Figure 2.

Main mechanisms by which innate immune cells regulate T-cell responses in HCC. CD8+ T cells and CD4+Th1 cells play antitumoral roles in HCC, whereas Treg cells and Th2 cells play protumoral roles in HCC. Innate immune cells can regulate T-cell responses to further mediate the development of HCC. IDO, indoleamine-2,3-dioxygenase; TAA, tumor-associated antigen; MIP-2, macrophage inflammatory protein 2; G-CSF, granulocyte colony-stimulating factor; DCs, dendritic cells; TAMs, tumor-associated macrophages; TANs, tumor-associated neutrophils; NCR, natural cytotoxicity-triggering receptor; ILC, innate lymphoid cells; MDSCs, myeloid-derived suppressor cells; TGF-β, Transforming growth factor beta; HCC, hepatocellular carcinoma; PD-1, programmed death 1; PD-L1, programmed death ligand-1; Treg, T regulatory cells; CCL, CC chemokine ligand.