Translation Research in Plasmodium vivax

这项建议中描述的研究的目的是识别和表征针对已定义和新发现的间日疟原虫红血球前期和蚊子阶段抗原的保护性免疫反应，然后在Aotus猴子模型中开发诱导这些免疫反应并提供保护的疫苗。(A)将在终生暴露于间日疟原虫的流行区居民以及用辐照间日疟原虫子孢子免疫并被证明能抵抗子孢子攻击的志愿者中确定被认为参与保护的免疫反应。(B)保护性生物活性的测试将在体内通过评估Aotus猴子和人类志愿者的寄生虫血症来进行，在体外通过评估血清抑制子孢子入侵肝细胞、在肝细胞培养中抑制子孢子的发育、在血期培养中抑制子孢子的发育，以及通过评估以含有配子细胞的血期培养物喂养的白纹伊蚊的卵囊发育来进行。(C)来自受保护和非受保护个人的血清将以子孢子、肝脏和血液期IFAT为特征，并通过使用选定的全长重组蛋白、长肽或成分表位的ELISA法进行鉴定。我们首先将重点放在可用的试剂上：PvsP和PvSSP2/TRAP(子孢子和肝期抗原)，PvMSP-1和PvDBP(血液期抗原)和Pvs25/28(在蚊子肠道表达的抗原)。当其他抗原可用时，将对其进行研究。淋巴细胞将以CTL和干扰素伽马为特征，ELISPOT对来自PvCSP和PvSSP2(以及由各种佐剂、DNA质粒和重组痘病毒以及猴子模型形成的蛋白质或多肽)产生的表位做出反应。我们将利用Aotus的血液期挑战模型和新开发的Aotus的子孢子挑战模型。这项研究项目将综合使用过去十年在哥伦比亚西部精心开发的实验室、灵长类设施、杀虫剂和野外场地，以回答关于这种重要但相对被忽视的疟疾寄生虫的这些关键生物学问题。

The purpose of the research described in this proposal is to identify and characterize protective immune responses against defined and newly discovered Plasmodium vivax antigens from the pre-erythrocytic and mosquito stages of the parasite., and then to formulate vaccines that induce these immune responses and provide protection in the Aotus monkey model. (A) Immune responses thought to be involved in protection will be identified in residents of endemic areas with life-long exposure to P. vivax malaria and also in volunteers immunized with irradiated P. vivax sporozoites and shown to be protected against sporozoite challenge. (b) Testing for protective biological activity will be done in vivo by assessing parasitemia in Aotus monkeys and in human volunteers, and in vitro by assessing the ability of sera to inhibit sporozoite invasion of hepatocytes, development of sporozoites in hepatocyte culture, and development of blood stages in blood stage culture, and by assessing oocyst development in Anopheles albimanus fed on blood stage cultures containing gametocytes. (c) Sera from protected and non protected individuals will be characterized by sporozoite, liver and blood stage IFAT and by ELISA utilizing selected full length recombinant proteins, long peptides or components epitopes. We will focus initially on reagents that are available: PvSP and PvSSP2/TRAP (sporozoite and liver stage antigens), PvMSP-1 and PvDBP (blood stage antigens) and Pvs25/28 (antigens expressed in the mosquito gut). Other antigens will be studied as they become available. Lymphocytes will be characterized by CTL and interferon gamma production by ELISPOT in response to epitopes derived from the PvCSP and PvSSP2 (and from proteins or peptides formulated with various adjuvants, DNA plasmids, and recombinant poxviruses, and monkey models. We will utilize the blood stage challenge model in Aotus and a newly developed sporozoite challenge model in Aotus. This research project will integrate the use of laboratories, primate facilities, insectories and field sites painstakingly developed over the last decade in western Columbia in order to answer these critical biological questions about this important but relatively neglected malaria parasite.