CD47 and neoplasm: Recently, two glycosylation sites on CD47 in the interface of CD47 with SIRPα were identified, and several SIRPα mutants with different binding ability to CD47 expressing on human RBCs and tumor cells were reported, which makes it possible to discover antibodies specifically binding to tumors cells with no cross-reactivity with CD47 on RBCs 15, 16.