STRUCTURE AND FUNCTION OF TOXIC SHOCK SYNDROME TOXIN 1

中毒性休克综合征毒素 1 的结构和功能

• 批准号: 2065775
• 负责人: EDMUND M CHOI
• 金额: $ 13.05万
• 依托单位: UNIVERSITY OF CINCINNATI
• 依托单位国家: 美国
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-07-01 至 1996-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2065775
• 关键词: MHC class II antigen; Staphylococcus aureus; T cell receptor; T lymphocyte; chemical structure function; epitope mapping; gene mutation; human tissue; interleukin 1; laboratory mouse; leukocyte activation /transformation; macrophage; molecular cloning; neutralizing antibody; site directed mutagenesis; staphylococcal exotoxin; superantigens; tissue /cell culture; toxic shock syndrome; tumor necrosis factor alpha

Toxic shock syndrome toxin-1 (TSST-1) has been strongly implicated in the pathogenesis of toxic shock syndrome, an acute onset multisystem disorder. this staphylococcal exotoxin triggers the activation of T- lymphocytes and macrophages resulting in the induction of cytokines. The potent immunomodulatory effects of this toxin is likely to be a key factor in the pathogenesis of toxic shock syndrome. The overall goal of this proposal is to define structure-function correlations for the various biologic effects of the toxin using mutational analysis. Mutant TSST-1 toxins will be generated using site-directed mutagenesis on the cloned gene. Mutant TSST-1 will be tested for the ability to induce cytokine secretion by macrophages and to activate T-cells. This approach can be used to determine whether functionally distinct sites exist on the toxin molecule. The mutant toxins will also be used to study the interaction between TSST-1, the T-cell receptor (TCR) and the MHC class II molecules, a critical event in the initiation of T-cell mitogenesis by TSST-1. The TSST-1 mutants will be tested for the ability to bind to class II MHC molecules. Conversely, cell lines expressing mutant class II MHC antigens will be used to define the sites on the class II molecule that interact with native TSST-1. T-cell receptor interactions with TSST-1 will be studied by comparing the TCR-Vbeta genes expressed on T- cells activated by mutant TSST-1 with those selected by the wild-type TSST-1. This selective activation of T-cells bearing particular subsets of Vbeta elements is characteristic of the TSST-1 "superantigen". In summary, the proposed work will define sites on TSST-1 molecule which are critical for toxin-mediated effects on T-cells and macrophages. Molecular interactions between the cellular receptors and the TSST-1 toxin will also be characterized. This information can ultimately be used to understand the relative contribution of TSST-1 functions in the pathogenesis of toxin shock syndrome.

中毒性休克综合征毒素-1（TSST-1）与 中毒性休克综合征的发病机制 disorder. 这种葡萄球菌外毒素触发T细胞活化， 淋巴细胞和巨噬细胞，导致细胞因子的诱导。 的 这种毒素强大的免疫调节作用可能是 中毒性休克综合征的发病机制中的因素。 的总目标 这个建议是为了定义结构-功能相关性， 毒素的各种生物学效应。 突变体 TSST-1毒素将使用定点诱变产生。 克隆基因 将检测突变体TSST-1诱导 通过巨噬细胞分泌细胞因子并激活T细胞。 这种方法 可以用来确定是否存在功能不同的网站上， 毒素分子 突变毒素也将用于研究 TSST-1、T细胞受体（TCR）和MHC类之间的相互作用 II分子，T细胞有丝分裂起始的关键事件 TSST-1。 将测试TSST-1突变体结合TSST-1的能力。 II类MHC分子。 相反，表达突变型类 II类MHC抗原将用于定义II类分子上的位点 与天然TSST-1相互作用。 T细胞受体与 TSST-1将通过比较T细胞上表达的TCR-V β基因进行研究。 突变TSST-1激活的细胞与野生型选择的细胞 TSST-1。 这种带有特定亚群的T细胞的选择性激活 是TSST-1“超抗原”的特征。 在 总之，所提出的工作将确定TSST-1分子上的位点， 对于毒素介导的对T细胞和巨噬细胞的作用至关重要。 细胞受体与TSST-1之间的分子相互作用 毒素也将被表征。 这些信息最终可以 用于了解TSST-1功能在 毒素休克综合征的发病机制