Migration of cultured bovine trabecular meshwork cells to aqueous humor and constituents.

PURPOSE To investigate the migration of cultured bovine trabecular meshwork cells to aqueous humor and some of its constituents, and to compare the migration of normally proliferating and growth-arrested cells. METHODS Cellular migration was evaluated in 48-well microchemoattraction chambers, and the chemoattractants used were bovine aqueous humor, glycoproteins, and growth factors. RESULTS The meshwork cells responded well to bovine aqueous humor, and antibody neutralization experiments showed that fibronectin accounted for approximately 40% of aqueous chemoattraction. The glycoproteins laminin, thrombospondin, and transferrin elicited only modest migratory activity. Platelet-derived growth factor was the most powerful chemoattractant of the growth factors tested, and the others produced moderate migratory effects. Basic fibroblast growth factor was not chemoattractive on its own but stimulated migration when combined with heparin. Growth-arrested cells showed less migration to a standardized chemoattractive stimulus than did proliferating meshwork cells. CONCLUSIONS For the first time, aqueous humor was shown to act as a migratory stimulus for meshwork cells in vitro. The major attractant is fibronectin; the remaining active constituents must still be identified.