The Effects of Mononuclear Cell Factor/Interleukin-1 on the Plasminogen Activators Produced by Human Chondrocytes

Human chondrocytcs were stimulated with mononuclcar cell factor (MCF) and the distribution of plasminogen activator (PA) activity in culture media and cell fractions was studied. Most of the PA activity was cell associated, mainly with a 100000 g paniculate fraction MCF appeared to stimulate increased PA activity in the culture medium PAs present in culture media and paniculate fractions were studied using sodium dodecyl sulphate polyacrylamide gel clcctrophorcsis (SDS-PAGE) with gels containing casein and plasminogen. Bands of PA activity observed in the culture media had apparent molecular weights (mol.wt) ∼ 50000. 65000 and 100000. MCF stimulation caused enhanced production of the PA species with apparent mol.wts ∼ 65000 and 100000. PA activities detected in the paniculate fractions also had apparent mol wts ∼ 50000. 65000 and 100000 On MCF stimulation the activity, apparent mol wt ∼ 65000 was enhanced The release of PAs into culture medium on MCF stimulation and the enhanced production of certain PA species may increase the potential of PAs to mediate cartilage matrix destruction