Figure 1 .

RANKL detected with mAb 626/immunoperoxidase and AEC (red), in synovial tissue from a patient with RA with (A) active disease and (B) inactive disease, (C) a patient with SpA, and (D) a patient with OA. (E) to (H) identify cell lineages expressing RANKL (mAb 626/immunoperoxidase (red)) using dual immunohistochemical labelling on serial synovial biopsy sections from a patient with RA with active disease. RANKL expression is identified by mAb 626 using an AEC/immunoperoxidase technique combined with an immunohistochemical alkaline phosphatase technique using fast blue to identify cell surface markers. (E) Dual labelling with anti-CD3 (blue) and both (purple), (F) B cell antibody anti-CD22 (blue), (G) monocyte/macrophage lineage anti-CD68 (blue) and both (purple), (H) FLS with anti- CD55/fast blue (blue). All magnifications taken at x20.