Biologics Development, Global Product Development and Supply, Bristol-Myers Squibb Company, Devens, Massachusetts, USA.
Biotechnol Prog. 2022 Sep;38(5):e3268. doi: 10.1002/btpr.3268. Epub 2022 May 24.
Charge variants represent a critical quality attribute that must be controlled during the development and manufacturing of monoclonal antibodies (mAb). Previously, we reported the development of a cost-effective enzymatic treatment capable of removing the C-terminal lysine from a mAb produced by a Chinese hamster ovary (CHO) GS cell line. This treatment resulted in a significant decrease in basic charge variants and a corresponding improvement in the main peak, enabling a longer cell culture production duration for titer improvement. Here, we describe this enzymatic treatment protocol in detail and demonstrate its applicability to two additional mAbs produced by distinct industrial cell lines. The simple addition of carboxypeptidase B (CpB) at a ratio of 1:10,000 (w/w) to whole cell cultures significantly improved the main peaks for both mAbs without affecting other critical quality attributes, including size exclusion chromatography impurities and N-glycans. Our results demonstrate that this in vitro CpB treatment protocol can be used as a platform strategy to improve main peak for mAbs that exhibit high levels of basic variants attributable to C-terminal lysines. An in vitro enzymatic treatment in general may be another good addition to existing in vivo CHO cell culture strategies for titer improvement and control of critical quality attributes.
电荷变异体是单克隆抗体 (mAb) 开发和生产过程中必须控制的关键质量属性。此前，我们报道了一种经济有效的酶处理方法的开发，该方法能够从中国仓鼠卵巢 (CHO) GS 细胞系生产的 mAb 中去除 C 末端赖氨酸。该处理显著降低了碱性电荷变异体的含量，相应地改善了主峰，从而延长了细胞培养生产时间以提高滴度。在这里，我们详细描述了该酶处理方案，并证明其适用于另外两种由不同工业细胞系生产的 mAb。在整个细胞培养物中简单地添加 1:10,000 (w/w) 的羧肽酶 B (CpB) ，可显著改善两种 mAb 的主峰，而不会影响其他关键质量属性，包括尺寸排阻色谱杂质和 N-糖基化。我们的结果表明，该体外 CpB 处理方案可作为一种平台策略，用于改善由于 C 末端赖氨酸导致高水平碱性变异体的 mAb 的主峰。一般来说，体外酶处理可能是现有体内 CHO 细胞培养策略的另一个很好的补充，可用于提高滴度和控制关键质量属性。
