Canonical Notch signaling mediates Dll4-inhibition of MK differentiation. (A-B) Human cord blood CD34⁺ cells were plated onto Dll4Fc-coated plates in the presence of 10μM DAPT or mock (DMSO) control. FACS analyses for CD41a and CD42b markers of cultured cells were performed after 10 days of cultures. (A) FACS analyses for CD41a and CD42b markers of 1 representative experiment. (B) Histogram representation of flow cytometric results presented in panel A. Mean ± SEM from 3 independent flow cytometric analyses after 10 days of culture is shown. (C) Human cord blood CD34⁺ cells were transduced with retrovirus encoding either DN-MAML1 or MIG-empty vector (the transduction rate was close to 30% for both retroviral vectors), and 2 days later, plated onto control and Dll4Fc-coated plates. FACS analyses of cultured cells were performed after 7 days of cultures onto Dll4Fc. Flow cytometric analysis of CD41a and CD42b markers in GFP⁺ cells from control and Dll4Fc cultures (1 representative experiment). (D) Histogram representation of flow cytometric results presented in panel C. Mean ± SEM from 5 independent flow cytometric analyses after 10 days of culture.