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Chongsaritsinsuk J, Rangel-Angarita V, Mahoney KE, Lucas TM, Enny OM, Katemauswa M, Malaker SA. Quantification and site-specific analysis of co-occupied N- and O-glycopeptides. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.06.602348. [PMID: 39005468 PMCID: PMC11245114 DOI: 10.1101/2024.07.06.602348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/16/2024]
Abstract
Protein glycosylation is a complex post-translational modification that is generally classified as N- or O-linked. Site-specific analysis of glycopeptides is accomplished with a variety of fragmentation methods, depending on the type of glycosylation being investigated and the instrumentation available. For instance, collisional dissociation methods are frequently used for N-glycoproteomic analysis with the assumption that one N-sequon exists per tryptic peptide. Alternatively, electron-based methods are indispensable for O-glycosite localization. However, the presence of simultaneously N- and O-glycosylated peptides could suggest the necessity of electron-based fragmentation methods for N-glycoproteomics, which is not commonly performed. Thus, we quantified the prevalence of N- and O-glycopeptides in mucins and other glycoproteins. A much higher frequency of co-occupancy within mucins was detected whereas only a negligible occurrence occurred within non-mucin glycoproteins. This was demonstrated from analyses of recombinant and/or purified proteins, as well as more complex samples. Where co-occupancy occurred, O-glycosites were frequently localized to the Ser/Thr within the N-sequon. Additionally, we found that O-glycans in close proximity to the occupied Asn were predominantly unelaborated core 1 structures, while those further away were more extended. Overall, we demonstrate electron-based methods are required for robust site-specific analysis of mucins, wherein co-occupancy is more prevalent. Conversely, collisional methods are generally sufficient for analyses of other types of glycoproteins.
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Lunghi B, Morfini M, Martinelli N, Branchini A, Linari S, Castaman G, Bernardi F. Modulation of factor VIII pharmacokinetics by genetic components in factor VIII receptors. Haemophilia 2023; 29:479-487. [PMID: 36533781 DOI: 10.1111/hae.14722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 11/18/2022] [Accepted: 11/29/2022] [Indexed: 12/23/2022]
Abstract
INTRODUCTION Gene variation in receptors for circulating factor VIII (FVIII) is candidate to explain the large inter-patient variability of infused FVIII pharmacokinetics (PK) in haemophilia A (HA). AIM To compare in an Italian HA cohort (n = 26) the influence on FVIII PK of genetic components in four von Willebrand factor (VWF)/FVIII receptors. METHODS Genotypes of low-density lipoprotein receptor (LDLR), asialoglycoprotein receptor minor subunit (ASGR2), family 4 member M (CLEC4M), stabilin2 (STAB2) and ABO blood-group, and VWF:Ag levels were included as independent variables in linear regression analyses of two-compartment model (TCM) - standard half-life (SHL) FVIII PK parameters. RESULTS In the initial FVIII distribution phase, the STAB2 rs4981022 AA, ASGR2 rs2289645 TT and LDLR rs688 TT genotypes may contribute to increase Cmax , and prolong or shorten AlphaHL. In the elimination phase, a shorter BetaHL was associated with the CLEC4M rs868875 GG (beta-coefficient .366, p = .025) and ASGR2 rs2289645 TC (beta-coefficient .456, p = .006) genotypes, which also showed shorter mean residence time (MRT) than TT genotypes (p = .021). The alpha and beta phase effects were independent of ABO and VWF:Ag levels at baseline. The association of the LDLR rs2228671 genotypes with clearance was independent of ABO (beta-coefficient -.363, p = .035) but not of other receptors or VWF:Ag, which may point out multiple and competing interactions. CONCLUSIONS With the limitation of the small number of HA patients, these observations highlight multiple genetic components acting in distinct phases of FVIII PK and contributing to explain FVIII PK variability. This analysis provides candidates for genotype-based, individual tailoring of FVIII substitutive treatment.
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Affiliation(s)
- Barbara Lunghi
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Massimo Morfini
- Italian Association of Hemophilia Centers (AICE), Naples, Italy
| | | | - Alessio Branchini
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Silvia Linari
- Center for Bleeding Disorders, Department of Oncology, Careggi University Hospital, Florence, Italy
| | - Giancarlo Castaman
- Center for Bleeding Disorders, Department of Oncology, Careggi University Hospital, Florence, Italy
| | - Francesco Bernardi
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
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Manz XD, Bogaard HJ, Aman J. Regulation of VWF (Von Willebrand Factor) in Inflammatory Thrombosis. Arterioscler Thromb Vasc Biol 2022; 42:1307-1320. [PMID: 36172866 DOI: 10.1161/atvbaha.122.318179] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Increasing evidence indicates that inflammation promotes thrombosis via a VWF (von Willebrand factor)-mediated mechanism. VWF plays an essential role in maintaining the balance between blood coagulation and bleeding, and inflammation can lead to aberrant regulation. VWF is regulated on a transcriptional and (post-)translational level, and its secretion into the circulation captures platelets upon endothelial activation. The significant progress that has been made in understanding transcriptional and translational regulation of VWF is described in this review. First, we describe how VWF is regulated at the transcriptional and post-translational level with a specific focus on the influence of inflammatory and immune responses. Next, we describe how changes in regulation are linked with various cardiovascular diseases. Recent insights from clinical diseases provide evidence for direct molecular links between inflammation and thrombosis, including atherosclerosis, chronic thromboembolic pulmonary hypertension, and COVID-19. Finally, we will briefly describe clinical implications for antithrombotic treatment.
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Affiliation(s)
- Xue D Manz
- Department of Pulmonary Medicine, Amsterdam UMC, VU University Medical Center, Amsterdam Cardiovascular Sciences (ACS), the Netherlands
| | - Harm Jan Bogaard
- Department of Pulmonary Medicine, Amsterdam UMC, VU University Medical Center, Amsterdam Cardiovascular Sciences (ACS), the Netherlands
| | - Jurjan Aman
- Department of Pulmonary Medicine, Amsterdam UMC, VU University Medical Center, Amsterdam Cardiovascular Sciences (ACS), the Netherlands
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Ward SE, O'Sullivan JM, Moran AB, Spencer DIR, Gardner RA, Sharma J, Fazavana J, Monopoli M, McKinnon TAJ, Chion A, Haberichter S, O'Donnell JS. Sialylation on O-linked glycans protects von Willebrand factor from macrophage galactose lectin-mediated clearance. Haematologica 2022; 107:668-679. [PMID: 33763999 PMCID: PMC8883566 DOI: 10.3324/haematol.2020.274720] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 03/12/2021] [Indexed: 11/17/2022] Open
Abstract
Terminal sialylation determines the plasma half-life of von Willebrand factor (VWF). A role for macrophage galactose lectin (MGL) in regulating hyposialylated VWF clearance has recently been proposed. In this study, we showed that MGL influences physiological plasma VWF clearance. MGL inhibition was associated with a significantly extended mean residence time and 3-fold increase in endogenous plasma VWF antigen levels (P<0.05). Using a series of VWF truncations, we further demonstrated that the A1 domain of VWF is predominantly responsible for enabling the MGL interaction. Binding of both full-length and VWF-A1-A2-A3 to MGL was significantly enhanced in the presence of ristocetin (P<0.05), suggesting that the MGL-binding site in A1 is not fully accessible in globular VWF. Additional studies using different VWF glycoforms demonstrated that VWF O-linked glycans, clustered at either end of the A1 domain, play a key role in protecting VWF against MGLmediated clearance. Reduced sialylation has been associated with pathological, increased clearance of VWF in patients with von Willebrand disease. Herein, we demonstrate that specific loss of α2-3 linked sialylation from O-glycans results in markedly increased MGL-binding in vitro, and markedly enhanced MGL-mediated clearance of VWF in vivo. Our data further show that the asialoglycoprotein receptor (ASGPR) does not have a significant role in mediating the increased clearance of VWF following loss of O-sialylation. Conversely however, we observed that loss of N-linked sialylation from VWF drives enhanced circulatory clearance predominantly via the ASGPR. Collectively, our data support the hypothesis that in addition to regulating physiological VWF clearance, the MGL receptor works in tandem with ASGPR to modulate enhanced clearance of aberrantly sialylated VWF in the pathogenesis of von Willebrand disease.
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Affiliation(s)
- Soracha E Ward
- Irish Centre for Vascular Biology, School of Pharmacy and Biomolecular Sciences, Royal College of Surgeons in Ireland
| | - Jamie M O'Sullivan
- Irish Centre for Vascular Biology, School of Pharmacy and Biomolecular Sciences, Royal College of Surgeons in Ireland
| | - Alan B Moran
- Ludger, Ltd., Culham Science Centre, Abingdon, Oxfordshire OX14 3EB, United Kingdom; Leiden University Medical Centre, Centre for Proteomics and Metabolomics, 2300 RC Leiden
| | | | | | - Jyotika Sharma
- Department of Basic Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, North Dakota
| | - Judicael Fazavana
- Irish Centre for Vascular Biology, School of Pharmacy and Biomolecular Sciences, Royal College of Surgeons in Ireland
| | - Marco Monopoli
- Department of Chemistry, RCSI, 123 St. Stephen's Green, Dublin 2
| | - Thomas A J McKinnon
- Faculty of Medicine, Imperial College, Hammersmith Hospital, Ducane Road, London
| | - Alain Chion
- Irish Centre for Vascular Biology, School of Pharmacy and Biomolecular Sciences, Royal College of Surgeons in Ireland
| | | | - James S O'Donnell
- Irish Centre for Vascular Biology, School of Pharmacy and Biomolecular Sciences, Royal College of Surgeons in Ireland; National Children's Research Centre, Our Lady's Children's Hospital, Dublin, Ireland; National Coagulation Centre, St James's Hospital, Dublin.
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Combination of CLEC4M rs868875 G-Carriership and ABO O Genotypes May Predict Faster Decay of FVIII Infused in Hemophilia A Patients. J Clin Med 2022; 11:jcm11030733. [PMID: 35160186 PMCID: PMC8837058 DOI: 10.3390/jcm11030733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 01/21/2022] [Accepted: 01/27/2022] [Indexed: 11/26/2022] Open
Abstract
The C-type lectin CLEC4M binds and internalizes factor VIII (FVIII). Common CLEC4M variants have been associated with FVIII pharmacokinetic (PK) profiles in hemophilia A (HA) patients. The two-compartment PK analysis of plasma-derived (pd-) and full length recombinant FVIII concentrates was conducted in twenty-six patients (FVIII:C ≤ 2 IU/dL). F8, ABO blood-groups, and the CLEC4M rs868875A/G polymorphism were genotyped. CLEC4M genotype groups differed for the elimination rate constant K 1-0 (p < 0.001), half-life (K 1-0 HL), and the Beta rate constant. Patients treated with pd-FVIII also differed in the Alpha phase. In linear regression models, the contribution of the CLEC4M genotypes to FVIII PK parameters remained significant after correction for ABO, age, and VWF antigen levels at PK. Combined CLEC4M rs868875A/G and ABO genotypes displayed significant interaction (K 1-0, p = 0.014). Compared to other combined genotypes, the G-carriers/O genotypes showed half-reduced K 1-0 HL (p = 0.008), and faster FVIII clearance (mean 7.1 ± 2.2 mL/h/kg SE) than in the G-carriers/non-O (mean 2.4 ± 0.3 mL/h/kg SE), (p = 0.038). Comparison in HA patients recruited in several countries suggests that CLEC4M genotypes coherently influence infused FVIII half-life and clearance. Our analysis supports substantially faster FVIII decay associated with the rs868875 G-carrier/ABO O genotypes, which has potential implications for genetically tailored substitutive HA treatment.
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Ward S, O'Sullivan JM, O'Donnell JS. The Biological Significance of von Willebrand Factor O-Linked Glycosylation. Semin Thromb Hemost 2021; 47:855-861. [PMID: 34130346 DOI: 10.1055/s-0041-1726373] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Glycosylation is a key posttranslational modification, known to occur on more than half of all secreted proteins in man. As such, the role of N- and O-linked glycan structures in modulating various aspects of protein biology is an area of much research. Given their prevalence, it is perhaps unsurprising that variations in glycan structures have been demonstrated to play critical roles in modulating protein function and have been implicated in the pathophysiology of human diseases. von Willebrand factor (VWF), a plasma glycoprotein that is essential for normal hemostasis, is heavily glycosylated, containing 13 N-linked and 10 O-linked glycans. Together, these carbohydrate chains account for 20% of VWF monomeric mass, and have been shown to modulate VWF structure, function, and half-life. In this review, we focus on the specific role played by O-linked glycans in modulating VWF biology. Specifically, VWF O-linked glycans have been shown to modulate tertiary protein structure, susceptibility to ADAMTS13 proteolysis, platelet tethering, and VWF circulatory half-life.
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Affiliation(s)
- Soracha Ward
- Haemostasis Research Group, Irish Centre for Vascular Biology, School of Pharmacy and Bimolecular Sciences, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Jamie M O'Sullivan
- Haemostasis Research Group, Irish Centre for Vascular Biology, School of Pharmacy and Bimolecular Sciences, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - James S O'Donnell
- Haemostasis Research Group, Irish Centre for Vascular Biology, School of Pharmacy and Bimolecular Sciences, Royal College of Surgeons in Ireland, Dublin, Ireland.,National Coagulation Centre, St James's Hospital, Dublin, Ireland
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The relationship between ABO blood group, von Willebrand factor, and primary hemostasis. Blood 2021; 136:2864-2874. [PMID: 32785650 DOI: 10.1182/blood.2020005843] [Citation(s) in RCA: 67] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Accepted: 08/03/2020] [Indexed: 12/16/2022] Open
Abstract
Numerous studies have reported significant associations between ABO blood group and risk of cardiovascular disease. These studies have consistently demonstrated that thrombotic risk is significantly reduced in individuals in blood group O. Nevertheless, the biological mechanisms through which ABO influences hemostasis have remained poorly understood. Exciting recent data have provided novel insights into how these ABO effects are modulated and have highlighted that ABO group significantly influences platelet plug formation at sites of vascular injury (primary hemostasis). In particular, ABO affects multiple aspects of von Willebrand factor (VWF) biology. In keeping with their reduced thrombotic risk, plasma VWF levels are ∼25% lower in healthy group O compared with healthy group non-O individuals. In addition, blood group O VWF demonstrates enhanced susceptibility to ADAMTS13 proteolysis. Finally, preliminary findings suggest that the interaction of group O VWF with platelets may also be reduced. Although the molecular mechanisms underlying these ABO effects on VWF have not been fully elucidated, it seems likely that they are mediated in large part by the ABO(H) carbohydrate structures that are carried on both the N- and O-linked glycans of VWF. Interestingly, ABO(H) determinants are also expressed on several different platelet surface glycoprotein receptors. Recent studies support the hypothesis that ABO group not only exerts major quantitative and qualitative effects on VWF, but also affect specific aspects of platelet function. Given the severe morbidity and the mortality associated with thrombotic disorders, defining the mechanisms underlying these ABO effects is not only of scientific interest, but also of direct clinical importance.
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Ma C, Liu D, Li D, Zhang J, Xu XQ, Zhu H, Wan XF, Miao CH, Konkle BA, Onigman P, Xiao W, Li L. Comprehensive N- and O-glycosylation mapping of human coagulation factor V. J Thromb Haemost 2020; 18:1884-1892. [PMID: 32310329 PMCID: PMC7732234 DOI: 10.1111/jth.14861] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Revised: 04/08/2020] [Accepted: 04/10/2020] [Indexed: 12/22/2022]
Abstract
BACKGROUND/OBJECTIVE Coagulation factor V (FV), a multidomain glycoprotein, is an essential cofactor in the blood clotting cascade. FV deficiency is a rare bleeding disorder that results in poor clotting after an injury or surgery. The only treatment for the disease is infusions of fresh frozen plasma and blood platelets. Glycosylation affects the biological activity, pharmacokinetics, immunogenicity, and in vivo clearance rate of proteins in the plasma. The glycan profile of FV, as well as how it affects the activity, stability, and immunogenicity, remains unknown. METHODS In this study, we comprehensively mapped the glycosylation patterns of human plasma-derived FV by combining multienzyme digestion, hydrophilic interaction chromatography enrichment of glycopeptides, and alternated fragmentation mass spectrometry analysis. RESULTS/CONCLUSION A total of 57 unique N-glycopeptides and 51 O-glycopeptides were identified, which were categorized into 40 N-glycan and 17 O-glycan compositions. Such glycosylation details are fundamental for future functional studies and therapeutics development. In addition, the established methodology can be readily applied to analyze glycosylation patterns of proteins with more than 2000 amino acids.
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Affiliation(s)
- Cheng Ma
- Department of Chemistry, Georgia State University, Atlanta, GA, USA
| | - Ding Liu
- Department of Chemistry, Georgia State University, Atlanta, GA, USA
| | - Dong Li
- Department of Clinical Laboratory, Shanghai Tongji Hospital, Tongji University School of Medicine, Shanghai, China
| | - Junping Zhang
- Department of Microbiology and Immunology, Sol Sherry Thrombosis Research Center, Cardiovascular Research Center, Temple University, Philadelphia, PA, USA
| | - Xiao-Qian Xu
- Department of Hematology, Shanghai Jiaotong University Affiliated Shanghai General Hospital, Shanghai, China
| | - He Zhu
- Department of Chemistry, Georgia State University, Atlanta, GA, USA
| | - Xiu-Feng Wan
- Missouri University Center for Research on Influenza Systems Biology (CRISB), University of Missouri, Columbia, MO, USA
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO, USA
- Department of Electrical Engineering & Computer Science, College of Engineering, University of Missouri, Columbia, MO, USA
- Bond Life Sciences Center, University of Missouri, Columbia, MO, USA
- MU Informatics Institute, University of Missouri, Columbia, MO, USA
- Department of Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA
| | - Carol H. Miao
- Center for Immunity and Immunotherapies, Seattle Children’s Research Institute, Seattle, WA, USA
- University of Washington, Seattle, WA, USA
| | - Barbara A. Konkle
- University of Washington, Seattle, WA, USA
- Bloodworks Northwest, Seattle, WA, USA
| | | | - Weidong Xiao
- Department of Microbiology and Immunology, Sol Sherry Thrombosis Research Center, Cardiovascular Research Center, Temple University, Philadelphia, PA, USA
| | - Lei Li
- Department of Chemistry, Georgia State University, Atlanta, GA, USA
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Advances toward mapping the full extent of protein site-specific O-GalNAc glycosylation that better reflects underlying glycomic complexity. Curr Opin Struct Biol 2019; 56:146-154. [DOI: 10.1016/j.sbi.2019.02.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 02/04/2019] [Accepted: 02/13/2019] [Indexed: 01/01/2023]
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10
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Increased galactose expression and enhanced clearance in patients with low von Willebrand factor. Blood 2019; 133:1585-1596. [DOI: 10.1182/blood-2018-09-874636] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Accepted: 02/06/2019] [Indexed: 11/20/2022] Open
Abstract
Abstract
Glycan determinants on von Willebrand factor (VWF) play critical roles in regulating its susceptibility to proteolysis and clearance. Abnormal glycosylation has been shown to cause von Willebrand disease (VWD) in a number of different mouse models. However, because of the significant technical challenges associated with accurate assessment of VWF glycan composition, the importance of carbohydrates in human VWD pathogenesis remains largely unexplored. To address this, we developed a novel lectin-binding panel to enable human VWF glycan characterization. This methodology was then used to study glycan expression in a cohort of 110 patients with low VWF compared with O blood group-matched healthy controls. Interestingly, significant interindividual heterogeneity in VWF glycan expression was seen in the healthy control population. This variation included terminal sialylation and ABO(H) blood group expression on VWF. Importantly, we also observed evidence of aberrant glycosylation in a subgroup of patients with low VWF. In particular, terminal α(2-6)-linked sialylation was reduced in patients with low VWF, with a secondary increase in galactose (Gal) exposure. Furthermore, an inverse correlation between Gal exposure and estimated VWF half-life was observed in those patients with enhanced VWF clearance. Together, these findings support the hypothesis that loss of terminal sialylation contributes to the pathophysiology underpinning low VWF in at least a subgroup of patients by promoting enhanced clearance. In addition, alterations in VWF carbohydrate expression are likely to contribute to quantitative and qualitative variations in VWF levels in the normal population. This trial was registered at www.clinicaltrials.gov as #NCT03167320.
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Site-Specific N-Glycosylation on the AAV8 Capsid Protein. Viruses 2018; 10:v10110644. [PMID: 30453606 PMCID: PMC6266768 DOI: 10.3390/v10110644] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 11/05/2018] [Accepted: 11/15/2018] [Indexed: 12/13/2022] Open
Abstract
Adeno associated virus (AAV) is a versatile gene delivery tool, which has been approved as a human gene therapy vector for combating genetic diseases. AAV capsid proteins are the major components that determine the tissue specificity, immunogenicity and in vivo transduction performance of the vector. In this study, the AAV8 capsid glycosylation profile was systemically analyzed by peptide mass fingerprinting utilizing high-resolution mass spectrometry to determine the presence of capsid glycosylation. We identified N-glycosylation on the amino acid N499 of the capsid protein. We characterized the overall sugar profile for vector produced in 293 cells. Multiple N-glycosylated host-cell proteins (HCPs) copurified with AAV8 vectors and were identified by analyzing LC-MS data utilizing a human database and proteome discoverer search engine. The N-glycosylation analysis by MALDI-TOF MS, highlighted the probability of AAV8 interaction with terminal galactosylated N-glycans within the HCPs.
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