Synergistic effects of hyaluronan and fibronectin on epithelial migration in rabbit cornea in vitro.
OBJECTIVE
We investigated the interactions of hyaluronan with extracellular matrix proteins (fibronectin, laminin, and type IV collagen) on corneal epithelial migration by using an organ-culture system of rabbit corneas.


METHODS
Rabbit corneal blocks were cultured in the absence or presence of various reagents for a total of 20 h. The corneal blocks were then fixed, dehydrated, embedded in paraffin, and stained by hematoxylineosin, and the length of the path of epithelial migration was measured.


RESULTS
The addition of hyaluronan, fibronectin, or type IV collagen alone stimulated epithelial migration in a dose-dependent manner, but laminin did not. When corneal blocks were pretreated with extracellular matrix proteins (fibronectin, laminin, or type IV collagen) for 5 h and then were cultured for 15 h with hyaluronan, only pretreatment with fibronectin demonstrated a synergistic effect with hyaluronan on corneal epithelial migration. In contrast, when corneal blocks were pretreated with hyaluronan for 5 h and then cultured for 15 h with extracellular matrix proteins, the additive effects of hyaluronan with fibronectin or hyaluronan with type IV collagen were observed. The synergistic effects of hyaluronan and fibronectin on corneal epithelial migration were partially inhibited by the addition of antiserum against fibronectin. In contrast, the addition of antiserum against fibronectin receptor completely inhibited the synergistic effects of hyaluronan and fibronectin on epithelial migration.


CONCLUSIONS
These results suggest that hyaluronan and fibronectin have a synergistic effect, with fibronectin pretreatment augmenting hyaluronan-stimulated corneal epithelial migration.
Nakamura
M
M
Department of Ophthalmology, Yamaguchi University School of Medicine, Ube City, Japan.
Nishida
T
T
D000818:Animals; D002465:Cell Movement / Q000187:drug effects; D003094:Collagen / Q000494:pharmacology; D046508:Culture Techniques; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D019573:Epithelium, Corneal / Q000166:cytology / Q000187:drug effects* / Q000502:physiology*; D005353:Fibronectins / Q000276:immunology / Q000494:pharmacology*; D006820:Hyaluronic Acid / Q000494:pharmacology*; D007106:Immune Sera / Q000494:pharmacology; D007797:Laminin / Q000494:pharmacology; D009994:Osmolar Concentration; D011817:Rabbits; D017469:Receptors, Fibronectin / Q000276:immunology
D005353:Fibronectins; D007106:Immune Sera; D007797:Laminin; D017469:Receptors, Fibronectin; D006820:Hyaluronic Acid; D003094:Collagen