组减毒李斯特菌疫苗载体的构建及鉴定用表达炭疽杆菌、鼠疫耶尔森氏菌F1或图拉氏杆菌抗原的重组卡介苗和李斯特氏菌疫苗载体，比较口服和皮内免疫方式对接受异种加强免疫的猴子的疫苗诱导的免疫反应。IV.确定表达PA、F1或图拉热抗原的重组卡介苗和李斯特氏菌疫苗载体口服加强免疫是否能对非人类灵长类动物的致命吸入性炭疽、鼠疫和图拉热症产生保护性免疫。

DESCRIPTION (provided by applicant): Biodefense research priorities should include development of immunotherapeutics and effective vaccines against biological warfare agents. Both cellular and humoral immune responses may play a role in immunity to anthrax, plague and tularemia. Vy2V82 T cells exist only in primates and constitute 60-95% of total human y5 T cell population in the blood. We and others have demonstrated that phosphoantigen-specific Vy2V82 T cells can function as both innate and adaptive immune cells, and contribute to adaptive immunity to acutely fatal form of tuberculosis. Our new studies indicate that B. anthracis can indeed produce phosphoantigen stimulating Vy2V52 T cells and prime these cells for cross-reactive memory-type response after subsequent infection with phosphoantigen-producing mycobacteria. Importantly, phosphoantigen HMBPP treatment of monkeys can expand Vy2V52 T cells from <1% to > 70% in total circulating T cells. HMBPP-activated Vy2V82 T cells readily migrate to the lung and confer protection against pulmonary mycobacterial infection in macaques. We hypothesize that phosphoantigen HMBPP-mediated activation of Vy2V52 T cells can greatly boost innate and adaptive immune responses to B. anthracis, Y. pestis and F. tularensis, and confer protection against fatal inhalational anthrax, plague and tularemia. We further hypothesize that a combined vaccine comprised of both phosphoantigen and protein antigen can target 4 immune components: Vy2V52 T cells, CD4 T helpers, CDS T killers, and antibodies, and therefore can be more efficient for immunization and vaccine-induced protection against anthrax, plague and tularemia. To facilitate testing these hypotheses, we have worked out clinical and immunological aspects of HMBPP treatment regimens, and developed vaccine platform technology for constructing recombinant BCG and Listeria vaccine vectors. To test our hypothesis and ultimately develop recombinant vaccines against anthrax, plague and tularemia, we will: I. Assess HMBPP regimens for immunotherapeutic effects on fatal inhalational anthrax, plague, and tularemia in nonhuman primates. II. Construct and characterize recombinant BCG and recombinant attenuated Listeria vaccine vectors expressing B. anthrax PA, Y. pestis F1 or F. tularensis Ag. III. Compare oral and intradermal immunization routes for vaccine-elicited immune responses in monkeys that receive heterologous prime-boost vaccination with recombinant BCG and Listeria vaccine vectors expressing B. anthracis PA, Y. pestis F1, or F. tularensis Ag. IV. Determine whether oral heterologous prime-boost vaccination with recombinant BCG and Listeria vaccine vectors expressing PA, F1, or tularemia Ag can confer protective immunity against fatal inhalational anthrax, plague and tularemia in nonhuman primates.