FIGURE 4.

CMP enhances the structure of healing corneal epithelium. Representative differential interference contrast images of histological sections with hematoxylin and eosin staining through regenerated epithelium (A, B) and the proliferative edge (C) 24 h following induced corneal injury. While vehicle-treated eyes demonstrated frequent gaps beneath the epithelium (A, left; dashed line), treatment with CMP enhanced adherence of the basal layer (brackets) to the underlying anterior stromal surface (arrows) for both 25 (A, right) and 250 nM (B, at higher magnification) concentrations of CMP. At the proliferative edge of the wound (C), compared to a vehicle, CMP increases the number of new epithelial cells adhering to the corneal stroma (circles). (D) Length of contiguous segments of adherence between basal epithelium and underlying stromal layer calculated from random samples of histological sections through cornea 24 h following epithelial removal (n = 6–11 each). Compared to naïve eyes, vehicle-treated corneas demonstrated a 36% reduction in the average length of adherent surface (#: p < 0.001). Treatment with CMP significantly increased adherence compared to a vehicle (*: p ≤ 0.02), comparable to adherence in naïve corneas (p ≥ 0.37). (E) The number of epithelial cell nuclei in basal layer quantified in random samples (n = 29–100 each). Treatment with CMP increased the number of cells per sample significantly compared to a vehicle (*: p ≤ 0.04); the number of cells following 250 nM CMP treatment exceeded naïve (#: p = 0.008) (F). Deviation in the number of epithelial nuclei in each random sample from (A) compared to the mean number for each cohort. The vehicle group was significantly more variable than naïve (#: p < 0.001); treatment with 250 nM CMP reduced deviation by 54% compared to a vehicle (*: p < 0.001) but remained higher than naïve (p = 0.04).