In situ injury-induced release of basic-fibroblast growth factor from corneal epithelial cells.
Basic-fibroblast growth factor (b-FGF) binds to heparan sulfate proteoglycan in Bowman's layer of the cornea. The mechanism by which the molecule is deposited in Bowman's layer is the subject of controversy since b-FGF lacks a signal peptide sequence for extracellular secretion. Using immunofluorescence, the authors studied the presence and distribution of b-FGF in the bovine cornea and the conditions under which it could be released and bound to Bowman's layer. The results indicate that corneal epithelium contains b-FGF but that uninjured corneas do not contain detectable levels of b-FGF in Bowman's layer. Injury to the corneal epithelium results in the binding of b-FGF to Bowman's layer. Removal of the intact corneal epithelium without cell injury does not result in the binding of b-FGF to Bowman's layer. These findings suggest that one mechanism for the release of b-FGF from corneal epithelial cells is passive leakage after cell injury with secondary binding to Bowman's layer.
Adamis
A P
AP
Pharmacology Unit, Eye Research Institute, Boston, MA 02114.
Meklir
B
B
Joyce
N C
NC
D000818:Animals; D002417:Cattle; D003315:Cornea / Q000737:chemistry / Q000166:cytology*; D065306:Corneal Injuries; D004847:Epithelial Cells; D004848:Epithelium / Q000737:chemistry; D016222:Fibroblast Growth Factor 2 / Q000032:analysis*; D005455:Fluorescent Antibody Technique; D007150:Immunohistochemistry
D016222:Fibroblast Growth Factor 2