Abstract:
:Several experimental data on continuous cultures of hybridoma cells show that monoclonal antibody productivity is a decreasing function of dilution rate. It has been suggested that this unusual behavior may be due to the arrest of a fraction of cycling cells at a critical point of Phase G(1). Although this hypothesis has been recently investigated by using population balance models, mathematical analysis has been performed without accounting for the dynamics of the arrested cells properly. In this article, a more general and accurate approach is presented and new specific assumptions are introduced to characterize the arrest and the later progress through the cycle. Two different models (stochastic and deterministic) and two different critical points for the arrest (at the beginning and at the end of G(1)) are considered. The cell cycle parameters are estimated so that data predicted by the model fit those reported in the literature. In particular, the fraction of arrested cells, the cell arrest probability, and the mean cell generation time are computed as functions of the dilution rate. Results so far obtained predict that there is an optimal value of dilution rate for maximizing specific production rate of monoclonal antibody.
journal_name
Biotechnol Bioengjournal_title
Biotechnology and bioengineeringauthors
Cazzador L,Mariani Ldoi
10.1002/bit.260421109subject
Has Abstractpub_date
1993-12-01 00:00:00pages
1322-30issue
11eissn
0006-3592issn
1097-0290journal_volume
42pub_type
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