Abstract
Purpose :
To determine if the corneal haze which is found at the wound periphery is different from the haze found in the center of the cornea.
Methods :
All of the animals used herein were treated in a manner consistent with the ARVO Statement for the Use of Animals in Ophthalmic and Vision Research. New Zealand White Rabbits’ corneas from both eyes were ablated using an excimer laser to simulate a PRK procedure. Following induction of the PTK model, the wounds were allowed to heal and were periodically observed via macrophotography. After 14 days, the corneas were harvested, fixed, and prepared for whole tissue staining with a directly labeled monoclonal antibody to α-SMA. The stained and mounted cornea was then imaged with a confocal fluorescent microscope and a mosaic encompassing the whole injury was made in ImageJ.
Results :
The distribution of α-SMA at the periphery was consistent with the level of haze observed and had a highly networked contractile-like morphology. However, the central cornea had less α-SMA staining and the cellular morphology was more long and spindle-like and almost had a vascular appearance despite the lack of angiogenesis observed in the cornea.
Conclusions :
The density of α-SMA staining correlated with the intensity of haze at the periphery, but not the center of the cornea. The morphology of the staining, when paired with previous observations of the two separate regions initiating and developing haze separately, suggests that more than just on cellular biological process is occurring and generating light reflection. The evidence supports a myofibroblast-like process at the periphery and possibly de novo vasculogenesis in the center of the cornea. α-SMA is a marker for both myofibroblasts and vascular cells as well, and these data suggest that anti-haze therapies may need to be catered to two differing processes which both contribute to haze formation.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.