Evaluation of a multimodal resin for selective capture of CHO-derived monoclonal antibodies directly from harvested cell culture fluid

• Multimodal chromatography was examined for capturing recombinantly produced mAbs directly from mammalian HCCF.
• Four elution strategies were identified that could be applied with minimal optimization to other mAb feedstocks.
• Similar purity is achieved after two chromatography steps when comparing multimodal and affinity capture steps.

This proof-of-concept study examines the applicability of using multimodal chromatography to selectively capture recombinantly produced monoclonal antibodies (mAb) directly from harvested mammalian cell culture fluid (HCCF) with minimal optimization. Capto MMC is a multimodal resin that contains a ligand with the potential to participate in ionic, hydrophobic, and hydrogen boding interactions with proteins and is coupled to a highly cross-linked agarose bead matrix. Twelve mAb HCCF feedstocks were examined for dynamic binding capacity (DBC) and then two representative feedstocks were selected to develop a systematic approach for elution buffer development. A range of dynamic binding capacities was observed for 10 feedstocks (24–53 g/L) and two feedstocks had poor binding properties (<10 g/L) despite load conditioning towards a more favorable pH. Analysis of the DBC versus molecular properties showed that the mAb-ligand binding interaction was predominantly charge based. Four separate elution strategies were identified to selectively recover the mAb and could be applied with minimal optimization to other mAb feedstocks. Downstream processing of the Capto MMC pools showed that it is feasible to produce material with comparable purity to a process with affinity capture after two chromatography steps.