(A) Vimentin contents are increased in early Smo cultures, and up to mid-term in COPD ALI-AE, with this increase vanishing in long-term cultures. (B) Illustrative gels from NS and very severe COPD-derived AE cultured at the ALI from early up to long-term, illustrating the vimentin increased contents up to mid-term in COPD. (C) Increased fibronectin release disappears in mid-term cultures from Smo and mild-to-moderate COPD patients, whereas it persists up to later (7 wk) in (very) severe COPD AE. (D) Increased mRNA levels of SNAI1, SNAI2, TWIST1, and ZEB globally disappear in mid-term cultures from Smo and COPD patients, with punctual persistence of SNAI2 increase in long-term Smo ALI-AE. *, ** indicate P-values of less than 0.05 and 0.01, respectively. Bars indicate median ± interquartile range. $, £, and § highlight significant decreases in Smo, COPD1-2, and COPD3-4 patients, respectively, as compared with NS. AE, airway epithelium; ALI, air-liquid interface; COPD, chronic obstructive pulmonary disease; GAPDH, glyceraldehyde-3-phosphate dehydrogenase; NS, non-smokers; ns, not significant; Smo, smokers; w, weeks.