Investigation of Decreased Antigen Binding Observed in the Cell Culture Development of a Monoclonal Antibody

摘要

Binding activity decrease with increased cell culture time was likely caused by protein deamidation in the bioreactor. Deamidation sites were identified using peptide mapping of WCX fractions. As a result, cell culture pH and temperature were tightly controlled. Cell culture time was shortened to avoid the significant deamidation and resultant loss of activity. In addition, the downstream process will be controlled to avoid additional deamidation.