Increase in percent alcian blue positive cells (goblet cell metaplasia) in gp91phox-/- and gp91phox-MMP12 double knockout (DKO) post-OVA compared to wildtype (WT) post-OVA. Metaplastic goblet cells were counted as the blue cells stained positive by alcian blue. Percent metaplastic goblet cells is calculated from the total number of cells counted around each airway. Abbreviations used are: WT = wildtype, NOX = gp91phox-/-, DKO = gp91phox-MMP12 double knockout, WA = WT+alum, WO = WT+OVA, NOXA = gp91phox-/-+alum, NOXO = gp91phox-/-+OVA, DKOA = gp91phox-MMP12 double knockout+alum, DKOO = gp91phox-MMP12 double knockout+OVA. The results shown are pooled from 3 independent experiments. Counts were taken and averaged over 10 high power fields. Slides were counted on a Spencer AO light microscope at 40 × magnification. Results are expressed as percent ± SEM. n = 5 animals/group. * denotes p value < 0.01 compared to post-OVA wildtype values.