School of Medicine

The ability of the TGF-β1 inhibitor LY2157299 to block the higher PRG4 secretion stimulated chondrocytes cultured in OA SF suggests that TGF-β1 is involved in the higher levels of PRG4 secretion seen in osteoarthritis. OA SF has been found to have higher PRG4 levels than NL SF (1). Thus, we concluded that the higher PRG4 secretion by chondrocytes incubated in OA SF was due to stimulation by TGF-β1 in the OA SF.