Persistent adhesion of corneal epithelial tissue on synthetic lenticules in vivo.
OBJECTIVE
In intact cornea, firm anchorage of the epithelium to its underlying stroma is provided by a system of adhesive structures, which include the epithelial basement membrane, adhesion complexes and associated alpha6beta4 integrin receptors. In the present study we sought to determine whether the sustained epithelialization of synthetic lenticules observed in vivo involved the formation of adhesive structures at the epithelial-lenticule interface similar to those present in intact tissue.


METHODS
Collagen I-coated microporous polycarbonate membranes were implanted in the anterior stroma of adult cats. Successfully epithelialized lenticules were maintained on eye for 9-12 weeks, after which time the epithelial-lenticule interface was examined for evidence of adhesive structures using immunohistochemistry and electron microscopy.


RESULTS
Immunohistochemistry identified laminin, hemidesmosomal plaque, collagen VII and alpha6 integrin at the tissue lenticule interface. Ultrastructural examination showed evidence of assembly of these components into a basement membrane and adhesion complexes.


CONCLUSIONS
The formation of these adhesive structures is likely to have contributed to the sustained epithelialization observed clinically on the collagen-coated synthetic lenticules.
Cooperative Research Centre for Eye Research and Technology, University of New South Wales, North Ryde, Australia. margaret.evans@molsci.csiro.au
M D
MD
Evans
R Z
RZ
Xie
S D
SD
Tout
J G
JG
Steele
D F
DF
Sweeney
D000818:Animals; D015703:Antigens, CD / Q000378:metabolism; D001485:Basement Membrane / Q000378:metabolism / Q000648:ultrastructure; D002415:Cats; D002448:Cell Adhesion; D003094:Collagen / Q000378:metabolism; D003319:Corneal Stroma / Q000601:surgery; D003896:Desmosomes / Q000378:metabolism / Q000648:ultrastructure; D019573:Epithelium, Corneal / Q000378:metabolism* / Q000648:ultrastructure; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D039503:Integrin alpha6; D007797:Laminin / Q000378:metabolism; D008297:Male; D008567:Membranes, Artificial; D011076:Polycarboxylate Cement; D019736:Prostheses and Implants
D015703:Antigens, CD; D039503:Integrin alpha6; D007797:Laminin; D008567:Membranes, Artificial; D011076:Polycarboxylate Cement; C005506:polycarbonate; D003094:Collagen