Figure 4.

PG e-cig aerosols do not affect MUC5AC and MUC5B production in HBECs in vitro. A: representative confocal image stacks of MUC5AC and MUC5B expression and Hoechst (nuclei) stain in HBECs exposed to air or PG e-cig aerosols for 7 days. Scale bar, 100 µm. B: quantification of MUC5AC and MUC5B expression expressed as a ratio of surface area labeling of MUC5AC/Hoechst and MUC5B/Hoechst, respectively. MUC5AC/MUC5B ratio represents the ratio of MUC5AC surface area labeling to MUC5B surface area labeling for each individual image. n = 72 images from 12 lungs. Data are presented as means ± SE. ns = not significant. Data were analyzed using a mixed-effects model. HBECs, human bronchial epithelial cells; PG, propylene glycol.