ALLOGENEIC RESPONSE:ROLE OF T CELL RECEPTOR DIVERSITY

T细胞受体的相互作用，一种II类组织相容性 分子和抗原是免疫识别所必需的。 T细胞受体和II类分子的多样性是 参与产生反应的特异性。而当 产生潜在多样性的机制被明确定义， 塑造T细胞受体的力量可用于 与抗原的相互作用还没有完全被理解 人类。尽管多样性的许多方面都会影响到这一点 互动，这项研究将重点放在生殖系的重要性上 特定T细胞受体基因的多样性(谱系) 细胞免疫反应，并将检查以下内容：(1) 曲目对肌动蛋白功能特异性的影响 同种异体反应性T淋巴细胞克隆的测定 HLA型评价组的识别；(2)曲目的效果 上述基因表达的T细胞受体的一级结构 同种异体反应性克隆的基因序列分析； 非MHC、非T细胞受体成分的作用 (遗传/环境)对功能特异性和结构的影响 上述同种异体反应克隆所利用的T细胞受体。这个 T细胞对同种异体人类II类分子的反应将是 用来采样可用的T细胞，作为模型的谱系 抗原识别。控制胸腺选择的影响 MHC对人类白细胞抗原相合同胞T细胞受体表达的影响 将在这项研究中用作响应者。用T-RFLP进行分析 细胞受体V片段探针，反应者携带不同 亲本T细胞受体β链基因的组合。这个 刺激者(应答者的人类白细胞抗原重组兄弟姐妹)分享 一种与应答者的单倍型，仅在班级上不同 第二单倍型的II区。虽然刺激器和 应答者在DR、DQ和DP基因座、启动和选择上存在差异 使用的协议将优先生成可识别 DR分子。为了进一步集中DR特异性T细胞 对少量刺激决定因素的反应，即启动 已经选择了组合，以便响应器和刺激器 表达只有三个氨基酸差异的DR变异体。使用 这种方案中，T细胞的反应可以集中在有限的和 精确定义的分子差异，从而限制了 这种反应的异质性。在功能级别上， 同种异体反应性T细胞克隆的特异性和异质性 使用该引爆组合生成的引爆组合将使用 HLA型试板和单抗阻断研究。在……上面 分子水平，T细胞反应的异质性和 特异性T细胞受体基因的使用将通过cDNAs进行研究 T细胞受体α和β可变区的序列测定 基因。如果有不同利用的细分市场，将 通过与克隆基因的杂交研究和 序列特异性探针和DNA序列分析以检测 基因片段的缺失或改变 响应者。

The interaction of a T cell receptor, a class II histocompatibility molecule and antigen is essential for immune recognition. Diversity of both the T cell receptor and the class II molecule is involved in generating the specificity of the response. While the mechanisms which generate potential diversity are clearly defined, the forces which shape the T cell receptors available for interaction with antigen are not yet completely understood in the human. Although many aspects of diversity impinge on this interaction, this study will focus on the importance of germline diversity (repertoire) of T cell receptor genes in a specific cellular immune response and will examine the following: (1) The effect of the repertoire on the functional specificity of alloreactive T lymphocyte clones as measured by the patterns of recognition of an HLA-typed panel; (2) The effect of the repertoire on the primary structure of T cell receptors expressed by the above alloreactive clones as measured by cDNA sequence analysis; and (3) The effect of nonMHC, nonT cell receptor components (genetic/environmental) on the functional specificity and structure of T cell receptors utilized by the above alloreactive clones. The T cell response to an allogeneic human class II molecule will be used to sample the available T cell, repertoire as a model of an antigen recognition. To control the influence of thymic selection by MHC on the expressed T cell receptors, HLA identical siblings will be used as responders in the study. By RFLP analysis with T cell receptor V segment probes, the responders carry different combinations of parental T cell receptor beta chain genes. The stimulator (an HLA recombinant sibling of the responders) shares one HLA haplotype with the responders and differs only at the class II region of the second HLA haplotype. Although the stimulator and responders differ at DR, DQ and DP loci, the priming and selection protocols used will preferentially generate clones which recognize the DR molecule. In order to further focus the DR-specific T cell response on a small number of stimulatory determinants, the priming combination has been selected so that responders and stimulator express DR variants which only differ by three amino acids. With this protocol, the T cell response can be focused on a limited and precisely defined molecular difference and, thereby, restrict the heterogeneity of that response. On a functional level, the specificity and heterogeneity of alloreactive T cell clones generated with this priming combination will be characterized using an HLA-typed panel and monoclonal antibody blocking studies. On a molecular level, heterogeneity of the T cell response and specific T cell receptor gene usage will be studied by cDNA sequencing of variable regions of T cell receptor alpha and beta genes. Segments, if any, which are differentially utilized will be examined using hybridization studies with cloned genes and sequence specific probes and DNA sequence analysis to detect deletion or alteration of genetic segments in one of the responders.