1型糖尿病人来源胰岛素原特异性T细胞克隆的建立及表型鉴定

目的]研究1型糖尿病相关的胰岛素原(Proinsulin,PI)T细胞表位。方法]采用有限稀释法建立糖尿病病人胰岛素原抗原特异性的T细胞克隆,~(51)Cr释放细胞毒性试验测定T细胞激活的HLA限制性和PI肽段中最小的抗原表位,用流式细胞仪分析其表型及表面肿瘤坏死因子凋亡诱导配体(tumor necrosis factor-related apopto-sis-inducing ligand,TRAIL)的表达。结果]建立了PI抗原特异性的CD4~+ T细胞克隆TWHPI-1,CD8~+ T细胞克隆TWH PI-2。前者为HLA DRB4 0101限制,PI最小抗原表位在PI(79～87),74.2％细胞表达 TRAIL。后者为HLA A1限制。PI最小抗原表位在PI(78～86),94.9％细胞表达TRAIL。结论]HLA DRB4 0101-Al可能参与IDDM的致病过程,TRAIL可能是两株T细胞克隆引起胰岛细胞死亡的因子之一。

Establishment of T Cell Clones Specific to Proinsulin (PI) from A Patient with type 1 Diabetes Mellitus and Study of Its Phenotypes

Objective] To characterize human proinsulin protein T cell epitopes in insulin-dependent diabetes mellitus( IDDM). Methods] Limiting dilution was used to clone PI peptide reactive lymphocytes. Using a panel of B cell lines with different HLA phenotypes as targets and a family of PI peptides in 51 Cr release cytotoxicity assays to identify HLA restrictive elements of the T cell clones and minimal T cell epitope recognized by the T cell clone. The phenotypes and TRAIL(TNF-related apop-tosis-inducing ligand) were tested by flow cytometric analysis. Results] A CD4+ T cell clone named TWH PI-1 and a CD8+ T cell clone named TWH PI-2 specific to PI protein antigen were isolated. The TWH PI-1 CD4+ T cell clone specific to PI (79-87) was found to be restricted by HLA DRW 0101. On 74.2 % T cell surface there was TRAIL. The TWH PI-2 CD8+ T cell clone specific to PI ( 78-86) was found to be restricted by HLA A1. There was TRAIL on 94.9 % T cell surface. Conclusion] These results demonstrate that a tandem of DRB4 0101-Al] might predispose to the development of IDDM in this patients. TRAIL might be one of factors involved to islets cell destruction.