Institute of Applied Biotechnology, Biberach University of Applied Sciences, Biberach, Germany.
Biotechnol Bioeng. 2018 May;115(5):1173-1185. doi: 10.1002/bit.26534. Epub 2018 Jan 22.
Protein aggregation of monoclonal antibodies (mAbs) is a common phenomenon associated with the production of these biopharmaceuticals. These aggregates can lead to adverse side effects in patients upon administration, thus expensive downstream processing steps to remove the higher molecular weight species are inevitable. A preferable approach is to reduce the level of aggregation during bioprocessing by a careful adjustment of critical process parameters. Recently, new analytical methods enabled characterization of mAb aggregation during bioprocessing of mammalian cells. Furthermore, rapid and efficient bioprocess optimization has been performed using design of experiments (DoE) strategies. In this work, we describe a DoE-based approach for the analysis of process parameters and cell culture additives influencing protein aggregation in Chinese hamster ovary (CHO) cell cultures. Important bioprocess variables influencing the aggregation of mAb and host cell proteins were identified in initial screening experiments. Response surface modeling was further applied in order to find optimal conditions for the reduction of protein aggregation during cell culture. It turned out that a temperature-shift to 31 °C, osmolality above 420 mOsm/kg, agitation at 100 rpm and 0.04% (w/v) antifoam significantly reduced the level of aggregates without substantial detrimental effects on cell culture performance in our model system. Finally, the aggregation reducing conditions were verified and applied to another production system using a different bioprocess medium and another CHO cell line producing another mAb. Our results show that protein aggregation can be controlled during cell culture and helps to improve bioprocessing of mAbs, by giving insights into the protein aggregation at its origin in mammalian cell culture.
单克隆抗体（mAbs）的蛋白质聚集是与这些生物制药生产相关的常见现象。这些聚集体在给予患者时会导致不良的副作用，因此不可避免地需要昂贵的下游处理步骤来去除更高分子量的物质。一种较好的方法是通过仔细调整关键工艺参数来降低生物处理过程中的聚集水平。最近，新的分析方法使我们能够在哺乳动物细胞的生物处理过程中对 mAb 聚集进行表征。此外，还使用实验设计（DoE）策略进行了快速有效的生物处理优化。在这项工作中，我们描述了一种基于 DoE 的方法，用于分析影响中国仓鼠卵巢（CHO）细胞培养物中 mAb 和宿主细胞蛋白聚集的工艺参数和细胞培养添加剂。在初始筛选实验中确定了影响 mAb 和宿主细胞蛋白聚集的重要生物处理变量。进一步应用响应面建模，以找到在细胞培养过程中降低蛋白质聚集的最佳条件。结果表明，将温度升高至 31°C，渗透压高于 420mOsm/kg，搅拌速度为 100rpm，消泡剂用量为 0.04%（w/v），可在不显著影响细胞培养性能的情况下，显著降低聚集体的水平。最后，验证了降低聚集的条件，并将其应用于使用不同生物处理培养基和生产另一种 mAb 的不同 CHO 细胞系的另一个生产系统。我们的结果表明，通过深入了解哺乳动物细胞培养中蛋白质聚集的起源，可以在细胞培养过程中控制蛋白质聚集，有助于改善 mAb 的生物处理。
