GP1a treatment reduces PGE2 induced ERK phosphorylation. (A) DCs were treated with PGE2 with or without different concentrations of GP1a for 20 minutes. Cells were fixed, permeabilized, stained intracellular with phospho-ERK antibody, and analyzed by FACS. (B) DCs were treated with PGE2 with or without GP1a for various time periods. Cells were lysed and analyzed for phosphorylation of ERK by Western blot. Densitometric analyses are plotted in graphs normalizing phospho-ERK to total ERK. Data are representative of 2 (B) and 3 (A) independent experiments.