Figure 4

Effect of guaifenesin (GGE), N -acetylcysteine (NAC) or ambroxol (Amb) on secretion of MUC5AC. The MUC5AC concentrations in two washes of the apical surfaces of quadruplicate cultures for each condition were analysed by ELISA. All samples and standards included 0.025 mM dithiothreitol (DTT), resulting from the 1:4 dilution of the samples collected in 0.1 mM DTT. The results from the two washes were combined and are reported as the concentration relative to the standard curve, generated from dilutions of a pooled sample of washes collected from other samples. Separate cultures were analysed at the three time points. *, ** and *** indicate p < 0.05, 0.01 and 0.005, respectively, vs. IL-13-only group (ANOVA with Dunnett’s post-test). Horizontal lines above the groups indicate significant trend tests (all include the IL-13-only, zero drug, condition as indicated by the short line over this bar at the same height).