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

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.