Figure 1: Vitreous down-regulated bevacizumab activity. An in vitro HUVEC scratch-wound assay was performed to examine the effect of vitreous on bevacizumab activity on VEGF. (A-J) Representative phase contrast images to show the proliferation and migration of HUVEC in the denuded area produced by pipette tip scrapping. (A) Untreated control; (B) cells treated with VEGF (10 ng/ml); (C) VEGF and bevacizumab (312 µg/ml); (D) VEGF and bevacizumab pre-incubated at 37°C for 7 days; (E) VEGF and bevacizumab pre-incubated in native vitreous at 37°C for 7 days; (F) VEGF and bevacizumab pre-incubated in denatured vitreous at 37°C for 7 days (G) VEGF and native vitreous; (H) VEGF and denatured vitreous; (I) native vitreous and (J) denatured vitreous. (K) A schematic diagram showing the six images captured in the scratch-wound assay. VEGF, vascular endothelial growth factor.