Enhanced RAR activation in GM-CSF–treated 32D cells.

Shown are FACS-generated histograms of Mac-1 (Cd11b) and Gr-1 expression in (A) 32D cells cultured in IL-3 alone and (B) 32D cells cultured in GM-CSF alone (6 days). (C) The 32D cells cultured in either IL-3 or GM-CSF were transfected with the RXR/RAR-responsive RARE tk-LUC reporter, cultured for 5 hours in the presence or absence of the indicated concentration of ATRA, followed by determination of luciferase activity. The fold activation represents the ratio of uninduced versus induced luciferase activity for the different concentrations of ATRA.