Global phosphoproteomic study of high/low specific productivity industrially relevant mAb producing recombinant CHO cell lines

Abstract

Understanding the biology of CHO cells at a cellular level is extremely valuable to the pharmaceutical industry, as it presents the opportunity to rationally engineer clonally derived cell lines (CDCLs) with elevated recombinant specific productivity (Qp). To date, relatively little is understood about the intracellular pathways which influence desirable phenotypes in CHO cell lines. In this study we identified phosphoproteins and total proteins which are differentially expressed between high and low Qp IgG4 producing industry CHO cell lines, some of which upon further investigation, could potentially be used as targets to engineer high Qp CDCLs. We highlighted the importance of phosphoproteins and total proteins associated with amino acid sensing in high Qp cell lines. We also identified increased expression of proteins which promote progression through the cell cycle in low Qp cell lines, suggesting that lower Qp CDCLs are focusing their translational machinery on translating cell cycle associated mRNAs.

Keywords

• Chinese hamster ovary (CHO) cells
• Label free quantitative proteomics
• Phosphoproteomics
• Cell specific productivity (Qp)
• Biopharmaceuticals