The Adaptation of Chinese Hamster Ovary Cells to Hypothermic Temperatures Increases Yields of Monomeric Recombinant Interferon-beta
| dc.contributor.author | Sunley, Kevin | |
| dc.contributor.examiningcommittee | Huebner, Erwin (Biological Sciences) Behie, Leo (University of Calgary) Mark, Brian (Microbiology) | en |
| dc.contributor.supervisor | Butler, Mike (Microbiology) | en |
| dc.date.accessioned | 2009-09-04T19:18:19Z | |
| dc.date.available | 2009-09-04T19:18:19Z | |
| dc.date.issued | 2009-09-04T19:18:19Z | |
| dc.degree.discipline | Microbiology | en_US |
| dc.degree.level | Doctor of Philosophy (Ph.D.) | en_US |
| dc.description.abstract | Mild hypothermic conditions (30ºC to 33ºC) have previously been shown to increase cell specific productivity (Qp) of recombinant proteins from mammalian cells. However, this is often associated with a lower growth rate which off-sets any potential advantage of higher product titres. This thesis describes the isolation of a novel population of Chinese Hamster Ovary (CHO) cells that have been adapted to low temperature growth by continuous subculture at low temperature for a duration of 400 days. This adapted cell population achieved a growth rate 2-fold greater than non-adapted cells under low temperature conditions (32ºC) while maintaining an elevated level of cell specific expression of recombinant beta-interferon. The volumetric titre of beta-interferon was enhanced by 70% in stationary cultures and by more than 2-fold by application of a temperature-shift strategy involving a growth to production phase. However, the low temperature-adapted cells were fragile and demonstrated an increased sensitivity to hydrodynamic stress in agitated cultures. This problem, caused by a weakened vimentin intermediate filament network, was resolved by the use of macroporous microcarriers which were demonstrated to entrap and protect the cold-adapted cells. Cold-adapted microcarrier cultures were able to achieve high cell densities (greater than 5x10^6 nuclei/mL) cultures under hypothermic conditions. This resulted in a 3-fold enhancement of volumetric titre of monomeric beta-interferon compared to the original control culture at 37ºC. | en |
| dc.description.note | October 2009 | en |
| dc.format.extent | 41540714 bytes | |
| dc.format.mimetype | application/pdf | |
| dc.identifier.uri | http://hdl.handle.net/1993/3192 | |
| dc.language.iso | eng | en_US |
| dc.rights | open access | en_US |
| dc.subject | CHO | en |
| dc.subject | interferon | en |
| dc.subject | recombinant | en |
| dc.subject | hypothermic | en |
| dc.subject | adaptation | en |
| dc.subject | protein | en |
| dc.subject | biopharmaceutical | en |
| dc.subject | manufacturing | en |
| dc.title | The Adaptation of Chinese Hamster Ovary Cells to Hypothermic Temperatures Increases Yields of Monomeric Recombinant Interferon-beta | en |
| dc.type | doctoral thesis | en_US |