GLORIA

GEOMAR Library Ocean Research Information Access

X

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Online Resource
    Online Resource
    Model‐based investigation of intracellular processes determining antibody Fc‐glycosylation under mild hypothermia
    Wiley ; 2017
    In:  Biotechnology and Bioengineering Vol. 114, No. 7 ( 2017-07), p. 1570-1582
    Details
    In: Biotechnology and Bioengineering, Wiley, Vol. 114, No. 7 ( 2017-07), p. 1570-1582
    Abstract: Despite the positive effects of mild hypothermic conditions on monoclonal antibody (mAb) productivity ( q mAb ) during mammalian cell culture, the impact of reduced culture temperature on mAb Fc‐glycosylation and the mechanism behind changes in the glycan composition are not fully established. The lack of knowledge about the regulation of dynamic intracellular processes under mild hypothermia restricts bioprocess optimization. To address this issue, a mathematical model that quantitatively describes Chinese hamster ovary (CHO) cell behavior and metabolism, mAb synthesis and mAb N‐linked glycosylation profile before and after the induction of mild hypothermia is constructed. Results from this study show that the model is capable of representing experimental results well in all of the aspects mentioned above, including the N‐linked glycosylation profile of mAb produced under mild hypothermia. Most importantly, comparison between model simulation results for different culture temperatures suggests the reduced rates of nucleotide sugar donor production and galactosyltransferase (GalT) expression to be critical contributing factors that determine the variation in Fc‐glycan profiles between physiological and mild hypothermic conditions in stable CHO transfectants. This is then confirmed using experimental measurements of GalT expression levels, thereby closing the loop between the experimental and the computational system. The identification of bottlenecks within CHO cell metabolism under mild hypothermic conditions will aid bioprocess optimization, for example, by tailoring feeding strategies to improve NSD production, or manipulating the expression of specific glycosyltransferases through cell line engineering. Biotechnol. Bioeng. 2017;114: 1570–1582. © 2016 The Authors. Biotechnology and Bioengineering Published by Wiley Periodicals Inc.
    Type of Medium: Online Resource
    ISSN: 0006-3592 , 1097-0290
    URL: Issue
    URL: Article
    DOI: 10.1002/bit.v114.7
    DOI: 10.1002/bit.26225
    Language: English
    Publisher: Wiley
    Publication Date: 2017
    detail.hit.zdb_id: 1480809-2
    detail.hit.zdb_id: 280318-5
    SSG: 12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 2
    Online Resource
    Online Resource
    How does mild hypothermia affect monoclonal antibody glycosylation?
    Wiley ; 2015
    In:  Biotechnology and Bioengineering Vol. 112, No. 6 ( 2015-06), p. 1165-1176
    Details
    In: Biotechnology and Bioengineering, Wiley, Vol. 112, No. 6 ( 2015-06), p. 1165-1176
    Abstract: The application of mild hypothermic conditions to cell culture is a routine industrial practice used to improve recombinant protein production. However, a thorough understanding of the regulation of dynamic cellular processes at lower temperatures is necessary to enhance bioprocess design and optimization. In this study, we investigated the impact of mild hypothermia on protein glycosylation. Chinese hamster ovary (CHO) cells expressing a monoclonal antibody (mAb) were cultured at 36.5°C and with a temperature shift to 32°C during late exponential/early stationary phase. Experimental results showed higher cell viability with decreased metabolic rates. The specific antibody productivity increased by 25% at 32°C and was accompanied by a reduction in intracellular nucleotide sugar donor (NSD) concentrations and a decreased proportion of the more processed glycan structures on the mAb constant region. To better understand CHO cell metabolism at 32°C, flux balance analysis (FBA) was carried out and constrained with exometabolite data from stationary phase of cultures with or without a temperature shift. Estimated fluxomes suggested reduced fluxes of carbon species towards nucleotide and NSD synthesis and more energy was used for product formation. Expression of the glycosyltransferases that are responsible for N‐linked glycan branching and elongation were significantly lower at 32°C. As a result of mild hypothermia, mAb glycosylation was shown to be affected by both NSD availability and glycosyltransferase expression. The combined experimental/FBA approach generated insight as to how product glycosylation can be impacted by changes in culture temperature. Better feeding strategies can be developed based on the understanding of the metabolic flux distribution. Biotechnol. Bioeng. 2015;112: 1165–1176. © 2014 Wiley Periodicals, Inc.
    Type of Medium: Online Resource
    ISSN: 0006-3592 , 1097-0290
    URL: Issue
    URL: Article
    DOI: 10.1002/bit.v112.6
    DOI: 10.1002/bit.25524
    Language: English
    Publisher: Wiley
    Publication Date: 2015
    detail.hit.zdb_id: 1480809-2
    detail.hit.zdb_id: 280318-5
    SSG: 12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 3
    Online Resource
    Online Resource
    Exploring cellular behavior under transient gene expression and its impact on mAb productivity and Fc‐glycosylation
    Wiley ; 2018
    In:  Biotechnology and Bioengineering Vol. 115, No. 2 ( 2018-02), p. 512-518
    Details
    In: Biotechnology and Bioengineering, Wiley, Vol. 115, No. 2 ( 2018-02), p. 512-518
    Abstract: Transient gene expression (TGE) is a methodology employed in bioprocessing for the fast provision of recombinant protein material. Mild hypothermia is often introduced to overcome the low yield typically achieved with TGE and improve specific protein productivity. It is therefore of interest to examine the impact of mild hypothermic temperatures on both the yield and quality of transiently expressed proteins and the relationship to changes in cellular processes and metabolism. In this study, we focus on the ability of a Chinese hamster ovary cell line to galactosylate a recombinant monoclonal antibody (mAb) product. Through experimentation and flux balance analysis, our results show that TGE in mild hypothermic conditions led to a 76% increase in q P compared to TGE at 36.5°C in our system. This increase is accompanied by increased consumption of nutrients and amino acids, together with increased production of intracellular nucleotide sugar species, and higher rates of mAb galactosylation, despite a reduced rate of cell growth. The reduction in biomass accumulation allowed cells to redistribute their energy and resources toward mAb synthesis and Fc‐glycosylation. Interestingly, the higher capacity of cells to galactosylate the recombinant product in TGE at 32°C appears not to have been assisted by the upregulation of galactosyltransferases (GalTs), but by the increased expression of N‐acetylglucosaminyltransferase II (GnTII) in this cell line, which facilitated the production of bi‐antennary glycan structures for further processing.
    Type of Medium: Online Resource
    ISSN: 0006-3592 , 1097-0290
    URL: Issue
    URL: Article
    DOI: 10.1002/bit.v115.2
    DOI: 10.1002/bit.26456
    Language: English
    Publisher: Wiley
    Publication Date: 2018
    detail.hit.zdb_id: 1480809-2
    detail.hit.zdb_id: 280318-5
    SSG: 12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 4
    Online Resource
    Online Resource
    Understanding the impact of different bioprocess conditions on monoclonal antibody glycosylation in CHO cell cultures through experimental and computational analyses
    Springer Science and Business Media LLC ; 2015
    In:  BMC Proceedings Vol. 9, No. S9 ( 2015-12)
    Details
    In: BMC Proceedings, Springer Science and Business Media LLC, Vol. 9, No. S9 ( 2015-12)
    Type of Medium: Online Resource
    ISSN: 1753-6561
    URL: Article
    DOI: 10.1186/1753-6561-9-S9-O6
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2015
    detail.hit.zdb_id: 2411867-9
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...