Figure 4. In vitro masson and safranin-O staining of the chondrocyte sheets in different groups (n=3). (A–C) Masson staining magnification 20 times (bar 500 μm). (D–F) Zoom square magnification x200; bar 50 μm. (G–I) Safranin-O staining magnification 20 times (bar 500 μm). (J–L) Zoom square magnification x200; bar 50 μm.