BINDING OF PEPTIDES TO MHC MOLECULES

这项工作的目的是了解的细节， 研究了自身和外源肽与MHC分子的相互作用， 通过体外结合方法和通过T细胞活化测定。 随着这个项目的发展，我们开发了一个系统， 抗原肽与MHC I类分子H-2Ld的结合是 测量，在其中我们可以并行测量的相互作用， MHC/肽复合物与T细胞受体。 目前的实验有 研究了辅助受体分子CD 8对 MHC/TCR相互作用以及早期信号事件的性质 由肽/MHC刺激T细胞引起 复合物和含有变体肽的那些。 注意力一直集中在一个矛盾的结果： 与小鼠MHC I类复合的单一肽变体 分子H-2Ld，作为一种有效的敏化肽，但未能 形成一个复合物，我们可以检测到表面等离子体的结合， 共振 变异肽似乎形成了一种复合物， T细胞的细胞溶解，淋巴因子的产生，或者现在，如研究 博士M. Jelonek与I博士合作。Stefanova早期 磷酸化事件。 由于在这方面存在着这样的差异， 变体肽/H-2Ld复合物体外结合TCR的能力 值得注意的是，T细胞反应似乎只显示出轻微的 早期磷酸化模式的动力学和定量差异。 试图评估CD 8（由澳大利亚生产）的贡献， 合作者Brendan Classon和Peter哈德逊）的结合反应 H-2Ld/肽复合物与同源TCR的相互作用揭示了 CD 8为H-2Ld分子缺乏肽。 这表明， 在CD 8蛋白的氨基末端区域中的H-2Ld肽基序是 通过MHC的肽结合介导与MHC分子的结合 凹槽 各种直接结合和竞争实验 证实了H-2Ld可以进行这种模式的结合成熟的 CD8。

The objective of this work has been to understand the details of the interaction of self and foreign peptides with MHC molecules, as studied both by in vitro binding methods and by assays of T cell activation. As this project has developed, we have developed a system in which the binding of the antigenic peptide to the MHC class I molecule H-2Ld is measured and in which we can in parallel measure the interaction of the MHC/peptide complex with the T cell receptor. Current experiments have investigated the influence of the coreceptor molecule, CD8, on the MHC/TCR interaction as well as the nature of the early signaling events that are elicited by the stimulation of the T cell with peptide/MHC complexes and those containing variant peptides. Attention has been focused on a paradoxical result: the identification of a single peptide variant that complexes with the mouse MHC class I molecule H-2Ld, serves as an effective sensitizing peptide, but fails to form a complex in which we can detect binding by surface plasmon resonance. The variant peptide seems to form a complex that activates the T cells to cytolysis, lymphokine production, or now, as studied by Dr. M. Jelonek in collaboration with Dr. I. Stefanova by early phosphorylation events. Since there has been such a discrepancy in the ability of the variant peptide/H-2Ld complex to bind the TCR in vitro it is remarkable that the T cell response seems to show only minor kinetic and quantitative differences in early phosphorylation patterns. Attempts to evaluate the contribution of CD8 (produced by Australian collaborators Brendan Classon and Peter Hudson) to the binding reaction of H-2Ld/peptide complexes with the cognate TCR revealed interaction of the CD8 to H-2Ld molecules devoid of peptide. This suggested that an H-2Ld peptide motif in the amino terminal region of the CD8 protein was mediating binding to the MHC molecule through the MHC's peptide binding groove. A variety of direct binding and competition experiments have confirmed that H-2Ld can carry out this mode of binding to the mature CD8.