CD47 and neoplasm: Binding of CD47 and SIRPα leads to phosphorylation of immunoreceptor tyrosine-based inhibition motif (ITIM) on SIRPα and recruitment and activation of Src homology phosphatases 1 (SHP-1) and 2 (SHP-2) (mainly SHP-1 in macrophages), both of which inhibit accumulation of myosin-IIA at the phagocytic synapse, and interrupt signaling from tyrosine kinase-dependent receptors like the M-CSF receptor c-fms, thereby inhibits phagocytosis of macrophages (61, 62), anti-body-dependent cellular cytotoxicity (ADCC) mediated by NK cells (63), and neutrophil-mediated killing of tumor cells (64).