Antibody production

Abstract

The clinical and commercial success of monoclonal antibodies has led to the need for very large-scale production in mammalian cell culture. This has resulted in rapid expansion of global manufacturing capacity [1], an increase in size of reactors (up to 20,000 L) and a greatly increased effort to improve process efficiency with concomitant manufacturing cost reduction. This has been particularly successful in the upstream part of the process where productivity of cell cultures has improved 100 fold in the last 15 years. This success has resulted from improvements in expression technology and from process optimisation, especially the development of fed-batch cultures. In addition to improving process/cost efficiencies, a second key area has been reducing the time taken to develop processes and produce the first material required for clinical testing and proof-of-principle. Cell line creation is often the slowest step in this stage of process development. This article will review the technologies currently used to make monoclonal antibodies with particular emphasis on mammalian cell culture. Likely future trends are also discussed.

Expression of anti‐apoptosis genes alters lactate metabolism of Chinese Hamster Ovary cells in culture

“…The blank vector refers to the original pBUDCE4.1 vector. A model antibody (Ab #1) expression vector was constructed by cloning a Heavy and a Light chain cDNA into the Glutamine Synthase (GS) expression vector (obtained from Lonza Biologics under a research license [Birch and Racher, 2006]). …”

“…Hence CHOK1SV was subsequently used as the control cell line in all experiments. The most promising apoptotic R cell line, EAX197 as well as the control cell line were then used to develop production cell lines expressing a model antibody using the GS expression vector (Birch and Racher, 2006). Antibody in cell culture was measured by Nephelometry (Beckman Array System).…”

Microarray profiling of preselected CHO host cell subclones identifies gene expression patterns associated with in‐creased production capacity

“…The latter can be caused by both genomic changes and epigenetic regulation [17][18][19]. This genomic and phenotypic heterogeneity has advantages and disadvantages: On the one hand it allows the effective selection of cells with different physiological and process relevant properties during screening [6,[20][21][22][23][24][25], on the other hand it limits the stability of these properties [21,26,27] and requires large numbers of subclones to be tested over prolonged periods of time to identify the few stable clones suited for production. The endogenous heterogeneity present in CHO cells is further enhanced by the process of recombination and gene amplification during cell line development, where the gene of interest and selection markers are integrated at a random site into the host cell genome, which may cause knockout of genes as well as changes in their expression levels either by separation of genes from their genetic control elements or by co-amplification with the recombinant gene.…”

A serum substitute for fed-batch culturing of hybridoma cells

“…In vitro culturing of hybridoma cells has been extensively studied for a high production rate of monoclonal antibody for several decades, and many efficient nutrient feeding strategies have been developed (Glacken 1987;Bibila and Robinson 1995;Distefano et al 1996;Birch and Racher 2006). The most important strategy for doing fed-batch culture is to reduce the formation of byproducts, such as lactate and ammonia, and keep the nutrient concentration balanced and stable.…”

“…Their production can be partly decreased by reducing the glucose and glutamine concentrations in the medium. In recent studies, effective cultures of hybridoma and Chinese hamster ovary (CHO) cells have been developed through comprehensive research on nutrient metabolism (Bibila and Robinson 1995;Distefano et al 1996;Birch and Racher 2006). The models in these studies incorporated not only major pathways of glucose and glutamine metabolism but also pathways of other amino acids into the stoichiometric model.…”