Immunofluorescence evaluation of fibronectin, collagen IV, and laminin in RPE cells. The expression of fibronectin, collagen IV, and laminin was evaluated after incubation with 24 h in RPE cells under high glucose conditions. The RPE cells showed more intense staining under high glucose conditions compared with NG. (a) fibronectin; (b) collagen IV; (c) laminin. DAPI: blue.