Premium
Effect of Copper Sulfate on Performance of a Serum‐Free CHO Cell Culture Process and the Level of Free Thiol in the Recombinant Antibody Expressed
Author(s) -
Chaderjian Wendy B.,
Chin Edward T.,
Harris Reed J.,
Etcheverry Tina M.
Publication year - 2008
Publication title -
biotechnology progress
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.572
H-Index - 129
eISSN - 1520-6033
pISSN - 8756-7938
DOI - 10.1021/bp0497029
Subject(s) - chinese hamster ovary cell , recombinant dna , thiol , copper , chemistry , biochemistry , cell culture , antibody , oxidizing agent , copper sulfate , cysteine , sulfate , biology , enzyme , organic chemistry , immunology , genetics , receptor , gene
A recombinant Chinese hamster ovary (CHO) cell line was used to express a humanized antibody. Product quality analysis of this humanized antibody showed the presence of free thiol, due to unpaired cysteine residues in the Fab region. Decreased potency of this thiol Fab made it critical to minimize the levels of free thiol. In an effort to do this, we evaluated the effect of copper sulfate addition to the cell culture production medium. As a component of the production medium, copper sulfate can act as an oxidizing agent, thereby facilitating disulfide bond formation. Four concentrations of copper sulfate were added at the beginning of 2‐L benchtop production cultures of the recombinant CHO cell line: 0, 5, 50, and 100 μM. We found that these copper sulfate additions had no effect on cell growth or antibody production. However, a slight dose‐dependent depression in culture viability was observed. Analysis of the purified antibody showed that either the 50 or 100 μM copper sulfate additions reduced the level of free thiol by more than 10‐fold.