Figure 3.

Acute PG/VG exposure increases intracellular MUC5AC levels in cultured human bronchial epithelia. (A) Typical hematoxylin and eosin and Alcian blue–periodic acid–Schiff staining of fixed bronchial cultures after acute air versus 36.8% PG/VG/nicotine exposures. (B) Representative confocal microscopy images of fixed cultures stained with Hoechst (nuclei; blue), MUC5AC (green), and cilia (α-tubulin; white). (C) Mean log₂ fold changes in MUC5AC fluorescence after exposure to various doses of PG/VG (shaded columns) or PG/VG + nicotine (solid columns). *P < 0.05, different air exposure (i.e., 0% PG/VG). Data shown as means ± SEM. AB/PAS = Alcian blue–periodic acid–Schiff; H&E = hematoxylin and eosin; MUC5AC = mucin 5AC; PG/VG = propylene glycol/vegetable glycerin.