Studying host cell protein interactions with monoclonal antibodies using high throughput protein A chromatography

• Published in: Biotechnology journal 2012-10, Vol.7 (10), p.1233-1241
• Main Authors: Sisodiya, Vikram N., Lequieu, Joshua, Rodriguez, Maricel, McDonald, Paul, Lazzareschi, Kathlyn P.
• Format: Article
• Language: English
• Subjects: Animals; Antibodies, Monoclonal - chemistry; Antibodies, Monoclonal - isolation & purification; Antibodies, Monoclonal - metabolism; CHO Cells; Chromatography, Affinity - methods; Cricetinae; Cricetulus; Downstream processing; Guanidine - chemistry; High-Throughput Screening Assays - methods; Host cell proteins; Hydrogen-Ion Concentration; Monoclonal antibodies; Protein A chromatography; Protein Binding; Protein interactions; Proteins - chemistry; Proteins - metabolism; Sodium Chloride - chemistry; Staphylococcal Protein A - chemistry; Staphylococcal Protein A - metabolism
• ISSN: 1860-6768; 1860-7314
• DOI: 10.1002/biot.201100479

Protein A chromatography is typically used as the initial capture step in the purification of monoclonal antibodies produced in Chinese hamster ovary (CHO) cells. Although exploiting an affinity interaction for purification, the level of host cell proteins in the protein A eluent varies significantly with different feedstocks. Using a batch binding chromatography method, we performed a controlled study to assess host cell protein clearance across both MabSelect Sure and Prosep vA resins. We individually spiked 21 purified antibodies into null cell culture fluid generated with a non‐producing cell line, creating mock cell culture fluids for each antibody with an identical composition of host cell proteins and antibody concentration. We demonstrated that antibody‐host cell protein interactions are primarily responsible for the variable levels of host cell proteins in the protein A eluent for both resins when antibody is present. Using the additives guanidine HCl and sodium chloride, we demonstrated that antibody‐host cell protein interactions may be disrupted, reducing the level of host cell proteins present after purification on both resins. The reduction in the level of host cell proteins differed between antibodies suggesting that the interaction likely varies between individual antibodies but encompasses both an electrostatic and hydrophobic component. Protein A chromatography is typically used as the initial capture step in the purification of monoclonal antibodies. Although exploiting an affinity interaction for purification, the level of host cell proteins in the protein A eluent varies significantly with different feedstocks. Using a high throughput batch binding method in conjunction with a library of monoclonal antibodies, the authors demonstrate that although the levels of host cell proteins in the protein A eluent can be influenced by the type of protein A resin, antibody‐host cell protein interactions are primarily responsible for the variable levels of host cell proteins following protein A chromatography.