霉酚酸酯对血管内皮细胞与淋巴细胞粘附及其表达CD40L的影响

The effects of mycophenolate mofetil on the expression of CD40L molecule by activated HUVEC

目的:观察霉酚酸酯(MMF)对细胞因子刺激下人脐静脉内皮细胞(HUVEC)CD40L的影响。方法:正常分娩人脐带经胶原酶消化后,分离出内皮细胞,培养至3～5代,用于细胞粘附和CD40L表达试验。以TNF-α和/或霉酚酸(MPA)处理HUVEC20小时后,用虎红法研究对淋巴细胞与内皮细胞粘附作用。以TNF-α、rIFN-γ、LPS分别和MPA同时作用HUVEC24小时。加不同浓度的MPA与LPS诱导HUVEC24小时,用Cell-ELISA检测CD40L的表达。结果:(1)MMF能抑制静息及TNF-α激活的内皮细胞与淋巴细胞间的粘附作用。(2)三种细胞因子均可明显诱导内皮细胞表达CD40L分子。(3)MMF不能抑制静息状态下内皮细胞CD40L的表达,但抑制TNF-α、rIFN-γ和LPS诱导CD40L的表达作用,且MMF抑制LPS诱导的内皮细胞CD40L表达呈剂量依赖效应。结论:MMF通过抑制内皮细胞表达CD40L而影响淋巴细胞与内皮细胞的相互作用,这可能是MMF抗排斥反应机制之一。

Objective： To investigate the effects of mycophenolate mofetil （MMF） on the expression of endothelial CIMOL and lymphocyte-endothelium adhesion. Methods：HUVEC was used for adhesion assay and CD40L detection. The effect of mycophenolic acid （MPA）, an active metabolite of MMF,was observed in the study. HUVEC were treated with TNF-α or/and MPA for 24 hours. The lymphocyte-endothelium adhesion was detected by Rose Bengal staining. After treated with TNF-α, rIFN-y, and LPS, HUVEC CIMOL expression was detected. HUVEC was treated with any of the mod^ators or each combined with MPA, respectively for 24 hours and different doses of MPA combined with LPS were also designed to stimulate HUVEC for 24 hours.The expression of CD40L on HUVEC was detected by cell-ELISA method.Results： MPA inhibited adhesion to lymphocytes of the HUVECs of either resting or stimulated with TNF-α. The cytokines used in the study induced expression of CD40L on HUVECs. MPA did not inhibit CD40L expression on resitng HUVECs, whereas it inhitbited CD40L expression induced by TNF-α, rlFN-γ,or LPS,and the inhibition of CIMOL expression on the cells induced by LPS was shown in dose of MMF-dependnet pattern. Conclusion： Endothehal cells express a low level of constitutive CD40L that is increased by treated with simple cytokines. MMF inhibits interactions between endothelial cells and lymphocytes by suppressing the expression of CD40L on endothelial cells.