Figure 1.

Role of hypoxia-induced VEGF in mediating immune tolerance. Diverse effects of hypoxia-induced VEGF on different components of the immune system (TAM, MDSC, DC, CTL, and T reg). In general, hypoxia-induced VEGF pool in tumor microenvironment (VEGF secreted by hypoxic tumor cells, TAM, MDSC, DC, and T reg) amplifies the activity of TAM, MDSC, and T reg while suppressing the function of CTL and delaying the maturation of DC cells. TAM, tumor-associated macrophages; MDSC, myeloid derived suppressor cells; DC, dendritic cells; CTL, cytotoxic T-lymphocyte; T reg, T regulatory cells.