肿瘤免疫主要由细胞免疫介导，研究证实抗原特异性Ｔ细胞的活化需要共刺激信号的参与，缺乏共刺激信号将导致受抗原刺激的Ｔ细胞发生免疫无能，耐受甚至凋亡。Ｂ７．１是目前研究最多也是最重要的共刺激分子，已有的动物实验证明肿瘤细胞缺乏Ｂ７．１表达是其逃逸免疫监视... Tumor immunity is mainly mediated by cellular immunity. Studies have confirmed that the activation of antigen-specific T cells requires the participation of co-stimulatory signals. The lack of co-stimulatory signals will lead to immunosuppression, tolerance, and even apoptosis of antigen-stimulated T cells. B7.1 is currently the most studied and most important co-stimulatory molecule, and existing animal experiments have proven that tumor cells lack B7.1 expression is its escape immune surveillance...