Fig. 4.

Fractalkine (10 nM) was added to osteoarthritis (OA) fibroblasts for the times indicated and cell lysates were generated. Protein (20 µg/lane) was separated using polyacrylamide gel electrophoresis and blotted using standard Western techniques. Phosphorylated extracellular signal-regulated kinase (ERK) 1/2 is compared with total Erk 1/2 to assure equal loading. Bars represent normalized band intensity in arbitrary units. Blots are representative of three different experiments performed using OA fibroblasts from three different patients.