Correlation between epithelial ingrowth and basement membrane remodeling in human corneas after laser-assisted in situ keratomileusis.
OBJECTIVE
To further investigate the hypothesis that epithelial ingrowth in human corneas after laser-assisted in situ keratomileusis (LASIK) correlates with basement membrane remodeling, as suggested by the presence of matrix metalloproteinase 9 around epithelial cells in the lamellar scar.


METHODS
Immunohistochemical analysis and transmission electron microscopy were applied to human postmortem corneas with post-LASIK epithelial ingrowth.


RESULTS
Epithelial ingrowth into the flap margin was observed in 8 of 18 corneas (44%). Matrix metalloproteinase 9 immunolocalized around ingrown epithelium in 6 of these 8 corneas (75%). There was a positive correlation between the presence of matrix metalloproteinase 9 at the wound margin and discontinuities in the basement membrane, as determined by laminin and beta(4) integrin immunofluorescence. Transforming growth factor beta2 was present into the stroma of some corneas with epithelial ingrowth and interrupted basement membrane, suggesting some degree of epithelial-stromal interaction. Transmission electron microscopy confirmed large areas of remodeled basement membrane along ingrown epithelial cells.


CONCLUSIONS
The neo-basement membrane components underlying the ingrown cells in human corneas with epithelial ingrowth after LASIK appear to be partially disassembled. Epithelial-stromal interaction over time may be related to prolonged wound healing remodeling, which calls into question the stability of the flap.
Fournié
Pierre R
PR
Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida, USA. fournie.p@chu-toulouse.fr
Gordon
Gabriel M
GM
Dawson
Daniel G
DG
Malecaze
François J
FJ
Edelhauser
Henry F
HF
Fini
M Elizabeth
ME
D000328:Adult; D001485:Basement Membrane / Q000502:physiology*; D016764:Cell Polarity; D003319:Corneal Stroma / Q000473:pathology*; D019573:Epithelium, Corneal / Q000473:pathology*; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D039663:Integrin beta4 / Q000378:metabolism; D020731:Keratomileusis, Laser In Situ; D007797:Laminin / Q000378:metabolism; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism; D046529:Microscopy, Electron, Transmission; D008875:Middle Aged; D013524:Surgical Flaps / Q000473:pathology*; D053781:Transforming Growth Factor beta2 / Q000378:metabolism
D039663:Integrin beta4; D007797:Laminin; D053781:Transforming Growth Factor beta2; D020780:Matrix Metalloproteinase 9