Dose response and kinetics of etheno-ADP-ribosylation of cell-surface proteins by ART2.2-GPI– and ART2.2-Tm–transfected cells. (A) Untransfected, ART2.2-GPI–transfected, and ART2.2-Tm–transfected DC27.10 cells were incubated for 10 minutes in the absence (dashed lines) or presence (solid lines) of 50 μM etheno-NAD (eNAD). Cells were then washed, stained with Alexa488-conjugated mAb 1G4, and subjected to FACS analysis. Numbers indicate mean fluorescence intensity of cells incubated with etheno-NAD. (B) ART2.2-GPI–transfected () or ART2.2-Tm–transfected (□) DC27.10 cells were incubated for 3 minutes in the presence of the indicated concentrations of etheno-NAD. Cells were then subjected to FACS analysis as in panel A. (C) ART2.2-GPI–transfected () or ART2.2-Tm–transfected (□) DC27.10 cells were incubated for the indicated times in the presence of 1 μM etheno-NAD. Cells were then subjected to FACS analysis as in panel A. Results are representative of 3 independent experiments.