| In this study we demonstrate that seprase and the urokinase plasminogen activator receptor ( uPAR ) , co localize in the plasma membrane of LOX malignant melanoma cells . ^^^ Cells were labeled with fluorochrome conjugated monoclonal antibodies ( mAb ) directed against seprase and uPAR . ^^^ This indicates that seprase and uPAR are within approximately 7 nm in the plasma membrane of LOX cells . ^^^ When LOX cells adhered to a 3D extracellular like matrix , seprase uPAR complexes were found to be associated with invadopodia . ^^^ Further microscopy experiments demonstrated gelatinolytic activity , a functional attribute of seprase , in association with seprase uPAR membrane domains . ^^^ |