Immunization-induced AMI and CMI against malaria

描述（由申请人提供）：通过疫苗接种控制恶性疟原虫疟疾将需要多种寄生虫抗原有效地组合免疫。在这方面，考虑到在红细胞入侵和血清抗体可及性方面的重要功能，在血期分裂子表面表达的蛋白质作为疫苗靶点具有吸引力。然而，由于对保护性反应了解不足和缺乏可测量的免疫相关因素，merozoite抗原疫苗的人体试验进展受到阻碍。本应用程序的目的是通过接种两种裂殖子表面蛋白，顶膜抗原-1 （AMA-1）和裂殖子表面蛋白-1 （MSP-1）来确定保护性免疫的参数。由于AMA-1或MSP-1单独免疫的最佳配方可能不同，我们的重点将放在对联合抗原免疫有效的配方上。我们有一个简单、可行的系统，使用重组AMA-1和MSP-1的组合来免疫小鼠，使其免受夏波疟原虫疟疾的侵害。良好的B细胞应答和显著的抗体产生是保护所必需的，使用明矾或奎尔A作为佐剂可以实现。然而，单独的预激抗体滴度并不能预测保护效果。此外，对B细胞缺陷小鼠的研究发现，一种不依赖抗体的细胞介导成分可诱导Pc MSP-1的保护作用。我们将检查抗体特异性、浓度、同型和亲和力，以确定预测保护效果的可测量参数。通过大规模的DNA微阵列分析，我们将确定Pc AMA-1 + Pc MSP-1免疫和保护动物的CD4+ T细胞的基因表达谱，并将其与完全易感的小鼠进行比较。体外确定的Pc AMA-1 + Pc MSP-1诱导的保护性T细胞和B细胞反应的相关因素将通过被动免疫研究和选定的免疫敲除小鼠的免疫在体内得到验证。随着AMA-1和MSP-1联合制剂进入临床试验，我们期望获得的信息可以应用于评估猕猴和人类的免疫反应。

DESCRIPTION (provided by applicant): The control of Plasmodium falciparum malaria by vaccination will require immunization with multiple parasite antigens effectively formulated in combination. In this regard, proteins expressed on the surface of blood-stage merozoites are attractive as vaccine targets given their functional importance in the invasion of erythrocytes and accessibility to serum antibodies. However, progress toward human trials of merozoite antigen based vaccines has been hampered by an inadequate understanding of protective responses and a lack of measurable correlates of that immunity. The objective of this application is to define parameters of protective immunity targeted by vaccination with two merozoite surface proteins, apical membrane antigen-1 (AMA-1) and merozoite surface protein-1 (MSP-1). Since optimal formulations for immunizations with AMA-1 or MSP-1 alone may differ, our focus will be on formulations that are effective for combined antigen immunizations. We have a simple, workable system using combinations of recombinant AMA-1 and MSP-1 to immunize mice against Plasmodium chabaudi malaria. A good B cell response and significant antibody production are necessary for protection and can be achieved utilizing Alum or Quil A as adjuvant. However, prechallenge antibody titers alone are not predictive of protective efficacy. Furthermore, studies in B cell deficient mice revealed an antibody independent, cell mediated component to Pc MSP-1 induced protection. We will examine antibody specificity, concentration, isotype and avidity to define measurable parameters that predict protective efficacy. By large-scale DNA microarray analyses, we will determine gene expression profiles of CD4+ T cells from Pc AMA-1 + Pc MSP-1 immunized and protected animals compared to those from mice fully susceptible to P. chabaudi malaria. Correlates of Pc AMA-1 + Pc MSP-1 induced protective T cell and B cell responses defined in vitro will be validated in vivo by passive immunization studies and through the immunization of selected immunological knockout mice. We expect that the information gained can be applied to the evaluation of immune responses in Aotus monkeys and humans as combined formulations of AMA-1 and MSP-1 move into clinical trials.