Expression, production and renaturation of a functional single-chain variable antibody fragment (scFv) against human intercellular adhesion molecule-1 (ICAM-1)

Abstract

The single-chain variable antibody fragment (scFv) against human intercellular adhesion molecule-1 (ICAM-1) was expressed at a high level in Escherichia coli as inclusion bodies. We attempted to refold the scFv by ion-exchange chromatography (IEC), dialysis and dilution. The results show that the column chromatography refolding by Q Sepharose high performance (Q HP) had remarkable advantages over the conventional dilution and dialysis methods. Furthermore, the anti-ICAM-1 scFv yield was higher by this method, which is about 60 mg/l. The purity of the final product was greater than 90%, as shown by denaturing gel electrophoresis. Enzyme-linked immunosorbent assay (ELISA), cell culture and animal experiments were used to assess the immunologic properties and biologic activities of the renatured scFv.