自然杀伤细胞参与肝脏恶性肿瘤免疫逃逸研究进展

Involvement of Natural Killer Cells in Liver Tumor Immune Escape

自然杀伤细胞是机体固有免疫系统重要组成部分,在肝脏等免疫器官中含量丰富,而且免疫表型、功能等表现出器官特异性。在正常情况下,靶细胞表面的配体与自然杀伤细胞表面的活化性受体直接结合并释放细胞毒性物质,诱导活化靶细胞凋亡程序,从而发挥抗感染、抗肿瘤作用。然而肿瘤细胞仍能够通过多种途径逃逸机体的免疫监视功能,研究认为肿瘤细胞抗原异常表达、肿瘤微环境中细胞因子及其他免疫细胞相互作用等因素所引起的自然杀伤细胞活性降低对于诱导肿瘤免疫逃逸起重要作用。本文综述了自然杀伤细胞在肝脏恶性肿瘤发生过程中参与免疫逃逸的机制及研究进展,以期为临床抗肿瘤免疫治疗的研究提供参考。

Natural killer cells（NK） as the key components of the innate immune system are enriched in liver and have organ specificity on immunophenotype and function that show anti-infection and anti-tumor responses. Under normal circumstances, the stimulatory ligands expressed on the target cell interact with the activated receptors and stimulate NK cells to release cytotoxic substances and induce target cells apoptosis. However tumor cells are able to escape the immune surveillance of NK cells through a variety of ways.Over the past decade, growing evidence indicates that the abnormal expression of tumor-associated antigens, cytokines and interactions with other immune cells in the tumor microenvironment affected cytotoxic activity of natural killer cells, and played a central role in immune escape of tumor cells. This review focuses on recent studies about the natural killer cells involved in immune escape of liver tumor and may lead to provide reference points for antitumor therapeutic targets.