Robotic selection for the rapid development of stable CHO cell lines for HIV vaccine production
Fig 4
Growth and expression of the 5F MGAT1- CHO cell line expressing A244_N332-rgp120 in shake flask cultures.
Cells were cultured under standard conditions until day 6 when 1 mM Sodium butyrate was added, and the temperature shifted to 32°C. Panels A-C: cells were fed with CHO Feed A and yeastolate as indicated, and harvested at day 13 (data from 3 shake flasks averaged). (A) Timecourse graph of viable cell densities (VCD) determined by trypan-blue exclusion on a BioRad T20 cell counter. (B) Timecourse of cell viabilities determined by trypan-blue exclusion. (C) Timecourse of A244_N332-rgp120 protein accumulation determined by ELISA. Panels D-F demonstrate optimization of protein expression (at >1g/L) by use of different feed additives. Five duplicate pairs of cultures were fed (as indicated) with CHO Feed C and either yeastolate (BD, Franklin Lakes NJ), cottonseed, wheat, pea hydrolsate (Friesland Camparia, Delhi, NY) or CD-hydrolysate (SAFC, Calsbad CA) at days 6, 8 and 10, and harvested at day 12 (data from each pair of shake flasks is averaged). (D) Timecourse graph of viable cell densities (VCD) determined by trypan-blue exclusion on a BioRad T20 cell counter. (E) Timecourse of cell viabilities determined by trypan-blue exclusion. (F) Timecourse of A244_N332-rgp120 protein accumulation determined by ELISA.