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Cited by 299Viral Infectious Diseases and Gene Expression in InsectsProtein purification and stabilityGlycosylation and Glycoproteins Research

Therapeutic glycoprotein production in mammalian cells

Open access
Lalonde, Marie-Eve, Durocher, Yves·2017·Journal of Biotechnology
DOI 10.1016/j.jbiotec.2017.04.028
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Abstract

Over the last years, the biopharmaceutical industry has significantly turned its biologics production towards mammalian cell expression systems. The presence of glycosylation machineries within these systems, and the fact that monoclonal antibodies represent today the vast majority of new therapeutic candidates, has largely influenced this new direction. Recombinant glycoproteins, including monoclonal antibodies, have shown different biological properties based on their glycan profiles. Thus, the industry has developed cell engineering strategies not only to improve cell's specific productivity, but also to adapt their glycosylation profiles for increased therapeutic activity. Additionally, the advance of "omics" technologies has recently given rise to new possibilities in improving these expression platforms and will significantly help developing new strategies, in particular for CHO (Chinese Hamster Ovary) cells.

AI snapshot

Written from the paper’s full text.

TL;DR

This review summarizes mammalian-cell production of therapeutic glycoproteins, with a focus on CHO cells, cell-engineering strategies, glycoengineering, and “omics” tools. It argues that CHO remains dominant, while human cell lines and targeted glycoengineering offer routes to more human-like glycosylation and improved therapeutic activity.

Key findings

  • CHO cells are involved in production of over 70% of recombinant biopharmaceutical proteins, most of them monoclonal antibodies; in 2015, more than half of the thirteen new biologics approved were recombinant proteins produced in CHO cells, with the same trend observed in 2016.
  • CHO cells cannot perform some human glycosylation, such as α-2,6-sialylation and α-1,3/4-fucosylation, and can produce Neu5Gc and α-gal at low levels (e.g., <2% and <0.2%, respectively); murine myeloma cells can produce these at considerably higher levels, increasing immunogenicity risk.
  • Human cell lines such as HEK293 and HT-1080 can provide more human-like glycosylation; examples include rFVIIIFc and rFIXFc produced in HEK293 with greater tyrosine sulfation and γ-carboxylation and no α-gal or Neu5Gc compared with CHO.
  • Glycoengineering strategies focus on reducing fucosylation to enhance ADCC and increasing sialylation to improve half-life; omics efforts include CHO genome sequencing, transcriptomic assembly of 29,000 transcripts and 13,187 mRNA transcripts, and proteomic identification of 6,164 proteins from CHO-K1 proteome/glycoproteome.

Methods

  • Narrative review of mammalian expression systems, cell engineering, glycoengineering, and “omics” approaches for therapeutic glycoprotein production.
  • No primary experimental design, sample, or statistical analysis is reported; the paper synthesizes published literature and examples from industry and academic studies.
  • Main analysis is qualitative synthesis of expression hosts, selection/gene-expression systems, cell growth and secretion engineering, glycosylation engineering, and genomics/transcriptomics/proteomics/metabolomics.

Limitations

  • The paper does not state explicit limitations.
  • Evident from the text: it is a narrative review without a systematic search strategy, inclusion criteria, or quantitative meta-analysis, so coverage and conclusions are selective.
  • The text itself notes conflicting or mixed results for several strategies, including anti-apoptosis engineering, chaperone overexpression, and MAR element activity, indicating that some conclusions remain uncertain.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1016/j.jbiotec.2017.04.028

Cites

259 of 259 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

68 of 241 cited sources checked · 32 supported · 0 flagged · accuracy not yet measured

  • Premisecitation

    Different gene amplification systems developed and used in CHO cells allow high titer yields and good specific productivity.

    “Moreover, different gene amplification systems have been developed and used in CHO cells, which allow for high titer yields and good specific productivity (Durocher and Butler, 2009;Kim et al., 2012;Lai et al., 2013).”
    Quote in the paperNot a substantial claim1 of 3 sources checked
    • cites Durocher and Butler, 2009 source
    • cites Kim et al., 2012 source
    • cites Lai et al., 2013 source
  • Interpretationcitation

    Because CHO cells produce recombinant glycoproteins with human-like glycans, the generated products are more likely to be compatible and bioactive within human hosts.

    “Since CHO cells produce recombinant glycoproteins with human-like glycans, the generated products are to more likely be compatible and bioactive within human hosts (Kim et al., 2012;Lai et al., 2013).”
    Quote in the paperSubstantial claim1 of 2 sources checked
    • cites Kim et al., 2012 source
    • cites Lai et al., 2013 source
  • Premisecitation

    CHO cells have limited ability to gamma-carboxylate recombinant proteins such as clotting factors.

    “CHO cells also have limited ability to gamma-carboxylate recombinant proteins such as clotting factors (Kumar 2015), even though some improvements have been achieved through metabolic engineering work (Rehemtulla et al., 1993;Liu et al., 2014).”
    Quote in the paperNot a substantial claim2 of 3 sources checked
    • cites Kumar 2015 source
    • cites Rehemtulla et al., 1993 source

      The paper reports that expressing gamma-carboxylase in CHO cells increased in vitro enzyme activity, but did not improve the specific procoagulant activity of secreted factor IX. Expressing the propeptide-processing enzyme PACE improved factor IX activity threefold. Thus, the cited work supports an improvement through cell engineering, but not an improvement in gamma-carboxylation of the secreted clotting factor. (LLM, conf=0.84)

      Experimental — accuracy not yet measured
    • cites Liu et al., 2014 source
  • Premisecitation

    CHO cells produce glycans that do not occur in human cells, namely Neu5Gc and α-gal, at very low levels (<2% and <0.2% respectively).

    “Moreover, CHO cells produce glycans that do not occur in human cells, namely N-glycolylneuraminic acid (Neu5Gc) and galactose-α1,3-galactose (α-gal), even though these occurring at very low levels (e.g < 2% and < 0.2% respectively) (Bosques et al., 2010;Ghaderi et al., 2010;Dietmair et al., 2012b;Ghaderi et al., 2012).”
    Quote in the paperNot a substantial claim2 of 3 sources checked
    • cites Bosques et al., 2010 source

      In “To the Editor” (page unavailable), the paper shows that CHO-produced proteins can contain α-Gal and reports an α-Gal–containing glycan in abatacept at approximately 0.2% of total N-linked glycans. That is a product-specific estimate, not a general level below 0.2%. Our copy does not address Neu5Gc or its claimed level below 2%, nor does it explicitly state that these glycans do not occur in human cells. (LLM, conf=0.87)

      Experimental — accuracy not yet measured
    • cites Ghaderi et al., 2010 source

      The paper states that humans cannot synthesize α-gal or Neu5Gc and that glycoproteins produced in CHO cells carry small amounts of Neu5Gc (body text, indexed under Abstract; page unavailable). It does not establish α-gal production specifically in CHO cells or give the claimed <2% and <0.2% levels. It also notes that human cells can incorporate Neu5Gc from animal-derived culture materials, so ‘do not occur in human cells’ is too absolute. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
    • cites Dietmair et al., 2012b

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Premisecitation

    Co-expression of furin allowed the production of fully cleaved and active von Willebrand factor in an industrial-scale CHO perfusion system.

    “For example, co-expression of furin was shown to allow the production of fully cleaved and active von Willebrand factor in an industrial-scale CHO perfusion system (Fischer et al., 1995)”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Fischer et al., 1995 source

      The Expression section describes furin-coexpressing CHO cells grown in industrial-scale perfusion bioreactors. The structural analysis (section labeled Preparation; page unavailable) reports that the resulting vWF was completely processed and composed of intact, mature subunits. It identifies multimers associated with hemostatic activity but does not demonstrate the produced vWF’s activity with a functional test. (LLM, conf=0.85)

      Experimental — accuracy not yet measured
  • May combine two claims. 47
  • Classified as probably not a substantial claim. 30
  • The quote only partly states this claim. 1

  • May combine two claims.

    Premisecitation

    CHO cells can achieve substantial production rate, are suitable for large-scale industrial suspension culture, and can be adapted to grow in various serum-free and chemically defined culture media.

    “These cells can achieve substantial production rate, are suitable for large-scale industrial suspension culture and can be adapted to grow in various serum-free and chemically defined culture media (Kim et al., 2012;Lai et al., 2013).”
    Quote in the paperSubstantial claim1 of 2 sources checked
    • cites Kim et al., 2012 source
    • cites Lai et al., 2013 source

  • May combine two claims.

    Premisecitation

    Proper glycosylation profiles can improve recombinant protein properties by increasing stability and half-life in blood circulation and decreasing immunogenicity.

    “Studies have demonstrated that proper glycosylation profiles can improve recombinant protein properties such as increase their stability and half-life in blood circulation and decrease their immunogenicity (Ashwell and Harford, 1982;Runkel et al., 1998;Ghaderi et al., 2010;Ghaderi et al., 2012;Jefferis, 2016a;Jefferis, 2016b;Kuriakose et al., 2016).”
    Quote in the paperSubstantial claim1 of 3 sources checked
    • cites Ashwell and Harford, 1982 source
    • cites Runkel et al., 1998 source
    • cites Ghaderi et al., 2010 source

  • May combine two claims.

    Premisecitation

    Plants produce core α1,3-fructose and β1,2-xylose, which are completely absent in human cells and could be immunogenic.

    “Indeed, plants produce core α1,3-fructose and β1,2-xylose, which are completely absent in human cells and could be immunogenic (Karg et al., 2009;Ghaderi et al., 2012).”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites Karg et al., 2009 source
    • cites Ghaderi et al., 2012 source

      The plant-based expression systems section says plant N-glycans may carry β1,2-xylose and α1,3-fucose residues that are absent in humans and may be immunogenic. The claim says “fructose” rather than the paper’s “fucose,” so that component is not supported as written. (LLM, conf=0.88)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Premisecitation

    CAP and HuH-7 cells display human-like glycosylation profiles.

    “Two other cell lines, the CAP (CEVEC's Amniocyte Production) cells of human amniocytes origin and the HuH-7 cells of human hepatocellular carcinoma origin, are presently tested for recombinant glycoprotein production in preclinical phases and both display human-like glycosylation profiles (Schiedner et al., 2008;Wolfel et al., 2011;Enjolras et al., 2012;Swiech et al., 2012;Wissing et al., 2015).”
    Quote in the paperNot a substantial claim2 of 3 sources checked
    • cites Schiedner et al., 2008 source

      The Results section (page unavailable) reports that hAAT produced in human amniocyte cell lines was glycosylated and sialylated, with test results comparable to hAAT from human serum. This supports a human-like feature for the amniocyte-derived cells, but the paper does not establish a full glycosylation profile for CAP cells or address HuH-7 cells. (LLM, conf=0.86)

      Experimental — accuracy not yet measured
    • cites Wolfel et al., 2011 source

      The Summary (page not provided) says proteins produced by CAP-T cells showed a fully human posttranslational modification pattern, also observed in the original CAP cells. The Background describes CAP cells as producing proteins with authentic human posttranslational modifications. These passages support the claim for CAP cells, but the paper does not address HuH-7 cells or their glycosylation profiles. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
    • cites Enjolras et al., 2012 source

  • May combine two claims.

    Premisecitation

    Velaglucerase alfa and other β-glucocerebrosidases produced in CHO and carrot cells show diverse glycan profiles but similar macrophage uptake, in vitro enzymatic activity, stability, and efficacy.

    “Even though these three products show diverse glycan profiles, they showed similar macrophage uptake, in vitro enzymatic activity, stability and efficacy (Ben Turkia et al., 2013;Tekoah et al., 2013).”
    Quote in the paperNot a substantial claim2 of 2 sources checked
    • cites Ben Turkia et al., 2013 source

      The Introduction (page not specified) describes different glycan compositions, while the trial results report non-inferior clinical efficacy for velaglucerase alfa versus imiglucerase. But the Introduction says velaglucerase alfa enters cultured human macrophages more rapidly, not at a similar rate. This paper does not establish comparable in vitro activity or stability, or compare a carrot-cell product. (LLM, conf=0.90)

      Experimental — accuracy not yet measured
    • cites Tekoah et al., 2013 source

      The Introduction table identifies the three enzymes as produced in human fibrosarcoma, CHO, and carrot cells. The Discussion reports different glycan profiles but comparable enzymatic activity, stability, and macrophage uptake. It says clinical trial data *suggest* no significant differences in clinical improvement, rather than establishing similar efficacy as a finding of this study. (LLM, conf=0.83)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Premisecitation

    Neutralizing anti-Imiglucerase antibodies were observed in 24% of patients, with an impact on the protein activity.

    “Notably, neutralizing anti-Imiglucerase antibodies were observed in 24% of patients, with an impact on the protein activity (Ben Turkia et al., 2013).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Ben Turkia et al., 2013 source

      The Discussion reports anti-imiglucerase antibodies in 23.5% of treated patients, approximately 24%. The Adverse events section identifies neutralizing antibodies that inhibited enzyme activity in vitro in one patient, but does not say that all four antibody-positive patients had neutralizing antibodies. The claim incorrectly applies the 24% figure to neutralizing antibodies. (LLM, conf=0.91)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    To date, only viral vectors used in gene therapy have been produced by transient transfections for clinical applications.

    “To date, only viral vectors used in gene therapy have been produced by transient transfections for clinical applications (Wright, 2009).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Wright, 2009 source

      The paper’s opening section describes transient transfection-based methods for generating clinical-grade AAV vectors, which are viral vectors used in gene therapy. It does not establish the claim’s exclusivity—that only gene-therapy viral vectors had been produced this way for clinical applications. (LLM, conf=0.85)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Premisecitation

    Human-cl rhFVIII produced in HEK293-F has a similar glycosylation profile to plasma-derived factor VIII and is deprived of α-gal and Neu5Gc.

    “It is produced in HEK293-F cell line and has shown similar glycosylation profile to the plasma-derived factor VIII, deprived of α-gal and Neu5Gc (Casademunt et al., 2012;Kannicht et al., 2013).”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites Casademunt et al., 2012 source

      The Methods and results passage identifies HEK 293 F cells as the source of the rhFVIII, and the Discussion says the product lacks Neu5Gc-type sialic acids and Galα1,3Gal (α-gal). Our copy does not establish that its glycosylation profile is similar to plasma-derived factor VIII; its discussion of an authentic human pattern of post-translational modifications does not make that comparison. No page numbers are available in the indexed passages. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
    • cites Kannicht et al., 2013 source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Because the genome contains numerous sequence repetitions or highly homologous DNA sequences, efforts have been made to improve off-target effects and specificity of ZFN and TALEN enzymes.

    “Because the genome contains numerous sequence repetitions or has highly homologous DNA sequences, efforts have been made in the last years to improve the offtarget effects and the specificity of these enzymes (Miller et al., 2007;Szczepek et al., 2007;Guo et al., 2010;Doyon et al., 2011).”
    Quote in the paperNot a substantial claim2 of 3 sources checked
    • cites Miller et al., 2007 source
    • cites Szczepek et al., 2007 source

      The Results (page not provided) say the authors altered ZFN dimerization to improve cleavage specificity, and the Discussion links ZFN toxicity to off-target cleavage at related DNA sites. The paper does not address TALENs or establish that numerous genomic repetitions or highly homologous sequences motivated this work. (LLM, conf=0.86)

      Experimental — accuracy not yet measured
    • cites Guo et al., 2010 source

      The Discussion says that improving the FokI cleavage domain’s discrimination between highly homologous target sites may increase ZFN specificity and reduce off-target cleavage. It does not address TALENs or establish that numerous genomic repetitions motivated these efforts; the specificity and off-target benefits are framed as possibilities, not demonstrated outcomes. (LLM, conf=0.85)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Different endonucleases employed as second generation tools include zinc finger nucleases (ZFN), meganucleases, TALEN, and CRISPR/Cas9.

    “As second generation tools, different endonucleases have been employed.This category includes zinc finger nucleases (ZFN), meganucleases, transcription activators like effectors nucleases (TALEN) and CRISPR/Cas9 (Durai et al., 2005;Porteus and Carroll 2005;Cabaniols et al., 2010;Silva et al., 2011;Kim et al., 2012;Sanjana et al., 2012;Cho et al., 2013;Sun and Zhao, 2013).”
    Quote in the paperNot a substantial claim1 of 3 sources checked
    • cites Durai et al., 2005 source
    • cites Porteus and Carroll 2005 source
    • cites Cabaniols et al., 2010 source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The PiggyBac transposon system uses an efficient transposase purified from the cabbage looper to integrate the gene of interest into the host genome.

    “Also, the PiggyBac™ (System Bioscience inc.) transposon system uses an efficient transposase purified from the cabbage looper (Trichoplusia ni) to easily integrate the gene of interest into the host genome (Ding et al., 2005).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Ding et al., 2005 source

      The supplied passage and the additional indexed passages have no section or page labels and contain unrelated, repetitive Arabic text. Searches for the cabbage looper, purified transposase, and genomic integration found no passage in our copy that addresses the claim. (LLM, conf=0.78)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Premisecitation

    Expressing rFVIIIFc and rFIXFc in HEK293 resulted in greater tyrosine sulfation and glutamic acid γ-carboxylation compared to CHO cells and excluded α-gal and Neu5Gc from the manufactured products.

    “Expressing these glycoproteins in HEK293 resulted in greater tyrosine sulfation and glutamic acid γ-carboxylation compared to CHO cells and excluded any α-gal and Neu5Gc from the manufactured products (Berkner, 1993;Kannicht et al., 2013;Peters et al., 2013;McCue et al., 2014McCue et al., , 2015)).”
    Quote in the paperSubstantial claim1 of 3 sources checked
    • cites Berkner, 1993 source
    • cites Kannicht et al., 2013 source
    • cites Peters et al., 2013 source

      The Materials and methods section reports that rFVIIIFc was produced in HEK293 cells, and the Results section reports nearly complete tyrosine sulfation. Neither section establishes greater sulfation than in CHO cells. The paper does not substantiate the sentence’s claims about rFIXFc, γ-carboxylation, or exclusion of α-gal and Neu5Gc. (LLM, conf=0.88)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Premisecitation

    An UCOE can prevent DNA methylation of the CMV promoter region, thus preventing gene expression silencing.

    “It has been shown that an UCOE can also prevent DNA methylation of the CMV promoter region, thus preventing gene expression silencing (Lindahl Allen and Antoniou, 2007;Zhang et al., 2010a).”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites Lindahl Allen and Antoniou, 2007 source

      The Introduction reports that the HNRPA2B1-CBX3 UCOE negates DNA-methylation-mediated silencing of hCMV-promoter-driven transgenes in stably transfected tissue-culture cells. It does not specifically say that the UCOE prevents methylation of the CMV promoter region; the paper’s own methylation analysis concerns the HNRPA2B1-CBX3 locus, not that promoter. (LLM, conf=0.85)

      Experimental — accuracy not yet measured
    • cites Zhang et al., 2010a

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Cell cycle progression was faster when using c-myc oncogene in CHO cells.

    “Cell cycle progression was also faster when using c-myc oncogene in CHO cells (Kuystermans and Al-Rubeai, 2009).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Kuystermans and Al-Rubeai, 2009 source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    STAR elements were discovered by a genomic screen of elements that would increase transgene expression.

    “They were discovered by a genomic screen of elements that would increase transgene expression.(Kwaks et al., 2003;Sautter and Enenkel, 2005;Hoeksema et al., 2011;Van Blokland et al., 2011;Harraghy et al., 2015).”
    Quote in the paperNot a substantial claim1 of 3 sources checked
    • cites Kwaks et al., 2003 source
    • cites Sautter and Enenkel, 2005 source
    • cites Hoeksema et al., 2011 source

  • May combine two claims.

    Premisecitation

    MAR and UCOE helped decrease the variability of expression between different clones and contributed to maintaining an active transcriptional state for better transgene expression.

    “It was also demonstrated that MAR and UCOE helped decrease the variability of expression between the different clones and contributed in maintaining an active transcriptional state for better transgene expression (Williams et al., 2005;Galbete et al., 2009;Harraghy et al., 2011).”
    Quote in the paperSubstantial claim1 of 3 sources checked
    • cites Williams et al., 2005 source

      The Results and Discussion report that the CpG-island vectors increased the proportion of expressing clones, and the Conclusion says the findings are consistent with UCOEs maintaining a more open chromatin domain. But the paper does not demonstrate reduced expression variability between clones with the vectors studied; the Conclusion says they showed greater variability than the larger CpG-island construct used in earlier work. This paper studies UCOEs, not MARs. The indexed copy provides section labels but no page numbers. (LLM, conf=0.86)

      Experimental — accuracy not yet measured
    • cites Galbete et al., 2009 source
    • cites Harraghy et al., 2011 source

  • May combine two claims.

    Premisecitation

    Cst-II allows efficient polysialylation by the bacterial polysialyltransferase on recombinant alpha-1-antitrypsin in vitro and this results in a significantly longer half-life in mice, without affecting its specific activity.

    “Cst-II, a bacterial sialyltransferase that can catalyze α2,8 sialylation, allows efficient polysialylation by the bacterial polysialyltransferase on recombinant alpha-1-antitrypsin in vitro and this results in a significantly longer half-life in mice, without affecting its specific activity (Lindhout et al., 2011).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Lindhout et al., 2011 source

      The Abstract describes Cst-II priming A1AT for in vitro polysialylation, and the Results report a longer terminal half-life in mice without adversely affecting its in vitro inhibitory activity. However, the Discussion says the A1AT used was derived from human plasma, not recombinant A1AT. (LLM, conf=0.90)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Premisecitation

    Co-expression of ST6Gal1 and β4GalT1 in HEK293 also helped optimizing sialylation of human Fc-IVIg, therefore enhancing its therapeutic activity.

    “Co-expression of the same enzymes in HEK293 also helped optimizing sialylation of human Fc-IVIg (intravenous immunoglobulin), therefore enhancing its therapeutic activity (Washburn et al., 2015).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Washburn et al., 2015 source

      Materials and Methods says B4GalT1 and ST6Gal1 were produced by transient expression in HEK293 cells, but does not say they were co-expressed. The Results describe using the enzymes in an optimized sialylation reaction, and the Discussion reports enhanced anti-inflammatory activity of the resulting IVIg. The paper therefore supports the enzyme-based sialylation and activity, but not the claimed co-expression mechanism. (LLM, conf=0.88)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Others have tried to reduce the fucosyltransferase level using siRNA.

    “Others have tried to reduce the fucosyltransferase level using siRNA (Imai-Nishiya et al., 2007).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Imai-Nishiya et al., 2007 source

  • May combine two claims.

    Premisecitation

    A bottleneck at the malate dehydrogenase II (MDHII) level was characterized for the tricarboxylic acid (TCA) cycle in CHO cells and pyruvate metabolism was shown to vary between high producing and low producing anti-CD20 CHO clones.

    “A bottleneck at the malate dehydrogenase II (MDHII) level was characterized for the tricarboxylic acid (TCA) cycle in CHO cells and pyruvate metabolism was shown to vary between high producing and low producing anti-CD20 CHO clones (Chong et al., 2010;Ghorbaniaghdam et al., 2014).”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites Chong et al., 2010 source
    • cites Ghorbaniaghdam et al., 2014 source

      The Materials and Methods section identifies the high- and low-producing clones as producers of anti-CD20 antibody. The Discussion reports different pyruvate dehydrogenase and pyruvate carboxylase fluxes between those clones, supporting the pyruvate-metabolism part of the sentence. The passages from this paper do not characterize a TCA-cycle bottleneck at MDHII. (LLM, conf=0.88)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    A first large-scale proteomic analysis identified 6164 proteins from both the proteome and glycoproteome of CHO-K1 cells.

    “A first large-scale proteomic analysis identified 6164 proteins from both the proteome and glycoproteome of CHO-K1 cells (Baycin-Hizal et al., 2012).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Baycin-Hizal et al., 2012 source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Inhibition of the mmu-miR-466 h microRNA was shown to increase apoptosis resistance of these cells.

    “Also, as discussed earlier, inhibition of the mmu-miR-466 h microRNA was shown to increase apoptosis resistance of these cells (Druz et al., 2011;Druz et al., 2013).”
    Quote in the paperNot a substantial claim2 of 2 sources checked
    • cites Druz et al., 2011 source
    • cites Druz et al., 2013 source

  • May combine two claims.

    Premisecitation

    In vitro galactosylation and sialylation of IgG1 Fc glycans did not show any impact on ADCC activity but showed a slight improvement of binding to FcγRIIa.

    “Besides, in vitro galactosylation and sialylation of IgG1 Fc glycans did not show any impact on ADCC activity but showed a slight improvement of binding to FcγRIIa (Thomann et al., 2015).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites Thomann et al., 2015 source

      The Summary of results (Table 2) reports that increased sialylation had no impact on ADCC and that both galactosylation and sialylation increased FcγRIIa binding (slightly in the column assay). But it reports that increased galactosylation increased ADCC activity, contrary to the claim that neither modification affected ADCC. (LLM, conf=0.92)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Premisecitation

    Using the GlycoDelete expression system for transient anti-CD-20 production, recombinant proteins had very short sialylated N-glycans with high homogeneity on the Fc domain and reduced affinity to FcγRs compared to proteins expressed in wild-type 293S.

    “Using this expression system for transient anti-CD-20 production, recombinant proteins had very short sialylated N-glycans with high homogeneity on the Fc domain and reduced affinity to FcγRs compared to proteins expressed in wild-type 293S.”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites Meuris et al., 2014 source

      Split into 2 atoms — 1 confirmed, 1 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

      Experimental — accuracy not yet measured

  • May combine two claims.

    Premisecitation

    CHO cells are involved in the production of over 70% of recombinant biopharmaceutical proteins, most of them monoclonal antibodies.

    “It is involved in the production of over 70% of recombinant biopharmaceutical proteins, most of them being monoclonal antibodies (mAbs) (Durocher and Butler, 2009;Kim et al., 2012;Butler and Spearman, 2014).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Durocher and Butler, 2009 source
    • cites Kim et al., 2012 source
    • cites Butler and Spearman, 2014 source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    A significant portion of approved biopharmaceutical products are recombinant proteins, and the number of them produced in mammalian expression platforms is increasing.

    “A significant portion of these products are recombinant proteins, with an ongoing increase in the number of them produced in mammalian expression platforms (Walsh, 2014).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Walsh, 2014 source

  • May combine two claims.

    Premisecitation

    CHO cells are refractory to infection by human viruses, which minimizes biosafety risks for commercial production.

    “Furthermore, these cells are refractory to infection by human viruses, which minimizes biosafety risks for commercial production purpose (Boeger et al., 2005).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Boeger et al., 2005 source

  • May combine two claims.

    Interpretationcitation

    Using human cell lines for recombinant protein production would favor human-like glycosylation and warrant that proteins harbor at least non-immunogenic glycans.

    “One way to favor human-like glycosylation would be to use human cell lines for recombinant protein production.This strategy would warrant that proteins harbor, if not the ideal glycosylation pattern, at least a non-immunogenic glycans (Swiech et al., 2012).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Swiech et al., 2012 source

  • May combine two claims.

    Premisecitation

    RMCE technology had good success in increasing the success rate and reducing timelines for generation of stable industrial-grade CHO cell lines stably expressing monoclonal antibodies.

    “This technology had good success in increasing the success rate and reducing timelines for the generation of stable industrial-grade CHO cell lines stably expressing monoclonal antibodies (Kito et al., 2002;Huang et al., 2007;Zhang et al., 2015).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Kito et al., 2002 source
    • cites Huang et al., 2007 source
    • cites Zhang et al., 2015 source

  • May combine two claims.

    Interpretationcitation

    Factor VIIa and Factor VIII are abundantly glycosylated and sulfated and are thus challenging to manufacture.

    “These large glycoproteins are abundantly glycosylated and sulfated and are thus challenging to manufacture (Soukharev et al., 2002;Ishaque et al., 2007;Nivitchanyong et al., 2007).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Soukharev et al., 2002 source
    • cites Ishaque et al., 2007 source
    • cites Nivitchanyong et al., 2007 source

  • May combine two claims.

    Premisecitation

    CRISPR/Cas9 has already been validated in CHO cells and reduces production variability between clones.

    “This technique has already been validated in CHO cells and reduces the production variability between clones (Lee et al., 2015b).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Lee et al., 2015b

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Premisecitation

    Conflicting results in the literature have led to the conclusion that MAR activity could be sequence-specific and is influenced by specific vector configuration.

    “However, conflicting results in the literature have led to the conclusion that MAR activity could be sequence-specific and is influenced by specific vector configuration (Harraghy et al., 2015).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Harraghy et al., 2015 source

  • May combine two claims.

    Premisecitation

    Transient expression is ideal for high throughput screening for hits identification and very helpful for early stage product characterization.

    “Yet, it is ideal for high throughput screening for hits identification and very helpful for early stage product characterization (Ozturk and Hu, 2005;Rosser et al., 2005;Rita Costa et al., 2010).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Ozturk and Hu, 2005

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites Rosser et al., 2005 source
    • cites Rita Costa et al., 2010 source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Other selection systems developed more recently include the OSCAR system, which uses minigene vectors encoding hypoxanthine phosphoribosyltransferase (HPRT), essential for purine synthesis.

    “Other selection systems have been developed more recently, such as the OSCAR™ system from the University of Edinburgh, that uses minigene vectors encoding the hypoxanthine phosphoribosyltransferase (HPRT), essential for purine synthesis (Melton et al., 2001;Costa et al., 2012).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Melton et al., 2001 source
    • cites Costa et al., 2012 source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    BHK cells are mostly used for the production of vaccines.

    “Baby Hamster Kidney (BHK) cells are mostly been used for the production of vaccines (Durocher and Butler, 2009).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Durocher and Butler, 2009 source

  • May combine two claims.

    Premisecitation

    Yeast cells produce glycoproteins with high-mannose glycan structures, which may be immunogenic and less potent in humans.

    “However, these cells produce glycoproteins with high-mannose glycans structures, which may be immunogenic and less potent in humans (Dean, 1999;Gemmill and Trimble, 1999;Gerngross, 2004;Dumont et al., 2015).”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites Dean, 1999 source
    • cites Gemmill and Trimble, 1999 source
    • cites Gerngross, 2004 source

  • May combine two claims.

    Interpretationreasoning

    During transient transfection, plasmid DNA is mostly kept extrachromosomally, and cells rapidly lose it during division, limiting the amount of expressed proteins.

    “Indeed, during transient transfection, the plasmid DNA is mostly kept extrachromosomally, the cells rapidly losing it during division, therefore limiting the amount of expressed proteins.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Epoetin delta produced in HT-1080 had better homogeneity of tetra-antennary glycans, higher sialic acid content, and no Neu5Gc compared to CHO-produced erythropoietin.

    “Epoeitin delta produced in HT-1080 was found to have better homogeneity of its tetra-antennary glycans, higher sialic acid content and no Neu5Gc, compared to CHO-produced erythropoietin (Llop et al., 2008).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Llop et al., 2008 source

  • Classified as probably not a substantial claim. May combine two claims.

    Interpretationcitation

    Targeted site gene integration could help biopharmaceutical companies minimize randomness of gene insertion and increase predictability for high transgene expression.

    “This approach could eventually help biopharmaceutical companies minimize the randomness of gene insertion and increase the predictability for high transgene expression (Estes and Melville, 2014).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Estes and Melville, 2014

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationreasoning

    Specific integration may not be a one-size-fits-all approach as some therapeutic proteins may require a particular level of expression to fold properly or acquire adequate quality attributes.

    “One should also keep in mind that such specific integration may not be a one-size-fits-all approach as some therapeutic proteins may require a particular level of expression to fold properly, or to acquire adequate quality attributes (e.g.glycosylation, proteolytic processing, etc.)”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    HKB-11 cells have recently shown high-level protein production and α2,3 and α2,6-sialic acid linkages.

    “It has recently showed high-level protein production and α2,3 and α2,6-sialic acid linkages (Picanco-Castro et al., 2013).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Picanco-Castro et al., 2013 source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationnone given

    ZFN, TALEN and CRISPR/Cas9 technologies are mostly used for gene-specific knockout.

    “ZFN, TALEN and CRISPR/Cas9 technologies are however mostly used for gene-specific knockout.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationcitation

    Although tremendous efforts are required to isolate a highly productive and stable recombination host cell line compared to random integration strategies, targeted integration remains an attractive avenue that should help control and predict expression level of daughter clones.

    “Although tremendous efforts are required to isolate a highly productive and stable recombination host cell line compared to random integration strategies, it remains a very attractive avenue that should help control and predict the expression level of the daughter clones (Estes and Melville, 2014).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Estes and Melville, 2014

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    For production of glycoproteins in large quantities, stable gene expression systems remain the preferred avenue.

    “When it comes to production of glycoproteins in large quantities, stable gene expression systems remain the preferred avenue.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Several recombinases have been used for targeted site approaches, among which Cre/Lox and Flp/FRT were mostly utilized.

    “As first generation tools, several recombinases have been used for targeted site approaches, among which the Cre/Lox and the Flp/FRT were mostly utilized (Kito et al., 2002;Huang et al., 2007;Kim et al., 2012).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Kito et al., 2002 source
    • cites Huang et al., 2007 source
    • cites Kim et al., 2012 source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisenone given

    Some FUT8 knock-out CHO cell lines have been established and one is currently available on the market for glycoprotein productions.

    “Since then, some FUT8 knock-out CHO cell lines have been established and one is currently available on the market for glycoprotein productions.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    CHOK1 hosts have larger endoplasmic reticulum and higher mitochondrial mass compared to DUXB11-derived CHO cells.

    “To explain such discrepancies between studies, it was recently determined that CHOK1 hosts have larger endoplasmic reticulum and higher mitochondrial mass compared to DUXB11-derived CHO cells (Hu et al., 2013).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Hu et al., 2013

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The first FUT8 -/- cell line was created by sequential homologous recombination.

    “The first FUT8 -/-cell line was created by sequential homologous recombination (Yamane-Ohnuki et al., 2004).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Yamane-Ohnuki et al., 2004 source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisenone given

    Yeasts and insect cells can produce high-mannose or paucimannose oligosaccharides, while plant cells introduce undesirable α1,3-fucose and β1,2-xylose.

    “For example, yeasts and insect cells can produce high-mannose or paucimannose oligosaccharides, while plant cells introduce undesirable α1,3-fucose and β1,2-xylose.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Premisenone given

    Both Neu5Gc and α-gal levels are significantly higher in murine cells such as NS0 and Sp2/0, compared to hamster cells.

    “However, both Neu5Gc and α-gal levels are significantly higher in murine cells such as NS0 and Sp2/0, compared to hamster cells.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Although the effects on cell longevity are clear in anti-apoptosis studies, many conflicting results regarding enhanced productivity with anti-apoptosis engineering have been reported.

    “Although the effects on cell longevity are clear in these studies, many conflicting results regarding enhanced productivity with anti-apoptosis engineering have been reported (Kim et al., 2012).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Kim et al., 2012 source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    E2F-1 cell cycle transcription factor overexpression contributes to increase viable cell density in CHO batch cultures.

    “For example, the E2F-1 cell cycle transcription factor overexpression contributes to increase viable cell density in CHO batch cultures (Majors et al., 2008).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Majors et al., 2008 source

  • May combine two claims.

    Interpretationreasoning

    The shift toward protein production favors sustained nutrient availability and reduced secondary metabolite accumulation.

    “This shift toward protein production favors sustained nutrient availability and reduced secondary metabolite accumulation.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Translational and/or post-translational processes might also be rate-limiting for protein production, because of the lack of correlation between gene copy number and the amount of secreted proteins.

    “It has been suggested that translational and/or post-translational processes might also be rate-limiting for protein production, because of the lack of correlation between gene copy number and the amount of secreted proteins (Wilson et al., 1990;Mohan et al., 2008).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Wilson et al., 1990 source
    • cites Mohan et al., 2008 source

  • The quote only partly states this claim.

    Premisenone given

    All anti-apoptosis strategies resulted in increased protein production.

    “All strategies resulted in increased protein production.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    Combining histone deacetylase inhibitors with mild hypothermia (30-32 °C) during production phase or with antiapoptosis cell engineering could also increase productivity.

    “Moreover, combining these inhibitors with mild hypothermia (30-32 °C) during production phase or with antiapoptosis cell engineering could also increase productivity (Kim and Lee, 2000;Kim and Lee, 2002;Sung et al., 2007;Kim et al., 2009a;Chen et al., 2011).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Kim and Lee, 2000 source
    • cites Kim and Lee, 2002 source
    • cites Sung et al., 2007 source

  • May combine two claims.

    Premisecitation

    ATF4 has been overexpressed to restore translation and enhance levels of anti-thrombin III produced in CHO cells.

    “ATF4, another critical transcription factor in the UPR system, has been overexpressed to restore translation and enhance levels of anti-thrombin III produced in CHO cells (Ohya et al., 2008).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Ohya et al., 2008 source

  • May combine two claims.

    Premisecitation

    Overexpression of the mir-17 microRNA in CHO was shown to augment cell proliferation speed, leading to higher Epo-Fc yield.

    “Furthermore, overexpression of the mir-17 microRNA in CHO was shown to augment cell proliferation speed, leading to higher Epo-Fc yield (Jadhav et al., 2012).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Jadhav et al., 2012 source

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

    Premisenone given

    As opposed to human cells, CHO and BHK cells do not express any α2,6-sialyltransferase activity and can generate glycans with terminal Neu5Gc and α-gal.

    “Moreover, as opposed to human cells, CHO and BHK cells do not express any α2,6-sialyltransferase activity and can generate glycans with terminal Neu5Gc and α-gal.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    CHO Lec13 cells and rat hybridoma YB2/0 cells were employed, the former for its impaired synthesis of GDP-fucose and the latter for its reduced expression level of the fucosyltransferase FUT8.

    “As early strategies, CHO Lec13 cells and rat hybridoma YB2/0 cells were employed, the former for its impaired synthesis of GDP-fucose and the latter for its reduced expression level of the fucosyltransferase FUT8 (Durocher and Butler, 2009).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Durocher and Butler, 2009 source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationcitation

    The reduced affinity to FcγRs might be required to increase safety, for example in the context of neutralizing antibodies used for inflammatory cytokine targeting.

    “This reduced affinity might be required to increase safety, for example in the context of neutralizing antibodies used for inflammatory cytokine targeting (Lux et al., 2013).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Lux et al., 2013 source

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Premisenone given

    Glycoengineering strategies have been developed to reduce fucosylation or increase sialylation of biologics.

    “Besides, glycoengineering strategies have been developed to reduce fucosylation or increase sialylation of biologics.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    The tobacco plant Nicotiana benthamiana expression system was genetically modified to carry the human-type sialylation pathway and to generate mono-and disialylated structures with α2,3 and α2,6 linkage.

    “The tobacco plant Nicotiana benthamiana expression system was genetically modified to carry the human-type sialylation pathway and to generate mono-and disialylated structures with α2,3 and α2,6 linkage (Kallolimath et al., 2016).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Kallolimath et al., 2016 source

  • May combine two claims.

    Premisecitation

    Knockouts of 19 glycosyltransferase genes were recently achieved and EPO glycosylation was characterized to measure their impact.

    “In an effort to characterize the contributions of the various glycosylation enzymes in CHO-K1 cells, knockouts of 19 glycosyltransferase genes were recently achieved and EPO glycosylation was characterized to measure their impact (Yang et al., 2015).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Yang et al., 2015 source

  • May combine two claims.

    Premisecitation

    Since expression of GnTIII blocks fucosylation, CHO cells were engineered with both GnTIII and Golgi mannosidase II (ManII) for IgG production.

    “Since expression of the β1,4-mannosyl-glycoprotein 4-β-N-acetylglucosaminyltransferase III (GnTIII) blocks fucosylation, CHO cells were engineered with both GnTIII and Golgi mannosidase II (ManII) for IgG production (Davies et al., 2001;Ferrara et al., 2006).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Davies et al., 2001 source
    • cites Ferrara et al., 2006 source

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    The biopharmaceutical industry has entered the omics era, where systems biology is a central concept.

    “The biopharmaceutical industry has entered the “omics” era, where systems biology is a central concept (Kildegaard et al., 2013).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Kildegaard et al., 2013 source

  • May combine two claims.

    Premisecitation

    The mammalian genomes possess 4 sialidase genes or pseudogenes which are expressed in various cellular compartments.

    “The mammalian genomes possess 4 sialidase genes or pseudogenes (depending on the specie) which are expressed in various cellular compartments (Warner et al., 1993;Ferrari et al., 1994;Zhang et al., 2010b).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Warner et al., 1993 source
    • cites Ferrari et al., 1994 source
    • cites Zhang et al., 2010b

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Interpretationreasoning

    It has become attractive for the industry to produce proteins with optimal sialylation as it could generate substantial savings and confer a therapeutical advantage for the patients.

    “Therefore, it has become attractive for the industry to produce proteins with optimal sialylation as it could generate substantial savings and confer a therapeutical advantage for the patients.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    The anti-CS1 antibody produced with these cells is afucosylated and has enhanced in vitro ADCC activity and in vivo anti-tumor activity compared to the same antibody produced in HEK293 cells.

    “Consequently, the anti-CS1 antibody produced with these cells is afucosylated and has enhanced in vitro ADCC activity and in vivo anti-tumor activity compared to the same antibody produced in HEK293 cells (Gomathinayagam et al., 2015).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Gomathinayagam et al., 2015 source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Using iTRAQ, MCM2 and MCM5 helicases were identified as cell growth markers in CHO cells.

    “Using iTRAQ, MCM2 and MCM5 helicases were identified as cell growth markers in CHO cells (Carlage et al., 2012).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Carlage et al., 2012 source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Chaperones BiP and PDI were differentially expressed in stationary compared to exponential phase in CHO cells overexpressing Bcl-xl.

    “Besides, chaperones BiP and PDI were differentially expressed in stationary compared to exponential phase in CHO cells overexpressing Bcl-xl (Carlage et al., 2012).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Carlage et al., 2012 source
71 of 71

  • The paper relies on this without support.

    Producing more proteins with fewer resources and in less time remains a significant challenge when working with mammalian cell expression systems.

    “Producing more proteins with fewer resources and in less time remains a significant challenge when working with mammalian cell expression systems.”

  • The paper relies on this without support.

    Histone deacetylase inhibitors preserve histone acetylation, reduce their interaction with DNA, and help maintain chromatin in an open configuration, leading to enhanced or prolonged transgene transcription.

    “These histone deacetylase inhibitors, by preserving histones acetylation, reduce their interaction with DNA and helps maintain chromatin in an open configuration, leading to enhanced or prolonged transgene transcription.”

  • The paper relies on this without support.

    Addition of terminal sialic acids on the glycans of protein therapeutics helps to maintain them into the blood circulation by preventing their recognition by the asialoglycoprotein receptors highly expressed in liver hepatocytes.

    “Addition of terminal sialic acids on the glycans of protein therapeutics helps to maintain them into the blood circulation by preventing their recognition by the asialoglycoprotein receptors highly expressed in liver hepatocytes.”

  • The paper relies on this without support.

    Mammalian cell lines, in particular CHO cells, are now extensively used for production of therapeutic glycoproteins by the biopharmaceutical industry.

    “Mammalian cell lines, in particular CHO cells, are now extensively used for production of therapeutic glycoproteins by the biopharmaceutical industry.”

  • The paper relies on this without support.

    These cells possess many advantages in terms of cell culture and have the capacity to generate high titers.

    “These cells possess many advantages in terms of cell culture and have the capacity to generate high titers.”

  • The paper relies on this without support.

    Another limitation of glycoprotein production is the proper folding of the desired biologics.

    “Another limitation of glycoprotein production is the proper folding of the desired biologics.”

  • The paper relies on this without support.

    Chaperones play a key role in the folding process of nascent proteins.

    “Chaperones play a key role in the folding process of nascent proteins.”

  • The paper relies on this without support.

    Combining all omics data using computational models will help broaden understanding and improve the various expression systems used by the biopharmaceutical industry for glycoprotein production.

    “Yet, combining all “omics” data using computational models will help broaden our understanding and improve the various expression systems used by the biopharmaceutical industry for glycoprotein production.”
8 of 8

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Plant-specific glycan is identified as both fructose and fucose

    Minor

    The paper gives two different names for the plant-specific α1,3-linked sugar: fructose in Section 2.4 and fucose in Section 4.

1 of 1

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Authors
Lalonde, M.-E., & Durocher, Y.
Affiliations
  • Université de Montréal (CA)
  • National Research Council Canada (CA)
Corresponding author
Durocher, Yves
ORCID
Durocher, Yves
Venue
Journal of Biotechnology
Publisher
Elsevier BV
Published
2017-06
Volume
251
Pages
128-140
ISSN
0168-1656 (ISSN-L)
DOI
10.1016/j.jbiotec.2017.04.028
OpenAlex
W2608656888
Semantic Scholar
d121382e44037491f896fe3ef571c7ee21b21b3a
Cited by
296
References
257
Citations by year
2026: 19 · 2025: 19 · 2024: 29 · 2023: 34 · 2022: 31 · 2021: 34 · 2020: 40 · 2019: 58 · 2018: 25 · 2017: 5 · 2013: 1
FWCI
3.28
Type
journal article
Language
en
Open access
Licence
Locations
  • Journal of Biotechnology (publishedVersion, cc-by-nc-nd)
  • PubMed (publishedVersion)
  • NPARC (submittedVersion)
Funders
CIHR (Canadian Institutes of Health Research) fellowship
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Viral Infectious Diseases and Gene Expression in Insects
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Protein purification and stability
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Glycosylation and Glycoproteins Research
Keywords
therapeutic glycoproteins, mammalian cell expression systems, glycosylation, monoclonal antibodies, glycan profiles, cell engineering, CHO cells, recombinant protein expression, biopharmaceuticals, omics technologies
MeSH terms
Animals, Cell Line, Glycoproteins, Humans, Recombinant Proteins, Genomics, Cell Engineering

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-10-30.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-10-30.

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Statistics and arithmetic are recomputed, not judged.

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