Inhibitor of FAK Blocks Activation of Corneal Fibroblasts Induced by TGFß

Abstract

Abstract: : Purpose:To determin whether inhibitor of focal adhesion kinase (FAK) can block activation of corneal fibroblasts induced by transforming factorß( TGF ß ), in terms of proliferation, collagen synthesis, and contraction. Methods: Human corneal fibroblasts (HCFs) obtained from eye bank eye were cultured. Then cultured HCFs were exposed to PP2 (inhibitor of FAK), PP3 (inactive analog of PP2), PP2 and TGF ß2, or PP3 and TGF ß2, separately. To evaluate proliferation, the total number of cells on the culture dish was counted with Coulter counter at 48hr after exposure. To evaluate collagen synthesis, Type 1 collagen in the conditioning medium was measured with enzyme–linked immunosorbent assay kit at 24hr after exposure. To evaluate the corneal fibroblasts–derived contraction, HCFs were cultured on collagen gel, the thickness of the gel was measured daily for 3 days and compared with original thickness. Results: The total cell number of the dishes exposed PP2 and TGF ß2(0.8 ± 0.3 ×10⁴ cells) were significantly less than of the dishes exposed PP3 and TGF ß2(1.4 ± 0.2 ×10⁴ cells) (p =0.0013). The amount of type 1 collagen of the dishes exposed PP2 and TGF ß2(520 ± 81 ng/ml) were significantly less than of the dishes exposed PP3 and TGF ß2(869 ± 187 ng/ml) (p =0.0066). The gels exposed PP3 and TGF ß2 (69.5 ± 4.9 %) significantly contracted than the gels exposed PP2 and TGF ß2(99.9 ± 0.6 %)(p < 0.0001) . Conclusions: Inhibitor of FAK significantly blocked activation of corneal fibroblasts induced by TGF ßin terms of proliferation, collagen synthesis, and contraction. These findings suggest that Inhibitor of FAK may be useful for suppressing excessive corneal stromal wound healing.

Keywords: cornea: stroma and keratocytes • wound healing • cornea: basic science