title: Spatial distribution of keratan sulfate in the rabbit cornea following photorefractive keratectomy.
abstract: OBJECTIVE
  To examine the keratan sulfate content of the stroma and to assess its correlation with the healing process (epithelialization and keratocyte density) after photorefractive keratectomy (PRK).
  
  
  METHODS
  Using an Aesculap Meditec MEL 70(G-scan) excimer laser, -6.0 diopters (6.0-mm diameter, 82 microm photoablation depth), PRK was carried out on the right eye of 32 New Zealand pigmented rabbits. After enucleation (at days 1, 4, 7, 14, and 28 and months 2, 3, and 7; sub-groups of 4 animals), fluorescent immunohistochemistry was performed on sections from the central comea using monoclonal mouse anti-keratan-sulfate antibody, immunohistochemistry with proliferative cell nuclear antigen antibody, and hematoxylin-eosin histology. The left, untreated eyes served as controls. Cellular morphology and spatial distribution of keratan sulfate were recorded, stromal thickness measured, and keratocyte density calculated.
  
  
  RESULTS
  Keratan sulfate was found on the surface of migrating epithelial cells in the early stage (from days 1 to 7). In the stroma, three phases were noted. (Phase 1) Day 1 to 14, intense granular fluorescence appeared in the anterior stroma with hypocellularity. (Phase 2) Month 1 to 2, newly synthesized lamellar keratan sulfate restored the repopulating anterior stroma. Endothelial cells became keratan sulfate positive, while in the posterior stroma, lamellar-form keratan sulfate increased from week 1 and peaked at month 1 (100% increase). (Phase 3) Month 2 to 7, remodeling and deposition of keratan sulfate was noted, which was produced in phase 2.
  
  
  CONCLUSIONS
  Keratan sulfate was found in the epithelium, stroma, and endothelium. By controlling the interlamellar spacing, keratan sulfate plays a role in postoperative edema, remodeling of the corneal stroma, and simultaneous regulation of inflammation after PRK.
authors.affiliation: Department of Ophthalmology, Semmelweis University, Budapest, Hungary. remi@szem1.sote.hu
authors.forename: Miklós D
authors.initials: MD
authors.lastname: Resch
authors.forename: Zoltán Z
authors.initials: ZZ
authors.lastname: Nagy
authors.forename: Nóra
authors.initials: N
authors.lastname: Szentmáry
authors.forename: Miklós
authors.initials: M
authors.lastname: Máthé
authors.forename: Ilona
authors.initials: I
authors.lastname: Kovalszky
authors.forename: Ildikó
authors.initials: I
authors.lastname: Süveges
mesh_terms: D000818:Animals; D003315:Cornea / Q000378:metabolism* / Q000601:surgery*; D019084:Fluorescent Antibody Technique, Indirect; D007124:Immunoenzyme Techniques; D007632:Keratan Sulfate / Q000378:metabolism*; D054018:Lasers, Excimer; D018903:Photorefractive Keratectomy; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D011817:Rabbits
chemical_list: D018809:Proliferating Cell Nuclear Antigen; D007632:Keratan Sulfate