Figure 3.
Effect of cathepsin B inhibition. (A) Vesicles shed from CABA I were isolated and tested for their ability to stimulate HUVEC invasiveness at pH 5.6 and 7.4, either with or without the cysteine proteinase inhibitor E-64 (50 µM). Data (mean ± SD of three independent experiments) represent the number of cells that had migrated in five high-power fields expressed in percentage, counting untreated cells as 100%, P < .05. (B) Zymographic analysis of vesicle-associated gelatinases incubated with inhibitor E-64 0 to 50 µM.