I liked your article, is the 2.5 g/l average you mentioned pretty reproducible for most CHO lines or do you see lots of variation in the titers?

Answer

Antibody yields following MaxCyte electroporation using a given expression system and downstream culture conditions is highly reproducible. In terms of the ability to achieve g/L productivity, it is dependent on a variety of factors including the vector, the protein being expressed, and as you inquired, is also dependent on the cell line being used (including different CHO lines). MaxCyte electroporation has yielded titers exceeding 1 g/L without process optimization (i.e., using commercial base media/feed with no adjustments to the metabolites or pH) in several CHO cell lines, including CHO-S, CHO-K1 and CHOK1SV. We can further increase productivity to multi-gram per liter titers following basic process optimization of feed strategy and media additives. Some CHO cell lines are more suited to transient production than others. For example, DHFR deficient CHO cells, such as DG44, can be transfected with high efficiency using the MaxCyte system, but sustained viability is more difficult, which results in lower transient titers compared to other CHO lines.