ART2.2-GPI but not ART2.2-Tm is released from cells by exogenous PI-PLC treatment, whereas ART2.2-Tm but not ART2.2-GPI is released from cells by treatment with TX-100 at 4°C. (A) DC27.10 cells stably transfected with ART2.2-GPI or ART2.2-Tm were incubated for 60 minutes at 37°C in the absence (solid lines) or presence (dashed lines) of PI-PLC. Cells were then washed and stained for cell-surface expression of GM1, ART2.2, or LFA-1 before FACS analysis. Number indicates the percentage reduction of the mean fluorescence intensity of PI-PLC treated compared with untreated ART2.2-GPI transfectants. (B) DC27.10 cells stably transfected with ART2.2-GPI or ART2.2-Tm were stained for cell-surface expression of GM1, ART2.2, or LFA1. Cells were then washed and incubated for 10 minutes at 4°C with or without 1% TX-100 before fixation and FACS analysis. Numbers indicate percentage reduction of mean fluorescence intensity of TX-100–treated compared with untreated cells. (C) DC27.10 cells stably transfected with ART2.2-GPI or ART2.2-Tm were stained for cell surface expression of GM1 and ART2. Cells were then washed and incubated for 10 minutes at 4°C with (+) or without (-) 1% TX-100 before fixation and confocal microscopic analysis. Results are representative of 3 independent experiments.