Modulation of CD1a and CD14 expression. (A) CD34⁺ cells were cultured for 14 to 70 days with FLT3-L plus TPO with or without SCF. Cells were then cultured for (B) 5 or (C) 12 days with GM-CSF plus TNF or (D) for 2 days with GM-CSF plus IL-4. (E) Cells were also grown for 2 days with GM-CSF plus IL-4, then for 3 days with the latter cytokines plus TNF. Cytokines were renewed after 3 days of culture except for primary cultures. This is the mean of five experiments ± SD.