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Livne H, Avital T, Ruppo S, Harazi A, Mitrani-Rosenbaum S, Daya A. Generation and characterization of a novel gne Knockout Model in Zebrafish. Front Cell Dev Biol 2022; 10:976111. [PMID: 36353515 PMCID: PMC9637792 DOI: 10.3389/fcell.2022.976111] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 09/14/2022] [Indexed: 12/04/2022] Open
Abstract
GNE Myopathy is a rare, recessively inherited neuromuscular worldwide disorder, caused by a spectrum of bi-allelic mutations in the human GNE gene. GNE encodes a bi-functional enzyme responsible for the rate-limiting step of sialic acid biosynthesis pathway. However, the process in which GNE mutations lead to the development of a muscle pathology is not clear yet. Cellular and mouse models for GNE Myopathy established to date have not been informative. Further, additional GNE functions in muscle have been hypothesized. In these studies, we aimed to investigate gne functions using zebrafish genetic and transgenic models, and characterized them using macroscopic, microscopic, and molecular approaches. We first established transgenic zebrafish lineages expressing the human GNE cDNA carrying the M743T mutation, driven by the zebrafish gne promoter. These fish developed entirely normally. Then, we generated a gne knocked-out (KO) fish using the CRISPR/Cas9 methodology. These fish died 8–10 days post-fertilization (dpf), but a phenotype appeared less than 24 h before death and included progressive body axis curving, deflation of the swim bladder and decreasing movement and heart rate. However, muscle histology uncovered severe defects, already at 5 dpf, with compromised fiber organization. Sialic acid supplementation did not rescue the larvae from this phenotype nor prolonged their lifespan. To have deeper insights into the potential functions of gne in zebrafish, RNA sequencing was performed at 3 time points (3, 5, and 7 dpf). Genotype clustering was progressive, with only 5 genes differentially expressed in gne KO compared to gne WT siblings at 3 dpf. Enrichment analyses of the primary processes affected by the lack of gne also at 5 and 7 dpf point to the involvement of cell cycle and DNA damage/repair processes in the gne KO zebrafish. Thus, we have established a gne KO zebrafish lineage and obtained new insights into gne functions. This is the only model where GNE can be related to clear muscle defects, thus the only animal model relevant to GNE Myopathy to date. Further elucidation of gne precise mechanism-of-action in these processes could be relevant to GNE Myopathy and allow the identification of novel therapeutic targets.
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Affiliation(s)
- Hagay Livne
- Faculty of Marine Sciences, Ruppin Academic Center, Michmoret, Israel
- Goldyne Savad Institute of Gene Therapy, Hadassah Medical Center, The Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Tom Avital
- Faculty of Marine Sciences, Ruppin Academic Center, Michmoret, Israel
| | - Shmuel Ruppo
- Info-CORE, Bioinformatics Unit of the I-CORE, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Avi Harazi
- Faculty of Marine Sciences, Ruppin Academic Center, Michmoret, Israel
- Goldyne Savad Institute of Gene Therapy, Hadassah Medical Center, The Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Stella Mitrani-Rosenbaum
- Goldyne Savad Institute of Gene Therapy, Hadassah Medical Center, The Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Alon Daya
- Faculty of Marine Sciences, Ruppin Academic Center, Michmoret, Israel
- *Correspondence: Alon Daya,
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Kotidis P, Pappas I, Avraamidou S, Pistikopoulos EN, Kontoravdi C, Papathanasiou MM. DigiGlyc: A hybrid tool for reactive scheduling in cell culture systems. Comput Chem Eng 2021. [DOI: 10.1016/j.compchemeng.2021.107460] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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3
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Dahodwala H, Lee KH. The fickle CHO: a review of the causes, implications, and potential alleviation of the CHO cell line instability problem. Curr Opin Biotechnol 2019; 60:128-137. [DOI: 10.1016/j.copbio.2019.01.011] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Revised: 12/04/2018] [Accepted: 01/21/2019] [Indexed: 02/08/2023]
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4
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Chen X, Liu X, Xiao Z, Liu J, Zhao L, Tan WS, Fan L. Insights into the loss of protein sialylation in an fc-fusion protein-producing CHO cell bioprocess. Appl Microbiol Biotechnol 2019; 103:4753-4765. [DOI: 10.1007/s00253-019-09850-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 04/09/2019] [Accepted: 04/11/2019] [Indexed: 10/26/2022]
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5
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Castilho A, Beihammer G, Pfeiffer C, Göritzer K, Montero‐Morales L, Vavra U, Maresch D, Grünwald‐Gruber C, Altmann F, Steinkellner H, Strasser R. An oligosaccharyltransferase from Leishmania major increases the N-glycan occupancy on recombinant glycoproteins produced in Nicotiana benthamiana. PLANT BIOTECHNOLOGY JOURNAL 2018; 16:1700-1709. [PMID: 29479800 PMCID: PMC6131413 DOI: 10.1111/pbi.12906] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 12/15/2017] [Accepted: 02/06/2018] [Indexed: 05/19/2023]
Abstract
N-glycosylation is critical for recombinant glycoprotein production as it influences the heterogeneity of products and affects their biological function. In most eukaryotes, the oligosaccharyltransferase is the central-protein complex facilitating the N-glycosylation of proteins in the lumen of the endoplasmic reticulum (ER). Not all potential N-glycosylation sites are recognized in vivo and the site occupancy can vary in different expression systems, resulting in underglycosylation of recombinant glycoproteins. To overcome this limitation in plants, we expressed LmSTT3D, a single-subunit oligosaccharyltransferase from the protozoan Leishmania major transiently in Nicotiana benthamiana, a well-established production platform for recombinant proteins. A fluorescent protein-tagged LmSTT3D variant was predominately found in the ER and co-located with plant oligosaccharyltransferase subunits. Co-expression of LmSTT3D with immunoglobulins and other recombinant human glycoproteins resulted in a substantially increased N-glycosylation site occupancy on all N-glycosylation sites except those that were already more than 90% occupied. Our results show that the heterologous expression of LmSTT3D is a versatile tool to increase N-glycosylation efficiency in plants.
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Affiliation(s)
- Alexandra Castilho
- Department of Applied Genetics and Cell BiologyUniversity of Natural Resources and Life SciencesViennaAustria
| | - Gernot Beihammer
- Department of Applied Genetics and Cell BiologyUniversity of Natural Resources and Life SciencesViennaAustria
| | - Christina Pfeiffer
- Department of Applied Genetics and Cell BiologyUniversity of Natural Resources and Life SciencesViennaAustria
| | - Kathrin Göritzer
- Department of Applied Genetics and Cell BiologyUniversity of Natural Resources and Life SciencesViennaAustria
| | - Laura Montero‐Morales
- Department of Applied Genetics and Cell BiologyUniversity of Natural Resources and Life SciencesViennaAustria
| | - Ulrike Vavra
- Department of Applied Genetics and Cell BiologyUniversity of Natural Resources and Life SciencesViennaAustria
| | - Daniel Maresch
- Department of ChemistryUniversity of Natural Resources and Life SciencesViennaAustria
| | | | - Friedrich Altmann
- Department of ChemistryUniversity of Natural Resources and Life SciencesViennaAustria
| | - Herta Steinkellner
- Department of Applied Genetics and Cell BiologyUniversity of Natural Resources and Life SciencesViennaAustria
| | - Richard Strasser
- Department of Applied Genetics and Cell BiologyUniversity of Natural Resources and Life SciencesViennaAustria
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6
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Chen X, Liu J, Liu X, Fan L, Zhao L, Tan WS. Characterization and minimization of sialic acid degradation in an Fc-fusion protein-producing CHO cell bioprocess. Process Biochem 2018. [DOI: 10.1016/j.procbio.2018.08.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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7
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Orellana CA, Marcellin E, Palfreyman RW, Munro TP, Gray PP, Nielsen LK. RNA-Seq Highlights High Clonal Variation in Monoclonal Antibody Producing CHO Cells. Biotechnol J 2018; 13:e1700231. [DOI: 10.1002/biot.201700231] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 12/12/2017] [Indexed: 01/08/2023]
Affiliation(s)
- Camila A. Orellana
- Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland; Brisbane QLD 4072 Australia
| | - Esteban Marcellin
- Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland; Brisbane QLD 4072 Australia
- Metabolomics Australia (Queensland Node), The University of Queensland; Brisbane QLD 4072 Australia
| | - Robin W. Palfreyman
- Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland; Brisbane QLD 4072 Australia
| | - Trent P. Munro
- Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland; Brisbane QLD 4072 Australia
| | - Peter P. Gray
- Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland; Brisbane QLD 4072 Australia
| | - Lars K. Nielsen
- Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland; Brisbane QLD 4072 Australia
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark; 2800 Kgs, Lyngby Denmark
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Karengera E, Robotham A, Kelly J, Durocher Y, De Crescenzo G, Henry O. Concomitant reduction of lactate and ammonia accumulation in fed-batch cultures: Impact on glycoprotein production and quality. Biotechnol Prog 2018; 34:494-504. [DOI: 10.1002/btpr.2607] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Revised: 10/24/2017] [Indexed: 01/15/2023]
Affiliation(s)
- Eric Karengera
- Department of Chemical Engineering; École Polytechnique de Montréal, P.O. Box 6079, succ. Centre-Ville; Montréal Quebec H3C 3A7 Canada
| | - Anna Robotham
- Human Health Therapeutics Portfolio, National Research Council Canada; Ottawa Ontario Canada
| | - John Kelly
- Human Health Therapeutics Portfolio, National Research Council Canada; Ottawa Ontario Canada
| | - Yves Durocher
- Human Health Therapeutics Portfolio, National Research Council Canada; Montréal Quebec Canada
| | - Gregory De Crescenzo
- Department of Chemical Engineering; École Polytechnique de Montréal, P.O. Box 6079, succ. Centre-Ville; Montréal Quebec H3C 3A7 Canada
| | - Olivier Henry
- Department of Chemical Engineering; École Polytechnique de Montréal, P.O. Box 6079, succ. Centre-Ville; Montréal Quebec H3C 3A7 Canada
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9
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Karengera E, Durocher Y, De Crescenzo G, Henry O. Combining metabolic and process engineering strategies to improve recombinant glycoprotein production and quality. Appl Microbiol Biotechnol 2017; 101:7837-7851. [PMID: 28924963 DOI: 10.1007/s00253-017-8513-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Revised: 08/15/2017] [Accepted: 09/02/2017] [Indexed: 11/28/2022]
Abstract
Increasing recombinant protein production while ensuring a high and consistent protein quality remains a challenge in mammalian cell culture process development. In this work, we combined a nutrient substitution approach with a metabolic engineering strategy that improves glucose utilization efficiency. This combination allowed us to tackle both lactate and ammonia accumulation and investigate on potential synergistic effects on protein production and quality. To this end, HEK293 cells overexpressing the pyruvate yeast carboxylase (PYC2) and their parental cells, both stably producing the therapeutic glycoprotein interferon α2b (IFNα2b), were cultured in media deprived of glutamine but containing chosen substitutes. Among the tested substitutes, pyruvate led to the best improvement in growth (integral of viable cell density) for both cell lines in batch cultures, whereas the culture of PYC2 cells without neither glutamine nor any substitute displayed surprisingly enhanced IFNα2b production. The drastic reduction in both lactate and ammonia in the cultures translated into extended high viability conditions and an increase in recombinant protein titer by up to 47% for the parental cells and the PYC2 cells. Product characterization performed by surface plasmon resonance biosensing using Sambucus nigra (SNA) lectin revealed that the increase in yield was however accompanied by a reduction in the degree of sialylation of the product. Supplementing cultures with glycosylation precursors and a cofactor were effective at counterbalancing the lack of glutamine and allowed improvement in IFNα2b quality as evaluated by lectin affinity. Our study provides a strategy to reconcile protein productivity and quality and highlights the advantages of PYC2-overexpressing cells in glutamine-free conditions.
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Affiliation(s)
- Eric Karengera
- Department of Chemical Engineering, École Polytechnique de Montréal, P.O. Box 6079, Succ. Centre-Ville, Montreal, QC, H3C 3A7, Canada
| | - Yves Durocher
- Human Health Therapeutics Portfolio, National Research Council Canada, Montreal, Canada
| | - Gregory De Crescenzo
- Department of Chemical Engineering, École Polytechnique de Montréal, P.O. Box 6079, Succ. Centre-Ville, Montreal, QC, H3C 3A7, Canada
| | - Olivier Henry
- Department of Chemical Engineering, École Polytechnique de Montréal, P.O. Box 6079, Succ. Centre-Ville, Montreal, QC, H3C 3A7, Canada.
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10
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Cha HM, Lim JH, Yeon JH, Hwang JM, Kim DI. Co-overexpression of Mgat1 and Mgat4 in CHO cells for production of highly sialylated albumin-erythropoietin. Enzyme Microb Technol 2017; 103:53-58. [PMID: 28554385 DOI: 10.1016/j.enzmictec.2017.04.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Revised: 03/30/2017] [Accepted: 04/28/2017] [Indexed: 12/22/2022]
Abstract
Terminal sialic acids on N-glycan of recombinant human erythropoietin are very important for in vivo half-life, as this glycoprotein has three N-glycosylation sites. N-acetylglucosaminyltransferases I, II, IV, and V (i.e. Mgat1, Mgat2, Mgat4, and Mgat5) catalyze the formation of a glycan antennary structure. These enzymes display different reaction kinetics for a common substrate and generally show low expression in Chinese hamster ovary (CHO) cells. Therefore, genetic control of Mgat expression is an effective method to increase sialic acid contents by enhancing glycan antennarity. To produce highly sialylated albumin-erythropoietin (Alb-EPO), we co-overexpressed the Mgat1 and Mgat4 genes in CHO cells and determined the optimal ratio of Mgat1:Mgat4 gene expression. All transfected cell lines showed increased gene expression of Mgat4, including Mgat1 overexpressing cell line. Sialic acid content of Alb-EPO was highest in co-transfected cells with excess Mgat4 gene, and these cells showed a higher tri- and tetra-antennary structure than control cells. Based on these results, we suggest that co-transfection of the Mgat1 and Mgat4 genes at a ratio of 2:8 is optimal for extension of antennary structures. Also, regulation of Mgat gene expression in the glycan biosynthesis pathway can be a novel approach to increase the terminal sialic acids of N-glycans.
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Affiliation(s)
- Hyun-Myoung Cha
- Department of Biological Engineering, Inha University, Incheon 22212, Republic of Korea
| | - Jin-Hyuk Lim
- Department of Biological Engineering, Inha University, Incheon 22212, Republic of Korea
| | - Jung-Heum Yeon
- Department of Biological Engineering, Inha University, Incheon 22212, Republic of Korea
| | - Jeong-Min Hwang
- Department of Biological Engineering, Inha University, Incheon 22212, Republic of Korea
| | - Dong-Il Kim
- Department of Biological Engineering, Inha University, Incheon 22212, Republic of Korea.
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11
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Brühlmann D, Muhr A, Parker R, Vuillemin T, Bucsella B, Kalman F, Torre S, La Neve F, Lembo A, Haas T, Sauer M, Souquet J, Broly H, Hemberger J, Jordan M. Cell culture media supplemented with raffinose reproducibly enhances high mannose glycan formation. J Biotechnol 2017; 252:32-42. [PMID: 28465212 DOI: 10.1016/j.jbiotec.2017.04.026] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Revised: 04/06/2017] [Accepted: 04/21/2017] [Indexed: 12/21/2022]
Abstract
Glycosylation plays a pivotal role in pharmacokinetics and protein physiochemical characteristics. In particular, effector functions including antibody-dependent cell-mediated cytotoxicity (ADCC) can be desired, and it has been described that high-mannose species exhibited enhanced ADCC. In this work we present the trisaccharide raffinose as a novel cell culture medium supplement to promote high mannose N-glycans in fed-batch cultures, which is sought after in the development of biosimilars to match the quality profile of the reference medicinal product (RMP) also. Up to six-fold increases of high mannose species were observed with increasing raffinose concentrations in the medium of shaken 96-deepwell plates and shake tubes when culturing two different CHO cell lines in two different media. The findings were confirmed in a pH-, oxygen- and CO2-controlled environment in lab-scale 3.5-L bioreactors. To circumvent detrimental effects on cell growth and productivity at high raffinose concentrations, the media osmolality was adjusted to reach the same value independently of the supplement concentration. Interestingly, raffinose predominantly enhanced mannose 5 glycans, and to a considerably smaller degree, mannose 6. While the underlying mechanism is still not fully understood, minor effects on the nucleotide sugar levels have been observed and transcriptomics analysis revealed that raffinose supplementation altered the expression levels of a number of glycosylation related genes. Among many genes, galactosyltransferase was downregulated and sialyltransferase upregulated. Our results highlight the potential of cell culture medium supplementation to modulate product quality.
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Affiliation(s)
- David Brühlmann
- Merck Biopharma, Biotech Process Sciences, Corsier-sur-Vevey, Switzerland; Department of Biotechnology and Biophysics, Biozentrum, Julius-Maximilians-Universität Würzburg, Germany
| | - Anais Muhr
- Merck Biopharma, Biotech Process Sciences, Corsier-sur-Vevey, Switzerland
| | - Rebecca Parker
- Merck Biopharma, Biotech Process Sciences, Corsier-sur-Vevey, Switzerland; Institute for Biochemical Engineering and Analytics, University of Applied Sciences Giessen, Germany
| | - Thomas Vuillemin
- Merck Biopharma, Biotech Process Sciences, Corsier-sur-Vevey, Switzerland
| | - Blanka Bucsella
- HES-SO Valais-Wallis, Institute of Life Technologies, Sion, Switzerland
| | - Franka Kalman
- HES-SO Valais-Wallis, Institute of Life Technologies, Sion, Switzerland
| | - Serena Torre
- A. Marxer - RBM S.p.A., a Company part of Merck Group, Next Generation Technologies, Colleretto Giacosa, Italy; Molecular Biotechnologies Center, MBC, University of Turin, Italy
| | - Fabio La Neve
- A. Marxer - RBM S.p.A., a Company part of Merck Group, Next Generation Technologies, Colleretto Giacosa, Italy
| | - Antonio Lembo
- A. Marxer - RBM S.p.A., a Company part of Merck Group, Next Generation Technologies, Colleretto Giacosa, Italy
| | - Tobias Haas
- A. Marxer - RBM S.p.A., a Company part of Merck Group, Next Generation Technologies, Colleretto Giacosa, Italy
| | - Markus Sauer
- Department of Biotechnology and Biophysics, Biozentrum, Julius-Maximilians-Universität Würzburg, Germany
| | - Jonathan Souquet
- Merck Biopharma, Biotech Process Sciences, Corsier-sur-Vevey, Switzerland
| | - Hervé Broly
- Merck Biopharma, Biotech Process Sciences, Corsier-sur-Vevey, Switzerland
| | - Jürgen Hemberger
- Institute for Biochemical Engineering and Analytics, University of Applied Sciences Giessen, Germany
| | - Martin Jordan
- Merck Biopharma, Biotech Process Sciences, Corsier-sur-Vevey, Switzerland.
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12
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Lee JH, Jeong YR, Kim YG, Lee GM. Understanding of decreased sialylation of Fc-fusion protein in hyperosmotic recombinant Chinese hamster ovary cell culture: N-glycosylation gene expression and N-linked glycan antennary profile. Biotechnol Bioeng 2017; 114:1721-1732. [PMID: 28266015 DOI: 10.1002/bit.26284] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2016] [Revised: 02/16/2017] [Accepted: 02/28/2017] [Indexed: 01/14/2023]
Abstract
To understand the effects of hyperosmolality on protein glycosylation, recombinant Chinese hamster ovary (rCHO) cells producing the Fc-fusion protein were cultivated in hyperosmolar medium resulting from adding NaCl (415 mOsm/kg). The hyperosmotic culture showed increased specific Fc-fusion protein productivity (qFc ) but a decreased proportion of acidic isoforms and sialic acid content of the Fc-fusion protein. The intracellular and extracellular sialidase activities in the hyperosmotic cultures were similar to those in the control culture (314 mOsm/kg), indicating that reduced sialylation of Fc-fusion protein at hyperosmolality was not due to elevated sialidase activity. Expression of 52 N-glycosylation-related genes was assessed by the NanoString nCounter system, which provides a direct digital readout using custom-designed color-coded probes. After 3 days of hyperosmotic culture, nine genes (ugp, slc35a3, slc35d2, gcs1, manea, mgat2, mgat5b, b4galt3, and b4galt4) were differentially expressed over 1.5-fold of the control, and all these genes were down-regulated. N-linked glycan analysis by anion exchange and hydrophilic interaction HPLC showed that the proportion of highly sialylated (di-, tri-, tetra-) and tetra-antennary N-linked glycans was significantly decreased upon hyperosmotic culture. Addition of betaine, an osmoprotectant, to the hyperosmotic culture significantly increased the proportion of highly sialylated and tetra-antennary N-linked glycans (P ≤ 0.05), while it increased the expression of the N-glycan branching/antennary genes (mgat2 and mgat4b). Thus, decreased expression of the genes with roles in the N-glycan biosynthesis pathway correlated with reduced sialic acid content of Fc-fusion protein caused by hyperosmolar conditions. Taken together, the results obtained in this study provide a better understanding of the detrimental effects of hyperosmolality on N-glycosylation, especially sialylation, in rCHO cells. Biotechnol. Bioeng. 2017;114: 1721-1732. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Jong Hyun Lee
- Department of Biological Sciences, KAIST, 335 Gwahak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea
| | - Yeong Ran Jeong
- Department of Biological Sciences, KAIST, 335 Gwahak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea
| | - Yeon-Gu Kim
- Biotechnology Process Engineering Center, KRIBB, Ochang-eup, Cheongwon-gu, Cheongju, Republic of Korea.,Department of Bioprocess Engineering, Korea University of Science and Technology (UST), Gajeong-ro, Yuseong-gu, Daejeon, Republic of Korea
| | - Gyun Min Lee
- Department of Biological Sciences, KAIST, 335 Gwahak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea
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Qian Y, Lewis AM, Sidnam SM, Bergeron A, Abu-Absi NR, Vaidyanathan N, Deresienski A, Qian NX, Borys MC, Li ZJ. LongR3 enhances Fc-fusion protein N-linked glycosylation while improving protein productivity in an industrial CHO cell line. Process Biochem 2017. [DOI: 10.1016/j.procbio.2016.11.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Dahodwala H, Sharfstein ST. The 'Omics Revolution in CHO Biology: Roadmap to Improved CHO Productivity. Methods Mol Biol 2017; 1603:153-168. [PMID: 28493129 DOI: 10.1007/978-1-4939-6972-2_10] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Increased understanding of Chinese hamster ovary (CHO) cell physiology has been ushered in upon availability of the parental CHO-K1 cell line genome. Free and openly accessible sequence information has complemented transcriptomic and proteomic studies. The previous decade has also seen an increase in sensitivity and accuracy of proteomic methods due to technology development. In this genomic era, high-throughput screening methods, sophisticated informatic tools, and models continually drive major innovations in cell line development and process engineering. This review describes the various achievements in 'omics techniques and their application to improve recombinant protein expression from CHO cell lines.
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Affiliation(s)
- Hussain Dahodwala
- Vaccine production program (VPP), VRC/NIAID/NIH, Gaithersburg, MD, 20878, USA
- SUNY Polytechnic Institute, 257 Fuller Road, Albany, NY, 12203, USA
| | - Susan T Sharfstein
- Vaccine production program (VPP), VRC/NIAID/NIH, Gaithersburg, MD, 20878, USA.
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Saldova R, Kilcoyne M, Stöckmann H, Millán Martín S, Lewis AM, Tuite CME, Gerlach JQ, Le Berre M, Borys MC, Li ZJ, Abu-Absi NR, Leister K, Joshi L, Rudd PM. Advances in analytical methodologies to guide bioprocess engineering for bio-therapeutics. Methods 2016; 116:63-83. [PMID: 27832969 DOI: 10.1016/j.ymeth.2016.11.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Revised: 10/27/2016] [Accepted: 11/03/2016] [Indexed: 12/15/2022] Open
Abstract
This study was performed to monitor the glycoform distribution of a recombinant antibody fusion protein expressed in CHO cells over the course of fed-batch bioreactor runs using high-throughput methods to accurately determine the glycosylation status of the cell culture and its product. Three different bioreactors running similar conditions were analysed at the same five time-points using the advanced methods described here. N-glycans from cell and secreted glycoproteins from CHO cells were analysed by HILIC-UPLC and MS, and the total glycosylation (both N- and O-linked glycans) secreted from the CHO cells were analysed by lectin microarrays. Cell glycoproteins contained mostly high mannose type N-linked glycans with some complex glycans; sialic acid was α-(2,3)-linked, galactose β-(1,4)-linked, with core fucose. Glycans attached to secreted glycoproteins were mostly complex with sialic acid α-(2,3)-linked, galactose β-(1,4)-linked, with mostly core fucose. There were no significant differences noted among the bioreactors in either the cell pellets or supernatants using the HILIC-UPLC method and only minor differences at the early time-points of days 1 and 3 by the lectin microarray method. In comparing different time-points, significant decreases in sialylation and branching with time were observed for glycans attached to both cell and secreted glycoproteins. Additionally, there was a significant decrease over time in high mannose type N-glycans from the cell glycoproteins. A combination of the complementary methods HILIC-UPLC and lectin microarrays could provide a powerful and rapid HTP profiling tool capable of yielding qualitative and quantitative data for a defined biopharmaceutical process, which would allow valuable near 'real-time' monitoring of the biopharmaceutical product.
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Affiliation(s)
- Radka Saldova
- NIBRT GlycoScience Group, The National Institute for Bioprocessing Research and Training, Fosters Avenue, Mount Merrion, Blackrock, Dublin 4, Ireland.
| | - Michelle Kilcoyne
- Glycoscience Group, National Centre for Biomedical Engineering Science, National University of Ireland Galway, Galway, Ireland; Microbiology, School of Natural Sciences, National University of Ireland Galway, Galway, Ireland.
| | - Henning Stöckmann
- NIBRT GlycoScience Group, The National Institute for Bioprocessing Research and Training, Fosters Avenue, Mount Merrion, Blackrock, Dublin 4, Ireland.
| | - Silvia Millán Martín
- NIBRT GlycoScience Group, The National Institute for Bioprocessing Research and Training, Fosters Avenue, Mount Merrion, Blackrock, Dublin 4, Ireland.
| | - Amanda M Lewis
- Bristol-Myers Squibb, BMS, Biologics Development, 38 Jackson Road, Devens, MA 01434, USA.
| | - Catherine M E Tuite
- Glycoscience Group, National Centre for Biomedical Engineering Science, National University of Ireland Galway, Galway, Ireland.
| | - Jared Q Gerlach
- Glycoscience Group, National Centre for Biomedical Engineering Science, National University of Ireland Galway, Galway, Ireland; Regenerative Medicine Institute, National Centre for Biomedical Engineering Science, National University of Ireland Galway, Galway, Ireland.
| | - Marie Le Berre
- Glycoscience Group, National Centre for Biomedical Engineering Science, National University of Ireland Galway, Galway, Ireland.
| | - Michael C Borys
- Bristol-Myers Squibb, BMS, Biologics Development, 38 Jackson Road, Devens, MA 01434, USA.
| | - Zheng Jian Li
- Bristol-Myers Squibb, BMS, Biologics Development, 38 Jackson Road, Devens, MA 01434, USA.
| | - Nicholas R Abu-Absi
- Bristol-Myers Squibb, BMS, Biologics Development, 38 Jackson Road, Devens, MA 01434, USA.
| | - Kirk Leister
- Bristol-Myers Squibb, BMS, Biologics Development, 38 Jackson Road, Devens, MA 01434, USA.
| | - Lokesh Joshi
- Glycoscience Group, National Centre for Biomedical Engineering Science, National University of Ireland Galway, Galway, Ireland.
| | - Pauline M Rudd
- NIBRT GlycoScience Group, The National Institute for Bioprocessing Research and Training, Fosters Avenue, Mount Merrion, Blackrock, Dublin 4, Ireland.
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16
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Lewis AM, Croughan WD, Aranibar N, Lee AG, Warrack B, Abu-Absi NR, Patel R, Drew B, Borys MC, Reily MD, Li ZJ. Understanding and Controlling Sialylation in a CHO Fc-Fusion Process. PLoS One 2016; 11:e0157111. [PMID: 27310468 PMCID: PMC4911072 DOI: 10.1371/journal.pone.0157111] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2016] [Accepted: 05/24/2016] [Indexed: 12/13/2022] Open
Abstract
A Chinese hamster ovary (CHO) bioprocess, where the product is a sialylated Fc-fusion protein, was operated at pilot and manufacturing scale and significant variation of sialylation level was observed. In order to more tightly control glycosylation profiles, we sought to identify the cause of variability. Untargeted metabolomics and transcriptomics methods were applied to select samples from the large scale runs. Lower sialylation was correlated with elevated mannose levels, a shift in glucose metabolism, and increased oxidative stress response. Using a 5-L scale model operated with a reduced dissolved oxygen set point, we were able to reproduce the phenotypic profiles observed at manufacturing scale including lower sialylation, higher lactate and lower ammonia levels. Targeted transcriptomics and metabolomics confirmed that reduced oxygen levels resulted in increased mannose levels, a shift towards glycolysis, and increased oxidative stress response similar to the manufacturing scale. Finally, we propose a biological mechanism linking large scale operation and sialylation variation. Oxidative stress results from gas transfer limitations at large scale and the presence of oxygen dead-zones inducing upregulation of glycolysis and mannose biosynthesis, and downregulation of hexosamine biosynthesis and acetyl-CoA formation. The lower flux through the hexosamine pathway and reduced intracellular pools of acetyl-CoA led to reduced formation of N-acetylglucosamine and N-acetylneuraminic acid, both key building blocks of N-glycan structures. This study reports for the first time a link between oxidative stress and mammalian protein sialyation. In this study, process, analytical, metabolomic, and transcriptomic data at manufacturing, pilot, and laboratory scales were taken together to develop a systems level understanding of the process and identify oxygen limitation as the root cause of glycosylation variability.
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Affiliation(s)
- Amanda M. Lewis
- Biologics Development, Global Manufacturing and Supply, Bristol-Myers Squibb Company, Devens, MA, United States of America
- * E-mail:
| | - William D. Croughan
- Biologics Development, Global Manufacturing and Supply, Bristol-Myers Squibb Company, Devens, MA, United States of America
| | - Nelly Aranibar
- Research and Development, Bristol-Myers Squibb Company, Princeton, NJ, United States of America
| | - Alison G. Lee
- Biologics Development, Global Manufacturing and Supply, Bristol-Myers Squibb Company, Devens, MA, United States of America
| | - Bethanne Warrack
- Research and Development, Bristol-Myers Squibb Company, Princeton, NJ, United States of America
| | - Nicholas R. Abu-Absi
- Biologics Development, Global Manufacturing and Supply, Bristol-Myers Squibb Company, Devens, MA, United States of America
| | - Rutva Patel
- Biologics Development, Global Manufacturing and Supply, Bristol-Myers Squibb Company, Devens, MA, United States of America
| | - Barry Drew
- Biologics Development, Global Manufacturing and Supply, Bristol-Myers Squibb Company, Devens, MA, United States of America
| | - Michael C. Borys
- Biologics Development, Global Manufacturing and Supply, Bristol-Myers Squibb Company, Devens, MA, United States of America
| | - Michael D. Reily
- Research and Development, Bristol-Myers Squibb Company, Princeton, NJ, United States of America
| | - Zheng Jian Li
- Biologics Development, Global Manufacturing and Supply, Bristol-Myers Squibb Company, Devens, MA, United States of America
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17
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Sha S, Agarabi C, Brorson K, Lee DY, Yoon S. N-Glycosylation Design and Control of Therapeutic Monoclonal Antibodies. Trends Biotechnol 2016; 34:835-846. [PMID: 27016033 DOI: 10.1016/j.tibtech.2016.02.013] [Citation(s) in RCA: 99] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Revised: 02/20/2016] [Accepted: 02/24/2016] [Indexed: 12/31/2022]
Abstract
The N-linked glycan profiles on recombinant monoclonal antibody therapeutics significantly affect antibody biological functions and are largely determined by host cell genotypes and culture conditions. A key step in bioprocess development for monoclonal antibodies (mAbs) involves optimization and control of N-glycan profiles. With pressure from pricing and biosimilars looming, more efficient and effective approaches are sought in the field of glycoengineering. Metabolic studies and mathematical modeling are two such approaches that optimize bioprocesses by better understanding and predicting glycosylation. In this review, we summarize a group of strategies currently used for glycan profile modulation and control. Metabolic analysis and mathematical modeling are then explored with an emphasis on how these two techniques can be utilized to advance glycoengineering.
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Affiliation(s)
- Sha Sha
- Biomedical Engineering and Biotechnology, University of Massachusetts Lowell, Lowell, MA 01850, USA
| | - Cyrus Agarabi
- Division of Biotechnology Review and Research II, Office of Biotechnology Products, OPQ, CDER, FDA, Silver Spring, MD, USA
| | - Kurt Brorson
- Division of Biotechnology Review and Research II, Office of Biotechnology Products, OPQ, CDER, FDA, Silver Spring, MD, USA
| | - Dong-Yup Lee
- Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive, Singapore 117585, Singapore
| | - Seongkyu Yoon
- Biomedical Engineering and Biotechnology, University of Massachusetts Lowell, Lowell, MA 01850, USA.
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18
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Markely LRA, Cheung L, Choi YJ, Ryll T, Estes S, Prajapati S, Turyan I, Frenkel R, Sosic Z, Lambropoulos J, Tescione L, Ryll T, Berman M. A high-throughput capillary isoelectric focusing immunoassay for fingerprinting protein sialylation. Biotechnol Prog 2015; 32:235-41. [DOI: 10.1002/btpr.2206] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Revised: 09/15/2015] [Indexed: 12/14/2022]
Affiliation(s)
- Lam Raga Anggara Markely
- Cell Culture Development-High-Throughput Analytical Group; Biogen, 125 Broadway Cambridge MA 02142
| | - Lila Cheung
- Cell Culture Development-High-Throughput Analytical Group; Biogen, 125 Broadway Cambridge MA 02142
| | - Young Jun Choi
- Cell Culture Development-High-Throughput Analytical Group; Biogen, 125 Broadway Cambridge MA 02142
| | - Thomas Ryll
- Cell Culture Development-High-Throughput Analytical Group; Biogen, 125 Broadway Cambridge MA 02142
| | - Scott Estes
- Cell Culture Development-High-Throughput Analytical Group; Biogen, 125 Broadway Cambridge MA 02142
| | - Shashi Prajapati
- Cell Culture Development-High-Throughput Analytical Group; Biogen, 125 Broadway Cambridge MA 02142
| | - Iva Turyan
- Analytical Development - High-Throughput Analytical Group; Biogen, 125 Broadway Cambridge MA 02142
| | - Ruth Frenkel
- Analytical Development - High-Throughput Analytical Group; Biogen, 125 Broadway Cambridge MA 02142
| | - Zoran Sosic
- Analytical Development - High-Throughput Analytical Group; Biogen, 125 Broadway Cambridge MA 02142
| | | | - Lia Tescione
- Cell Culture Development; Biogen, 125 Broadway Cambridge MA 02142
| | - Thomas Ryll
- Cell Culture Development; Biogen, 125 Broadway Cambridge MA 02142
| | - Melissa Berman
- Biomolecular and Small Molecule Science; Biogen, 125 Broadway Cambridge MA 02142
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19
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Tuning a MAb glycan profile in cell culture: Supplementing N-acetylglucosamine to favour G0 glycans without compromising productivity and cell growth. J Biotechnol 2015; 214:105-12. [PMID: 26387447 DOI: 10.1016/j.jbiotec.2015.09.014] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Revised: 07/28/2015] [Accepted: 09/15/2015] [Indexed: 11/23/2022]
Abstract
Glycosylation is a critical quality attribute of many therapeutic proteins, particularly monoclonal antibodies (MAbs). Nucleotide-sugar precursors supplemented to growth medium to affect the substrate supply chain of glycosylation has yielded promising but varied results for affecting glycosylation. Glucosamine (GlcN), a precursor for N-acetylglucosamine (GlcNAc), is a major component of mammalian glycans. The supplementation of GlcN to CHO cells stably-expressing a chimeric heavy-chain monoclonal antibody, EG2-hFc, reduces the complexity of glycans to favour G0 glycoforms, while also negatively impacting cell growth. Although several researchers have examined the supplementation of glucosamine, no clear explanation of its impact on cell growth has been forthcoming. In this work, the glucosamine metabolism is examined. We identified the acetylation of GlcN to produce GlcNAc to be the most likely cause for the negative impact on growth due to the depletion of intracellular acetyl-CoA pools in the cytosol. By supplementing GlcNAc in lieu of GlcN to CHO cells producing EG2-hFc, we achieve the same shift in glycan complexity with marginal impacts on the cell growth and protein production.
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20
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Fan Y, Jimenez Del Val I, Müller C, Lund AM, Sen JW, Rasmussen SK, Kontoravdi C, Baycin-Hizal D, Betenbaugh MJ, Weilguny D, Andersen MR. A multi-pronged investigation into the effect of glucose starvation and culture duration on fed-batch CHO cell culture. Biotechnol Bioeng 2015; 112:2172-84. [DOI: 10.1002/bit.25620] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Revised: 03/01/2015] [Accepted: 04/07/2015] [Indexed: 12/19/2022]
Affiliation(s)
- Yuzhou Fan
- Network Engineering of Eukaryotic Cell Factories; Department of Systems Biology; Technical University of Denmark; Building 223; 2800 Kgs. Lyngby Denmark
- Symphogen A/S; Pederstrupvej; 93, 2750 Ballerup Denmark
| | - Ioscani Jimenez Del Val
- Center for Process Systems Engineering; Department of Chemical Engineering; Imperial College London South Kensington Campus London SW7 2AZ UK
| | | | - Anne Mathilde Lund
- Network Engineering of Eukaryotic Cell Factories; Department of Systems Biology; Technical University of Denmark; Building 223; 2800 Kgs. Lyngby Denmark
| | | | | | - Cleo Kontoravdi
- Center for Process Systems Engineering; Department of Chemical Engineering; Imperial College London South Kensington Campus London SW7 2AZ UK
| | - Deniz Baycin-Hizal
- Department of Chemical and Biomolecular Engineering; Johns Hopkins University; Baltimore Maryland 21218
| | - Michael J. Betenbaugh
- Department of Chemical and Biomolecular Engineering; Johns Hopkins University; Baltimore Maryland 21218
| | | | - Mikael Rørdam Andersen
- Network Engineering of Eukaryotic Cell Factories; Department of Systems Biology; Technical University of Denmark; Building 223; 2800 Kgs. Lyngby Denmark
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21
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O'Callaghan PM, Berthelot ME, Young RJ, Graham JW, Racher AJ, Aldana D. Diversity in host clone performance within a Chinese hamster ovary cell line. Biotechnol Prog 2015; 31:1187-200. [DOI: 10.1002/btpr.2097] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Revised: 03/24/2015] [Indexed: 12/13/2022]
Affiliation(s)
| | - Maud E. Berthelot
- Lonza Biologics Plc, New Expression Technologies Group; Cambridge CB21 6GS U.K
| | - Robert J. Young
- Lonza Biologics Plc, New Expression Technologies Group; Cambridge CB21 6GS U.K
| | | | - Andrew J. Racher
- Process Development Sciences; Lonza Biologics Plc; Slough SL1 4DX U.K
| | - Dulce Aldana
- Process Analytics; Lonza Biologics Plc; Slough SL1 4DX U.K
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22
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Zhang X, Tang H, Sun YT, Liu X, Tan WS, Fan L. Elucidating the effects of arginine and lysine on a monoclonal antibody C-terminal lysine variation in CHO cell cultures. Appl Microbiol Biotechnol 2015; 99:6643-52. [DOI: 10.1007/s00253-015-6617-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Revised: 04/11/2015] [Accepted: 04/15/2015] [Indexed: 11/24/2022]
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23
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Harvey DJ. Analysis of carbohydrates and glycoconjugates by matrix-assisted laser desorption/ionization mass spectrometry: an update for 2009-2010. MASS SPECTROMETRY REVIEWS 2015; 34:268-422. [PMID: 24863367 PMCID: PMC7168572 DOI: 10.1002/mas.21411] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Revised: 07/16/2013] [Accepted: 07/16/2013] [Indexed: 05/07/2023]
Abstract
This review is the sixth update of the original article published in 1999 on the application of MALDI mass spectrometry to the analysis of carbohydrates and glycoconjugates and brings coverage of the literature to the end of 2010. General aspects such as theory of the MALDI process, matrices, derivatization, MALDI imaging, arrays and fragmentation are covered in the first part of the review and applications to various structural typed constitutes the remainder. The main groups of compound that are discussed in this section are oligo and polysaccharides, glycoproteins, glycolipids, glycosides and biopharmaceuticals. Many of these applications are presented in tabular form. Also discussed are medical and industrial applications of the technique, studies of enzyme reactions and applications to chemical synthesis.
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Affiliation(s)
- David J. Harvey
- Department of BiochemistryOxford Glycobiology InstituteUniversity of OxfordOxfordOX1 3QUUK
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24
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Lin N, Mascarenhas J, Sealover NR, George HJ, Brooks J, Kayser KJ, Gau B, Yasa I, Azadi P, Archer-Hartmann S. Chinese hamster ovary (CHO) host cell engineering to increase sialylation of recombinant therapeutic proteins by modulating sialyltransferase expression. Biotechnol Prog 2015; 31:334-46. [PMID: 25641927 DOI: 10.1002/btpr.2038] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Revised: 09/26/2014] [Indexed: 12/12/2022]
Abstract
N-Glycans of human proteins possess both α2,6- and α2,3-linked terminal sialic acid (SA). Recombinant glycoproteins produced in Chinese hamster overy (CHO) only have α2,3-linkage due to the absence of α2,6-sialyltransferase (St6gal1) expression. The Chinese hamster ST6GAL1 was successfully overexpressed using a plasmid expression vector in three recombinant immunoglobulin G (IgG)-producing CHO cell lines. The stably transfected cell lines were enriched for ST6GAL1 overexpression using FITC-Sambucus nigra (SNA) lectin that preferentially binds α2,6-linked SA. The presence of α2,6-linked SA was confirmed using a novel LTQ Linear Ion Trap Mass Spectrometry (LTQ MS) method including MSn fragmentation in the enriched ST6GAL1 Clone 27. Furthermore, the total SA (mol/mol) in IgG produced by the enriched ST6GAL1 Clone 27 increased by 2-fold compared to the control. For host cell engineering, the CHOZN(®) GS host cell line was transfected and enriched for ST6GAL1 overexpression. Single-cell clones were derived from the enriched population and selected based on FITC-SNA staining and St6gal1 expression. Two clones ("ST6GAL1 OE Clone 31 and 32") were confirmed for the presence of α2,6-linked SA in total host cell protein extracts. ST6GAL1 OE Clone 32 was subsequently used to express SAFC human IgG1. The recombinant IgG expressed in this host cell line was confirmed to have α2,6-linked SA and increased total SA content. In conclusion, overexpression of St6gal1 is sufficient to produce recombinant proteins with increased sialylation and more human-like glycoprofiles without combinatorial engineering of other sialylation pathway genes. This work represents our ongoing effort of glycoengineering in CHO host cell lines for the development of "bio-better" protein therapeutics and cell culture vaccine production.
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Affiliation(s)
- Nan Lin
- Cell Sciences and Development, SAFC/Sigma-Aldrich, 2909 Laclede Avenue, Saint Louis, MO, 63103
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25
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Fan Y, Jimenez Del Val I, Müller C, Wagtberg Sen J, Rasmussen SK, Kontoravdi C, Weilguny D, Andersen MR. Amino acid and glucose metabolism in fed-batch CHO cell culture affects antibody production and glycosylation. Biotechnol Bioeng 2014; 112:521-35. [DOI: 10.1002/bit.25450] [Citation(s) in RCA: 128] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Revised: 08/12/2014] [Accepted: 09/05/2014] [Indexed: 12/12/2022]
Affiliation(s)
- Yuzhou Fan
- Network Engineering of Eukaryotic Cell Factories; Department of Systems Biology; Technical University of Denmark; Building 223 2800 Kgs Lyngby Denmark
- Symphogen A/S; Pederstrupvej 93; 2750 Ballerup Denmark
| | - Ioscani Jimenez Del Val
- Center for Process Systems Engineering; Department of Chemical Engineering; Imperial College London; London UK
| | | | | | | | - Cleo Kontoravdi
- Center for Process Systems Engineering; Department of Chemical Engineering; Imperial College London; London UK
| | | | - Mikael Rørdam Andersen
- Network Engineering of Eukaryotic Cell Factories; Department of Systems Biology; Technical University of Denmark; Building 223 2800 Kgs Lyngby Denmark
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26
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Farrell A, McLoughlin N, Milne JJ, Marison IW, Bones J. Application of Multi-Omics Techniques for Bioprocess Design and Optimization in Chinese Hamster Ovary Cells. J Proteome Res 2014; 13:3144-59. [DOI: 10.1021/pr500219b] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Amy Farrell
- Characterisation
and Comparability Laboratory, NIBRT − The National Institute for Bioprocessing Research and Training, Foster Avenue, Mount Merrion, Blackrock, Co. Dublin, Ireland
| | - Niaobh McLoughlin
- Characterisation
and Comparability Laboratory, NIBRT − The National Institute for Bioprocessing Research and Training, Foster Avenue, Mount Merrion, Blackrock, Co. Dublin, Ireland
| | - John J. Milne
- Characterisation
and Comparability Laboratory, NIBRT − The National Institute for Bioprocessing Research and Training, Foster Avenue, Mount Merrion, Blackrock, Co. Dublin, Ireland
| | - Ian W. Marison
- Laboratory
of Integrated Bioprocessing, Dublin City University, Glasnevin, Dublin 9, Ireland
| | - Jonathan Bones
- Characterisation
and Comparability Laboratory, NIBRT − The National Institute for Bioprocessing Research and Training, Foster Avenue, Mount Merrion, Blackrock, Co. Dublin, Ireland
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27
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Jedrzejewski PM, del Val IJ, Constantinou A, Dell A, Haslam SM, Polizzi KM, Kontoravdi C. Towards controlling the glycoform: a model framework linking extracellular metabolites to antibody glycosylation. Int J Mol Sci 2014; 15:4492-522. [PMID: 24637934 PMCID: PMC3975410 DOI: 10.3390/ijms15034492] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2013] [Revised: 02/07/2014] [Accepted: 02/21/2014] [Indexed: 01/23/2023] Open
Abstract
Glycoproteins represent the largest group of the growing number of biologically-derived medicines. The associated glycan structures and their distribution are known to have a large impact on pharmacokinetics. A modelling framework was developed to provide a link from the extracellular environment and its effect on intracellular metabolites to the distribution of glycans on the constant region of an antibody product. The main focus of this work is the mechanistic in silico reconstruction of the nucleotide sugar donor (NSD) metabolic network by means of 34 species mass balances and the saturation kinetics rates of the 60 metabolic reactions involved. NSDs are the co-substrates of the glycosylation process in the Golgi apparatus and their simulated dynamic intracellular concentration profiles were linked to an existing model describing the distribution of N-linked glycan structures of the antibody constant region. The modelling framework also describes the growth dynamics of the cell population by means of modified Monod kinetics. Simulation results match well to experimental data from a murine hybridoma cell line. The result is a modelling platform which is able to describe the product glycoform based on extracellular conditions. It represents a first step towards the in silico prediction of the glycoform of a biotherapeutic and provides a platform for the optimisation of bioprocess conditions with respect to product quality.
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Affiliation(s)
- Philip M Jedrzejewski
- Centre for Process Systems Engineering, Department of Chemical Engineering, Imperial College London, London SW7 2AZ, UK.
| | - Ioscani Jimenez del Val
- Centre for Process Systems Engineering, Department of Chemical Engineering, Imperial College London, London SW7 2AZ, UK.
| | | | - Anne Dell
- Department of Life Sciences, Imperial College London, London SW7 2AZ, UK.
| | - Stuart M Haslam
- Department of Life Sciences, Imperial College London, London SW7 2AZ, UK.
| | - Karen M Polizzi
- Department of Life Sciences, Imperial College London, London SW7 2AZ, UK.
| | - Cleo Kontoravdi
- Centre for Process Systems Engineering, Department of Chemical Engineering, Imperial College London, London SW7 2AZ, UK.
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28
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Controllability analysis of protein glycosylation in CHO cells. PLoS One 2014; 9:e87973. [PMID: 24498415 PMCID: PMC3912168 DOI: 10.1371/journal.pone.0087973] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Accepted: 01/02/2014] [Indexed: 12/17/2022] Open
Abstract
To function as intended in vivo, a majority of biopharmaceuticals require specific glycan distributions. However, achieving a precise glycan distribution during manufacturing can be challenging because glycosylation is a non-template driven cellular process, with the potential for significant uncontrolled variability in glycan distributions. As important as the glycan distribution is to the end-use performance of biopharmaceuticals, to date, no strategy exists for controlling glycosylation on-line. However, before expending the significant amount of effort and expense required to develop and implement on-line control strategies to address the problem of glycosylation heterogeneity, it is imperative to assess first the extent to which the very complex process of glycosylation is controllable, thereby establishing what is theoretically achievable prior to any experimental attempts. In this work, we present a novel methodology for assessing the output controllability of glycosylation, a prototypical example of an extremely high-dimensional and very non-linear system. We first discuss a method for obtaining the process gain matrix for glycosylation that involves performing model simulations and data analysis systematically and judiciously according to a statistical design of experiments (DOE) scheme and then employing Analysis of Variance (ANOVA) to determine the elements of process gain matrix from the resulting simulation data. We then discuss how to use the resulting high-dimensional gain matrix to assess controllability. The utility of this method is demonstrated with a practical example where we assess the controllability of various classes of glycans and of specific glycoforms that are typically found in recombinant biologics produced with Chinese Hamster Ovary (CHO) cells. In addition to providing useful insight into the extent to which on-line glycosylation control is achievable in actual manufacturing processes, the results also have important implications for genetically engineering cell lines design for enhanced glycosylation controllability.
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29
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Behjousiar A, Constantinou A, Polizzi KM, Kontoravdi C. FIBS-enabled noninvasive metabolic profiling. J Vis Exp 2014:e51200. [PMID: 24513729 DOI: 10.3791/51200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
In the era of computational biology, new high throughput experimental systems are necessary in order to populate and refine models so that they can be validated for predictive purposes. Ideally such systems would be low volume, which precludes sampling and destructive analyses when time course data are to be obtained. What is needed is an in situ monitoring tool which can report the necessary information in real-time and noninvasively. An interesting option is the use of fluorescent, protein-based in vivo biological sensors as reporters of intracellular concentrations. One particular class of in vivo biosensors that has found applications in metabolite quantification is based on Förster Resonance Energy Transfer (FRET) between two fluorescent proteins connected by a ligand binding domain. FRET integrated biological sensors (FIBS) are constitutively produced within the cell line, they have fast response times and their spectral characteristics change based on the concentration of metabolite within the cell. In this paper, the method for constructing Chinese hamster ovary (CHO) cell lines that constitutively express a FIBS for glucose and glutamine and calibrating the FIBS in vivo in batch cell culture in order to enable future quantification of intracellular metabolite concentration is described. Data from fed-batch CHO cell cultures demonstrates that the FIBS was able in each case to detect the resulting change in the intracellular concentration. Using the fluorescent signal from the FIBS and the previously constructed calibration curve, the intracellular concentration was accurately determined as confirmed by an independent enzymatic assay.
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Affiliation(s)
- Alireza Behjousiar
- Centre for Process Systems Engineering, Department of Chemical Engineering and Chemical Technology, Imperial College London
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30
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Role of Chinese hamster ovary central carbon metabolism in controlling the quality of secreted biotherapeutic proteins. ACTA ACUST UNITED AC 2014. [DOI: 10.4155/pbp.13.65] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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31
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Lee SM, Kim YG, Lee EG, Lee GM. Digital mRNA profiling of N-glycosylation gene expression in recombinant Chinese hamster ovary cells treated with sodium butyrate. J Biotechnol 2014; 171:56-60. [DOI: 10.1016/j.jbiotec.2013.12.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2013] [Revised: 12/03/2013] [Accepted: 12/04/2013] [Indexed: 12/18/2022]
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32
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Analysis of Chinese hamster ovary cell metabolism through a combined computational and experimental approach. Cytotechnology 2013; 66:945-66. [PMID: 24292563 DOI: 10.1007/s10616-013-9648-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2013] [Accepted: 09/20/2013] [Indexed: 01/22/2023] Open
Abstract
Optimization of cell culture processes can benefit from the systematic analysis of experimental data and their organization in mathematical models, which can be used to decipher the effect of individual process variables on multiple outputs of interest. Towards this goal, a kinetic model of cytosolic glucose metabolism coupled with a population-level model of Chinese hamster ovary cells was used to analyse metabolic behavior under batch and fed-batch cell culture conditions. The model was parameterized using experimental data for cell growth dynamics, extracellular and intracellular metabolite profiles. The results highlight significant differences between the two culture conditions in terms of metabolic efficiency and motivate the exploration of lactate as a secondary carbon source. Finally, the application of global sensitivity analysis to the model parameters highlights the need for additional experimental information on cell cycle distribution to complement metabolomic analyses with a view to parameterize kinetic models.
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Kyriakopoulos S, Polizzi KM, Kontoravdi C. Comparative analysis of amino acid metabolism and transport in CHO variants with different levels of productivity. J Biotechnol 2013; 168:543-51. [PMID: 24056080 DOI: 10.1016/j.jbiotec.2013.09.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Revised: 09/10/2013] [Accepted: 09/12/2013] [Indexed: 12/12/2022]
Abstract
Chinese hamster ovary (CHO) cells are widely used for the production of biopharmaceuticals; however, our understanding of several physiological elements that contribute to productivity is limited. One of these is amino acid transport and how its limitation and/or regulation might affect productivity. To further our understanding, we have examined the expression of 40 mammalian amino acid transporter genes during batch cultures of three CHO cell lines: a non-producer and two antibody-producing cell lines with different levels of productivity. In parallel, extracellular and intracellular levels of amino acids were quantified. The aim was to identify differences in gene regulation between cell lines and within culture. Our results show that three transporters associated with transport of taurine and β-alanine, acidic amino acids and branched chain amino acids, are highly upregulated in both antibody-producing cell lines but not in the non-producer. Additionally, genes associated with the transport of amino acids related to the glutathione pathway (alanine, cysteine, cystine, glycine, glutamate) were found to be highly upregulated during the stationary phase of cell culture, correlating well with literature data on the importance of the pathway. Our analysis highlights potential markers for cell line selection and targets for process optimization.
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Affiliation(s)
- Sarantos Kyriakopoulos
- Centre for Process Systems Engineering, Department of Chemical Engineering, Imperial College London, London SW7 2AZ, UK
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Butler M, Meneses-Acosta A. Recent advances in technology supporting biopharmaceutical production from mammalian cells. Appl Microbiol Biotechnol 2012; 96:885-94. [PMID: 23053101 PMCID: PMC7080107 DOI: 10.1007/s00253-012-4451-z] [Citation(s) in RCA: 122] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Revised: 09/17/2012] [Accepted: 09/18/2012] [Indexed: 11/28/2022]
Abstract
The demand for production of glycoproteins from mammalian cell culture continues with an increased number of approvals as biopharmaceuticals for the treatment of unmet medical needs. This is particularly the case for humanized monoclonal antibodies which are the largest and fastest growing class of therapeutic pharmaceuticals. This demand has fostered efforts to improve the efficiency of production as well as to address the quality of the final product. Chinese hamster ovary cells are the predominant hosts for stable transfection and high efficiency production on a large scale. Specific productivity of recombinant glycoproteins from these cells can be expected to be above 50 pg/cell/day giving rise to culture systems with titers of around 5 g/L if appropriate fed-batch systems are employed. Cell engineering can delay the onset of programmed cell death to ensure prolonged maintenance of productive viable cells. The clinical efficacy and quality of the final product can be improved by strategic metabolic engineering. The best example of this is the targeted production of afucosylated antibodies with enhanced antibody-dependent cell cytotoxicity, an important function for use in cancer therapies. The development of culture media from non-animal sources continues and is important to ensure products of consistent quality and without the potential danger of contamination. Process efficiencies may also be improved by employing disposable bioreactors with the associated minimization of downtime. Finally, advances in downstream processing are needed to handle the increased supply of product from the bioreactor but maintaining the high purity demanded of these biopharmaceuticals.
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Affiliation(s)
- M Butler
- Department of Microbiology, University of Manitoba, Winnipeg, Manitoba, R3T 2N2, Canada.
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Wuest DM, Harcum SW, Lee KH. Genomics in mammalian cell culture bioprocessing. Biotechnol Adv 2012; 30:629-38. [PMID: 22079893 PMCID: PMC3718848 DOI: 10.1016/j.biotechadv.2011.10.010] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2011] [Revised: 09/20/2011] [Accepted: 10/30/2011] [Indexed: 12/14/2022]
Abstract
Explicitly identifying the genome of a host organism including sequencing, mapping, and annotating its genetic code has become a priority in the field of biotechnology with aims at improving the efficiency and understanding of cell culture bioprocessing. Recombinant protein therapeutics, primarily produced in mammalian cells, constitute a $108 billion global market. The most common mammalian cell line used in biologic production processes is the Chinese hamster ovary (CHO) cell line, and although great improvements have been made in titer production over the past 25 years, the underlying molecular and physiological factors are not well understood. Confident understanding of CHO bioprocessing elements (e.g. cell line selection, protein production, and reproducibility of process performance and product specifications) would significantly improve with a well understood genome. This review describes mammalian cell culture use in bioprocessing, the importance of obtaining CHO cell line genetic sequences, and the current status of sequencing efforts. Furthermore, transcriptomic techniques and gene expression tools are presented, and case studies exploring genomic techniques and applications aimed to improve mammalian bioprocess performance are reviewed. Finally, future implications of genomic advances are surmised.
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Affiliation(s)
- Diane M. Wuest
- Chemical Engineering and Delaware Biotechnology Institute, University of Delaware, 15 Innovation Way, Newark, DE 19711, USA
| | - Sarah W. Harcum
- Bioengineering, Clemson University, 301 Rhodes Research Center, Clemson, SC 29634, USA
| | - Kelvin H. Lee
- Chemical Engineering and Delaware Biotechnology Institute, University of Delaware, 15 Innovation Way, Newark, DE 19711, USA
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Markely LRA, Wang DIC. High-throughput analysis of intraclonal variability of glycoprotein sialylation. Biotechnol Prog 2011; 28:591-4. [DOI: 10.1002/btpr.738] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2011] [Revised: 09/24/2011] [Indexed: 01/01/2023]
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Brodsky AN, Caldwell M, Harcum SW. Glycosylation and post-translational modification gene expression analysis by DNA microarrays for cultured mammalian cells. Methods 2011; 56:408-17. [PMID: 22033470 DOI: 10.1016/j.ymeth.2011.10.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2011] [Revised: 10/07/2011] [Accepted: 10/11/2011] [Indexed: 01/14/2023] Open
Abstract
DNA microarray analysis of gene expression has become a valuable tool for bioprocessing research aimed at improving therapeutic protein yields. The highly parallel nature of DNA microarray technology allows researchers to assess hundreds of gene simultaneously, essentially enabling genome-wide snapshots. The quality and amount of therapeutic proteins produced by cultured mammalian cells rely heavily on the culture environment. In order to implement beneficial changes to the culture environment, a better understanding of the relationship between the product quality and culture environment must be developed. By analyzing gene expression levels under various environmental conditions, light can be shed on the underlying mechanisms. This paper describes a method for evaluating gene expression changes for cultured NS0 cells, a mouse-derived myeloma cell line, under culture environment conditions, such as ammonia buildup, known to affect product quality. These procedures can be easily adapted to other environmental conditions and any mammalian cell lines cultured in suspension, so long as a sufficient number of gene sequences are publicly available.
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Affiliation(s)
- Arthur Nathan Brodsky
- Department of Bioengineering, 301 Rhodes Research Center, Clemson University, Clemson, SC 29634-0905, USA
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Gramer MJ, Eckblad JJ, Donahue R, Brown J, Shultz C, Vickerman K, Priem P, van den Bremer ETJ, Gerritsen J, van Berkel PHC. Modulation of antibody galactosylation through feeding of uridine, manganese chloride, and galactose. Biotechnol Bioeng 2011; 108:1591-602. [PMID: 21328321 DOI: 10.1002/bit.23075] [Citation(s) in RCA: 130] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2010] [Revised: 12/15/2010] [Accepted: 01/18/2011] [Indexed: 12/20/2022]
Abstract
Through process transfer and optimization for increased antibody production to 3 g/L for a GS-CHO cell line, an undesirable drop in antibody Fc galactosylation was observed. Uridine (U), manganese chloride (M), and galactose (G), constituents involved in the intracellular galactosylation process, were evaluated in 2-L bioreactors for their potential to specifically increase antibody galactosylation. These components were placed in the feed medium at proportionally increasing concentrations from 0 to 20 × UMG, where a 1× concentration of U was 1 mM, a 1× concentration of M was 0.002 mM, and a 1× concentration of G was 5 mM. Antibody galactosylation increased rapidly from 3% at 0× UMG up to 21% at 8× UMG and then more slowly to 23% at 20× UMG. The increase was primarily due to a shift from G0F to G1F, with minimal impact on other glycoforms or product quality attributes. Cell culture performance was largely not impacted by addition of up to 20× UMG except for suppression of glucose consumption and lactate production at 16 and 20× UMG and a slight drop in antibody concentration at 20× UMG. Higher accumulation of free galactose in the medium was observed at 8× UMG and above, coincident with achieving the plateau of maximal galactosylation. A concentration of 4× UMG resulted in achieving the target of 18% galactosylation at 2-L scale, a result that was reproduced in a 1,000-L run. Follow-up studies to evaluate the addition of each component individually up to 12× concentration revealed that the effect was synergistic; the combination of all three components gave a higher level of galactosylation than addition of the each effect independently. The approach was found generally useful since a second cell line responded similarly, with an increase in galactosylation from 5% to 29% from 0 to 8× UMG and no further increase or impact on culture performance up to 12× UMG. These results demonstrate a useful approach to provide exact and specific control of antibody galactosylation through manipulation of the concentrations of uridine, manganese chloride, and galactose in the cell culture medium.
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Affiliation(s)
- Michael J Gramer
- Genmab MN, Inc., 9450 Winnetka Ave N, Brooklyn Park, Minnesota 55445, USA.
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Hossler P. Protein glycosylation control in mammalian cell culture: past precedents and contemporary prospects. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2011; 127:187-219. [PMID: 22015728 DOI: 10.1007/10_2011_113] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Protein glycosylation is a post-translational modification of paramount importance for the function, immunogenicity, and efficacy of recombinant glycoprotein therapeutics. Within the repertoire of post-translational modifications, glycosylation stands out as having the most significant proven role towards affecting pharmacokinetics and protein physiochemical characteristics. In mammalian cell culture, the understanding and controllability of the glycosylation metabolic pathway has achieved numerous successes. However, there is still much that we do not know about the regulation of the pathway. One of the frequent conclusions regarding protein glycosylation control is that it needs to be studied on a case-by-case basis since there are often conflicting results with respect to a control variable and the resulting glycosylation. In attempts to obtain a more multivariate interpretation of these potentially controlling variables, gene expression analysis and systems biology have been used to study protein glycosylation in mammalian cell culture. Gene expression analysis has provided information on how glycosylation pathway genes both respond to culture environmental cues, and potentially facilitate changes in the final glycoform profile. Systems biology has allowed researchers to model the pathway as well-defined, inter-connected systems, allowing for the in silico testing of pathway parameters that would be difficult to test experimentally. Both approaches have facilitated a macroscopic and microscopic perspective on protein glycosylation control. These tools have and will continue to enhance our understanding and capability of producing optimal glycoform profiles on a consistent basis.
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Affiliation(s)
- Patrick Hossler
- Abbott Laboratories, Abbott Bioresearch Center, Worcester, MA, 01605, USA,
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