At 1 and 3 days after photokeratectomy, hypertrophied and
irregular epithelium was forming over thinned stroma with no
microscopically appreciable difference in re-epithelialization between
control and Plg
−/− mice. Inflammatory cells
were seen at day 1 after photokeratectomy, in both control and
Plg
−/− mice but inflammatory cells were rarely
seen at days 3, 7, or 21 in either group of mice. Although fibrin was
neither present in untreated eyes from control or
Plg
−/− mice nor in eyes taken from mice killed
within 1 hour of photokeratectomy, fibrin deposits were easily detected
at 1 and 3 days after photokeratectomy. Fibrin was deposited
predominantly subepithelially and diffusely throughout the anterior
stroma
(Fig. 4) . At day 7 after photokeratectomy, although
normalization of the epithelium was occurring in mice of both
genotypes, control mice had only subtle fibrin deposits in some corneas
(2/10 eyes), whereas corneas of Plg
−/− mice
contained moderate to intense fibrin in the stroma and anterior chamber
(7/10 eyes;
Fig. 4 ). At day 21, control eyes had no evidence of stromal
or anterior chamber fibrin. However, stromal fibrin was detected in 14
of 19 (74%) Plg
−/− eyes in a diffuse pattern
throughout both the anterior and posterior stroma (
Fig. 4 ; control
versus Plg
−/−:
P < 0.0001).
Anterior chamber fibrin was detected in 9 of 19 (47%)
Plg
−/− eyes in the form of pupillary,
retrocorneal, and transchamber membranes; anterior synechiae; and
iridocorneal adhesions (
Fig. 4H ; control versus
Plg
−/−:
P = 0.013). Mild
corneal edema was present in 8 of 19 (42%)
Plg
−/− eyes and in 0 of 22 control eyes
(control versus Plg
−/−:
P =
0.003) at day 21. Early scar formation was occasionally seen in
Plg
−/− eyes
(Fig. 4G) .