Figure 4

Activation of plasminogen bound to enolase. A Ability to hydrolyze chemical substrates. Plasminogen was placed in microtiter plates coated with rEno or BSA in the presence or absence of ε-ACA. Bound plasminogen was activated by tPA. A plasmin-specific substrate was added, and the OD value was measured at 405 nm. Wells without tPA served as negative controls. B rEno enhances the activation of plasminogen by tPA. Plasminogen was pre-incubated with rEno or PBS prior to the addition of tPA. Activation of plasminogen was measured by adding a plasmin-specific substrate. Wells without Plg or tPA added served as negative controls. C Degradation of reconstituted ECM. Matrigel was reconstituted on the surface of the transwell membrane. rEno-harboring or BSA-harboring polystyrene beads, treated with plasminogen and tPA, were added to the upper compartment of the transwell and incubated for 40 h. The surface of transwell membranes was analyzed by SEM. C-2 and C-4 are enlarged views of parts of C-1 and C-3, respectively. Results are expressed as means ± SD of three experiments with triplicate samples (**p < 0.01).