ROLE OF B7 AND CYTOKINES IN REGULATION OF EAE

B7 和细胞因子在 EAE 调节中的作用

• 批准号: 6201301
• 负责人: VIJAY K. KUCHROO
• 金额: $ 22.66万
• 依托单位: BRIGHAM AND WOMEN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-09-01 至 2000-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6201301
• 关键词: T cell receptor; T lymphocyte; antigen presenting cell; autoantigens; cell differentiation; cytokine; enzyme linked immunosorbent assay; epitope mapping; experimental allergic encephalomyelitis; gene targeting; genetically modified animals; immunopathology; immunoregulation; laboratory mouse; protein biosynthesis

This proposal is based upon our observations that both B7 costimulatory molecules and altered forms of the encephalitogenic PLP 139-151 (HSLGKWLGHPDKF) peptide (termed altered peptide ligands, APL) can regulate experimental allergic encephalomyelitis (EAE) by affecting T cell differentiation and cytokine production. The basic theme of this proposal is to identify the mechanisms by which costimulatory B7 molecules and APLs may suppress autoantigen specific pro--inflammatory Th1 cells and enhance functions of antiinflammatory Th2 cells. We have recently generated PLP 139-151 specific Th2 clones which upon adoptive transfer prevent induction of EAE and reverse established disease. However, all the myelin antigen- reactive Th2 cells do not inhibit EAE, raising the critical question as to what are the requirements necessary for generating protective Th2 clones. We propose to i) determine the contribution of the epitopic structure recognized by the Th2 clones towards the protective phenotype. The protective PLP 139-151 specific Th2 clones that we have generated recognize l141/G142 as the primary TcR contract site as opposed to the encephalitogenic Th1 clones that recognize W144 as the primary TcR contract residue. Using our panel of Th2 clones as well as T cell clones generated from B7 deficient and CTLA4-Ig treated mice in project I, we will correlate the epitope specificity (L141/G142 or E1440 witha the protective phenotype. ii) Study the mechanism by which APL inhibit EAE by studying the nature (epitope specificity and cytokine profile) of T cell clones generated by immunization with the SAPL and testing the effects of these clones in regulating EAE upon adoptive transfer and examining the effects of the APL on inhibiting EAE in the B7-1, B7-2, IL-4 and IL-10 deficient mice. iii) study whether strength of signal/stimulus generated by the B7 molecules and APLs may be responsible for altering T cell differentiation and dictate whether a clone will become an encephalitogene Th1 cell or a regulatory Th2/TGFbeta producing cell. This will be accomplished by generating APC by transfection with varying levels of expression of B7-1, B7-2 and class II molecules. These artificial APCs together with different APLs will be utilized to activate T cell clones to correlate strength of signal with the production TH2 vs. Th1 cytokines. These results will provide broad basic information relevant to understanding the immunopathological events in MS and other diseases mediated by autoimmune mechanisms.

这个建议是基于我们的观察，即B7共刺激蛋白和B7共刺激蛋白都可以被激活。 致脑炎PLP 139-151的分子和改变形式 （HSLGKWLGHPDKF）肽（称为改变的肽配体，APL）可以调节 实验性变态反应性脑脊髓炎（EAE）通过影响T细胞 分化和细胞因子产生。 本提案的基本主题是 是为了确定共刺激B7分子和APLs 可抑制自身抗原特异性 促炎性Th 1细胞和增强 Th 2细胞的功能。 我们最近生成了PLP 139-151特异性Th 2克隆，其在过继转移时防止诱导 EAE和逆转已建立的疾病。 但是所有的髓鞘抗原- 反应性Th 2细胞不能抑制EAE，这引发了一个关键问题： 产生保护性Th 2克隆的必要条件是什么。 我们建议i）确定表位结构的贡献 被Th 2克隆识别为保护性表型。 的 我们产生的保护性PLP 139-151特异性Th 2克隆识别 l141/G142作为主要TcR合同地点，而不是 致脑炎性Th 1克隆识别W144作为主要的TcR合同 残余物 使用我们的一组Th 2克隆以及产生的T细胞克隆， 从项目I中B7缺陷和CTLA 4-IG治疗的小鼠中，我们将关联 表位特异性（L141/G142或E1440）为保护性表型。 ii）通过研究APL抑制EAE的性质，研究APL抑制EAE的机制。 表位特异性和细胞因子谱）的测定。 用SAPL免疫，并测试这些克隆在 在过继转移后调节EAE并检查APL的作用 在B7-1、B7-2、IL-4和IL-10缺陷小鼠中抑制EAE。 （三） 研究B7分子产生的信号/刺激的强度， APLs可能负责改变T细胞分化，并决定T细胞的分化。 克隆是否会成为致脑炎Th 1细胞或调节细胞， Th 2/TGF β产生细胞。 这将通过以下方式生成APC来实现： 用不同水平的B7-1、B7-2和II类 分子。 这些人造装甲运兵车与不同的杀伤人员地雷一起， 用于激活T细胞克隆，以将信号强度与T细胞克隆的表达相关联。 产生Th 2细胞因子与Th 1细胞因子。 这些结果将提供广泛的基础 与理解MS中免疫病理学事件相关的信息 和其他由自身免疫机制介导的疾病。