AVT - Biochemical Engineering, RWTH Aachen University, Aachen, Germany.
Rentschler Biopharma SE, Laupheim, Germany.
Biotechnol J. 2022 Aug;17(8):e2100677. doi: 10.1002/biot.202100677. Epub 2022 Apr 11.
Shake flasks are frequently used for mammalian cell suspension cultures. For process development and routine culture monitoring, information on culture behavior is needed early on.
Here, cell-specific oxygen uptake rates (qO ) of two CHO cell lines were determined from shake flask experiments by simultaneous measurement of oxygen transfer rates (OTR) and viable cell concentrations (VCC). For cell line one, qO decreased from 2.38·10 to 1.02·10 mmol cell h during batch growth. For cell line two, qO was constant (1.90·10 mmol h ). Determined qO values were used to calculate the VCC from OTR data. Cumulated oxygen consumption and glucose consumption were correlated for both cell lines and enabled calculation of glucose concentrations from OTR data. IgG producing cell line one had an oxygen demand of ∼15 mmol g , cell line two consumed ∼5 mmol g . The established correlations for determination of VCC and glucose were successfully transferred to subsequent cultivations for both cell lines. Combined measurement of the OTR and the carbon dioxide transfer rate enabled quantitative determination of the lactate concentration (production and consumption) without sampling.
Taken together, non-invasive measurement of the respiration activity enabled time-resolved determination of key culture parameters for increased process understanding in shake flasks.
摇瓶常用于哺乳动物细胞悬浮培养。对于工艺开发和常规培养监测，需要尽早获得有关培养行为的信息。
在这里，通过同时测量氧传递速率（OTR）和活细胞浓度（VCC），从摇瓶实验中确定了两种 CHO 细胞系的细胞特异性耗氧率（qO ）。对于细胞系 1，qO 在批式生长过程中从 2.38·10 降至 1.02·10 。对于细胞系 2，qO 保持不变（1.90·10 ）。确定的 qO 值用于从 OTR 数据计算 VCC。两种细胞系的累积耗氧量和葡萄糖消耗量相关，可从 OTR 数据计算葡萄糖浓度。产生 IgG 的细胞系 1 的需氧量约为 15 mmol g ，细胞系 2 消耗约 5 mmol g 。用于确定 VCC 和葡萄糖的已建立相关性成功转移到了两种细胞系的后续培养中。OTR 和二氧化碳传递速率的联合测量可实现无需取样即可定量测定乳酸浓度（产生和消耗）。
总之，呼吸活性的非侵入性测量使我们能够在摇瓶中实时确定关键培养参数，从而提高对工艺的理解。
