FIG. 1.

Assessment of preparative LMP1 immunoprecipitation from C15 rafts using the OT21C antibody. Samples of C15 rafts corresponding to 60 μg of protein were submitted to immunoprecipitation using 15 μg of purified OT21C or irrelevant mouse IgG1 covalently bound to 1.5 × 10⁸ magnetic beads. Parallel blots were stained with anti-LMP1 (CS1-4), anti-TRAF3, and anti-Lyn. The last blot was restained with β-actin antibodies. Input, raft-derived proteins saved prior to the immunoprecipitation step (5 μg, LMP1; 10 μg, TRAF3, Lyn, and β-actin); mIgG1, one-third of the eluted proteins recovered from control immunoprecipitation (irrelevant mouse IgG1); OT21C, one-third of the eluted proteins recovered from LMP1 immunoprecipitation. Using the above-mentioned ratios of magnetic beads, antibodies, and raft proteins, about 100% of LMP1 and 50% of TRAF3 were recovered by immunoprecipitation with OT21C. All the experiments depicted in this and subsequent figures were performed at least twice.