Isolation and characterization of an inhibitory human monoclonal antibody specific to the urokinase-type plasminogen activator, uPA.

The serine protease urokinase (uPA, urokinase-type plasminogen activator) is over-expressed in certain tumors and is considered to be the strongest single indicator of poor prognosis in patients with metastatic breast cancer. In this article, we describe the isolation and affinity maturation of a fully human recombinant antibody (termed DS2), specific to the human uPA and capable of inhibiting its enzymatic activity with an IC(50) value in the low nanomolar range. The novel antibody cross-reacts with murine uPA.