Analysis of foreign protein overproduction in recombinant CHO cells. Effect of growth kinetics and cell cycle traverse.
Intracellular foreign protein (beta-galactosidase) expression in recombinant CHO cell lines in continuous culture was analyzed by developing a mathematical model that includes the effects of metabolic burden and cell cycle dependence of intracellular foreign protein expression. This combined growth kinetic and cell cycle model, assuming S- or G1-phase-dependent expression, was stimulated to predict productivity on a single-cell and culture-volume basis in continuous cultures. In the case of S-phase-dependent expression, the intracellular foreign protein level increases monotonically, but in the case of G1-phase-dependent expression it decreases monotonically with increasing dilution rate. Also, the trends of foreign protein concentration in the culture volume differ significantly between S- and G1-dependent expression kinetics. Thus, the cell cycle dependency of foreign protein expression should be included in process optimization concepts and operating strategies of continuous bioreactors.
Gu
M B
MB
Department of Chemical Engineering, University of Colorado, Boulder 80309-0424.
Todd
P
P
Kompala
D S
DS
D000818:Animals; D016466:CHO Cells / Q000166:cytology / Q000378:metabolism*; D002453:Cell Cycle; D002455:Cell Division; D006224:Cricetinae; D004274:DNA, Recombinant / Q000235:genetics; D005818:Genetic Engineering; D007700:Kinetics; D008954:Models, Biological; D011994:Recombinant Proteins / Q000096:biosynthesis* / Q000235:genetics; D001616:beta-Galactosidase / Q000096:biosynthesis / Q000235:genetics
D004274:DNA, Recombinant; D011994:Recombinant Proteins; D001616:beta-Galactosidase