Figure 2.
CD47 functions in the tumor microenvironment. A) CD47 on tumor cells induces inhibitory SIRPα signaling that prevents macrophage phagocytosis and antigen presentation. Thrombospondin-1 induces CD47 signaling in CD8 T cells and NK cells that inhibits lytic tumor cell killing [15, 113]. B) CD47 antibodies that block SIRPα binding relieve the inhibitory signal in macrophages and antigen-presenting cells, enabling pro-phagocytic signals from tumor-secreted calreticulin or tumor-specific antibodies to activate ADCP and ADCC. C) Bispecific CD47 antibodies enhance selective blocking of CD47 on tumor cells and induce ADCP and/orADCC.