Figure 3. Immunohistochemical analysis of extracellular matrix in porous gelatin hydrogels with corneal fibroblasts or fibroblast precursors. Corneal fibroblasts or fibroblast precursors were seeded onto porous gelatin hydrogels and cultured for one week. A: Scanning electron microscopy revealed a porous structure for the gelatin hydrogels. B: Hematoxylin and eosin staining and immunohistochemical analysis of vimentin and ECM in porous gelatin hydrogels seven days after seeding of corneal fibroblasts or fibroblast precursors are shown. Vimentin staining was more intense in the gelatin hydrogels with corneal fibroblast precursors than in those with corneal fibroblasts (arrows). Other ECM components such as laminin, type I collagen, and type IV collagen are not expressed in the gelatin hydrogels with corneal fibroblasts or fibroblast precursors before transplantation except for a weak expression of laminin in the gelatin hydrogels with corneal fibroblast precursors (arrow). Scale bar=200 μm in B.