The Modulating Function of Osteopontin and Osteopontin Monoclonal Antibody in Human Tenon's Fibroblasts

Abstract

Objective: To assess the modulating function of osteopontin (OPN) on human Tenon's fibroblasts (HTFs). Methods: With the intervention of OPN in different concentrations (0, 0.05 μmol/L, 0.5 μmol/L, and 5 μmol/L), the proliferation rate of HTFs was measured by 3-(4,5-dimethylthiazol-2-Yl)-2,5-diphenyltetrazolium bromide (MTT), and the motility was surveyed by the cell scratch method. Real-time polymerase chain reaction (PCR) was applied to measure the mRNA of vascular endothelial growth factor (VEGF) and transforming growth factor β (TGF-β) in HTFs in the presence of different concentration of OPN. Western blot was used to measure the collagen-I levels. Data were analyzed using ANOVA. Results: OPN induced the proliferation of HTFs as indicated by MTT and enhanced the motility of HTFs as shown by the cell scratch method. The effects were concentration dependent (F=174.5, 297.1, P<0.01). In the presence of anti-OPN 1A12 (5 µmol/L OPN+20 µg/ml 1A12), the effects of OPN on HTFs were inhibited. None of the concentrations of OPN affected mRNA levels of VEGF and TGF-β mRNA. OPN augmented HTF expression of collagen-I protein in a concentration-dependent manner (F=30.2, P<0.01). Conclusions: The enhancement of HTF proliferation, motility, and collagen-I expression OPN was concentration dependent. Incubation with the monoclonal OPN antibody 1A12 inhibited the effects of OPN on the HTFs. Key words: osteopontin; human Tenon's fibroblasts; mechanism