Incorporating shaken 24-deep-well plate fed-batch culture shortens CHO cell line development time

In conventional Chinese hamster ovary (CHO) cell line development, static culture is used for early-stage screening, whereas suspension culture is generally used for the manufacturing process. Shaken flask (SF) fed-batch culture allows evaluation with culture mode, which is closer to the final process. However, due to its laborious and low-throughput characteristics, only a limited number of clones can be evaluated. To attain high-throughput fed-batch culture evaluation, a shaken 24-deep-well plate (24 DWP) culture process was developed. 24 DWP culture allows multiple plates to be run in parallel, and is therefore suitable for early-stage screening. One challenge of well plate culture is the nonuniform evaporation rate among wells, which may result in unnecessary bias on clone evaluation. The 'sandwich lid system' introduced here provides a uniform evaporation rate, and showed no significant difference in cell culture performance by well location. 192 antibody-producing CHO clones were evaluated by 24 DWP fed-batch culture, and 30 clones were selected. On comparison of clone sets selected by 24 DWP fed-batch culture and the conventional scheme, average antibody concentration in SF fed-batch culture was 3.6 g/L and 2.9 g/L, respectively. 24 DWP fed-batch culture process showed a high correlation ratio with SF fed-batch culture in antibody productivity and similar cell culture characteristics. These characteristics-high-throughput and sufficient culture volume to support cell culture performance monitoring-indicate that 24 DWP fed-batch culture can be applied in the clone selection stage in place of SF, and will shorten the time required for cell line development.