IL-6抑制LPS诱导的小鼠髓源性DCs成熟的实验研究

Suppression effect of IL-6 on the maturation of mouse bone marrow derived dendritic cells induced by LPS

目的观察白细胞介素-6(IL-6)对于内毒素(LPS)诱导的小鼠髓源性树突状细胞(DC)成熟效应的抑制作用。方法分离小鼠骨髓细胞,采用黏附法结合GM-CSF和IL-4刺激法在体外培养髓源性DCs(BMDCs)。用相差倒置显微镜观察BM-DCs的形态特点。用LPS诱导DC成熟。采用FACS结合混合淋巴细胞反应,观察IL-6处理与否,LPS诱导的BMDCs在表型和刺激同种淋巴细胞增殖功能上的变化。结果形态观察和FACS分析的结果表明:体外成功培养了纯度较高的高表达CD11c的BMDCs,LPS能明显诱导BMDCs表面MHC-Ⅱ类分子和共刺激分子CD40的表达上调;而经过IL-6处理后,LPS诱导BMDCs表面CD80、CD86、CD40表达上调的能力被显著削弱(P<0.05)。混合淋巴细胞反应显示,与单独用LPS处理的BMDCs相比,经IL-6处理后的BMDCs刺激同种淋巴细胞增殖的能力明显减弱,并呈剂量依赖关系(P<0.05)。结论IL-6能明显抑制LPS诱导的BMDCs成熟,可能是肿瘤免疫逃逸的重要机制之一。

Objective To explore the suppression effect of IL-6 on the maturation of mouse bone marrow-derived dendritic cells （BMDCs） induced by LPS. Methods To obtain immature BMDCs,mouse bone marrow cells were isolated and cultured in complete culture medium containing GM CSF and IL-4 following the removement of the nonadherent cells. The cell morphology was observed by using a phase contrast inverted microscope. The maturation of BMDCs was induced by LPS. The expression of surface costimulation molecules on LPS-treated BMDCs with or without IL-6 treatment was analyzed by fluorescence activated cell sorter（FACS）. The stimulation ability on allogeneic T ceils of LPS-treated BMDCs in the presence or absence of IL-6 was evaluated by allogenic mixed lymphocyte reaction（MLR）. Results DCs were generated from mouse bone marrow with normal morphology and high purity. Compared with BMDCs incubated with LPS only, LPS-treated DCs cultured in the presence of IL-6 expressed much lower levels of CD40,CD80 and CD86,and exhibited much weaker activity in stimulating the proliferation of allogeneic T cells（P〈0.05）. Conclusion If. 6 exerts a negative effect on the maturation and immunologic functions of BMDCs induced by LPS.