目的：探究调节性T细胞在自身免疫性干眼发病中的作用，并对泪液系统内调节性T细胞及相关细胞因子的表达做出分析，为自身免疫性干眼病的治疗提供更加有效的治疗方案。

方法：单独培养提纯分离出的兔泪腺上皮细胞一段时间后，将其与分离出的外周血淋巴细胞以1：1的比例混合进行培养，并用5-脱氧尿嘧啶核苷(5-Bromo-2-deoxyUridine，BrdU)检测外周血淋巴细胞的增殖情况，将已激活的自体外周血淋巴细胞通过耳缘静脉回输供体兔体内，回输细胞后的供体兔将作为兔自身免疫性干眼模型组，未诱导发病的正常兔个体为对照组，观察实验前后兔角膜染色和2、4、6、8wk的泪膜破裂时间、泪液的分泌等情况，回输细胞4wk后处死，收集双侧上下泪腺和结膜，并进行病理HE染色，然后提取泪腺组织中的总RNA，检测IL-17、TNF-α、IL-6、TGF-γ的表达。

结果：BrdU检测出的外周血淋巴细胞增值比率为3.72，激活的外周血淋巴细胞回输体内会诱导产生兔自身免疫性干眼，与正常组比较，泪膜破裂时间减少，且差异具有统计学意义(P<0.05)； 模型组较对照组泪液分泌显著减少，且差异具有统计学意义(P<0.05)； HE染色显示在回输细胞4wk后，结膜组织和泪腺均有淋巴细胞浸润，检测发现模型组IL-17、TNF-α、IL-6、TGF-γ的表达较对照组均有所增加，但IL-10、TGF-β的表达较对照组有所降低，且差异具有统计学意义(P<0.05)； 流式细胞术检测表明，在对照组中，泪腺组织和脾脏中CD4⁺CD25⁺Treg细胞比例较高，模型组CD4⁺CD25⁺Treg细胞比例有所降低，且差异具有统计学意义(P<0.05)。

结论：兔干眼模型发病时，CD4⁺CD25⁺Treg细胞免疫抑制作用下降，IL-17、TNF-α、IL-6、TGF-γ等细胞因子在泪腺的炎症反应中都发挥着重要作用。

AIM: To investigate the role of regulatory T cells in the pathogenesis of autoimmune dry eye and to analyze the expression of endogenous regulatory T cells and related cytokines in the lacrimal system to provide a more effective treatment for autoimmune dry eye disease treatment programs.

METHODS: Rabbit lacrimal gland epithelial cells isolated and cultured for a period of time were separately cultured and mixed with isolated peripheral blood lymphocytes in a ratio of 1: 1 and cultured with 5-Bromo-2-deoxyUridine(BrdU)to detect the proliferation of peripheral blood lymphocytes, and the activated autologous peripheral blood lymphocytes were transferred to donor rabbits via ear vein. The rabbits were used as the rabbit model of autoimmune dry eye and the normal rabbits which did not induce the disease as the control group. Before and after the experiment, tear film rupture time and tear secretion at 2,4,6,8wk,were observed. At 4 wk after the transfusion the rabbits were sacrificed for the collection of bilateral upper and lower lacrimal gland and conjunctiva, and pathological HE staining, and then extract the total RNA in lacrimal gland. The expression of IL-17, TNF-α, IL-6 and TGF-γ was detected.

RESULTS: BrdU detected peripheral lymphocyte proliferation rate of 3.72. Compared with the normal group, the time of rupture of the tear film decreased(P<0.05), and the tear of the model group was significantly lower than that of the control group(P<0.05). The expression of IL-17, TNF-α, TGF-γ and IL-6 in the model group were significantly higher than those in the control group(P<0.05). The expression of IL-10 and TGF-β was significantly lower than those of the control group(P<0.05). The ratio of CD4⁺ CD2⁺ Treg cells in lacrimal gland tissue and spleen was higher in control group. The proportion of CD4⁺CD25⁺ Treg cells in model group decreased(P<0.05).

CONCLUSION: IL-17, TNF-α, IL-6 and TGF-γ play important roles in inflammatory reaction of lacrimal gland and the immunodepression active by CD4⁺CD25⁺Treg cells decreases when the rabbit model of dry eye is involved.