Cell culture hybridoma growth

The mammalian cell culture technique can be employed to produce clinically important biochemicals such as human growth hormones, interferon, plasminogen activator, viral vaccines, and monoclonal antibodies. Traditionally, these biochemicals had been produced using living animals or extracted from human cadavers. As examples, monoclonal antibodies can be produced by cultivating hybridoma cells in the peritoneal cavity of mice, and the human growth hormone to cure dwarfism can be extracted from human cadavers. However, the quantity obtained from these methods is quite limited for the wide clinical usages of the products. 

Culture medium osmolality has a large influence on animal cell culture. Hyperosmotic conditions, achieved by using salts, CO2, or concentrated media, has been shown as a low-cost method to increase specific productivity of cells. Hybridoma cultures, for instance, show improved productivity with an increase in osmolality (Oh et al., 1993). However, this method is not very popular due to the negative effects on cell growth. The drop in cell growth under hyperosmotic conditions occurs, probably, due to cell death by apoptosis. Thus, expression of anti-apoptotic genes, such as Bcl-2, could allow the use of hyperosmotic conditions to simultaneously limit cell death and increase cell productivity (Kim and Lee, 2002). 

Jeong YH, Wang SS (1995), Role of glutamine in hybridoma cell culture effects on cell growth, antibody production, and cell metabolism, Enzyme and Microbial Technology 17 47-55. 

Ozturk SS, Palsson BO (1991), Growth, metabolic, and antibody production kinetics of hybridoma cell culture 2. Effects of serum concentration, dissolved oxygen concentration, and medium pH in a batch reactor, Biotechnol. Prog. 7 481-494. 

Rpnning 0W, Schartum M, Winsnes A Lindberg G (1991) Growth limitation in hybridoma cell cultures the role of inhibitory or toxic metabolites. Cytotech-nology 7 15-24. 

Ramirez OT Mutharasan R (1990) Cell cycle- and growth phase-dependent variations in size distribution, antibody productivity, and oxygen demanding hybridoma cultures. Biotechnology and Bioengineering 36 839-848. 

The most common cell culture systems developed for pilot- and commercial-scale production of monoclonal antibodies (MAbs) are hollow-fibre and ceramic matrix modules, stirred bioreactors and airlift fermenters. These systems allow cultivation of cells in batch, fed-batch, continuous or perfusion mode. The selection of a culture system and culture mode for the large-scale production of a particular MAb should take into account the growth and antibody-production characteristics of the particular hybridoma line. This module therefore presents an overview of the important characteristics of these systems. Detailed descriptions with accompanying results and a large collection of cited literature are given elsewhere (Seaver, 1987 Mizrahi, 1989 sections 5.1 and 5.9). 

Frame KK Hu W-S (1991) Kinetic study of hybridoma growth in continuous culture. 1. A model for non-producing cells. Biotechnology and Bioengineering 37 55-64. 

Hiller GW, Clark DS Blanch HW (1993) Cell retention-chemostat studies of hybridoma cells - analysis of hybridoma growth and metabolism in continuous suspension culture in serum-free medium. Biotechnology and Bioengineering 42 185-195. 

The productivities of the different culture systems are compared in Table 5.9.6, with reference to viable cell numbers and monoclonal antibody productivity. Table 5.9.7 gives a prediction of the scale-up of hybridoma growth and productivity in fixed-bed Siran porous-glass-sphere reactors. 

Duval D, Geahel A, Dufau AF Hache J (1989) Effect of amino acids on the growth and productivity of hybridoma cell cultures. In Spier RE, Griffiths JB, Stephenne J Crooy PJ (eds) Advances in Animal Cell Biology and Technology for Bioprocesses, pp. 257-259. Butterworth, Oxford. 

Miller, W.M. Wilke, C.R. Blanch, H.W. Effects of dissolved oxygen concentration on hybridoma growth and metabolism in continuous culture. J. Cell Physiol. 1987, 132, 524-530. 

Mammalian growth usually shows respiratory quotients close to 1, that is, carbon dioxide formation (CER) equals oxygen uptake rate (OUR). With respect to the relatively poor mass transfer conditions installed in cell culture reactors (compared to microbial conditions), dissolved CO2 (dCOj) levels can accumulate during fed-batch processes. While optimum dC02 concentrations appear to be cell-specific, growth inhibiting partial pressures of approximately 100 mbar had been identified for, for example, hybridoma cells [81]. 

Growth of hybridoma cells in stationary monolayer cultures 130 Growth of hybridoma cells in Nunc Cell Factories 131... 

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