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Song Y, Qian Y, Huang Z, Khattak SF, Li ZJ. Computational insights into O-glycosylation in a CTLA4 Fc-fusion protein linker and its impact on protein quality attributes. Comput Struct Biotechnol J 2020; 18:3925-3935. [PMID: 33335689 PMCID: PMC7734232 DOI: 10.1016/j.csbj.2020.11.037] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 11/21/2020] [Accepted: 11/23/2020] [Indexed: 12/21/2022] Open
Abstract
The hinge region of immunoglobulin G1 (IgG1) is used as a common linker for Fc-fusion therapeutic proteins. With the advances of high-resolution mass spectrometry and sample treatment strategies, unexpected O-linked glycosylation has been observed in the linker. However, the molecular mechanism involved in this unusual posttranslational modification is unknown. In this study, we applied site-direct mutagenesis, mass spectrometry, analytical chromatography, and computational modeling to investigate O-glycosylation processes in a clinically used CTLA4 Fc-fusion protein and its impacts on protein quality attributes. Surprisingly, O-glycans could be formed at new sites when an initial O-glycosylation site was eliminated, and continued to occur until all potential O-glycosylation sites were nulled. Site-preference of O-glycosylation initiation was attributed to the complex formation between the linker peptide and glycan transferase whereas the O-glycosylating efficiency and the linker flexibility were correlated using molecular modeling and simulations. As predicted, O-glycan-free CTLA4 Fc-fusion proteins were more homogenous for sialylation, and interestingly less prone to protein aggregation. Attenuating protein aggregation was a desirable effect, and could be related to the reduced presence of linker O-glycans that hindered inter-chain disulfide bond reformation. Findings from this study shed light on new therapeutic protein design and development.
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Affiliation(s)
- Yuanli Song
- Biologics Development, Bristol Myers Squibb Company, 38 Jackson Road, Devens, MA 01434, USA
| | - Yueming Qian
- Biologics Development, Bristol Myers Squibb Company, 38 Jackson Road, Devens, MA 01434, USA
| | - Zhe Huang
- Biologics Development, Bristol Myers Squibb Company, 38 Jackson Road, Devens, MA 01434, USA
| | - Sarwat F Khattak
- Biologics Development, Bristol Myers Squibb Company, 38 Jackson Road, Devens, MA 01434, USA
| | - Zheng Jian Li
- Biologics Development, Bristol Myers Squibb Company, 38 Jackson Road, Devens, MA 01434, USA
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Sowa SW, Qian Y, Aron KL, Xu P, Langsdorf E, Warrack B, Aranibar N, Tremml G, Xu J, McVey D, Reily M, Khetan A, Borys MC, Li ZJ. Metabolomic and quality data for early and late passages of an antibody-producing industrial CHO cell line. Data Brief 2020; 33:106591. [PMID: 33318978 PMCID: PMC7724160 DOI: 10.1016/j.dib.2020.106591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 10/30/2020] [Accepted: 11/23/2020] [Indexed: 11/25/2022] Open
Abstract
In this article, we provide four data sets for an industrial Chinese Hamster Ovary (CHO) cell line producing antibodies during a 14-day bioreactor run. This cell line was selected for further evaluation because of its significant titer loss as the cells were passaged over time. Four conditions that differed in cell bank ages were run for this dataset. Specifically, cells were passaged to passage 12, 21, 25, and 37 and then used in this experiment. Once the run commenced the following datasets were gathered: 1). Glycosylation data for each reactor 2). Size Exclusion Chromatography (SEC) data for the antibodies produced which allowed for the identification of high and low molecular weight species in the samples (N-Glycan and SEC data was taken on day 14 only). 3/4). Metabolites levels measured using Nuclear Magnetic Resonance (NMR) and liquid chromatography-mass spectroscopy (LC-MS) for all reactors over the time course of days 1, 4, 6, 8, 12, and 14. We also provide a graph of the glutamine levels for cells of different ages as an example of the utility of the data. These metabolomics data provide relative amounts for 36 metabolites (NMR) and 109 metabolites (LC-MS) over the 14-day time course. These data were collected in connection with a co-submitted paper [1].
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Affiliation(s)
- Steven W. Sowa
- Biologics Development, Global Product Development and Supply, Bristol-Myers Squibb Company, Devens, MA 01434, USA
| | - Yueming Qian
- Biologics Development, Global Product Development and Supply, Bristol-Myers Squibb Company, Devens, MA 01434, USA
| | - Kathryn L. Aron
- Biologics Development, Global Product Development and Supply, Bristol-Myers Squibb Company, Devens, MA 01434, USA
| | - Ping Xu
- Biologics Development, Global Product Development and Supply, Bristol-Myers Squibb Company, New Brunswick, NJ 08901, USA
| | - Erik Langsdorf
- Biologics Development, Global Product Development and Supply, Bristol-Myers Squibb Company, New Brunswick, NJ 08901, USA
| | - Bethanne Warrack
- Drug Development and Preclinical Studies, Bristol-Myers Squibb Company, Princeton, NJ, 08540, USA
| | - Nelly Aranibar
- Drug Development and Preclinical Studies, Bristol-Myers Squibb Company, Princeton, NJ, 08540, USA
| | - Gabi Tremml
- Biologics Development, Global Product Development and Supply, Bristol-Myers Squibb Company, New Brunswick, NJ 08901, USA
| | - Jianlin Xu
- Biologics Development, Global Product Development and Supply, Bristol-Myers Squibb Company, Devens, MA 01434, USA
| | - Duncan McVey
- Biologics Development, Global Product Development and Supply, Bristol-Myers Squibb Company, New Brunswick, NJ 08901, USA
| | - Michael Reily
- Drug Development and Preclinical Studies, Bristol-Myers Squibb Company, Princeton, NJ, 08540, USA
| | - Anurag Khetan
- Biologics Development, Global Product Development and Supply, Bristol-Myers Squibb Company, New Brunswick, NJ 08901, USA
| | - Michael C. Borys
- Biologics Development, Global Product Development and Supply, Bristol-Myers Squibb Company, Devens, MA 01434, USA
| | - Zheng Jian Li
- Biologics Development, Global Product Development and Supply, Bristol-Myers Squibb Company, Devens, MA 01434, USA
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Perfusion reduces bispecific antibody aggregation via mitigating mitochondrial dysfunction-induced glutathione oxidation and ER stress in CHO cells. Sci Rep 2020; 10:16620. [PMID: 33024175 PMCID: PMC7538420 DOI: 10.1038/s41598-020-73573-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 09/15/2020] [Indexed: 01/07/2023] Open
Abstract
One major challenge observed for the expression of therapeutic bispecific antibodies (BisAbs) is high product aggregates. Aggregates increase the risk of immune responses in patients and therefore must be removed at the expense of purification yields. BisAbs contain engineered disulfide bonds, which have been demonstrated to form product aggregates, if mispaired. However, the underlying intracellular mechanisms leading to product aggregate formation remain unknown. We demonstrate that impaired glutathione regulation underlies BisAb aggregation formation in a CHO cell process. Aggregate formation was evaluated for the same clonal CHO cell line producing a BisAb using fed-batch and perfusion processes. The perfusion process produced significantly lower BisAb aggregates compared to the fed-batch process. Perfusion bioreactors attenuated mitochondrial dysfunction and ER stress resulting in a favorable intracellular redox environment as indicated by improved reduced to oxidized glutathione ratio. Conversely, mitochondrial dysfunction-induced glutathione oxidation and ER stress disrupted the intracellular redox homeostasis, leading to product aggregation in the fed-batch process. Combined, our results demonstrate that mitochondrial dysfunction and ER stress impaired glutathione regulation leading to higher product aggregates in the fed-batch process. This is the first study to utilize perfusion bioreactors as a tool to demonstrate the intracellular mechanisms underlying product aggregation formation.
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Hamann A, Kozisek T, Broad K, Pannier AK. Glucocorticoid Priming of Nonviral Gene Delivery to hMSCs Increases Transfection by Reducing Induced Stresses. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2020; 18:713-722. [PMID: 32913879 PMCID: PMC7452153 DOI: 10.1016/j.omtm.2020.07.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Accepted: 07/17/2020] [Indexed: 12/12/2022]
Abstract
Human mesenchymal stem cells (hMSCs) are under study for cell and gene therapeutics because of their immunomodulatory and regenerative properties. Safe and efficient gene delivery could increase hMSC clinical potential by enabling expression of transgenes for control over factor production, behavior, and differentiation. Viral delivery is efficient but suffers from safety issues, while nonviral methods are safe but highly inefficient, especially in hMSCs. We previously demonstrated that priming cells with glucocorticoids (Gcs) before delivery of DNA complexes significantly increases hMSC transfection, which correlates with a rescue of transfection-induced metabolic and protein synthesis decline, and apoptosis. In this work, we show that transgene expression enhancement is mediated by transcriptional activation of endogenous hMSC genes by the cytosolic glucocorticoid receptor (cGR) and that transfection enhancement can be potentiated with a GR transcription-activation synergist. We demonstrate that the Gc-activated cGR modulates endogenous hMSC gene expression to ameliorate transfection-induced endoplasmic reticulum (ER) and oxidative stresses, apoptosis, and inflammatory responses to prevent hMSC metabolic and protein synthesis decline, resulting in enhanced transgene expression after nonviral gene delivery to hMSCs. These results provide insights important for rational design of more efficient nonviral gene delivery and priming techniques that could be utilized for clinical hMSC applications.
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Affiliation(s)
- Andrew Hamann
- Department of Biological Systems Engineering, University of Nebraska-Lincoln, Lincoln, NE 68583-0726, USA
| | - Tyler Kozisek
- Department of Biological Systems Engineering, University of Nebraska-Lincoln, Lincoln, NE 68583-0726, USA
| | - Kelly Broad
- Department of Biological Systems Engineering, University of Nebraska-Lincoln, Lincoln, NE 68583-0726, USA
| | - Angela K Pannier
- Department of Biological Systems Engineering, University of Nebraska-Lincoln, Lincoln, NE 68583-0726, USA
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Kozisek T, Hamann A, Nguyen A, Miller M, Plautz S, Pannier AK. High-throughput screening of clinically approved drugs that prime nonviral gene delivery to human Mesenchymal stem cells. J Biol Eng 2020; 14:16. [PMID: 32467728 PMCID: PMC7238544 DOI: 10.1186/s13036-020-00238-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 05/04/2020] [Indexed: 01/07/2023] Open
Abstract
Background Human mesenchymal stem cells (hMSCs) are intensely researched for applications in cell therapeutics due to their unique properties, however, intrinsic therapeutic properties of hMSCs could be enhanced by genetic modification. Viral transduction is efficient, but suffers from safety issues. Conversely, nonviral gene delivery, while safer compared to viral, suffers from inefficiency and cytotoxicity, especially in hMSCs. To address the shortcomings of nonviral gene delivery to hMSCs, our lab has previously demonstrated that pharmacological 'priming' of hMSCs with the glucocorticoid dexamethasone can significantly increase transfection in hMSCs by modulating transfection-induced cytotoxicity. This work seeks to establish a library of transfection priming compounds for hMSCs by screening 707 FDA-approved drugs, belonging to diverse drug classes, from the NIH Clinical Collection at four concentrations for their ability to modulate nonviral gene delivery to adipose-derived hMSCs from two human donors. Results Microscope images of cells transfected with a fluorescent transgene were analyzed in order to identify compounds that significantly affected hMSC transfection without significant toxicity. Compound classes that increased transfection across both donors included glucocorticoids, antibiotics, and antihypertensives. Notably, clobetasol propionate, a glucocorticoid, increased transgene production 18-fold over unprimed transfection. Furthermore, compound classes that decreased transfection across both donors included flavonoids, antibiotics, and antihypertensives, with the flavonoid epigallocatechin gallate decreasing transgene production - 41-fold compared to unprimed transfection. Conclusions Our screen of the NCC is the first high-throughput and drug-repurposing approach to identify nonviral gene delivery priming compounds in two donors of hMSCs. Priming compounds and classes identified in this screen suggest that modulation of proliferation, mitochondrial function, and apoptosis is vital for enhancing nonviral gene delivery to hMSCs.
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Affiliation(s)
- Tyler Kozisek
- 1Department of Biological Systems Engineering, University of Nebraska-Lincoln, 231 L.W. Chase Hall, Lincoln, NE USA
| | - Andrew Hamann
- 1Department of Biological Systems Engineering, University of Nebraska-Lincoln, 231 L.W. Chase Hall, Lincoln, NE USA
| | - Albert Nguyen
- 1Department of Biological Systems Engineering, University of Nebraska-Lincoln, 231 L.W. Chase Hall, Lincoln, NE USA
| | - Michael Miller
- 2Department of Biomedical Engineering, Pennsylvania State University, 122 Chemical and Biomedical Engineering Building, University Park, PA USA
| | - Sarah Plautz
- 1Department of Biological Systems Engineering, University of Nebraska-Lincoln, 231 L.W. Chase Hall, Lincoln, NE USA
| | - Angela K Pannier
- 1Department of Biological Systems Engineering, University of Nebraska-Lincoln, 231 L.W. Chase Hall, Lincoln, NE USA
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Hamann A, Broad K, Nguyen A, Pannier AK. Mechanisms of unprimed and dexamethasone-primed nonviral gene delivery to human mesenchymal stem cells. Biotechnol Bioeng 2018; 116:427-443. [PMID: 30450542 PMCID: PMC6322959 DOI: 10.1002/bit.26870] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Revised: 10/10/2018] [Accepted: 11/16/2018] [Indexed: 12/16/2022]
Abstract
Human mesenchymal stem cells (hMSCs) are under intense study for applications of cell and gene therapeutics because of their unique immunomodulatory and regenerative properties. Safe and efficient genetic modification of hMSCs could increase their clinical potential by allowing functional expression of therapeutic transgenes or control over behavior and differentiation. Viral gene delivery is efficient, but suffers from safety issues, while nonviral methods are safe, but highly inefficient, especially in hMSCs. Our lab previously demonstrated that priming cells before delivery of DNA complexes with dexamethasone (DEX), an anti‐inflammatory glucocorticoid drug, significantly increases hMSC transfection success. This work systematically investigates the mechanisms of hMSC transfection and DEX‐mediated enhancement of transfection. Our results show that hMSC transfection and its enhancement by DEX are decreased by inhibiting classical intracellular transport and nuclear import pathways, but DEX transfection priming does not increase cellular or nuclear internalization of plasmid DNA (pDNA). We also show that hMSC transgene expression is largely affected by pDNA promoter and enhancer sequence changes, but DEX‐mediated enhancement of transfection is unaffected by any pDNA sequence changes. Furthermore, DEX‐mediated transfection enhancement is not the result of increased transgene messenger RNA transcription or stability. However, DEX‐priming increases total protein synthesis by preventing hMSC apoptosis induced by transfection, resulting in increased translation of transgenic protein. DEX may also promote further enhancement of transgenic reporter enzyme activity by other downstream mechanisms. Mechanistic studies of nonviral gene delivery will inform future rationally designed technologies for safe and efficient genetic modification of clinically relevant cell types.
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Affiliation(s)
- Andrew Hamann
- Department of Biological Systems Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska
| | - Kelly Broad
- Department of Biological Systems Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska
| | - Albert Nguyen
- Department of Biological Systems Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska
| | - Angela K Pannier
- Department of Biological Systems Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska
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Andrade C, Arnold L, Motabar D, Aspelund M, Tang A, Hunter A, Chung WK. An Integrated Approach to Aggregate Control for Therapeutic Bispecific Antibodies Using an Improved Three Column Mab Platform-Like Purification Process. Biotechnol Prog 2018; 35:e2720. [PMID: 30298991 PMCID: PMC6667909 DOI: 10.1002/btpr.2720] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 09/17/2018] [Accepted: 09/17/2018] [Indexed: 12/23/2022]
Abstract
Single chain variable fragment‐IgGs (scFv‐IgG) are a class of bispecific antibodies consisting of two single chain variable fragments (scFv) that are fused to an intact IgG molecule. A common trend observed for expression of scFv‐IgGs in mammalian cell culture is a higher level of aggregates (10%–30%) compared to mAbs, which results in lower purification yields in order to meet product quality targets. Furthermore, the high aggregate levels also pose robustness risks to a conventional mAb three column platform purification process which uses only the polishing steps (e.g., cation exchange chromatography [CEX]) for aggregate removal. Protein A chromatography with pH gradient elution, high performance tangential flow filtration (HP‐TFF) and calcium phosphate precipitation were evaluated at the bench scale as means of introducing orthogonal aggregate removal capabilities into other aspects of the purification process. The two most promising process variants, namely Protein A pH gradient elution followed by calcium phosphate precipitation were evaluated at pilot scale, demonstrating comparable performance. Implementing Protein A chromatography with gradient elution and/or calcium phosphate precipitation removed a sufficient portion of the aggregate burden prior to the CEX polishing step, enabling CEX to be operated robustly under conditions favoring higher monomer yield. From starting aggregate levels ranging from 15% to 23% in the condition media, levels were reduced to between 2% and 3% at the end of the CEX step. The overall yield for the optimal process was 71%. Results of this work suggest an improved three‐column mAb platform‐like purification process for purification of high aggregate scFv‐IgG bispecific antibodies is feasible. © 2018 The Authors. Biotechnology Progress published by Wiley Periodicals, Inc. on behalf of American Institute of Chemical Engineers. Biotechnol. Prog., 35: e2720, 2019
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Affiliation(s)
- Cassia Andrade
- Purification Process Sciences, MedImmune LLC, One MedImmune Way, Gaithersburg, Maryland, 20878
| | - Lindsay Arnold
- Process Development Engineering, MedImmune LLC, One MedImmune Way, Gaithersburg, Maryland, 20878
| | - Dana Motabar
- Purification Process Sciences, MedImmune LLC, One MedImmune Way, Gaithersburg, Maryland, 20878
| | - Matthew Aspelund
- Purification Process Sciences, MedImmune LLC, One MedImmune Way, Gaithersburg, Maryland, 20878
| | - Alison Tang
- Purification Process Sciences, MedImmune LLC, Cambridge, U.K
| | - Alan Hunter
- Purification Process Sciences, MedImmune LLC, One MedImmune Way, Gaithersburg, Maryland, 20878
| | - Wai Keen Chung
- Purification Process Sciences, MedImmune LLC, One MedImmune Way, Gaithersburg, Maryland, 20878
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Chumsae C, Hossler P, Raharimampionona H, Zhou Y, McDermott S, Racicot C, Radziejewski C, Zhou ZS. When Good Intentions Go Awry: Modification of a Recombinant Monoclonal Antibody in Chemically Defined Cell Culture by Xylosone, an Oxidative Product of Ascorbic Acid. Anal Chem 2015; 87:7529-34. [DOI: 10.1021/acs.analchem.5b00801] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Chris Chumsae
- Protein
Analytics, Process Sciences Department, AbbVie Bioresearch Center, Worcester, Massachusetts 01605, United States
- Barnett
Institute of Chemical and Biological Analysis, Department of Chemistry
and Chemical Biology, Northeastern University, Boston, Massachusetts 02115, United States
| | - Patrick Hossler
- Cell
Culture, Process Sciences Department, AbbVie Bioresearch Center, Worcester, Massachusetts 01605, United States
| | - Haly Raharimampionona
- Protein
Analytics, Process Sciences Department, AbbVie Bioresearch Center, Worcester, Massachusetts 01605, United States
| | - Yu Zhou
- Protein
Analytics, Process Sciences Department, AbbVie Bioresearch Center, Worcester, Massachusetts 01605, United States
| | - Sean McDermott
- Cell
Culture, Process Sciences Department, AbbVie Bioresearch Center, Worcester, Massachusetts 01605, United States
| | - Chris Racicot
- Cell
Culture, Process Sciences Department, AbbVie Bioresearch Center, Worcester, Massachusetts 01605, United States
| | - Czeslaw Radziejewski
- Protein
Analytics, Process Sciences Department, AbbVie Bioresearch Center, Worcester, Massachusetts 01605, United States
| | - Zhaohui Sunny Zhou
- Barnett
Institute of Chemical and Biological Analysis, Department of Chemistry
and Chemical Biology, Northeastern University, Boston, Massachusetts 02115, United States
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Strand J, Huang CT, Xu J. Characterization of Fc-fusion protein aggregates derived from extracellular domain disulfide bond rearrangements. J Pharm Sci 2012; 102:441-53. [PMID: 23242781 DOI: 10.1002/jps.23421] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2012] [Revised: 11/05/2012] [Accepted: 11/28/2012] [Indexed: 01/14/2023]
Abstract
Aggregation of protein biotherapeutics has consequences for decreasing production and has been implicated in immunogenicity. The mechanisms of protein aggregation vary depending on the protein and the expression system utilized, making it difficult to elucidate the conditions that promote their formation. Nonnative aggregation of recombinant immunoglobulin G protein therapeutics from mammalian expression systems has been extensively studied. To better understand the mechanisms behind aggregation of glycosylated fusion proteins produced in Chinese hamster ovarian cells, we have examined the high-molecular-weight (HMW) species of activin receptor-like kinase 1 Fc fusion protein. Size-exclusion chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis indicate that two populations of aggregate exist: (1) nondisulfide-linked, higher-order aggregates and (2) disulfide-linked oligomers. The largest aggregated species have increased nonnative structure, whereas the smallest aggregated species maintain structure similar to monomer. The HMW species display decreased levels of O-linked glycosylation, higher occupancy of high-mannose N-linked oligosaccharide structures, and overall less sialylation as their size increases. Disulfide-linked aggregate species were found to associate through the extracellular domain. N-linked glycosylation on the extracellular domain (ECD) appears to discourage disulfide-linked aggregation. Elucidation of the specific mechanisms behind disulfide-linked aggregate formation may assist in designing processes that limit aggregate formation in cell culture, with implications for increased production.
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Affiliation(s)
- James Strand
- Acceleron Pharma, Cambridge, Massachusetts 02139, USA
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RETRACTED ARTICLE: Simultaneous expression of antibody light and heavy chains in Pichia pastoris: improving retransformation outcome by linearizing vector at a different site. Appl Microbiol Biotechnol 2012; 96:1381. [DOI: 10.1007/s00253-012-4347-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2012] [Revised: 07/26/2012] [Accepted: 07/30/2012] [Indexed: 10/28/2022]
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Jing Y, Qian Y, Ghandi M, He A, Borys MC, Pan SH, Li ZJ. A mechanistic study on the effect of dexamethasone in moderating cell death in Chinese Hamster Ovary cell cultures. Biotechnol Prog 2011; 28:490-6. [PMID: 22140034 DOI: 10.1002/btpr.747] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2011] [Revised: 09/30/2011] [Indexed: 11/08/2022]
Abstract
Dexamethasone (DEX) was previously shown (Jing et al., Biotechnol Bioeng. 2010;107:488-496) to play a dual role in increasing sialylation of recombinant glycoproteins produced by Chinese Hamster Ovary (CHO) cells. DEX addition increased sialic acid levels of a recombinant fusion protein through increased expression of α2,3-sialyltransferase and β1,4-galactosyltransferase, but also decreased the sialidase-mediated, extracellular degradation of sialic acid through slowing cell death at the end of the culture period. This study examines the underlying mechanism for this cytoprotective action by studying the transcriptional response of the CHO cell genome upon DEX treatment using DNA microarrays and gene ontology term analysis. Many of those genes showing a significant transcriptional response were associated with the regulation of programmed cell death. The gene with the highest change in expression level, as validated by Quantitative PCR assays with TaqMan® probes and confirmed by Western Blot analysis, was the antiapoptotic gene Tsc22d3, also referred to as GILZ (glucocorticoid-induced leucine zipper). The pathway by which DEX suppressed cell death towards the end of the culture period was also confirmed by showing involvement of glucocorticoid receptors and GILZ through studies using the glucocorticoid antagonist mifepristone (RU-486). These findings advance the understanding of the mechanism by which DEX suppresses cell death in CHO cells and provide a rationale for the application of glucocorticoids in CHO cell culture processes.
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Affiliation(s)
- Ying Jing
- Biologics Process and Product Development, Technical Operations, Bristol-Myers Squibb Company, East Syracuse, NY 13057, USA
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Qian Y, Khattak SF, Xing Z, He A, Kayne PS, Qian NX, Pan SH, Li ZJ. Cell culture and gene transcription effects of copper sulfate on Chinese hamster ovary cells. Biotechnol Prog 2011; 27:1190-4. [DOI: 10.1002/btpr.630] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2011] [Revised: 03/28/2011] [Indexed: 12/14/2022]
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