Generation of Protease Inhibitory Antibodies by Functional In Vivo Selection

Targeting dysregulated protease expression and/or abnormal substrate proteolysis, highly selective inhibition of pathogenic proteases by monoclonal antibodies (mAbs) presents an attractive therapeutic approach for the treatment of diseases including cancer. Herein, we report a functional selection method for protease inhibitory mAbs by periplasmic co-expression of three recombinant proteins-a protease of interest, an antibody Fab library, and a modified β-lactamase TEM-1. We validate this approach by isolation of highly selective and potent mAbs inhibiting human matrix metalloproteinase 9 (MMP9).