Oling Viveka, Marttila Jane, Ilonen Jorma, Kwok William W, Nepom Gerald, Knip Mikael, Simell Olli, Reijonen Helena
Department of Virology, University of Turku, Medicity, Biocity 4 krs., Tykistökatu 6 A, 20520 Turku, Finland.
J Autoimmun. 2005 Nov;25(3):235-43. doi: 10.1016/j.jaut.2005.09.018. Epub 2005 Nov 2.
In type 1 diabetes the major loss of insulin producing beta-cells is caused by autoreactive T-cells specific for antigens expressed by the pancreatic islets. In this study we have analyzed the prevalence of glutamate decarboxylase 65 (GAD65)- and proinsulin-specific CD4(+) T-cells in type 1 diabetes patients, at-risk subjects and in HLA-matched control children. Peripheral blood mononuclear cells were cultured in the presence of two different GAD65 peptides (555-567, 557I and 274-286) or with a proinsulin (B24-C36) peptide for 10-11days. The autoreactive T-cells were detected using antigen specific-MHC class II tetramers by flow cytometry. Our results show that 11 of 18 (61%) type 1 diabetes patients and 7 of the 20 (35%) at-risk subjects were positive for one of the three GAD65 or proinsulin-containing tetramers, whereas only 2 of 21 (9.5%) controls had tetramer binding cells (p = 0.0007 type 1 diabetes vs. controls and p = 0.0488 at-risk subjects vs. controls, Chi-square test). Type 1 diabetes patients responded to all three peptides. At-risk subjects recognized also the GAD65 555-567 557I peptide, while none of the controls responded to it. In conclusion, type 1 diabetes patients and at-risk subjects have a significantly higher prevalence of GAD65- and proinsulin-specific CD4(+) T-cells than the control subjects.
在1型糖尿病中，产生胰岛素的β细胞的主要损失是由对胰岛表达的抗原具有自身反应性的T细胞引起的。在本研究中，我们分析了1型糖尿病患者、高危人群以及HLA匹配的对照儿童中谷氨酸脱羧酶65（GAD65）特异性和胰岛素原特异性CD4(+) T细胞的患病率。外周血单个核细胞在两种不同的GAD65肽（555 - 567、557I和274 - 286）或胰岛素原（B24 - C36）肽存在的情况下培养10 - 11天。通过流式细胞术使用抗原特异性MHC II类四聚体检测自身反应性T细胞。我们的结果显示，18例1型糖尿病患者中有11例（61%）以及20例高危人群中有7例（35%）对三种GAD65或含胰岛素原的四聚体中的一种呈阳性，而21例对照中只有2例（9.5%）有四聚体结合细胞（1型糖尿病患者与对照相比，p = 0.0007；高危人群与对照相比，p = 0.0488，卡方检验）。1型糖尿病患者对所有三种肽都有反应。高危人群也识别GAD - - 65 555 - 567 557I肽，但对照中无人对此有反应。总之，1型糖尿病患者以及高危人群体内GAD - - - 65特异性和胰岛素原特异性CD4(+) T细胞的患病率显著高于对照人群。
