中文摘要：

探讨Mce4E蛋白在牛结核分枝杆菌致病机理中的作用。以Mce4E蛋白刺激肺泡巨噬细胞24和48h后，MTT检测分析表明。Mce4E蛋白对巨噬细胞的活性有显著的抑制作用（P〈0．05）；用重组表达的Mce4E蛋白、人分枝杆菌纯化蛋白衍生物（Purified Protein Derivative of M．tuberculosis，MtbPPD）、牛结核分枝杆菌纯化蛋白衍生物（Purified Protein Derivative of M．bov／s，MbPPD）、卡介苗（Bacille Calmette Guerin，BCG）和刀豆蛋白A（concanavalin A,ConA）分别刺激肺泡巨噬细胞48h后，real—time PCR方法检测显示，Mce4E蛋白能够促使牛肺泡巨噬细胞TNF-α和IL-6mRNA的表达上调（P〈0．05）、抑制肺泡巨噬细胞iNO的mRNA表达（P〈0．05）而对IL-12表达没有影响（P〉0、05）。Mce4蛋白能够促使肺泡巨噬细胞分泌炎性细胞因子。并对肺泡巨噬细胞有抑制作用，证实Mce4蛋白在分枝杆菌中具有重要的作用。

英文摘要：

A large body of research has confirmed that mammalian cell entry proteins （Mce） are related to the virulent Mycobacterium bovis. MTT （3, （4, 5 dimethylthiazol-2yl）-2, 5 diphenylc-tetrazolium bromide） analysis showed that Mce4E protein could inhibit macrophage activity. In real-time RT-PCR assay, Mce4E protein stimulated alveolar macrophage for 48 hours, which significantly （P 〈 0.05） induced the expression of TNF-α and enhanced IL-6 mRNA but the expression of iNO was reduced （P〈 0.05）. There was no effect on the IL-12 expression in the macrophage. We conclude that Mce4E proteins can induce an inflammatory response on exposure to M. boris and therefore play an important role in the immune response.