Consistently, knockdown of the transcription factor p53 in MDMs reduced the expression of p21 and significantly impaired the phagocytosis of MOLT4 cells without affecting MDM viability (Supplementary Fig. 5a–c), suggesting that the spontaneous phagocytosis of leukemia cells is under the control of p53-dependent p21 expression. Here, TP53 is linked to leukemia.