Inflammation and airspace enlargement after 16 weeks cessation. A BAL total cells, mononuclear cells, and neutrophils at 16 weeks post 24 week smoke exposure. ***p < 0.001 by one-way ANOVA with Tukey post-hoc. B Representative, H&E stained, whole slice histology from a control (left), cessation (middle), and continuing smokers at the +16 week time-point. C Average airspace area distributions by logarithmic bins of airspace, describing whole slice histology. D Average airspaces per unit area and E average area to perimeter ratio produced from analysis of whole slice histology. *p < 0.05, **p < 0.01, ***p < 0.001 by one-way ANOVA with Tukey post-hoc.