Representative effects of Src kinase inhibitor on extracellular proteases of Acanthamoeba . (A) A. castellanii were incubated in RPMI in the presence or absence of PP2 or PP3. Conditioned medium (CM) was collected and proteolytic activities determined using zymographic assays. Note that PP2, a specific Src kinase inhibitor blocked A. castellanii proteases. Results are representative of three independent experiments. (B) The density of the bands was quantitated using an imaging densitometer. Data represent the mean of three independent experiments, bars represent standard error.