Abstract
Purpose :
Defining the extent of initial injury has proven to be a useful basis for determining the usefulness of ocular regenerative modalities. However, a quantitative analysis of the extent of different chemical and physical injuries has not been demonstrated. In the following studies we characterized the clinical and histopathological changes of the cornea, limbus and conjunctiva following exposure to different chemical and mechanical injuries in the mouse model.
Methods :
Five groups of mice received the following injuries: 2min-Algerbrush, 1min-Algerbrush with thermal, Sodium Hydroxide (NaOH) 0.5 N for 30sec, Absolute Ethanol (E) for 30sec and 1 min. Slit lamp and optical coherence tomography evaluation on day 0, 2, 4, 6, 8, 10 and 14, were done. The corneal opacity, corneal new vessel formation and anterior segment reaction were evaluated. The origin of the corneal epithelial cells was determined by anti CK3 and CK13 Abs. The amount of corneal fibrosis and limbal stem cell activities were revealed by anti aSMA and Anti ABCB5 Abs. The morphological changes in orbital lacrimal gland after different injury induction were evaluated. Two-tailed student paired T-test and ANOVA test were used to compare the result between different groups.
Results :
Based on macroscopic scores, the order of corneal opacity on day 14 was Algerbrush (2+) < E 30sec (2.33+) < Algerbrush with Thermal (2.9+) < E 60sec (3.25+) < NaOH 30sec (4+). Histopathologic evaluation revealed the highest inflammatory reaction, goblet cell expression and stromal cell infiltration in the NaOH injury and the least inflammation and goblet cell expression belonged E 30sec. E 30 and 60sec injured eyes showed the highest fibrosis marker and the least number of new vessel formation. All injured corneas expressed CK13 with no CK3. ABCB5 was expressed the most after NaOH and E 60sec injury.
Lacrimal gland reacted to all injuries by dilation of the ductal tissue and changing the morphology of the acinar cells that was more prominent in NaOH injury.
Conclusions :
Overall, these data indicate that ocular irritation because of NaOH induces the most severe inflammation. E injury is more suitable for fibrosis induction. Algerbrush injury recruits the least inflammatory cells and is more suitable for epithelial debridement studies.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.