集聚蛋白在淋巴细胞活化中的作用

The role and mechanisms of agrin in the activation of lymphocytes

目的研究在神经突触形成中发挥重要作用的集聚蛋白(agrin)是否在淋巴细胞中表达并影响淋巴细胞的活化和免疫突触的形成。方法应用RT-PCR检测集聚蛋白在静止和活化淋巴细胞中的表达,并应用实时定量PCR检测分析集聚蛋白的表达量与淋巴细胞活化之间的关系;用抗集聚蛋白抗体观察其对淋巴细胞增殖和免疫突触形成的影响;应用共聚焦显微镜观察集聚蛋白是否参与免疫突触的形成。结果RT-PCR结果显示集聚蛋白在静止和活化的淋巴细胞中均有表达,且经过实时定量PCR分析发现,集聚蛋白的表达和淋巴细胞的活化密切相关;当集聚蛋白被阻断后淋巴细胞的增殖被显著抑制;经共聚焦显微镜观察发现,集聚蛋白在活化的淋巴细胞中以帽化结构形式存在,且和CD3分子共定位,抗集聚蛋白抗体可以明显减少这种帽化结构的形成。结论在神经突触中发挥重要作用的集聚蛋白同样存在于淋巴细胞,可能通过影响淋巴细胞的免疫突触的形成参与淋巴细胞的活化。

Objective To investigate whether agrin, a key protein in formation of neurological synapse, is expressed in lymphocytes and activate lymphocyte through affecting the formation of immunological synapse. Methods RT-PCR was performed to detect the expression of agrin in resting and activated lymphocyte; real time PCR was conducted to analyze the correlation between agrin expression and lymphocyte activation status; ^3 H-TdR incorporation assay was used to evaluate the effect of agrin on activation of lymphocyte; and confocal microscopy was used to identified the agrin location on membrane of lymphocyte. Results Agrin was expressed in both resting lymphocytes and activated lymphocytes. The expression was directly correlated with status of lymphocyte activation. Lymphocyte activation was inhibited by antibody against agrin. In activated lymphocytes agrin was co-capping with CD3 molecules and this capping - like structure formation was interfered by antibody against agrin . Conclusion Agrin plays a role in activation of lymphocyte and formation of immunological synapse.