Open AccessZinc supplementation increases protein titer of recombinant CHO cells
Author(s) -
Berta Capella Roca,
Antonio Alarcón Miguez,
Joanne Keenan,
Srinivas Suda,
Niall Barron,
Donal J. O'Gorman,
Padraig Doolan,
Martin Clynes
Publication year - 2019
Publication title -
cytotechnology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.488
H-Index - 62
eISSN - 1573-0778
pISSN - 0920-9069
DOI - 10.1007/s10616-019-00334-1
Subject(s) - titer , zinc , chinese hamster ovary cell , recombinant dna , chemistry , cell culture , microbiology and biotechnology , biochemistry , biology , antibody , receptor , immunology , genetics , organic chemistry , gene
In order to study the impact of zinc and copper on the titer levels of mAb and recombinant protein in CHO cells, the IgG-expressing (DP12) and EPO-expressing (SK15) cell lines were cultured in chemically defined media with increasing concentrations of either metal. Supplementation with 25 mg/l in CDM media resulted in a significant increase in EPO (1.7-fold) and IgG (2.6-fold) titers compared to control (no added zinc). Titers at this Zn concentration in CDM containing the insulin replacing agent aurintricarboxylic acid (ATA) (CDM + A) showed a 1.8-fold (EPO) and 1.2-fold (IgG) titers increase compared to control. ATA appeared to also reduce the specific productivity (Qp) enhancement induced by Zn-25, with up to 4.9-fold (DP12) and 1.9-fold (SK15) Qp increase in CDM compared to the 1.6-fold (DP12) and 1.5-fold (SK15) Qp increase observed in CDM + A. A 31% reduced Viable Cell Density (VCD) in DP12 was observed in both Zn-supplemented media (3 × 10 6 cells/ml vs 4.2 × 10 6 cells/ml, day 5), whereas SK15 Zn-25 cultures displayed a 24% lower peak only in CDM + A (2.2 × 10 6 cells/ml vs 3.2 × 10 6 cells/ml, day 5). Supplementation with copper at 13.7-20 mg/l resulted in less significant cell line/product-type dependent effects on titer, VCD and Viability. Analysis of the energetic phenotype of both cell lines in 25 mg/l Zn-supplemented CDM media revealed a twofold increase in the oxygen consumption rate (OCR) compared to non-supplemented cells. Together, these data suggest that high zinc supplementation may induce an increase in oxidative respiration metabolism that results in increased Qp and titers in suspension CHO cultures.