淋巴瘤细胞EL-4培养上清液对CD4＋CD25＋调节性T细胞比例的调节作用

目的探讨肿瘤细胞是否能上调CD4＋CD25＋调节性T细胞（Treg细胞）的比例。方法将小鼠淋巴瘤细胞株EL4培养上清液与正常小鼠脾脏淋巴细胞混合培养72h，流式细胞仪检测其中CD4＋CD25＋Treg细胞含量，RT—PCR检测Foxp3mRNA的表达，实验重复3次。结果和EL-4培养上清液混合培养的正常小鼠脾脏淋巴细胞中CD4＋CD25＋Treg细胞的比例高于对照组（P〈0．05），在CD3单抗刺激的同时加入EL-4培养上清液后，小鼠脾脏中CD4＋CD25＋Treg细胞仍呈同步增加（P〈0．05）；且Foxp3mRNA的表达增加。结论淋巴瘤细胞分泌的免疫调节因子能诱导CD4＋CD25＋Treg细胞的增生，提示肿瘤可以上调CD4＋CD25＋Treg细胞比例。

Up-regulate of the proportion of CD4+CD25+ regulatory T cells by lymphoma cell EL-4 supernatants

Objective To explore if the tumor cell can up-regulate the proliferation of CD4+CD25+ Treg cells. Methods Lymphoma cell EL-4 supernatant was combined with the normal mise spleen lymphocyte. After cultured 72 hours, CD4+CD25+ subset were analyzed by flow cytometry and the gene expression level of the specific marker Foxp3 were tested by RT-PCR. The experiment repeated three times. Results The supematant derived from EL-4 can increase the proportion of CD4+CD25+ Treg cells in normal mouse spleen lymphocytes than that of the control group. Moreover, when added the CD3 McAb with EL-4 supematant together, the number of CD4+CD25+ Treg cells increased. The level of corresponding Foxp3 mRNA also increased. Conclusion These data suggested that in the supernatant may occur immune regulatory factors which up-regulated the number of CD4+CD25+ Treg cells and indicated that the tumorigenesis can facilitate proliferation of CD4+CD25+ Treg cells.