Sustained phosphorylation of ERK in HRF/TCTP-R basophils. (A) Representative anti–phospho-ERK blots from an HRF/TCTP-R (top row) and HRF/TCTP-NR (bottom row) donor. Basophils were stimulated with 0.3 μg/mL anti-IgE for the times noted. There was no phosphorylation in the 1-minute blank (1′bl) nor in the 60-minute blank (60′bl). The standard (Std) is 5 μL of an RBL standard sensitized with DNP-specific IgE and stimulated with DNP₃₅ BSA antigen. Vertical lines have been inserted to indicate a repositioned gel lane. (B) Summary of kinetics of ERK phosphorylation stimulated with anti-IgE in HRF/TCTP-R donors (●; n = 4) and HRF/TCTP-NR donors (□; n = 3). The blots were scanned and values normalized as described in “Methods.” The standard error is represented by the error bars.