谷氨酰胺限制对杂交瘤细胞生长、代谢和单抗生产的影响

Effect of Glutamine Limitation on Growth, Metabolism and MAb Production of Hybridoma Cells

利用批培养和流加培养方式以及不同的流加培养成分,考察了谷氨酰胺限制对杂交瘤细胞生长、代谢和单抗生成的影响。谷氨酰胺限制降低了最大细胞密度和单抗比生产速率,说明谷氨酰胺限制阻碍了细胞生长和单抗生产。谷氨酰胺限制流加培养的YLac/Gluc和YLac/Cells高于批培养和谷氨酰胺非限制流加培养的,说明谷氨酰胺限制促进了葡萄糖向乳酸的生成,增强了葡萄糖的溢流代谢。与批培养和谷氨酰胺非限制流加培养相比,谷氨酰胺限制流加培养的氨和丙氨酸浓度及其比生成速率较低,而且YAmm/Gln高,YAla/Gln和YAla/Cells低,说明谷氨酰胺限制使得较多的谷氨酰胺参与脱氢反应,提高了谷氨酰胺的利用率,降低了细胞对氨和丙氨酸的生成,从而削弱了氨对细胞生长和单抗生产的毒害。在流加培养中应严格控制谷氨酰胺的流加浓度及与葡萄糖的配比,要避免谷氨酰胺过分限制导致的葡萄糖溢流代谢和对细胞生长和单抗产率的不利效应。

The effect of glutamine limitation on the growth, metabolism and MAb production of hybridoma cells were investigated by using batch and fed-batch culture modes and different feeding medium components. The peak cell density and specific MAb production rate decrease under glutamine limitation, which indicates that glutamine limitation hinders cell growth and MAb production. The metabolite coefficients of YLac/Glus and YLac/Cells in the gin-limited fed-batch culture are higher than those in the batch and gin-non-limited fed-batch culture, it suggests that glutamine limitation promotes lactate formation from glucose and enhances glucose overflow metabolism. Compared with those in the batch and gin-non-limited fed-batch culture, the lower concentrations and specific formation rates of ammonium and alanine in the gin-limited fed-batch culture, and also the higher YAmm /Gln and lower YAIa/Gin and YAIa/Cetts in it, imply that glutamine limitation can cause more glutamine to be incorporated into dehydrogenation reaction, thus raising the effective utilization of glutamine. It was also found that in the gin-limited fed-batch culture the formation of ammonium and alanine by cells is declined, so that the damage to cell growth and MAb production caused by ammonium is relieved. The feeding glutamine level and the ratio of glutamine to glucose should be rigorously controlled to avoid the glucose overflow metabolism and negative effect on cell growth and MAb production induced by excessive glutamine limitation.