表达HSA/IL2的重组CHO细胞的无血清培养基优化研究

Optimization of Serum-Free Medium for Culturing Recombined CHO Expressing HSA/IL2

摘要:

优化适合重组CHO细胞生长及表达人血清白蛋白与白介素2（HSA/IL2）的低成本无血清悬浮培养基。以无血清悬浮培养基M1为基础，考察了3种不同质量浓度（1.0、2.5、5.0、10.0 g/L）的蛋白水解物（酵母提取物（YE）、大豆蛋白胨（Soy）及胰蛋白胨（Tyr））对CHO细胞生长、细胞周期、细胞凋亡及HSA/IL2融合蛋白表达的影响。5 g/L的YE促进细胞生长，提高HSA/IL2表达量的效果最佳。流加培养过程中，在含5.0 g/L YE的培养基中CHO细胞密度可达9.95×106 cells/mL，HSA/IL2表达量提高至104.06 mg/L，分别是对照组的1.42倍和1.51倍。细胞对数生长期时，YE可以提高细胞周期进展而利于细胞生长；细胞表达期时，YE可以提高细胞G1期比例，延长细胞表达期时间而利于HSA/IL2表达。

Abstract:

To optimize a serum-free medium for high cell density of CHO cells expressing HSA/IL2.CHO expressing HSA/IL2 cells were cultured in M1 medium supplemented with three kinds of hydrolysate[yeast extract（YE），soytone（Soy）and tryptone（Tyr）]and different concentrations[1.0，2.5，5.0，10.0 g/L]to evaluate the effects of additives on cell density，cell viability，cell cycle，apoptosis and protein expression level. M1 medium supplemented with 5.0 g/L YE could significantly promote cell growth and enhance the expression level of HSA/IL2. The maximum viable cell density was 9.95×106 cells/ml and the expression level of HSA/IL2 reached 104.06 mg/L，respectively，which represent an increase of 42% and 51% in comparison with the control group. In addition，YE affected cell cycle in different cell culture phases. In logarithmic growth phase，YE could increase the percent of S phase for cell growth；In the stationary phase，YE could increase the percent of G1 phase for enhancing protein expression.