摘要
Hepatocellular carcinoma(HCC)is the fourth leading cause of cancer-related deaths worldwide(1).Resident immune cell populations within the liver,which is considered the largest immune organ,increase the pathological complexity of HCC(2).Innate lymphoid cells(ILCs),recently identified leukocytes,are a family of innate immune cells with similar characters to T lymphocytes.ILCs largely exist in intestinal mucosal tissue and regulate intestinal inflammation,mucosal defense,and tissue repair in gut disease processes(3).Unlike T cells,ILCs lack antigen-specific receptors;therefore,they cannot directly mediate antigen-specific responses(4).However,they can be activated by cytokines and/or natural cytotoxic receptors(such as NKp44)(5).ILCs are a highly heterogeneous cell population with high plasticity.Based on the expression of transcription factors and the production of different cytokines,ILCs can be divided into ILC1,ILC2,and ILC3,which are counterparts of the three main helper T cell subsets(Th1,Th2,and Th17)(6).Although ILCs can be detected in various tumor types,their specific contribution to tumor immunity is yet to be thoroughly elucidated.
