IDO介导肺癌细胞免疫逃逸的实验研究

Indoleamine 2, 3-Dioxygenase Activity in lung cancer Cells Contributing to Tumor Immune Escape

目的探讨吲哚胺2,3双加氧酶(IDO)介导肺癌的免疫逃逸机制。方法通过混合培养肺癌细胞A549和T淋巴细胞,RT-PCR检测IDOm RNA在细胞中的表达;以IL-2为细胞刺激因子,有或无1-甲基色氨酸(1-MT)条件下,建立单向淋巴细胞混合反应体系(MLR),MTT法检测T细胞活力,并采用ELISA试剂盒检测IDO活性。结果IDOm RNA在单独培养A549细胞中不表达,在T淋巴细胞中微量表达,而在A549细胞和T淋巴细胞的混合体系中高表达;而且混合单向淋巴细胞反应体系中,IDO的表达能够使T淋巴细胞增殖受到抑制。结论 A549细胞在混合培养体系中表达的IDO能有效抑制外周血T细胞增殖,可能参与肺癌免疫逃逸。

Objective Investigating the immune escape mechanism of 2- and 3-（IDO）- mediated lung cancer. Methods Lung cancer A549 cells and T lymphocytes were mixed culture and IDOm RNA expression was detected by RT-PCR; Then one-way lymphocytes mixed reaction（MLR） was carried out, cytokines IL-2 was used as stimulation in culture without or with 1-MT. MTT assay was used to detect the viability of T cells and IDO activity in ELISA kit. Results IDO expression was not found in A549 cells cultured alone, was expression of trace in T-lymphocyte, but IDO expression in mixed system of A549 cell A, and expression levels were separately cultured T lymphocytes. In mixed lymphocyte reaction of one-way, the expression of IDO can inhibit the proliferation of T lymphocytes. Conclusions The expression of IDO in mixed culture of A549 cells can inhibit the proliferation of T cells in peripheral blood,which may lead to immune escape of lung cancer.