Figure 2From: Bacterial lipopolysaccharides form procollagen-endotoxin complexes that trigger cartilage inflammation and degeneration: implications for the development of rheumatoid arthritisLPS induced cellular and matrix degradation and apoptosis in cartilage tissue. Primary human chondrocytes were either left untreated (a) or were treated with 100 ng/ml lipopolysaccharides (LPS) (b-d), pretreated with BMS-345541 (5 mM) (e-g), wortmannin (20 nM) (h-j) followed by LPS treatment, or pretreated in combination with BMS-345541 and wortmannin (5 mM and 20 nM) (k-m) for 12 h and then stimulated with LPS for another 24 h. The cells were transferred to high-density culture for 14 days. Ultrastructural morphology was evaluated by electron microscopy. Control cultures of chondrocytes showed well-developed chondrocytes (Ch) embedded in a well-developed extracellular matrix (ECM) (a). Treatment with LPS resulted in matrix breakdown and cell lysis and apoptosis (arrows) (b-d). Pretreatment with BMS-345541 alone (e-g), with wortmannin alone (h-j) or in combination with BMS and wortmannin (k-m) resulted in a marked improvement of chondrocyte phenotype and the formation of cartilage nodules. The formation of a dense extracellular matrix (ECM) surrounding well-developed chondrocytes (Ch) was observed. Magnification x5000; bar, 1 µm.Back to article page