Department of Biotechnology, VIBT, University of Natural Resources and Life Sciences, Vienna, Muthgasse 18, 1190, Vienna, Austria.
Department of Chemistry, VIBT, University of Natural Resources and Life Sciences, Vienna, Muthgasse 18, 1190, Vienna, Austria.
N Biotechnol. 2019 May 25;50:20-26. doi: 10.1016/j.nbt.2019.01.001. Epub 2019 Jan 7.
IgM antibodies are arousing considerable interest as biopharmaceuticals. Despite their immunotherapeutic potential, little is known about the impact of environmental conditions on product quantity and quality of these complex molecules. Process conditions influence the critical quality attributes (CQAs) of therapeutic proteins and thus are important parameters for biological safety and efficacy. Here, the results of a systematic study are presented that characterized the influence of temperature and pH on cell-specific productivity and IgM quality attributes. Biphasic temperature and pH shift experiments were performed as batch cultures in DASGIP bioreactors under controlled conditions and defined by a specific design of experiment (DOE) approach. An internally-developed recombinant IgM producing CHO cell line was used. With respect to product quality, after an initial purification step efforts were focused on pentamer content, nucleic acid (NA) impurities and the glycosylation profile after an initial purification step. All quality attributes were evaluated by densitometric and chromatographic methods. The reduction of cultivation temperature severely reduced IgM titers, while pH variation had no impact. In contrast, IgM quality was not significantly influenced by bioprocessing parameters. Data revealed that an additional purification step is required to reduce the presence of NAs for in vivo applications. In conclusion, the results showed that for the chosen IgM model, IgM012_GL, variation in quality attributes is not caused by the environmental conditions of temperature and pH.
IgM 抗体作为生物制药正引起相当大的兴趣。尽管它们具有免疫治疗的潜力，但人们对环境条件对这些复杂分子的产品数量和质量的影响知之甚少。工艺条件会影响治疗性蛋白的关键质量属性（CQAs），因此是生物安全性和疗效的重要参数。本文介绍了一项系统研究的结果，该研究描述了温度和 pH 值对细胞特异性产率和 IgM 质量属性的影响。在 DASGIP 生物反应器中作为分批培养进行两相温度和 pH 值转换实验，并通过特定的实验设计（DoE）方法进行控制和定义。使用内部开发的产生 IgM 的 CHO 细胞系。就产品质量而言，在初始纯化步骤后，重点关注五聚体含量、核酸（NA）杂质和初始纯化步骤后的糖基化谱。所有质量属性均通过密度计和色谱方法进行评估。降低培养温度会严重降低 IgM 效价，而 pH 值变化则没有影响。相比之下，生物加工参数对 IgM 质量没有显著影响。数据表明，对于选择的 IgM 模型 IgM012_GL，需要额外的纯化步骤来减少体内应用中 NA 的存在。总之，结果表明，对于所选的 IgM 模型 IgM012_GL，质量属性的变化不是由温度和 pH 值的环境条件引起的。
