Kallistatin protein levels in nondiabetic and diabetic corneas. A: Representative immunostained images of kallistatin (green) and DAPI (blue) in the corneas from donors with DM and NDM donors (n = 6). Epi, epithelium; Str, stroma. B: Representative immunostained images of kallistatin (green) and DAPI (blue) in the corneas from STZ-induced DM rats (3 months of diabetes) and NDM controls (n = 3). Representative Western blots for kallistatin and densitometry quantification in the corneas from Akita mice (n = 3) (C), STZ-induced DM mice (n = 5) (D), and db/db mice (n = 3) (E), and their respective NDM controls. All values are mean ± SEM. *P < 0.05, **P < 0.01.