CMC R&D Laboratories, Pharmaceutical Division, Kirin Brewery Company Limited, 100-1 Hagiwara, Takasaki, Gunma, 370-0013, Japan,
Cytotechnology. 2006 Nov;52(3):199-207. doi: 10.1007/s10616-007-9059-2. Epub 2007 Mar 8.
Controlling cell proliferation during cell culturing is an effective way to improve the production yield in mammalian cell culture. We examined the effect of temperature shifts (TS) under pH control conditions in Chinese hamster ovary cells. When we shifted the culture temperature from 37 degrees C to 31 degrees C before a stationary phase at pH 6.8 (TS/pH 6.8), cell viability remained high, and the final human monoclonal antibody (hMab) concentration increased to 2.3 times that in the culture remaining at 37 degrees C. However, there were no significant effects on the cell viability or production yield with the same TS at pH 7.0 (TS/pH 7.0). The average specific hMab productivity and mRNA level of TS/pH 7.0 were the same as that of TS/pH 6.8. The control of cell growth by the TS or the addition of rapamycin was effective in the maintenance of cell viability, but there was no significant increase of the average specific hMab productivity in the culture where cell proliferation was controlled with rapamycin. The hMab mRNA concentration decreased to 55%-65% at a 37 degrees C culture with the addition of actinomycin D. In contrast, actinomycin D did not affect the mRNA level in the TS culture. This result suggested that the increase in the mRNA level in the TS condition was caused by an increase in mRNA stability. In this study, we show that TS can produce two unrelated effects: a prolongation of cell longevity and an improvement in mRNA stability.
在细胞培养过程中控制细胞增殖是提高哺乳动物细胞培养生产产量的有效方法。我们研究了在 pH 控制条件下温度变化（TS）对中国仓鼠卵巢细胞的影响。当我们将培养温度从 37°C 转移到 pH 值为 6.8 的静止期之前的 31°C（TS/pH 值为 6.8）时，细胞活力仍然很高，最终的人单克隆抗体（hMab）浓度增加到 37°C 培养物的 2.3 倍。然而，在 pH 值为 7.0 时进行相同的 TS 对细胞活力或生产产量没有显著影响（TS/pH 值为 7.0）。TS/pH 值为 7.0 的平均特定 hMab 生产力和 mRNA 水平与 TS/pH 值为 6.8 的相同。通过 TS 或添加雷帕霉素控制细胞生长对维持细胞活力有效，但在使用雷帕霉素控制细胞增殖的培养物中，平均特定 hMab 生产力没有显著增加。加入放线菌素 D 后，37°C 培养物中的 hMab mRNA 浓度下降到 55%-65%。相比之下，放线菌素 D 对 TS 培养物中的 mRNA 水平没有影响。这一结果表明，TS 条件下 mRNA 水平的增加是由于 mRNA 稳定性的增加引起的。在这项研究中，我们表明 TS 可以产生两种不相关的效果：延长细胞寿命和提高 mRNA 稳定性。
