Figure 2

Ephrin B2 (a) gene expression level in human normal (n = 5) and osteoarthritic (OA) (n = 4) chondrocytes, and (b) protein production as analyzed following immunohistochemistry as described in Materials and Methods in the superficial zone in normal (n = 4) and OA (n = 6) cartilage. Of note, the arbitrary unit of the ephrin B2 ligand gene is expressed as × 10^-3. (c) Representative immunohistological sections showing ephrin B2 in the superficial zone of human normal and (d) OA cartilage and (e) the deep zone of human normal and (f) OA cartilage. The insets represent in (c) a negative control done with immunoabsorption with only background staining and in (e) a higher magnification of positive cells stained for ephrin B2. c, d, e, f and inset in c: original magnification ×100, and inset in e: original magnification ×400. Arrows indicate stained chondrocytes. Statistical significance assessed by Student's t-test revealed no difference.