Figure 2.

Substantially higher antibody titers using optimized media. A total of 8 × 10⁷ CHO-S cells were electroporated with an antibody expression plasmid (2 µg DNA/1 × 10⁶ cells) using small-scale electroporation. Postelectroporation cells were seeded at 5 to 6 × 10⁶ cells/mL in CD CHO or CD OptiCHO media either supplemented or unsupplemented with commercially available nutrients. Sodium butyrate (1 mM) was added to all cultures and the temperature lowered to 32 °C 24 h postelectroporation. Cells were fed daily. (A) Cell viability was measured via trypan blue exclusion on days 0 to 14 postelectroporation. (B) Antibody titers were measured on days 3 to 14 postelectroporation.