871932.fig.001a
(a)
871932.fig.001b
(b)
871932.fig.001c
(c)
871932.fig.001d
(d)
871932.fig.001e
(e)
871932.fig.001f
(f)
871932.fig.001g
(g)
871932.fig.001h
(h)
871932.fig.001i
(i)
871932.fig.001j
(j)
871932.fig.001k
(k)
871932.fig.001l
(l)
Figure 1: Airway tissue sections stained with BrdU. Histological images (×10) of airway wall sections from airways undergoing repair 6 hours ((a)–(c)), 1 day ((d)–(f)), 3 days ((g)–(i)), and 7 days ((j)–(l)) after physical injury induced by bronchial brush biopsy. The leftmost column depicts the undamaged airway wall opposite the site of injury, the middle column: the transitional zone between that area, and the area directly damaged by the brush biopsy in the rightmost column. No increase in proliferative activity was apparent 6 hours after physical injury ((a)–(c)). By day 1, there was a noticeable increase in the proliferative activity in the epithelium of the transitional zone bordering the lesion (e) as well as in the mucosa and submucosa underlying the area of damage (f). By day 3, there was still evidence of cell proliferation in both the lesion margins (h) as well as in the organising matrix of the damaged wall (i). By day 7, the extent of proliferation had started to decline in both areas ((k), (l)).