MOS and leukemia: To evaluate the impact of the p21-SIRPα axis on the phagocytosis of leukemia cells, MOLT4 cells stably expressing the fluorescent mCherry reporter gene (mCherry+MOLT4 cells) were cocultured with MDMs generated from genetically engineered human Mos transduced with an empty lentiviral vector (Co.TD-Mos), a CDKN1A-expressing lentiviral vector (p21TD-Mos), a SIRPα-expressing (SIRPαTD-Mos) lentiviral vector or a combination of the lentiviral vectors (p21 + SIRPαTD-Mos).