PEPTIDES/MHC I COMPLEXES AND CD8+ T CELLS

在这项正在进行的对小鼠CD8 T淋巴细胞的研究中，我们的重点将从体外研究它们，作为长期培养的克隆，转移到在它们的自然栖息地老鼠身上研究它们。在过渡过程中，我们将专注于开发免疫原和免疫策略，以刺激原始CD8细胞成为效应细胞，主要是细胞毒性T淋巴细胞(CTL)。为了开发这种有可能在大量人群中应用的“CD8疫苗”，我们的重点将放在含有蛋白质或大蛋白质片段的免疫原上，这些蛋白质或大蛋白质片段可以最终进入抗原提呈细胞的正确抗原处理途径。DNA疫苗目前在这方面很有希望。Heath休克融合蛋白最近已成为可能的替代候选蛋白。主要目标将是开展DNA疫苗和热休克融合蛋白的比较研究，这两种蛋白都具有(或编码)相同的多肽前体，即一种有效的八肽激动剂，用于研究充分研究的CD8T细胞克隆(2C)的抗原特异性受体。从表达这种受体的转基因小鼠(2C TCR)开始，我们将分析它们的2个TCR+细胞对这些免疫原在不同小鼠中的反应，包括来自转基因捐赠者的过继转移细胞。其他研究将集中在：1)阐明热休克融合蛋白异常免疫原性的基础；2)建立肿瘤模型，跟踪CD8 T细胞在小鼠体内的移动和分布，其TCR识别肿瘤细胞上的多肽-MHC复合体；以及III)比较TCR与活2C细胞的亲和力，其中一些细胞有CD8联合受体分子，有些没有CD8联合受体分子。

In this ongoing study of murine CD8 T lymphocytes our emphasis will shift from studying them ex vivo, as clones in long-term culture, to studying them in mice, their natural habitat. In making the transition, we will focus on developing immunogens and immunization strategies that stimulate naive CD8 cells to become effector cells, primarily cytotoxic T lymphocytes (CTL). To develop such "CD8 vaccines", having the possibilities for application in large human populations, our emphasis will be on immunogens that contain proteins or large protein fragments that can end up in the proper antigen-processing pathway of antigen- presenting cells. DNA vaccines are currently promising for this purpose. Heath shock fusion proteins have recently emerged as possible alternative candidates. A major aim will be to carry out comparative studies of DNA vaccines and heat shock fusion proteins, both having (or encoding) the same polypeptide precursor of a potent octapeptide agonist for the antigen-specific receptor of a well studied CD8 T cell clone (2C). Starting with transgenic mice expressing this receptor (2C TCR), we will analyze the response of their 2 TCR+ cells to these immunogens in various mice, including adoptive transfer recipients of the cells from transgenic donors. Other studies will concentrate on i) elucidating the basis for the unusual immunogenic properties of heat shock fusion proteins, ii) developing a tumor model for tracking the mobility and distribution in mice of CD8 T cells whose TCR recognizes peptide-MHC complexes on the tumor cells, and iii) comparing TCR affinity on live 2C cells, some having and some not having CD8 co-receptor molecules.