High-Yielding CHO Cell Pools for Rapid Production of Recombinant Antibodies

Abstract

Cambridge Antibody Technology (CAT) has developed a system using GS-CHO transfectant pools to rapidly produce gram amounts of multiple IgGs for early characterisation studies and expedite drug development. The system involves screening a small number of independent pools by assessment of IgG harvest titre from terminal cultures or by flow cytometric analyses of intracellular IgG, which allows a more rapid ranking of pool performance. The highest-yielding pools are then expanded for production and can express up to 1.4 g/L at 5 L bioreactor scale in 7.5 weeks from transfection. Other GS-CHO transfectant pools have been scaled up to 50 L in disposable wavebags, and pools have been shown to be suitable for scaleup beyond 100 L, allowing the rapid production of tens of grams of IgG. The pools and manufacturing clonal cell lines at CAT use the same host cell type, expression system and production process therefore minimising the potential for differences in product characteristics at different stages of drug development. Productive pools have also been cloned out to identify high-yielding cell lines that show similar productivities to more conventionally isolated clonal cell lines, thereby potentially efficiently integrating rapid supply of antibody for early testing with manufacturing cell line development.