B CELL & T CELL RECOGNITION SITES OF P FALCIPARUM GP195

恶性疟原虫裂殖子表面主要抗原(Gp195)和 其类似物在其他几种疟原虫中诱导保护性 在猿猴和小鼠宿主中的免疫反应，是主要的候选 用于血液期疟疾疫苗。酵母重组gp195 多肽正在被开发为疫苗抗原。药效 这类疫苗的优劣取决于它们诱导 合适的抗原特异性B细胞并有效地刺激 在抗体中充当辅助/诱导细胞的T细胞 免疫应答或非抗体依赖的免疫应答。具体的 该项目的目标是(1)确定B细胞识别位点 参与gp195和gp195相关的抗体反应 多肽和确定H-2连锁的免疫反应 (IR)基因控制对这些识别位点的反应，(2) 为了确定T细胞识别位点，研究IR对它们的调节 基因，并确定T细胞表面表型。 Gp195和重组gp195相关多肽及其合成 多肽，(3)产生gp195特异性T细胞系和 描述其良好的特异性和功能(T助手 活性、产生伽马干扰素)，以及(4)与B细胞相关 和T细胞识别位点到可变的、保守的或群的- Gp195分子的特定区域。B细胞识别位点将 通过用寄生虫纯化的gp195免疫小鼠来定义 和gp195相关多肽与血清抗体检测 用酶联免疫吸附试验检测其特异性。T细胞识别位点将是 使用抗原诱导的增殖试验或 抗原特异性T辅助细胞检测。用于以下目的的抗原 特异性分析为(1)纯化的同源寄生虫 Gp195：(2)异源寄生虫纯化的gp195 对同源蛋白中的特定区域进行分组；(3)重组 不同片段对应的gp195相关多肽 完整的gp195蛋白；(4)合成肽 对应于可变重复区域和潜在的免疫- 通过适当的方法预测优势B细胞或T细胞表位 计算机算法。IR基因对人类免疫缺陷的可能影响 对B细胞和T细胞识别位点的反应性将是 通过比较B细胞和T细胞识别位点进行研究 仅在H-2连接的ir基因上不同的小鼠使用。这个 T细胞和B细胞识别位点的特征为 可变的、保守的或特定于组的尤其与 疫苗的设计将通过比较抗原来完成 同源gp195与异源gp195的特异性 蛋白。

The major merozoite surface antigen (gp195) of P. falciparum and its analogues in several other Plasmodia induces a protective immune response in simian and murine hosts and is a prime candidate for a blood-stage malaria vaccine. Yeast recombinant gp195-based polypeptides are being developed as vaccine antigens. The efficacy of such vaccines is dependent on their ability to induce the appropriate antigen-specific B cells and to efficiently stimulate T cells which serve as helper/inducer cells in the antibody response or in antibody-independent immune responses. The specific aims of this project are (1) to define B cell recognition sites involved in the antibody responses to gp195 and gp195-related polypeptides and to determine whether H-2-linked immune response (Ir) genes control responsiveness to these recognition sites, (2) to define T cell recognition sites, study their regulation by Ir genes, and determine the surface phenotype of T cells induced by gp195 and recombinant gp195-related polypeptides and synthetic peptides, (3) to generate gp195-specific T cell lines and characterize their fine specificity and function (T helper activity, production of gamma interferon), and (4) to relate B cell and T cell recognition sites to variable, conserved, or group- specific regions of gp195 molecules. B cell recognition sites will be defined by immunization of mice with parasite-purified gp195 and gp195-related polypeptides and evaluation of serum antibody specificity by an ELISA assay. T cell recognition sites will be similarly defined using the antigen-induced proliferation assay or antigen-specific T helper cell assays. Antigens to be used for specificity analyses are (1) the homologous parasite-purified gp195: (2) a heterologous parasite-purified gp195 differing in group specific regions from the homologous protein; (3) recombinant gp195-related polypeptides corresponding to different fragments of the complete gp195 protein; and (4) synthetic peptides corresponding to variable repeat regions and to potential immuno- dominant B cell or T cell epitopes predicted by appropriate computer algorithms. The possible influence of Ir genes on responsiveness to B cell and T cell recognition sites will be studied by comparing the B cell and T cell recognition sites utilized by mice differing only at H-2 linked Ir genes. The characterization of T cell and B cell recognition sites as variable, conserved or group-specific is particularly relevant to vaccine design and will be accomplished by comparing antigen specificity for the homologous versus the heterologous gp195 protein.