Advantages and disadvantages of glucose limitation in perfused mammalian cell cultures

Abstract

Feeding strategies based on glucose limitation are becoming increasingly popular in mammalian cell cultivation. While until recently this approach has been limited to small-scale experiments, nowadays there is a considerable interest in its large-scale application. In order to investigate the overall effect of glucose limitation, we have applied this strategy to the industrial scale perfused cultivation of NSO myeloma cell line for antibody production. Glucose-limited and non-limited experiments were conducted in a 200 L sparged bioreactor, equipped with an external cell retention device. The experiments continued for several months at high cell density (20-60x106 cells/mL), which enabled the reliable monitoring of physiological phenomena with large time constants. A comprehensive set of process variables representing cell physiology and process efficiency were analyzed both in terms of statics and dynamics. Glucose limitation provides several important advantages, including control of the glucose metabolism, reduced lactate concentration, better medium utilization, and simple perfusion control. Apart from these advantages, however, glucose limitation provoked phenomena with profound effect on cell physiology and process efficiency. Based on our experimental data, it was concluded that glucose limited feeding has large potential for industrial application, but should be used cautiously, after careful evaluation of its long-term effect on the cell culture.