Fig. 4.

PMX-53 causes degranulation in human mast cells via GPCR. LAD2 mast cells were pretreated with vehicle, GPA-2 (1 μM, 30 min; A), or PTx (100 ng/ml, 16 h; B). Cells were stimulated with 10 nM C5aP and 100 nM PMX-53, and degranulation was determined. In all experiments, LAD2 cells were also stimulated by IgE/anti-IgE as a non-GPCR control. Data are mean ± S.E.M. of n = 3. Statistical significance was determined by one-way ANOVA with Dunnett's post test to compare differences between vehicle and GPA-2 or PTx treatment. *, p < 0.05.