PD-1/PD-L1信号通路及其在肿瘤免疫治疗中的作用

抑制性共刺激分子程序性死亡因子1（PD-1）/程序性死亡因子配体1（PD-L1）是重要的负性免疫调节分子，在机体适应性细胞免疫中发挥着重要作用。表达PD-L1的肿瘤细胞可与T细胞表面受体分子PD-1特异性结合，从而影响T细胞的活化与分化，并抑制T细胞的抗肿瘤免疫杀伤活性。目前，已有多种靶向PD-1/PD-L1免疫检查点的药物应用于临床，并在不同类型的肿瘤治疗中显示出良好疗效。本文就PD-1/PD-L1的分子结构、表达特点、上调影响因素，以及其在促进肿瘤生长、免疫逃逸、肿瘤免疫治疗中的作用等方面的研究进展作一综述。
As negative immune regulatory molecules, the inhibitory co-stimulatory molecules programmed death 1 (PD-1)/programmed death ligand 1 (PD-L1) play important roles in the adaptive cellular immunity. PD-L1 expressed in tumor cells is involved in regulating T cell activation and differentiation and inhibiting the anti-tumor immune activity of T cell through specific binding with the receptor molecule PD-1 on T cells. Currently, a variety of agents targeting the immune checkpoints of PD-1/PD-L1 have been used in clinic, which have exhibited long-lasting effect in treatment for different types of tumors. In this review, we summed up the molecular structure, expression features, factors influencing upregulation of PD-1/PD-L1, and their roles in promoting tumor growth and escaping from immune system and tumor immunotherapy