Transcriptomic and Proteomic Analysis of Antibody Producing NS0 Cells Cultivated at Different Cell Densities in Perfusion Culture

Achieving higher cell densities in large-scale mammalian cell culture is one possibility to enhance the overall yield of therapeutic protein production. Maintaining higher cell densities resulted in relatively reduced proliferation rate, monoclonal antibody production and viability associated with process intensification in the perfusion bioreactor. Difference in gene and protein expression level between three different cell densities during perfusion period was obtained by use of Affymetrix microarrays and two dimensional gel electrophoresis /mass spectrometry, respectively. The expression of fifty-three genes and forty-seven proteins were significantly changed. These changes reflected the increased regulation in energy production and apoptosis pathways. Cellular stress response to mass transfer limitation at high cell density resulted in a deregulation of genes/proteins involved in antibody folding, assembly and secretion as well as upregulation of proteasome activity, hence, decreasing monoclonal antibody concentration with increasing cell density.