IL-17A induces low-grade resorption. (a) Tartrate-resistant acid phosphatase (TRAP) staining of peripheral blood mononuclear cells isolated from healthy volunteers cultured for 14 days in the presence of macrophage colony-stimulating factor (MCSF) and increasing IL-17A concentrations. Data pooled from three individual experiments performed in triplicate. (b) Phaloidin and DAPI staining of CD14+ cells treated with IL-17A (1 ng/ml). (c) Scanning electron photomicrographs of CD14+ cells cultured for 21 days treated with IL-17A (1 ng/ml) on dentine slices in the presence of MCSF (25 ng/ml). Bars: left, 20 μm; right, 40 μm. Representative data of three individual experiments.