The paracrine action of ADAMTS1 on FPS cell invasion. (A) FPS cells were treated with V CM, P CM or P CM incubated with IgG or ADAMTS1 antibody for immunoneutralisation. Cell invasion through a monolayer of extracellular matrix was assessed after 24 hrs using a Boyden chamber assay. * represents statistical significance; P < 0.05. (B) FPS cells were treated with control (serum-free medium; SF) or SF medium with the addition of 1 or 10nM recombinant ADAMTS1 and cell invasion through a monolayer of extracellular matrix was assessed. * represents statistical significance of treated group relative to control; P < 0.05. Data are represented as mean ± SEM from at least 3 independent experiments.