恒定自然杀伤T细胞与肿瘤免疫治疗

恒定自然杀伤T细胞(iNKT)是T淋巴细胞的一个独特亚群，兼具自然杀伤(NK)细胞和T细胞特征，同时表达T细胞受体(TCR)和NK细胞表面标志。iNKT细胞被激活后，通过分泌细胞因子，活化其它免疫细胞参与先天性免疫和获得性免疫，在抗肿瘤免疫过程中发挥调节作用。在多种癌症患者体内，发现外周血中iNKT细胞的数量降低、功能减弱，进而导致临床治疗效果不佳。近年来，基础研究和早期临床试验结果表明，注射抗原递呈细胞或/和体外培养并活化的iNKT细胞，抗肿瘤免疫治疗效果显著。本文就iNKT细胞的分类及生物学特性，在肿瘤免疫治疗中的作用与其机制，以及其临床应用等进行综述。

Invariant Natural Killer T Cells and Tumor Immunotherapy

Invariant natural killer T (iNKT) cells constitute a distinct T lymphocyte subset characterized by the expression of an invariant T-cell receptor (TCR) and natural killer(NK) receptors. After activation，iNKT cells are involved in the innate immunity and adaptive immunity by secreting cytokines to activate other immune cells, which play a regulatory role in the anti-tumor immune responses. Recent results showed that quantitative and qualitative defects in the iNKT-cell pool have subsequently been observed in many cancer patients, thus correlating with a poor clinical outcome. Early basic researches and clinical trials about cellular immunotherapy with antigen presenting cells or activated iNKT cells had been completed and showed significant anti-tumor responses. In this article, the classification, biological characteristics of iNKT cells and the functions and the mechanism as well as the clinical applications in tumor immunotherapy were reviewed.