Researchers from Tokyo University of Science (TUS) have found a simple, low-cost way to optimise the production of monoclonal antibodies (mAbs) and reduce manufacturing costs.
Dr Kyohei Higashi, Associate Professor at TUS, along with a team of researchers, conducted a study to explore the effects of polyamines on N-linked glycan profiles of mAbs in CHO DP-12 cells.
“Because the carbohydrate structure of mAbs changes depending on the state of the cells, we were interested in investigating the relationship between intracellular polyamines and the carbohydrate structure of mAbs from CHO cells,” explained Dr Higashi.
Cutting the cost of antibody production
CHO cells cannot produce polyamines in serum-free media, which results in a decrease in intracellular polyamine levels, which causes a low growth rate and cell viability during long-term cultivation.
Intracellular polyamine levels can also be decreased by treatment with α-difluoromethylornithine (DFMO). This can then be reversed by the addition of spermidine (SPD) to the growth media of CHO cells.
Upon introducing DFMO to the CHO cells, the team observed that IgG antibody galactosylation surged, along with an increase in the levels of β1,4-galactosyl transferase 1 (B4GALT1) mRNA. This mRNA is pivotal in governing the IgG galactosylation mechanism within CHO cells. What’s more, IgG production decreased by approximately 30% in DFMO-treated cells.
Dr Higashi hypothesised that the decrease in IgG production was a result of endoplasmic stress (ER) stress response caused by polyamine depletion. During ER stress response, protein folding ceases, resulting in the arrest of the normal function of cells. Chaperone proteins assist in the correct folding of other protein classes and play a crucial role under both normal and stress conditions.
“Introducing polyamines, particularly SPD, to serum-free culture medium for CHO cells may contribute to consistent manufacturing and quality control of antibody production. We hope that this research will contribute to the stable production of antibody drugs and lead to lower drug prices,” concluded Dr Higashi.