Multifunctional role of osteopontin in directing intrafibrillar mineralization of collagen and activation of osteoclasts.

摘要: Mineralized collagen composites are of interest because they have the potential to provide a bone-like scaffold that stimulates natural processes resorption and remodeling. Working towards this goal, our group has previously shown nanostructure bone can be reproduced using polymer-induced liquid-precursor (PILP) process, which enables intrafibrillar mineralization with hydroxyapatite achieved. This prior work used polyaspartic acid (pASP), simple mimic for acidic non-collagenous proteins, generate nanodroplets/nanoparticles an amorphous mineral precursor infiltrate interstices type-I fibrils. In study we show osteopontin (OPN) similarly serve as process-directing agent collagen, even though OPN is generally considered inhibitor. We also found inclusion in process promotes interaction mouse marrow-derived osteoclasts PILP-remineralized was demineralized, measured by actin ring formation. While osteoclast activation occurred when pASP agent, resulted dramatic effect on activation, presumably inherent arginine–glycine–aspartate ligands OPN. By capitalizing multifunctionality OPN, these studies may lead way producing biomimetic substitutes capability tailorable bioresorption rates.