Structure and secretory activity of cultured chondrocytes from patients with osteoarthritis.

ABSTRACT

Cartilage samples were taken from OA patients in order to describe and quantify pro-inflammatory mediators. Samples were cultured under aseptic conditions in Dulbeccos modified Eagle medium at 37 degrees C for 10 days. Control samples, taken from non-inflammatory cartilage, were cultured under the same conditions. The levels of NO(-)2 and NO(-)3 were measured in the supernatant using a spectrophotometric assay. The activity of MMP-1 was quantified by ELISA. The concentration of NO(-)x was 47.3 +/- 4.1 microM in the OA cartilague and 10.7 +/- 1.8 microM in the controls. The average MMP-1 activity was 3,650 +/- 387 ng/ml in the OA cartilage and 2,150 +/- 190 ng/ml in the control samples. These increased values of MMP-1 and NO(-)x observed in the OA cartilage suggest a higher catabolic activity. A morphological analysis of OA chondral tissue using light microscopy shows that the surface of the tissue is characterized by the presence of aggregated chondrocytes or [quot ]clones[quot ] but in the deeper areas isolated cells are found. These results could be a significant contribution towards the identification of biological markers indicating the presence of OA activity.