S180腹水癌小鼠肿瘤浸润淋巴细胞中CD4+CD25+Treg细胞在肿瘤逃逸中的作用

目的：研究肿瘤浸润淋巴细胞（TIL）中CD4⁺CD25⁺Treg细胞及免疫监视功能的变化，探讨CD4⁺CD25⁺Treg 细胞在肿瘤免疫逃逸中的作用。方法：建立小鼠S180腹水癌模型，采集S180腹水癌小鼠TIL、脾脏细胞及对照组小鼠脾脏细胞，采用流式细胞术检测CD4⁺CD25⁺Treg细胞、CD8⁺T细胞、NK细胞的数量及NKG2D的表达水平，采用RT-PCR方法检测Foxp3 mRNA的表达水平，采用乳酸脱氢酶(LDH) 释放法检测CD8⁺T细胞的杀伤功能。结果：与对照组小鼠比较，S180腹水癌小鼠脾脏、TIL中CD4⁺CD25⁺Treg细胞数量和Foxp3 mRNA表达均明显增高(P<0.05)，并且肿瘤组小鼠TIL中CD4⁺CD25⁺Treg细胞数量和Foxp3 mRNA表达较肿瘤组小鼠脾脏均明显增高(P<0.05)；TIL中CD8⁺T细胞数量明显增高(P<0.05)，其杀伤功能却有所下降；TIL中NK细胞数量及NKG2D表达均明显增高 (P<0.05)。结论：肿瘤局部CD4⁺CD25⁺Treg细胞数量增加、功能增强，可能是肿瘤逃避免疫监视的机制之一。

Function of CD4~+CD25~+Treg cells of tumor infiltrating lymphocytes in S180 ascites carcinoma mice in tumor immune escape

Objective To study the changes of CD4+CD25+Treg cells and immune surveillance function in tumor infiltrating lymphocytes(TIL)and investigate the relationship between CD4+CD25+Treg cells and tumor immune escape.Methods TIL and spleen cells of the S180ascites carcinoma mice and spleen cells of the control ones were used for the following detection:the quantities of CD4+CD25+Treg cells,CD8+T cells,NK cells and NKG2D were detected by flow cytometry;the expression level of Foxp3 mRNA was detected by RT-PCR;the k...