Construction,expression and functional characterization of the β-lactamase with αv integrin ligands

Antibody-directed enzyme prodrug therapy (adept) delivers chemotherapeutic agents at high concentration to tumor tissues while minimizing systemic drug exposure. β-lactamases are particularly useful enzymes for adept systems due to their unique substrate specificity,which allows the activation of a variety of lactam-based prodrugs with minimal interference from mammalian enzymes. this study used integrin αvβ3 as a target for tumor-specific delivery of β-lactamase. β-lactamase was fused with acdcrgdcfcg peptide (rgd4c) by recombinant dna technology. likewise,this study cloned a fused cdna and successfully expressed active recombinant protein in e. coli purified with ni-nta resin. after purification,the protein showed the expected size of 42 kda on tricine-sds-page,and was further confirmed by western blotting. based on flow cytometric analysis,the purified protein was found to be active for specificity in breast cancer cell line,mcf-7,which supports the utility of the protein as an agent for adept. © 2010 bentham science publishers ltd.