谷氨酰胺限制对rCHO细胞生长和代谢的影响

Effects of Limited Glutamine on Growth and Metabolism of rCHO Cells

考察了rCHO细胞(Ch inese ham ster ovary,中国仓鼠卵巢细胞)在批培养和谷氨酰胺限制流加培养过程中的生长、代谢特性。实验发现随着谷氨酰胺浓度的下降,谷氨酰胺的比消耗速率以及氨和丙氨酸的比生成速率显著下降。与批培养相比,在谷氨酰胺限制流加培养过程中,培养时间延长,活细胞密度增加,达到2.4×106cells/mL;谷氨酰胺的代谢途径发生改变,代谢副产物生成明显减少,YAmm/G ln由1.04 mm o l/mm o l略微下降到0.92 mm o l/mm o l,YA la/G ln由0.35 mm o l/mm o l下降到0.08 mm o l/mm o l,YX/G ln由0.383×109cells/mm o l增加至0.504×109cells/mm o l,YAmm/X由2.59×1-0 9mm o l/cell下降到1.85×1-0 9mm o l/cell,表明谷氨酰胺代谢的能量利用率显著提高,也证明其参与细胞合成代谢的分率增加。

The growth and metabolism of recombinant Chinese Hamster Ovary （rCHO） cells in batch and glutamine-limited fed-batch cultures were investigated in this work. The specific rates of glutamine consumption, ammonia and alanine production dramatically declined with the decrease of glutamine concentration. Compared to batch cultures, the maximum viable cell density and integral of viable cells over time （IVC） in glutamine-limited fed-batch culture achieved 2.4× 10^6 cells/mL and 15.8 × 10^9 cells · d/L respectively. It was found that, in glutamine-limited fed-batch culture, YAmm/Gln decreased from 1. 04 mmol/mmol to 0. 92 mmol/mmol, YAmm/X from 2. 59 × 10^-9 mmol/cell to 1. 85 × 10^-9 mmol/cell, Y Ala/Gln from 0. 35 mmol/mmol to 0. 08 mmol/mmol, but Y X/Gln. increased from 0. 383× 10^9 cells/mmol to 0. 504× 10^9 cells/mmol. These results showed that the energy consumption rate of glutamine metabolism was enhanced apparently with the decrease of waste-product formation, due to the control of low glutamine concentrations in culture environment through glutamine-limited feeding.