白细胞介素21（interleukin-21，IL-21）是由4个α螺旋束寡聚而成的Ⅰ型细胞因子，与IL-2、IL-4和IL-15高度同源，具有多重免疫调节作用。相关研究表明，IL-21与某些肿瘤密切相关。作为一种极具潜力的免疫调节剂，IL-21在肿瘤治疗中具有广阔的应用前景。IL-21与部分单克隆抗体联用能在肿瘤治疗中发挥协同效应。此文就IL-21与部分单克隆抗体联用治疗肿瘤的效果进行综述。

 Interleukin-21 (IL-21) is a typeⅠcytokine made of 4 α helical bundles. IL-21 is highly homologous with IL-2, IL-4 and IL-15, and plays various roles in immunoregulation. Related researches show that IL-2 is closely linked with some tumors. As a potential immunomodulator, IL-21 has promising application prospects in tumor therapy. IL-21 combined with monoclonal antibody has a synergistic effect in tumor therapy. In this paper, the effect of IL-21 combined with monoclonal antibody in tumor therapy is reviewed.