A Comparative Investigation of the Bispecific Antibody: Expression in Expi293F Cells and E.coli

Abstract

Aims: Dual-Character antibodies can simultaneously target two surface markers. Blinatumomab is a C19 / CD3 antibody from the BiTE family (Bispecific T cell engager antibody) and was approved by the US Food and Drug Administration for clinical use. This antibody effectively targets malignant cells in patients with acute infoblastic leukemia. In the production of large quantities of such antibodies on an industrial scale, selecting the appropriate host remains a critical issue. Mammalian cells and strains of E.coli are the most common hosts for producing antibodies and antibody components on an industrial scale, respectively. Methods & Materials: In this study, a dual-specific antibody was used in the mammalian system of plasmid pcDNA3.1 (+) and for expression in the bacterial system of plasmid pET22b. The antibody produced in both systems was purified using nickel affinity resin under similar conditions. Next, SDS-PAGE and Western blot analysis was performed on both study samples. Finally, the binding properties of the antibody secreted from both systems were assessed by the ELISA test. Findings: The present study results suggested that antibodies produced by the mammalian expression system provided better binding properties than the expression system in bacteria. Conclusion: This study indicated that in the case of antibodies to two traits of the BiTE family, like Blinatombe, mammalian cells generate a more efficient and successful expression system; although the bacterium can produce much larger amounts of the antibody.