Enhancing monoclonal antibody production efficiency using CHO-MK cells and specific media in a conventional fed-batch culture

Chinese hamster ovary (CHO) cell lines, derived as subclones from the original CHO cell line, are widely used hosts for current biopharmaceutical productions. Recently, a highly proliferative host cell line, CHO-MK, was established from the Chinese hamster ovary tissue. In this study, we assessed the fundamental culture characteristics and capabilities of CHO-MK cells for monoclonal antibody (mAb) production using specified chemically defined media. To achieve this, we established fed-batch cultures of model CHO-MK cells in shake flasks and ambr15 and 2 L bioreactors under various conditions. The mAb-producing CHO-MK cell line A produced 12.6 g/L of antibody within 7 days in the fed-batch culture using a 2 L bioreactor, with a seeding density of 1 × 10⁶ cells/mL. This performance corresponded to a space–time yield of 1.80 g/L/day, representing a productivity level that could be challengingly attained in fed-batch cultures using conventional CHO cells. In addition, when we subjected six different mAb-producing CHO-MK cell lines to fed-batch culture in the ambr15 bioreactor for 7 days, the antibody production ranged between 5.1 and 10.8 g/L, confirming that combining CHO-MK cells and specified media leads to enhanced versatility. These discoveries underscore that CHO-MK cells combined with specified media might represent a next-generation production platform, which could potentially respond to an increasing demand for antibody drugs, reducing production costs, and shortening antibody drug development times. This study is expected to serve as a benchmark for future production process development using CHO-MK cells.