Fig. 5.

Location of IdU Label-retaining cells.

Corneal and limbal tissues from adult (C57BL/6) mice exposed to long-term IdU treatment (30 days) followed by washout periods: 0 week, 4 weeks and 10 weeks. (A) Hematoxylin-stained cross-sections of corneal and limbal tissues. IdU visualized by immunostaining (brown). (a, b) No IdU-treatment (negative controls). (c, d) 0-week washout – all cells labelled. (e, f) 4-weeks washout. (g,h) IdU-label undetectable in the corneal epithelium after 10-weeks washout but ~25% of basal limbal epithelial cells retain IdU-label (green arrows). Scale bar = 20 μm. (B) IdU-immunostaining (red) of flat-mounted limbal epithelia after 30 days IdU labelling. TO-PRO3 (blue) nuclear stain. (a) 0-week washout shows IdU label in 100% of the cells. (b) 4-weeks washout. (c) 10-weeks washout period reveals ‘label-retaining cells’ indicated by white arrows. Scale bar = 10 μm. Abbreviations: wk., week; h, hours.