High-Throughput IgG Reformatting and Expression Using Hybrid Secretion Signals and InTag Positive Selection Technology.

We have previously published protocols for high-throughput IgG reformatting and expression, that enable rapid reformatting of phage-displayed antibody Fab fragments into a single dual expression vector for full IgG expression in Expi293F cells (Chen et al. Nucleic Acids Res 42:e26, 2014; Chen et al. Methods in Molecular Biology, vol 1701, 2018).

Attenuated glutamine synthetase as a selection marker in CHO cells to efficiently isolate highly productive stable cells for the production of antibodies and other biologics.

Chinese hamster ovary (CHO) cells are the biopharmaceutical industry's primary means of manufacturing therapeutic proteins, including monoclonal antibodies. The major challenge in cell line development for the production of recombinant biopharmaceuticals lies in generating and isolating rare high-producing stable clones, amongst thousands of low-producing or unstable clones, in a short period of time. One approach to accomplish this is to use the glutamine synthetase (GS) selection system, together with the GS inhibitor, methionine sulfoximine (MSX).