Effects Of Growth Factors On Proliferation Of Bovine Lens Epithelial Cells

Abstract

Abstract: : Purpose:Lens epithelial cell proliferation is an important step in the pathogenesis of secondary cataract formation after extracapsular cataract extraction. This study investigates the effects of four different growth factors (bFGF, EGF, IGF-1, TGFß₂) on proliferation of bovine lens epithelial cells (BLEC). Methods:BLECs were cultured in the presence of 1 to 50 ng/ml basic fibroblast growth factor (bFGF), epidermal growth factor (EGF), insulin-like growth factor-1 (IGF-1), or transforming growth factor-ß₂ (TGFß₂) for 40 h in serum deprived medium, containing [₃H]-thymidine over the last 16 h. In all experiments untreated serum free negative controls were used. (₃H)-thymidine incorporation as a direct measure of BLEC proliferation was assessed by liquid scintillation counting. Statistical analysis was performed using paired student's t-test. Results:BLEC proliferation was statistically significant (p<0.05) increased by bFGF (1+10 ng/ml), EGF (5,10+20 ng/ml) and IGF-1 (1,5+10 ng/ml). In contrast, TGFß₂ inhibited statistically significant the proliferation of BLEC at all concentrations ≤ 50 ng/ml (p<0.05). Conclusion:Our data shows that various growth factors have a concentration-dependent modulatory effect on the proliferation of bovine lens epithelial cells in vitro. The factors bFGF, EGF and IGF-1 had an stimulatory influence on BLEC proliferation, whereas TGFß₂ showed an inhibitory effect on proliferation. The anti-proliferative properties of TGFß₂ or the potential inhibition of the stimulatory effect of bFGF, EGF and IGF-1 could be of possible therapeutic value for prevention of postoperative secondary cataract formation.

Keywords: 338 cataract • 423 growth factors/growth factor receptors