Fig 1: Effects of AA and DHA on actin ring formation and CTR expression.Osteoclast differentiation was stimulated in CD14+ monocytes by the addition of 25 ng ml-1 M-CSF and 30 ng ml-1 RANKL as described in Materials and Methods. Vehicle (0.08% ethanol) or LCPUFAs (40 µM) were added from day 3 in differentiating osteoclasts and from the onset of resorption (day 12–14) in mature osteoclasts. After 3 weeks of culture, cells were fixed and stained with Hoechst (blue) for nuclei, phalloidin (red) for actin rings, and anti-CTR antibody (green). The results are representative of three independent experiments conducted in triplicate. Scale bar = 200 µm. Diff Ocl—differentiating osteoclasts. Mat Ocl—mature osteoclasts.