Fig. 5.
Vitamin C inhibits Stat5 transcriptional activation mediated by GM-CSF.
(A) 293T cells transfected with either the reporter construct p8xGAS-luc or cotransfected with plasmids containing the cDNAs for αGMR and/or βGMR were incubated for 5 hours with 1 nM GM-CSF (closed bars) or buffer (open bars), and luciferase activity was measured in cell lysates. (B) 293T cells cotransfected with plasmids encoding the cDNAs for αGMR, βGMR, and the reporter construct p8xGAS-luc were incubated for 30 minutes with increasing concentrations of DHA. Transfectants were incubated for 5 hours with 1 nM GM-CSF (closed bars) or no additions (open bars), and luciferase activity was measured in cell lysates. Bars represent the average values of triplicate determinations ± SD.