谷氨酸脱羧酶特异调节的T细胞抑制NOD小鼠的自身免疫性糖尿病

Inhibition of autoimmune diabetes in NOD mice by GAD-specific regulatory T cells

目的 探讨抗原特异调节的T细胞在非肥胖型糖尿病 (NOD)小鼠自发性糖尿病中的作用。方法 应用流式细胞计数仪辅以荧光标记组织相容性抗原Ⅱ类分子四聚体染色 ,从自发性糖尿病的NOD小鼠和非糖尿病的BALB/c小鼠中分离出谷氨酸脱羧酶 (GAD)多肽特异性T细胞。分别应用抗原刺激试验、酶联免疫反应、细胞内细胞因子染色检测上述T细胞的细胞因子表达。最后将上述T细胞给NOD/scid小鼠静脉注射 ,检测这些T细胞对糖尿病发生的影响。结果 当用不同多肽诱导同一品系时 ,NOD小鼠T细胞分泌不等量的干扰素 γ ,相似量的白介素 (IL) 4和IL 10 ;BALB/c小鼠T细胞分泌类似量的细胞因子。当同一多肽诱导不同品系时 ,NOD小鼠T细胞较BALB/c小鼠T细胞分泌较少量的IL 2但较大量的IL 4和IL 10。这些NOD小鼠T细胞均可以有效地抑制NOD/scid小鼠的糖尿病发生。结论 两种毗邻的GAD多肽诱导NOD小鼠产生的T细胞表达不同的细胞因子分泌类型 ,但这些NOD小鼠T细胞均可以有效地抑制NOD/scid小鼠的糖尿病 ,因此推论这些细胞为分泌独特细胞因子且抑制糖尿病的T调节细胞。

Objective To investigate the role of antigen-specific regulatory T cells in spontaneous diabetes of NOD mice. Methods Glutamic acid decarboxylase (GAD)-peptide specific T cells with fluorescein-labelled Class Ⅱ MHC tetramers were isolated by flow cytometer from NOD mice with spontaneous diabetes and diabetes resistant BALB/c mice. The cytokine profiles of these T cells were detected by antigen stimulated assay, ELISA and intracellular cytokine staining. Adoptively transferred diabetes was determined by intravenously injecting these T cells to NOD/scid mice. Results With different peptides working on the same strain, it showed that NOD mice-derived T cells secreted different amounts of interforn-γ but comparable interlenkin (IL)-4 or IL-10, however, similar cytokine profiles were shown in BALB/c mice-derived T cells. With the same peptide working on different strains, NOD mice-derived T cells secreted less IL-2 but more IL-4 and IL-10 than BALB/c mice-derived T cells did. Interestingly, these NOD mice-derived T cells effectively inhibited diabetes development in adoptively transferred NOD/scid mice. Conclusion NOD mice-derived T cells inhibit development of diabetes, however, different cytokine profiles are expressed by these T cells induced by two adjacent GAD peptides. It suggests that these T cells are diabetes-inhibiting regulatory T cells displaying unique cytokine profiles.