Expression of junctional adhesion molecule-C (JAM-C) in mouse arthritic synovium and synovial fibroblasts. Expression of JAM-C was examined by immunohistochemistry in knee joints of mice with antigen-induced arthritis (AIA) (a) and in paws of mice with K/BxN serum transfer-induced arthritis (b). The left panels show expression of JAM-C in the synovial lining layer (upper panel) and associated with blood vessels in the sublining (lower panel). The right panels show negative control sections incubated with preimmune serum. Original magnification × 400 (scale bar = 20 μm). (c) Reverse transcriptase-polymerase chain reaction (PCR) analysis of JAM-C mRNA expression in mouse synovial tissue samples and in cultured mouse synovial fibroblasts. A representative agarose gel electrophoresis of PCR products is shown. AIA1 and AIA2, antigen-induced arthritis synovial tissue; bp, base pairs; H2O, polymerase chain reaction negative control; K/BxN1 and K/BxN2, K/BxN serum transfer-induced arthritis synovial tissue; mSF1 and mSF2, two different mouse synovial fibroblast cultures isolated from antigen-induced arthritis synovial tissue; RTneg, non reverse-transcribed sample.