Effects of retinoids on CD11b expression on HL-60 (A, B, C, and D) and NB4 cells (E and F). Cells were cultured for 48 hours with 10^-12 to 10^-8 mol/L ATRA (A, C, and D in HL-60, E and F in NB4 cells), Retinoid A (B), Retinoid B (B), Retinoid C (B), Retinoid D (C and E), or Retinoid E (D and F), or a combination of equal molar concentrations of Retinoids D or E with ATRA (C, E and D, F, respectively) and cells then were analyzed by FACScan for expression of CD11b. This figure shows representative findings of three independent experiments, each of which had similar results.