Fig. 5

No signs for inflammatory reaction in the DRG during acute synovitis. Ipsilateral DRG of both WT and S100a9^−/− mice were isolated and used for both RT-PCR of several genes involved in inflammation (n = 5) and for histological examination (n = 5). No significant differences in the expression of inflammation-related genes (MCP1 (a), S100A8 (b), IL-1B (c), and NGF (d)) were observed. When the tissue was examined histologically, the H&E staining (magnification × 200) did not show any alteration in mice injected with SCW from mice injected with saline. Also, no differences between WT and S100a9^−/− mice were observed (e). When monocytes/macrophages were specifically detected using F4/80 (magnification × 400), after quantification, no differences were observed between all groups (e, f)