SIRPA and cancer: Similar to Fig. 4K, we observed M1 NextA treated macrophages exhibited the highest phagocytosis when CD47 was blocked, whereas blocking SIRPα on macrophages did not enhance phagocytosis to the extent we observed with M1 NextA and anti-CD47, thus indicating that blocking CD47 on cancer cells is more effective than blocking SIRPα on macrophages to modulate phagocytosis of melanoma cells by macrophages.