Figure 2.

Suppression of neutrophil-mediated proteoglycan degradation by inhibitors of PI3-K. Neutrophils (4 × 10⁶) were preincubated with various concentrations of wortmannin (a) or LY294002 (b), or with wortmannin (150 nm) (c) for 15 min before being added to labelled bovine articular cartilage in the presence (a and b) or absence (a–c) of TNF-α. Proteoglycan degradation was assessed as described in the Materials and Methods. Results, as means ±SEM of three experiments performed in triplicates and using cells from different donors (a and b) or means ±SEM of six replicate incubations using cells from the synovial fluid of two juvenile rheumatoid arthritis patients (c), are expressed as percentage of ³⁵S-labelled proteoglycan released in the absence of inhibitor and TNF-α over 150 min. Significance of difference between the presence and absence of inhibitor (anova) (a and b): 0·05 < P < 0·001; between the presence and absence of wortmannin (c):* P < 0·001.