Effects of temperature shift on cell cycle, apoptosis and nucleotide pools in CHO cell batch cultues

• Published in: Cytotechnology (Dordrecht) Vol. 23; no. 1-3; pp. 47 - 54
• Main Authors: MOORE, A, MERCER, J, DUTINA, G, DONAHUE, C. J, BAUER, K. D, MATHER, J. P, ETCHEVERRY, T, RYLL, T
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer 1997; Springer Nature B.V; Kluwer Academic Publishers
• Subjects: Animal cells; Apoptosis; Batch culture; Biological and medical sciences; Biotechnology; Cell culture; Cell cycle; Cell death; Energy charge; Establishment of new cell lines, improvement of cultural methods, mass cultures; Eukaryotic cell cultures; Fundamental and applied biological sciences. Psychology; Methods. Procedures. Technologies; S phase; Temperature effects; Viability; Cell culture; Temperature; Rodentia; Environmental factor; CHO cell line; Ovary; Vertebrata; Mammalia; Batchwise; Cell death; Animal; Cell cycle; Nucleotide; Viability; Hamster; Apoptosis
• ISSN: 0920-9069; 1573-0778
• DOI: 10.1023/a:1007919921991

Temperature reduction in CHO cell batch culture may be beneficial in the production of recombinant protein and in maintenance of viability. The effects on cell cycle, apoptosis and nucleotide pools were studied in cultures initiated at 37°C and temperature shifted to 30 °C after 48 hours. In control cultures maintained at 37 °C, viable cells continued to proliferate until the termination of the culture, however, temperature reduction caused a rapid decrease in the percent of cells in S phase and accumulation of cells in G-1. This was accompanied by a concurrent reduction in U ratio (UTO/UDP-GNAc), previously shown to be a sensitive indicator of growth rate. Culture viability was extended following temperature shift, as a result of delayed onset of apoptosis, however, once initiated, the rate and manner of cell death was similar to that observed at 37 °C. All nucleotide pools were similarly degraded at the time of apoptotic cell death. Temperature reduction to 30 °C did not decrease the energy charge of the cells, however, the overall rate of metabolism was reduced. The latter may be sufficient to extend culture viability via a reduction in toxic metabolites and/or limitation of nutrient deprivation. However, the possibility remains that the benefits of temperature reduction in terms of both viability and productivity are more directly associated with cultures spending extended time in G-1.