Metabolic Flux Distributions in Hybridoma Cells at Different Metabolic States

Abstract

The metabolic state, specifically the conversion ofnutrients to lactate and other metabolites, of hybridomacells can be manipulated in afed-batch culture by controlling the level of glucose. When cultivated in continuous cultures, these different metabolic states result in multiple steady states marked by different cell, residual nutrient and metabolite concentrations. Most notably, the ratio of lactate produced to glucose consumed was markedly different. To better understand the underlying mechanisms of these metabolic states, metabolic flux analysis was performed. The intracellular fluxes are greatly different in the glycolytic pathway and amino acid catabolism among these steady states. The fluxes in the high lactate producing state were much greater than in the “efficient” state. The comparative analysis of intracellular fluxes lends credence to the idea of metabolic overflow in the excessive production of the metabolic by products: lactate and ammonia