Figure 7.

RANKL and OPG expression in the PsA synovium. Retrieval tissues containing synovium from PsA patients were processed for immunohistochemistry with antibodies specific for RANKL and OPG as described in Methods. A representative synovial membrane from a PsA patient stained with anti-RANKL antibody (a), anti-OPG antibody (b), secondary antibody only (c), and H&E (d) are shown photographed at ×20. Of note is the very specific and intense RANKL staining by synovial lining cells and the OPG staining restricted to the endothelial cells below the synovial lining.