STIMULATION OF CELLULAR IMMUNITY WITH ANTHRAX LETHAL TOXIN-ANTIGEN FUSIONS

炭疽杆菌分泌两种毒素到细胞外介质中 在成长过程中。 这两种毒素由三种不同的蛋白质组成， 以成对的方式联合收割机。 保护性抗原（PA）可联合收割机 致死因子（LF）或水肿因子（EF）。 PA结合LF使致命 PA与EF结合产生水肿毒素。 每种毒素的一部分 直接运输到活细胞的胞质溶胶，在那里发挥其 效果（参见Arora，N.，K.R. Klimpel，Y. Singh和S.H. Leppla，1992，J Biol Chem 267：15542-15548）。 我们建议利用高效的 将蛋白质递送到胞质溶胶， 细胞 几乎所有的细胞类型都有能力处理蛋白质， 并将它们与MHC I类分子联合收割机结合。 的 加工蛋白与MHC I类分子的组合 在活细胞表面呈现的刺激导致 识别经加工的蛋白质抗原的T细胞群。 一旦受到刺激，这群T细胞就可以扩增并启动 快速反应并清除携带相同 MHC I类和加工抗原的组合。 通过融合 LF和不同的多肽抗原之间的差异， 一个能抵抗多种病原体的宿主 我们最初的工作将集中在启动一个 针对HIV-1表达的几种已知抗原蛋白的应答， 包括gp 120、gp 41、p24、Nef、达特和Rev.

Bacillus anthracis secretes two toxins into the extracellular medium during growth. The two toxins consist of three distinct proteins which combine in a pairwise fashion. Protective antigen (PA) can combine with lethal factor (LF) or edema factor (EF). PA combined with LF makes lethal toxin while PA combined with EF makes edema toxin. Part of each toxin is directly transported to the cytosol of living cells where it exerts its effect (see Arora, N., K.R. Klimpel, Y. Singh, and S.H. Leppla, 1992, J Biol Chem 267:15542-15548). We propose to take advantage of the efficient delivery of proteins to the cytosol to intracellularly inoculate living cells. Nearly all cell types have the ability to process proteins found in the cytosol and combine them with MHC class I molecules. The combination of the processed protein with the MHC class I molecule presented on the surface of the living cell results in the stimulation of a population of T-cells which recognize the processed protein antigen. Once stimulated, this population of T-cells can expand and become primed to rapidly respond to and eliminate cells which bear an identical combination of MHC class I and processed antigen. By making fusions between LF and different polypeptide antigens we may be able to vaccinate a host against many pathogens. Our initial work will focus on priming a response against several known antigenic proteins expressed by HIV-1, including gp120, gp41 p24, Nef, Tat and Rev.