INFLUENCE OF AMMONIUM ION AND GLUCOSE ON MAB PRODUCTION IN SUSPENSIONAND FIXED-BED HYBRIDOMA CULTURES

Previous work indicated that mAb production by a mouse-mouse hybridoma , grown in a fixed bed of macroporous glass beads with a variable feed glutamine concentration, was correlated only to Qv(O2). The work repo rted in this study further investigated the metabolic parameters modul ating mAb production using metabolic data from a continuous stirred ta nk reactor (CSTR) to interpret the behaviour of cells grown in a fixed bed bioreactor (FBR). For a FBR culture grown with a feed glutamine c oncentration of 3 mmol l-1, Qv(mAb) was correlated to Qv(O2) and Qv(Gl n). However, if the feed glutamine concentration was switched between 1 and 3 mmol l-1, the above relationship did not hold, probably becaus e Qv(O2) was at or near its maximum value. For both the FBR and CSTR, switches in the feed glutamine concentration suggested that maximum Qv (mAb) values were associated with glucose concentrations above 12.8 mm ol l-1 and an ammonium concentration of 2.0-2.5 mmol l-1.