中文摘要：

目的研究脂多糖（LPS）刺激对1,25-二羟维生素D3处理的树突状细胞表型及功能的影响。方法10-8 mol／L1，25-二羟维生素D3处理的不成熟树突状细胞经LPS刺激活化24h，倒置显微镜观察其形态学，流式细胞仪检测其表面共刺激分子CD80、CD86、CD40及MHCⅡ表达，ELISA方法检测其分泌IL-12p70及IL-10水平，混合淋巴细胞反应法测定其刺激同种异体T细胞增殖的能力。结果脂多糖刺激1，25-二羟维生素D3处理的树突状细胞形态类似于不成熟DC形态，表面共刺激分子CD86及MHCⅡ高表达，抑制IL-12p70分泌，促进IL-10分泌，抑制同种异体CD4＋T 细胞增殖。结论1，25-二羟维生素D3处理的树突状细胞显示了耐受性树突状细胞特性，能抑制脂多糖驱动的CD4＋T细胞增殖，这为研究1，25-二羟维生素D3处理的树突状细胞诱导免疫耐受治疗哮喘等自身免疫性疾病奠定了基础。

英文摘要：

This study designed to investigate the effects of LPS stimulation on phenotype and functions of 1, 25-dihydroxyvitamin D3 （1, 25（OH）2D3）-treated dendritic cells （DC） in vitro. Firstly, 1, 25（OH）2D3-treated DC （10-8 mol/L） were stimulated by LPS for 24 hours. Then the morphology of DC was observed by inverted microscopy; the expression of co-stimulatory molecules （CD80, CD86, and CD40） and MHC class Ⅱ was determined by flow cytometry; the levels of IL-12p70 and IL-10 were analyzed by ELISA. Furthermore, the capability of stimulating allogeneic CD4＋T ceil proliferation was measured by MLR （mixed lymphocyte reaction）. 1, 25 （OH）2D3-treated DC stimulated by LPS exhibited features of inmature DC with high expression of co- stimulatory molecules CD86 and MHC class Ⅱ, inhibiting the secretion of IL-12p70, enhancing the secretion of IL-10, and suppressing allogeneic CD4CF cell proliferation. Results in this study indicate that 1, 25（OH）2D3-treated DC have the character of tolerogenic DCs, which can inhibit LPS-drived proliferation of CD4 ＋T cells, which should be a foundation for study of 1, 25（OH）2D3-treated DCs inducing immunotolerance and the treatment of autoimmune disease such as asthma.