The Effects of pH on Cell Growth, Monoclonal Antibody Expression and Quality of a Recombinant CHO Strain

doi:10.13560/j.cnki.biotech.bull.1985.2015.12.037

Abstract

Abstract: It was to study the effect of pH on the growth, monoclonal antibody expression and produce quality of a rewmbinant CHO strain. The results showed that the optimal pH for cell growth and the production of monoclonal antibody(mAb)was 7.05. Under this pH, a peak viable cell density was 1.54×10⁷cells/mL at day 9 and the highest harvested antibody concentration was 1 355.71 mg/L after cultivating for 11 days. In addition, pH significantly affected the accumulation of pCO₂ and lactate in cell cultures, as well as the expressed product's quality including its monomer ratio, charge variant species, and glycosylation pattern. While pH ranging from 6.95 to 7.25, cell cultures at higher pH reduced pCO₂ and the accumulation of lactate, but led the alkaline peak of antibody increase. Cultures at 2 sets of pH decreased the cell activity, therefore increased the expression of antibody.

Key words: pH, CHO cell, antibody, pCO₂, charge variants

Xiao Shang, Deng Chongfei, Ke Jun, Yan Chengwei, Sun Wenzheng, Yang Bin. The Effects of pH on Cell Growth, Monoclonal Antibody Expression and Quality of a Recombinant CHO Strain[J]. Biotechnology Bulletin, 2015, 31(12): 256-261.

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