Fig. 5.
Association of Lyn with FcαR is sensitive to treatment with PP1. THP-1 cells (1 × 107/sample) were incubated at 37°C for 30 minutes in RPMI 1640 cell culture medium only (lanes 1, 4, and 5) and cell culture medium containing 10 μmol/L of PP1 (lanes 2 and 6) or 100 μmol/L of PP1 (lanes 3 and 7). Subsequently, cells were activated at 37°C for 5 minutes with 2.5 mg of NC particles adsorbed with huIgA (lanes 1 through 3), huIgG (lanes 5 through 7), or BSA only (lane 4). Immunoprecipitation, separation of precipitated proteins by 8% to 12% SDS-PAGE, and antiphosphotyrosine immunoblot analysis of isolated proteins were performed as described in Materials and Methods (A). Reprobing of the same immunoblot with Lyn-specific antibody (B).
