PRG4 and rheumatoid arthritis: The objective of this investigation was to evaluate the ability of rhPRG4 and native human PRG4 (nhPRG4) to bind to toll-like receptors 2 and 4 (TLR2 and TLR4) and whether this interaction will provide an anti-inflammatory effect by preventing TLR2 and TLR4 activation by agonists and by ligands in SF from patients with OA and RA.