Fig. 4

Immunolocalization of lubricin in enzyme-treated cartilage explant after 1-week culture. Immunoreactivity for lubricin was positive in the superficial- to middle-zone chondrocytes (A, B), but not in the deep-zone chondrocytes (C). Lubricin expression was not apparent in migrating chondrocytes with elongated shape (A, right panel). The inset of the left panel shows a cell preparing to migrate out from the superficial zone. Arrows indicate pseudopodia (A, middle panel). Right panels of B and C indicate hyper-magnification of the dashed boxes in the respective left panels