Effect of PIN1 knockdown on calpain and cathepsin activity. Activities were determined from the initial rate of cleavage of fluorogenic substrates for calpain (A), or cathepsin (B). These were assessed in extracts of KD and Control cells treated with medium or LPS/IFN for 24 h. Bars represent mean + SE fluorescence increase/min for 4 independent cultures in each group. *: p < 0.05 for comparison with medium-treated cells. +: p < 0.05 for comparison between KD and Control MAEC treated in the same way.