Toward the complete characterization of host cell proteins in biotherapeutics via affinity depletions, LC-MS/MS, and multivariate analysis

摘要: Host cell protein (HCP) impurities are generated by the host organism during production of therapeutic recombinant proteins, and difficult to remove completely. Though commonly present in small quantities, if levels not controlled, HCPs can potentially reduce drug efficacy cause adverse patient reactions. A high resolution approach for thorough HCP characterization monoclonal antibodies is presented herein. In this method, antibody samples first depleted via affinity enrichment (e.g., Protein A, L) using milligram quantities material. The HCP-containing flow-through then enzymatically digested, analyzed nano-UPLC-MS/MS, proteins identified through database searching. Nearly 700 were from with very low total (< 1 ppm ∼10 ppm) method. Quantitation individual was performed normalized spectral counting as number peptide spectrum matches (PSMs) per proportional prot...