底物限制对杂交瘤细胞生长、代谢和单抗生成的影响

Effects of Limited Substrates on the Growth, Metabolism and Monoclonal Antibody Formation of Hybridoma Cells

考察了葡萄糖或谷氨酰胺限制的批培养中杂交瘤细胞的生长、代谢和单抗生成。葡萄糖或谷氨酰胺限制时最大活细胞密度基本相同,为(1.0±0.1)×106cells/mL。葡萄糖限制时,乳酸生成减少,YLac/Glc降低,YCell/Glc增加,提示葡萄糖更多地参与三羧酸循环。谷氨酰胺限制时,氨和丙氨酸生成减少,YAmm/Gln增加,YAla/Gln减小,提示谷氨酰胺的能量利用率提高。谷氨酰胺缺失时异亮氨酸、亮氨酸、胱氨酸、缬氨酸、色氨酸、组氨酸等替代谷氨酰胺,维持细胞生长和单抗合成,产物是甘氨酸和天冬氨酸。单抗生成与细胞生长关联,并且细胞停止生长后单抗仍生成。细胞死亡阶段的qMAb约是生长阶段的一半。葡萄糖和谷氨酰胺共限制下细胞对单抗的生产能力比葡萄糖和谷氨酰胺单独限制时小。

The growth, metabolism and MAb formation of hybridoma cells were studied in the glucose or glutamine limited batch culture. Almost the same maximum viable cell densities, (1.0±0.1)×106 cells/mL in both cultures, were obtained. In glucose limitation, lactate production and YLac/Glc decrease, while YCell/Glc increases, which suggests that more glucose takes part in TCA cycle. In glutamine limitation, the production of ammonium and alanine, and YAla/Gln decrease, while YAmm/Gln increases, which indicates that the high utilization rate of glutamine is achieved. When glutamine is exhausted, some amino acids, such as isoleucine, leucine, cystine, valine, tryptophan and histine, are used to maintain cell growth and MAb formation. These amino acids are transformed into glycine and aspartate rather than alanine. MAb formation is growthassociated and continued during the death phase. The average specific MAb formation rates of the death phase are about half of those of the growth phase. The cell productivity in the combined glucose and glutamine limited batch culture is lower than that in the single glucose or glutamine limited batch culture.