Structure of an affinity-matured inhibitory recombinant fab against urokinase plasminogen activator reveals basis of potency and specificity.

ABSTRACT: Affinity maturation of U33, a recombinant Fab inhibitor of uPA, was used to improve the affinity and the inhibitory effect compared to the parental Fab. Arginine scanning of the six CDR loops of U33 was done to identify initial binding determinants since uPA prefers arginine in its primary substrate binding pocket. Two CDR loops were selected to create an engineered affinity maturation library of U33 that was diversified around ArgL91 (CDR L3) and ArgH52 (CDR H2). Biopanning of the randomized U33 library under stringent conditions resulted in eight Fabs with improved binding properties. One of the most potent inhibitors, AB2, exhibited a 13-fold decrease in IC50 when compared to U33 largely due to a decrease in its off rate. To identify contributions of interfacial residues that might unde

SUBMITTER: Sevillano N 

PROVIDER: S-EPMC7770097 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature