Figure 3.

Cell transfection and antibody expression. (A) Schematic comparison of previously reported HEK293-F and the Expi293F expression systems with regard to required time, process, culture volumes, and antibody yields. (B) Flow cytometric dot plots depicting percentage of human IgG positive Expi293F cells 3 days post-transfection with anti-HER2 constructs. Cells were permeabilized and stained with anti-human IgG FITC; untransfected Expi293F cells (unstained and stained) were used as controls. (C) Effect of antibiotic selection addition at different times post Expi293F transfection with anti-HER2 wild-type (WT) construct—post-purification yields per mL of cell culture supernatant. Data from two independent experiments ± SD. (D) Concentration of WT anti-HER2 and anti-chondroitin sulfate proteoglycan 4 (CSPG4) antibodies per mL of cell culture supernatant over time measured by enzyme-linked immunosorbent assay. Data from two independent experiments ± SD.