P10: Bispecific Antibody production in E. coli: Half the Story

Humanized monospecific antibodies are convenient therapeutics when the antigen is a well defined single target, however many disease states are complex and may require targeting more than one antigen at the same time.  Thus, bispecific antibodies (bsAbs) are being developed by companies in an attempt to target two different cell surface receptors, two different cytokines or to elicit T-cell mediated killing of cancer cells.

Genentech has an interest in making bsAbs in an effort to provide therapies for unmet medical needs. The production of half antibodies (hAbs) in E. coli requires the optimization of a number of cellular processes within two distinct compartments (cytoplasm and periplasm) and across a single membrane (inner membrane). Over the past decade a number of technologies have been tested as well as developed at Genentech that aid in the production of antibodies in E. coli.  In the cytoplasm, the translational levels of both the light and heavy chains can be optimized by varying the translational initiation region (TIR). Folding and assembly of light and heavy chains in the periplasm can be optimized with the use of general chaperones, peptidyl-proyl isomerases, oxidoreducatses and disulfide bond isomerases. Our initial data indicates that optimization of TIRs, as well as the co-expression of chaperones and protein folding catalysts can help to increase half antibody titers and aid in the production of a variety of hAbs in E. coli.