1
|
Sudol ASL, Crispin M, Tews I. The IgG-specific endoglycosidases EndoS and EndoS2 are distinguished by conformation and antibody recognition. J Biol Chem 2024; 300:107245. [PMID: 38569940 PMCID: PMC11063906 DOI: 10.1016/j.jbc.2024.107245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 03/19/2024] [Accepted: 03/25/2024] [Indexed: 04/05/2024] Open
Abstract
The IgG-specific endoglycosidases EndoS and EndoS2 from Streptococcus pyogenes can remove conserved N-linked glycans present on the Fc region of host antibodies to inhibit Fc-mediated effector functions. These enzymes are therefore being investigated as therapeutics for suppressing unwanted immune activation, and have additional application as tools for antibody glycan remodeling. EndoS and EndoS2 differ in Fc glycan substrate specificity due to structural differences within their catalytic glycosyl hydrolase domains. However, a chimeric EndoS enzyme with a substituted glycosyl hydrolase from EndoS2 loses catalytic activity, despite high structural homology between the two enzymes, indicating either mechanistic divergence of EndoS and EndoS2, or improperly-formed domain interfaces in the chimeric enzyme. Here, we present the crystal structure of the EndoS2-IgG1 Fc complex determined to 3.0 Å resolution. Comparison of complexed and unliganded EndoS2 reveals relative reorientation of the glycosyl hydrolase, leucine-rich repeat and hybrid immunoglobulin domains. The conformation of the complexed EndoS2 enzyme is also different when compared to the earlier EndoS-IgG1 Fc complex, and results in distinct contact surfaces between the two enzymes and their Fc substrate. These findings indicate mechanistic divergence of EndoS2 and EndoS. It will be important to consider these differences in the design of IgG-specific enzymes, developed to enable customizable antibody glycosylation.
Collapse
Affiliation(s)
- Abigail S L Sudol
- School of Biological Sciences, University of Southampton, Southampton, UK
| | - Max Crispin
- School of Biological Sciences, University of Southampton, Southampton, UK.
| | - Ivo Tews
- School of Biological Sciences, University of Southampton, Southampton, UK.
| |
Collapse
|
2
|
Happonen L, Collin M. Immunomodulating Enzymes from Streptococcus pyogenes-In Pathogenesis, as Biotechnological Tools, and as Biological Drugs. Microorganisms 2024; 12:200. [PMID: 38258026 PMCID: PMC10818452 DOI: 10.3390/microorganisms12010200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 01/12/2024] [Accepted: 01/16/2024] [Indexed: 01/24/2024] Open
Abstract
Streptococcus pyogenes, or Group A Streptococcus, is an exclusively human pathogen that causes a wide variety of diseases ranging from mild throat and skin infections to severe invasive disease. The pathogenesis of S. pyogenes infection has been extensively studied, but the pathophysiology, especially of the more severe infections, is still somewhat elusive. One key feature of S. pyogenes is the expression of secreted, surface-associated, and intracellular enzymes that directly or indirectly affect both the innate and adaptive host immune systems. Undoubtedly, S. pyogenes is one of the major bacterial sources for immunomodulating enzymes. Major targets for these enzymes are immunoglobulins that are destroyed or modified through proteolysis or glycan hydrolysis. Furthermore, several enzymes degrade components of the complement system and a group of DNAses degrade host DNA in neutrophil extracellular traps. Additional types of enzymes interfere with cellular inflammatory and innate immunity responses. In this review, we attempt to give a broad overview of the functions of these enzymes and their roles in pathogenesis. For those enzymes where experimentally determined structures exist, the structural aspects of the enzymatic activity are further discussed. Lastly, we also discuss the emerging use of some of the enzymes as biotechnological tools as well as biological drugs and vaccines.
Collapse
Affiliation(s)
- Lotta Happonen
- Faculty of Medicine, Department of Clinical Sciences, Division of Infection Medicine, Lund University, SE-22184 Lund, Sweden
| | - Mattias Collin
- Faculty of Medicine, Department of Clinical Sciences, Division of Infection Medicine, Lund University, SE-22184 Lund, Sweden
| |
Collapse
|
3
|
García-Alija M, van Moer B, Sastre DE, Azzam T, Du JJ, Trastoy B, Callewaert N, Sundberg EJ, Guerin ME. Modulating antibody effector functions by Fc glycoengineering. Biotechnol Adv 2023; 67:108201. [PMID: 37336296 PMCID: PMC11027751 DOI: 10.1016/j.biotechadv.2023.108201] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 06/09/2023] [Accepted: 06/16/2023] [Indexed: 06/21/2023]
Abstract
Antibody based drugs, including IgG monoclonal antibodies, are an expanding class of therapeutics widely employed to treat cancer, autoimmune and infectious diseases. IgG antibodies have a conserved N-glycosylation site at Asn297 that bears complex type N-glycans which, along with other less conserved N- and O-glycosylation sites, fine-tune effector functions, complement activation, and half-life of antibodies. Fucosylation, galactosylation, sialylation, bisection and mannosylation all generate glycoforms that interact in a specific manner with different cellular antibody receptors and are linked to a distinct functional profile. Antibodies, including those employed in clinical settings, are generated with a mixture of glycoforms attached to them, which has an impact on their efficacy, stability and effector functions. It is therefore of great interest to produce antibodies containing only tailored glycoforms with specific effects associated with them. To this end, several antibody engineering strategies have been developed, including the usage of engineered mammalian cell lines, in vitro and in vivo glycoengineering.
Collapse
Affiliation(s)
- Mikel García-Alija
- Structural Glycobiology Laboratory, Biocruces Health Research Institute, Barakaldo, Bizkaia 48903, Spain
| | - Berre van Moer
- VIB Center for Medical Biotechnology, VIB, Zwijnaarde, Technologiepark 71, 9052 Ghent (Zwijnaarde), Belgium; Department of Biochemistry and Microbiology, Ghent University, Technologiepark 71, 9052 Ghent (Zwijnaarde), Belgium
| | - Diego E Sastre
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Tala Azzam
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Jonathan J Du
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Beatriz Trastoy
- Structural Glycoimmunology Laboratory, Biocruces Health Research Institute, Barakaldo, Bizkaia, 48903, Spain; Ikerbasque, Basque Foundation for Science, 48009 Bilbao, Spain.
| | - Nico Callewaert
- VIB Center for Medical Biotechnology, VIB, Zwijnaarde, Technologiepark 71, 9052 Ghent (Zwijnaarde), Belgium; Department of Biochemistry and Microbiology, Ghent University, Technologiepark 71, 9052 Ghent (Zwijnaarde), Belgium.
| | - Eric J Sundberg
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, USA.
| | - Marcelo E Guerin
- Structural Glycobiology Laboratory, Biocruces Health Research Institute, Barakaldo, Bizkaia 48903, Spain; Ikerbasque, Basque Foundation for Science, 48009 Bilbao, Spain.
| |
Collapse
|
4
|
Gedi V, Duarte F, Patel P, Bhattacharjee P, Tecza M, McGourty K, Hudson SP. Impact of Propeptide Cleavage on the Stability and Activity of a Streptococcal Immunomodulatory C5a Peptidase for Biopharmaceutical Development. Mol Pharm 2023; 20:4041-4049. [PMID: 37406301 PMCID: PMC10410607 DOI: 10.1021/acs.molpharmaceut.3c00207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 06/18/2023] [Accepted: 06/20/2023] [Indexed: 07/07/2023]
Abstract
Posttranslational modifications of proteins can impact their therapeutic efficacy, stability, and potential for pharmaceutical development. The Group AStreptococcus pyogenesC5a peptidase (ScpA) is a multi-domain protein composed of an N-terminal signal peptide, a catalytic domain (including propeptide), three fibronectin domains, and cell membrane-associated domains. It is one of several proteins produced by Group AS. pyogenesknown to cleave components of the human complement system. After signal peptide removal, ScpA undergoes autoproteolysis and cleaves its propeptide for full maturation. The exact location and mechanism of the propeptide cleavage, and the impact of this cleavage on stability and activity, are not clearly understood, and the exact primary sequence of the final enzyme is not known. A form of ScpA with no autoproteolysis fragments of propeptide present may be more desirable for pharmaceutical development from a regulatory and a biocompatibility in the body perspective. The current study describes an in-depth structural and functional characterization of propeptide truncated variants of ScpA expressed inEscherichia colicells. All three purified ScpA variants, ScpA, 79ΔPro, and 92ΔPro, starting with N32, D79, and A92 positions, respectively, showed similar activity against C5a, which suggests a propeptide-independent activity profile of ScpA. CE-SDS and MALDI top-down sequencing analyses highlight a time-dependent propeptide autoproteolysis of ScpA at 37 °C with a distinct end point at A92 and/or D93. In comparison, all three variants of ScpA exhibit similar stability, melting temperatures, and secondary structure orientation. In summary, this work not only highlights propeptide localization but also provides a strategy to recombinantly produce a final mature and active form of ScpA without any propeptide-related fragments.
Collapse
Affiliation(s)
- Vinayakumar Gedi
- Department
of Chemical Sciences, Bernal Institute, University of Limerick, Limerick V94 T9PX, Ireland
| | - Francisco Duarte
- Department
of Chemical Sciences, Bernal Institute, University of Limerick, Limerick V94 T9PX, Ireland
| | - Pratikkumar Patel
- Department
of Chemical Sciences, Bernal Institute, University of Limerick, Limerick V94 T9PX, Ireland
| | - Promita Bhattacharjee
- Department
of Chemical Sciences, Bernal Institute, University of Limerick, Limerick V94 T9PX, Ireland
| | - Malgorzata Tecza
- Department
of Chemical Sciences, Bernal Institute, University of Limerick, Limerick V94 T9PX, Ireland
| | - Kieran McGourty
- Department
of Chemical Sciences, Bernal Institute, University of Limerick, Limerick V94 T9PX, Ireland
- SSPC
SFI Research Centre for Pharmaceuticals, University of Limerick, Limerick V94 T9PX, Ireland
| | - Sarah P. Hudson
- Department
of Chemical Sciences, Bernal Institute, University of Limerick, Limerick V94 T9PX, Ireland
- SSPC
SFI Research Centre for Pharmaceuticals, University of Limerick, Limerick V94 T9PX, Ireland
| |
Collapse
|
5
|
Chia S, Tay SJ, Song Z, Yang Y, Walsh I, Pang KT. Enhancing pharmacokinetic and pharmacodynamic properties of recombinant therapeutic proteins by manipulation of sialic acid content. Biomed Pharmacother 2023; 163:114757. [PMID: 37087980 DOI: 10.1016/j.biopha.2023.114757] [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: 02/16/2023] [Revised: 04/13/2023] [Accepted: 04/20/2023] [Indexed: 04/25/2023] Open
Abstract
The circulatory half-life of recombinant therapeutic proteins is an important pharmacokinetic attribute because it determines the dosing frequency of these drugs, translating directly to treatment cost. Thus, recombinant therapeutic glycoproteins such as monoclonal antibodies have been chemically modified by various means to enhance their circulatory half-life. One approach is to manipulate the N-glycan composition of these agents. Among the many glycan constituents, sialic acid (specifically, N-acetylneuraminic acid) plays a critical role in extending circulatory half-life by masking the terminal galactose that would otherwise be recognised by the hepatic asialoglycoprotein receptor (ASGPR), resulting in clearance of the biotherapeutic from the circulation. This review aims to provide an illustrative overview of various strategies to enhance the pharmacokinetic/pharmacodynamic properties of recombinant therapeutic proteins through manipulation of their sialic acid content.
Collapse
Affiliation(s)
- Sean Chia
- Bioprocessing Technology Institute, Agency for Science, Technology and Research (A⁎STAR), 20 Biopolis Way, #06-01, Centros, 138668, Singapore
| | - Shi Jie Tay
- Bioprocessing Technology Institute, Agency for Science, Technology and Research (A⁎STAR), 20 Biopolis Way, #06-01, Centros, 138668, Singapore
| | - Zhiwei Song
- Bioprocessing Technology Institute, Agency for Science, Technology and Research (A⁎STAR), 20 Biopolis Way, #06-01, Centros, 138668, Singapore
| | - Yuansheng Yang
- Bioprocessing Technology Institute, Agency for Science, Technology and Research (A⁎STAR), 20 Biopolis Way, #06-01, Centros, 138668, Singapore
| | - Ian Walsh
- Bioprocessing Technology Institute, Agency for Science, Technology and Research (A⁎STAR), 20 Biopolis Way, #06-01, Centros, 138668, Singapore.
| | - Kuin Tian Pang
- Bioprocessing Technology Institute, Agency for Science, Technology and Research (A⁎STAR), 20 Biopolis Way, #06-01, Centros, 138668, Singapore; School of Chemistry, Chemical Engineering, and Biotechnology, Nanyang Technology University, 62 Nanyang Drive, N1.2-B3, 637459, Singapore.
| |
Collapse
|
6
|
Trastoy B, Du JJ, Cifuente JO, Rudolph L, García-Alija M, Klontz EH, Deredge D, Sultana N, Huynh CG, Flowers MW, Li C, Sastre DE, Wang LX, Corzana F, Mallagaray A, Sundberg EJ, Guerin ME. Mechanism of antibody-specific deglycosylation and immune evasion by Streptococcal IgG-specific endoglycosidases. Nat Commun 2023; 14:1705. [PMID: 36973249 PMCID: PMC10042849 DOI: 10.1038/s41467-023-37215-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2022] [Accepted: 03/03/2023] [Indexed: 03/29/2023] Open
Abstract
Bacterial pathogens have evolved intricate mechanisms to evade the human immune system, including the production of immunomodulatory enzymes. Streptococcus pyogenes serotypes secrete two multi-modular endo-β-N-acetylglucosaminidases, EndoS and EndoS2, that specifically deglycosylate the conserved N-glycan at Asn297 on IgG Fc, disabling antibody-mediated effector functions. Amongst thousands of known carbohydrate-active enzymes, EndoS and EndoS2 represent just a handful of enzymes that are specific to the protein portion of the glycoprotein substrate, not just the glycan component. Here, we present the cryoEM structure of EndoS in complex with the IgG1 Fc fragment. In combination with small-angle X-ray scattering, alanine scanning mutagenesis, hydrolytic activity measurements, enzyme kinetics, nuclear magnetic resonance and molecular dynamics analyses, we establish the mechanisms of recognition and specific deglycosylation of IgG antibodies by EndoS and EndoS2. Our results provide a rational basis from which to engineer novel enzymes with antibody and glycan selectivity for clinical and biotechnological applications.
Collapse
Affiliation(s)
- Beatriz Trastoy
- Structural Glycobiology Laboratory, Biocruces Health Research Institute, Barakaldo, Bizkaia, 48903, Spain.
- Structural Glycobiology Laboratory, Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Building 801A, 48160, Derio, Spain.
- Ikerbasque, Basque Foundation for Science, 48009, Bilbao, Spain.
| | - Jonathan J Du
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Javier O Cifuente
- Structural Glycobiology Laboratory, Biocruces Health Research Institute, Barakaldo, Bizkaia, 48903, Spain
- Structural Glycobiology Laboratory, Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Building 801A, 48160, Derio, Spain
| | - Lorena Rudolph
- University of Lübeck, Center of Structural and Cell Biology in Medicine (CSCM), Institute of Chemistry and Metabolomics, Ratzeburger Allee 160, 23562, Lübeck, Germany
| | - Mikel García-Alija
- Structural Glycobiology Laboratory, Biocruces Health Research Institute, Barakaldo, Bizkaia, 48903, Spain
- Structural Glycobiology Laboratory, Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Building 801A, 48160, Derio, Spain
| | - Erik H Klontz
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
- Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
| | - Daniel Deredge
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, MD, 21201, USA
| | - Nazneen Sultana
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Chau G Huynh
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Maria W Flowers
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Chao Li
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD, 20742, USA
| | - Diego E Sastre
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Lai-Xi Wang
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD, 20742, USA
| | - Francisco Corzana
- Departamento Química and Centro de Investigación en Síntesis Quı́mica, Universidad de La Rioja, 26006, Rioja, Spain
| | - Alvaro Mallagaray
- University of Lübeck, Center of Structural and Cell Biology in Medicine (CSCM), Institute of Chemistry and Metabolomics, Ratzeburger Allee 160, 23562, Lübeck, Germany.
| | - Eric J Sundberg
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA.
| | - Marcelo E Guerin
- Structural Glycobiology Laboratory, Biocruces Health Research Institute, Barakaldo, Bizkaia, 48903, Spain.
- Structural Glycobiology Laboratory, Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Building 801A, 48160, Derio, Spain.
- Ikerbasque, Basque Foundation for Science, 48009, Bilbao, Spain.
| |
Collapse
|
7
|
Abstract
Glycosylation has a profound influence on protein activity and cell biology through a variety of mechanisms, such as protein stability, receptor interactions and signal transduction. In many rheumatic diseases, a shift in protein glycosylation occurs, and is associated with inflammatory processes and disease progression. For example, the Fc-glycan composition on (auto)antibodies is associated with disease activity, and the presence of additional glycans in the antigen-binding domains of some autoreactive B cell receptors can affect B cell activation. In addition, changes in synovial fibroblast cell-surface glycosylation can alter the synovial microenvironment and are associated with an altered inflammatory state and disease activity in rheumatoid arthritis. The development of our understanding of the role of glycosylation of plasma proteins (particularly (auto)antibodies), cells and tissues in rheumatic pathological conditions suggests that glycosylation-based interventions could be used in the treatment of these diseases.
Collapse
Affiliation(s)
- Theresa Kissel
- Department of Rheumatology, Leiden University Medical Center, Leiden, Netherlands
| | - René E M Toes
- Department of Rheumatology, Leiden University Medical Center, Leiden, Netherlands
| | - Thomas W J Huizinga
- Department of Rheumatology, Leiden University Medical Center, Leiden, Netherlands
| | - Manfred Wuhrer
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Leiden, Netherlands.
| |
Collapse
|
8
|
Klontz EH. Chop-chop: The future of bacterial enzymes in transfusion medicine. Transfus Med Rev 2022; 36:246-251. [DOI: 10.1016/j.tmrv.2022.05.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Accepted: 05/25/2022] [Indexed: 10/15/2022]
|
9
|
Haslund-Gourley BS, Aziz PV, Heithoff DM, Restagno D, Fried JC, Ilse MB, Bäumges H, Mahan MJ, Lübke T, Marth JD. Establishment of blood glycosidase activities and their excursions in sepsis. PNAS NEXUS 2022; 1:pgac113. [PMID: 35967980 PMCID: PMC9364217 DOI: 10.1093/pnasnexus/pgac113] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 07/05/2022] [Indexed: 02/05/2023]
Abstract
Glycosidases are hydrolytic enzymes studied principally in the context of intracellular catabolism within the lysosome. Therefore, glycosidase activities are classically measured in experimentally acidified assay conditions reflecting their low pH optima. However, glycosidases are also present in the bloodstream where they may retain sufficient activity to participate in the regulation of glycoprotein half-lives, proteostasis, and disease pathogenesis. We have, herein, established at physiological pH 7.4 in blood plasma and sera the normal ranges of four major glycosidase activities essential for blood glycoprotein remodeling in healthy mice and humans. These activities included β-galactosidase, β-N-acetylglucosaminidase, α-mannosidase, and α-fucosidase. We have identified their origins to include the mammalian genes Glb1, HexB, Man2a1, and Fuca1. In experimental sepsis, excursions of glycosidase activities occurred with differences in host responses to discrete bacterial pathogens. Among similar excursions in human sepsis, the elevation of β-galactosidase activity was a prognostic indicator of increased likelihood of patient death.
Collapse
Affiliation(s)
- Benjamin S Haslund-Gourley
- Sanford-Burnham-Prebys Medical Discovery Institute, Infectious and Inflammatory Diseases Center, La Jolla, CA 92037, USA
| | - Peter V Aziz
- Sanford-Burnham-Prebys Medical Discovery Institute, Infectious and Inflammatory Diseases Center, La Jolla, CA 92037, USA
| | - Douglas M Heithoff
- Department of Molecular, Cellular, and Developmental Biology, University of California Santa Barbara, CA 93106, USA
| | - Damien Restagno
- Sanford-Burnham-Prebys Medical Discovery Institute, Infectious and Inflammatory Diseases Center, La Jolla, CA 92037, USA
| | - Jeffrey C Fried
- Department of Pulmonary and Critical Care Medicine, Cottage Hospital of Santa Barbara, Santa Barbara, CA 93105, USA
| | - Mai-Britt Ilse
- Department of Chemistry, Biochemistry, Bielefeld University, D-33615, Germany
| | - Hannah Bäumges
- Department of Chemistry, Biochemistry, Bielefeld University, D-33615, Germany
| | - Michael J Mahan
- Department of Molecular, Cellular, and Developmental Biology, University of California Santa Barbara, CA 93106, USA
| | - Torben Lübke
- Department of Chemistry, Biochemistry, Bielefeld University, D-33615, Germany
| | - Jamey D Marth
- Sanford-Burnham-Prebys Medical Discovery Institute, Infectious and Inflammatory Diseases Center, La Jolla, CA 92037, USA
| |
Collapse
|
10
|
Vattepu R, Sneed SL, Anthony RM. Sialylation as an Important Regulator of Antibody Function. Front Immunol 2022; 13:818736. [PMID: 35464485 PMCID: PMC9021442 DOI: 10.3389/fimmu.2022.818736] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 03/17/2022] [Indexed: 12/14/2022] Open
Abstract
Antibodies play a critical role in linking the adaptive immune response to the innate immune system. In humans, antibodies are categorized into five classes, IgG, IgM, IgA, IgE, and IgD, based on constant region sequence, structure, and tropism. In serum, IgG is the most abundant antibody, comprising 75% of antibodies in circulation, followed by IgA at 15%, IgM at 10%, and IgD and IgE are the least abundant. All human antibody classes are post-translationally modified by sugars. The resulting glycans take on many divergent structures and can be attached in an N-linked or O-linked manner, and are distinct by antibody class, and by position on each antibody. Many of these glycan structures on antibodies are capped by sialic acid. It is well established that the composition of the N-linked glycans on IgG exert a profound influence on its effector functions. However, recent studies have described the influence of glycans, particularly sialic acid for other antibody classes. Here, we discuss the role of glycosylation, with a focus on terminal sialylation, in the biology and function across all antibody classes. Sialylation has been shown to influence not only IgG, but IgE, IgM, and IgA biology, making it an important and unappreciated regulator of antibody function.
Collapse
Affiliation(s)
- Ravi Vattepu
- Center for Immunology and Inflammatory Diseases, Division of Rheumatology, Allergy and Immunology, Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
| | - Sunny Lyn Sneed
- Center for Immunology and Inflammatory Diseases, Division of Rheumatology, Allergy and Immunology, Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
| | - Robert M Anthony
- Center for Immunology and Inflammatory Diseases, Division of Rheumatology, Allergy and Immunology, Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
| |
Collapse
|
11
|
Insights into substrate recognition and specificity for IgG by Endoglycosidase S2. PLoS Comput Biol 2021; 17:e1009103. [PMID: 34310592 PMCID: PMC8354483 DOI: 10.1371/journal.pcbi.1009103] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 08/10/2021] [Accepted: 06/30/2021] [Indexed: 01/15/2023] Open
Abstract
Antibodies bind foreign antigens with high affinity and specificity leading to their neutralization and/or clearance by the immune system. The conserved N-glycan on IgG has significant impact on antibody effector function, with the endoglycosidases of Streptococcus pyogenes deglycosylating the IgG to evade the immune system, a process catalyzed by the endoglycosidase EndoS2. Studies have shown that two of the four domains of EndoS2, the carbohydrate binding module (CBM) and the glycoside hydrolase (GH) domain are critical for catalytic activity. To yield structural insights into contributions of the CBM and the GH domains as well as the overall flexibility of EndoS2 to the proteins’ catalytic activity, models of EndoS2-Fc complexes were generated through enhanced-sampling molecular-dynamics (MD) simulations and site-identification by ligand competitive saturation (SILCS) docking followed by reconstruction and multi-microsecond MD simulations. Modeling results predict that EndoS2 initially interacts with the IgG through its CBM followed by interactions with the GH yielding catalytically competent states. These may involve the CBM and GH of EndoS2 simultaneously interacting with either the same Fc CH2/CH3 domain or individually with the two Fc CH2/CH3 domains, with EndoS2 predicted to assume closed conformations in the former case and open conformations in the latter. Apo EndoS2 is predicted to sample both the open and closed states, suggesting that either complex can directly form following initial IgG-EndoS2 encounter. Interactions of the CBM and GH domains with the IgG are predicted to occur through both its glycan and protein regions. Simulations also predict that the Fc glycan can directly transfer from the CBM to the GH, facilitating formation of catalytically competent complexes and how the 734 to 751 loop on the CBM can facilitate extraction of the glycan away from the Fc CH2/CH3 domain. The predicted models are compared and consistent with Hydrogen/Deuterium Exchange data. In addition, the complex models are consistent with the high specificity of EndoS2 for the glycans on IgG supporting the validity of the predicted models. The pathogen Streptococcus pyogenes uses the endoglycosidases S and S2 to cleave the glycans on the Fc portion of IgG antibodies, leading to a decreased cytotoxicity of the antibodies, thereby evading the host immune response. To identify potential structures of the complex of EndoS2 with IgG that could lead to the catalytic hydrolysis of the IgG glycan, molecular modeling and molecular dynamics simulations were applied. The resulting structural models predict that EndoS2 initially interacts through its carbohydrate binding module (CBM) with the IgG with subsequent interactions with the catalytic glycoside hydrolase (GH) domain yielding stable complexes. In the modeled complexes the CBM and the GH interact either simultaneously with the same Fc CH2/CH3 domain or with the two individual Fc CH2/CH3 domains separately to yield potentially catalytically competent species. In addition, apo EndoS2 is shown to assume both open and closed conformations allowing it to directly form either type of complex from which deglycosylation of either mono- or diglycosylated IgG species may occur.
Collapse
|
12
|
Liu T, Han J, Zhang R, Tang Z, Yi G, Gong W, Wan L, Hu Q, Teng J, Liu H, Cheng X, Ye J, Su Y, Sun Y, Shi Y, Gu J, Ren S, Yang C, Shi H. Characteristics of purified Anti-β2GPI IgG N-glycosylation associate with thrombotic, obstetric, and catastrophic antiphospholipid syndrome. Rheumatology (Oxford) 2021; 61:1243-1254. [PMID: 34015111 DOI: 10.1093/rheumatology/keab416] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 05/03/2021] [Indexed: 12/20/2022] Open
Abstract
OBJECTIVE Anti-β-2 glycoprotein I (anti-β2GPI) antibodies, defined as primary pathogenic antibody in antiphospholipid syndrome (APS). It has been reported that IgG Fc N-glycosylation affects IgG effector, we aim to investigate the association of Fc glycosylation profiles of purified anti-β2GP1 IgG with clinical features of APS. METHODS We purify anti-β2GPI IgG and total IgG from 82 APS patients including 9 catastrophic antiphospholipid syndrome (CAPS) patients, as well as total IgG from 103 healthy controls to quantitatively analyze all detectable Fc N-glycanforms of all IgG subclasses with Multiple Reaction Monitoring (MRM) method based on UPLC-ESI-QqQ mass spectrometry. RESULTS Both purified anti-β2GPI IgG and APS total IgG showed altered N-glycan profiles when compared with HC IgG. Anti-β2GPI IgG presented with lower galactosylation, increased bisection and core fucosylation compared with APS total IgG and HC IgG. We found higher galactosylation of aβ2GPI IgG2 in thrombotic APS compared with the obstetric APS, and lower galactosylation of aβ2GPI IgG2 associated with late pregnancy morbidity. Moreover, low galactosylation of all anti-β2GPI IgG subclasses, increased bisection and core fucosylation of anti-β2GPI IgG1/2 were strongly associated with CAPS and triple positivity of antiphospholipid antibodies (aPLs). CONCLUSION We comprehensively characterize the N-Glycans landscape of both anti-β2GP1 and total IgG in APS. Altered N-glycan profiles of anti-β2GPI IgG enables enabled the antibodies with proinflammatory properties. Furthermore, we associated levels of IgG Fc-glycosylation with clinical features antiphospholipid syndrome. These findings could increase our understanding of anti-β2GPI antibody mediated mechanisms in APS and be used to develop diagnostics and new target treatments.
Collapse
Affiliation(s)
- Tingting Liu
- Department of Rheumatology and Immunology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No. 197 Ruijin Second Road, Shanghai, 200025, China
| | - Jing Han
- NHC Key Laboratory of Glycoconjugates Research, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China
| | - Rongrong Zhang
- NHC Key Laboratory of Glycoconjugates Research, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China
| | - Zihan Tang
- Department of Rheumatology and Immunology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No. 197 Ruijin Second Road, Shanghai, 200025, China
| | - Gang Yi
- Shanghai Institute of Immunology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Wen Gong
- Department of Rheumatology and Immunology, Yancheng First Hospital, Affiliated Hospital of Nanjing University Medical School, The First people's Hospital of Yancheng, Yancheng, 224001, China
| | - Liyan Wan
- Department of Rheumatology and Immunology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No. 197 Ruijin Second Road, Shanghai, 200025, China
| | - Qiongyi Hu
- Department of Rheumatology and Immunology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No. 197 Ruijin Second Road, Shanghai, 200025, China
| | - Jialin Teng
- Department of Rheumatology and Immunology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No. 197 Ruijin Second Road, Shanghai, 200025, China
| | - Honglei Liu
- Department of Rheumatology and Immunology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No. 197 Ruijin Second Road, Shanghai, 200025, China
| | - Xiaobing Cheng
- Department of Rheumatology and Immunology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No. 197 Ruijin Second Road, Shanghai, 200025, China
| | - Junna Ye
- Department of Rheumatology and Immunology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No. 197 Ruijin Second Road, Shanghai, 200025, China
| | - Yutong Su
- Department of Rheumatology and Immunology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No. 197 Ruijin Second Road, Shanghai, 200025, China
| | - Yue Sun
- Department of Rheumatology and Immunology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No. 197 Ruijin Second Road, Shanghai, 200025, China
| | - Yi Shi
- Bio-X institutes, Key laboratory for the Genetic of Departmental and Neuropsychiatric Disorders, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai, 20030, China
| | - Jianxin Gu
- NHC Key Laboratory of Glycoconjugates Research, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China
| | - Shifang Ren
- NHC Key Laboratory of Glycoconjugates Research, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, 200032, China
| | - Chengde Yang
- Department of Rheumatology and Immunology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No. 197 Ruijin Second Road, Shanghai, 200025, China
| | - Hui Shi
- Department of Rheumatology and Immunology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, No. 197 Ruijin Second Road, Shanghai, 200025, China
| |
Collapse
|
13
|
Spiteri VA, Doutch J, Rambo RP, Gor J, Dalby PA, Perkins SJ. Solution structure of deglycosylated human IgG1 shows the role of C H2 glycans in its conformation. Biophys J 2021; 120:1814-1834. [PMID: 33675758 DOI: 10.1016/j.bpj.2021.02.038] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 02/04/2021] [Accepted: 02/24/2021] [Indexed: 02/06/2023] Open
Abstract
The human immunoglobulin G (IgG) class is the most prevalent antibody in serum, with the IgG1 subclass being the most abundant. IgG1 is composed of two Fab regions connected to a Fc region through a 15-residue hinge peptide. Two glycan chains are conserved in the Fc region in IgG; however, their importance for the structure of intact IgG1 has remained unclear. Here, we subjected glycosylated and deglycosylated monoclonal human IgG1 (designated as A33) to a comparative multidisciplinary structural study of both forms. After deglycosylation using peptide:N-glycosidase F, analytical ultracentrifugation showed that IgG1 remained monomeric and the sedimentation coefficients s020,w of IgG1 decreased from 6.45 S by 0.16-0.27 S. This change was attributed to the reduction in mass after glycan removal. X-ray and neutron scattering revealed changes in the Guinier structural parameters after deglycosylation. Although the radius of gyration (RG) was unchanged, the cross-sectional radius of gyration (RXS-1) increased by 0.1 nm, and the commonly occurring distance peak M2 of the distance distribution curve P(r) increased by 0.4 nm. These changes revealed that the Fab-Fc separation in IgG1 was perturbed after deglycosylation. To explain these changes, atomistic scattering modeling based on Monte Carlo simulations resulted in 123,284 and 119,191 trial structures for glycosylated and deglycosylated IgG1 respectively. From these, 100 x-ray and neutron best-fit models were determined. For these, principal component analyses identified five groups of structural conformations that were different for glycosylated and deglycosylated IgG1. The Fc region in glycosylated IgG1 showed a restricted range of conformations relative to the Fab regions, whereas the Fc region in deglycosylated IgG1 showed a broader conformational spectrum. These more variable Fc conformations account for the loss of binding to the Fcγ receptor in deglycosylated IgG1.
Collapse
Affiliation(s)
- Valentina A Spiteri
- Department of Structural and Molecular Biology, Division of Biosciences, University College London, London, United Kingdom
| | - James Doutch
- ISIS Facility, STFC Rutherford Appleton Laboratory, Harwell Campus, Didcot, Oxfordshire, United Kingdom
| | - Robert P Rambo
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire, United Kingdom
| | - Jayesh Gor
- Department of Structural and Molecular Biology, Division of Biosciences, University College London, London, United Kingdom
| | - Paul A Dalby
- Department of Biochemical Engineering, University College London, London, United Kingdom
| | - Stephen J Perkins
- Department of Structural and Molecular Biology, Division of Biosciences, University College London, London, United Kingdom.
| |
Collapse
|
14
|
Sjögren J, Lood R, Nägeli A. On enzymatic remodeling of IgG glycosylation; unique tools with broad applications. Glycobiology 2020; 30:254-267. [PMID: 31616919 PMCID: PMC7109354 DOI: 10.1093/glycob/cwz085] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Revised: 09/05/2019] [Accepted: 09/30/2019] [Indexed: 01/14/2023] Open
Abstract
The importance of IgG glycosylation has been known for many years not only by scientists in glycobiology but also by human pathogens that have evolved specific enzymes to modify these glycans with fundamental impact on IgG function. The rise of IgG as a major therapeutic scaffold for many cancer and immunological indications combined with the availability of unique enzymes acting specifically on IgG Fc-glycans have spurred a range of applications to study this important post-translational modification on IgG. This review article introduces why the IgG glycans are of distinguished interest, gives a background on the unique enzymatic tools available to study the IgG glycans and finally presents an overview of applications utilizing these enzymes for various modifications of the IgG glycans. The applications covered include site-specific glycan transglycosylation and conjugation, analytical workflows for monoclonal antibodies and serum diagnostics. Additionally, the review looks ahead and discusses the importance of O-glycosylation for IgG3, Fc-fusion proteins and other new formats of biopharmaceuticals.
Collapse
Affiliation(s)
| | - Rolf Lood
- Genovis AB, Scheelevägen 2, 223 63 Lund, Sweden
| | | |
Collapse
|
15
|
Du JJ, Klontz EH, Guerin ME, Trastoy B, Sundberg EJ. Structural insights into the mechanisms and specificities of IgG-active endoglycosidases. Glycobiology 2020; 30:268-279. [PMID: 31172182 DOI: 10.1093/glycob/cwz042] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 05/22/2019] [Accepted: 06/02/2019] [Indexed: 11/12/2022] Open
Abstract
The conserved N-glycan on Asn297 of immunoglobulin G (IgG) has significant impacts on antibody effector functions, and is a frequent target for antibody engineering. Chemoenzymatic synthesis has emerged as a strategy for producing antibodies with homogenous glycosylation and improved effector functions. Central to this strategy is the use of enzymes with activity on the Asn297 glycan. EndoS and EndoS2, produced by Streptococcus pyogenes, are endoglycosidases with remarkable specificity for Asn297 glycosylation, making them ideal tools for chemoenzymatic synthesis. Although both enzymes are specific for IgG, EndoS2 recognizes a wider range of glycans than EndoS. Recent progress has been made in understanding the structural basis for their activities on antibodies. In this review, we examine the molecular mechanism of glycosidic bond cleavage by these enzymes and how specific point mutations convert them into glycosynthases. We also discuss the structural basis for differences in the glycan repertoire that IgG-active endoglycosidases recognize, which focuses on the structure of the loops within the glycoside hydrolase (GH) domain. Finally, we discuss the important contributions of carbohydrate binding modules (CBMs) to endoglycosidase activity, and how CBMs work in concert with GH domains to produce optimal activity on IgG.
Collapse
Affiliation(s)
- Jonathan J Du
- Institute of Human Virology 725 W Lombard Street, Baltimore, MD 21201, USA
| | - Erik H Klontz
- Institute of Human Virology 725 W Lombard Street, Baltimore, MD 21201, USA.,Department of Microbiology & Department of Microbiology and Immunology, University of Maryland School of Medicine, 685 West Baltimore Street HSF-I Suite 380, Baltimore, MD 21201, USA.,Program in Molecular Microbiology & Immunology, University of Maryland School of Medicine, 685 West Baltimore Street, HSF-I Suite 380, Baltimore, MD 21201, USA
| | - Marcelo E Guerin
- Structural Biology Unit, CIC bioGUNE, Bizkaia Technology Park, 48160 Derio, Spain.,IKERBASQUE, Basque Foundation for Science, María Díaz Haroko Kalea, 3, 48013 Bilbo, Bizkaia, Spain
| | - Beatriz Trastoy
- Program in Molecular Microbiology & Immunology, University of Maryland School of Medicine, 685 West Baltimore Street, HSF-I Suite 380, Baltimore, MD 21201, USA
| | - Eric J Sundberg
- Institute of Human Virology 725 W Lombard Street, Baltimore, MD 21201, USA.,Department of Microbiology & Department of Microbiology and Immunology, University of Maryland School of Medicine, 685 West Baltimore Street HSF-I Suite 380, Baltimore, MD 21201, USA.,Department of Medicine, University of Maryland School of Medicine, 655 W Baltimore St, Baltimore, MD 21201, USA
| |
Collapse
|
16
|
Ladel S, Maigler F, Flamm J, Schlossbauer P, Handl A, Hermann R, Herzog H, Hummel T, Mizaikoff B, Schindowski K. Impact of Glycosylation and Species Origin on the Uptake and Permeation of IgGs through the Nasal Airway Mucosa. Pharmaceutics 2020; 12:E1014. [PMID: 33114132 PMCID: PMC7690786 DOI: 10.3390/pharmaceutics12111014] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Revised: 10/18/2020] [Accepted: 10/21/2020] [Indexed: 12/31/2022] Open
Abstract
Although we have recently reported the involvement of neonatal Fc receptor (FcRn) in intranasal transport, the transport mechanisms are far from being elucidated. Ex vivo porcine olfactory tissue, primary cells from porcine olfactory epithelium (OEPC) and the human cell line RPMI 2650 were used to evaluate the permeation of porcine and human IgG antibodies through the nasal mucosa. IgGs were used in their wild type and deglycosylated form to investigate the impact of glycosylation. Further, the expression of FcRn and Fc-gamma receptor (FCGR) and their interaction with IgG were analyzed. Comparable permeation rates for human and porcine IgG were observed in OEPC, which display the highest expression of FcRn. Only traces of porcine IgGs could be recovered at the basolateral compartment in ex vivo olfactory tissue, while human IgGs reached far higher levels. Deglycosylated human IgG showed significantly higher permeation in comparison to the wild type in RPMI 2650 and OEPC, but insignificantly elevated in the ex vivo model. An immunoprecipitation with porcine primary cells and tissue identified FCGR2 as a potential interaction partner in the nasal mucosa. Glycosylation sensitive receptors appear to be involved in the uptake, transport, but also degradation of therapeutic IgGs in the airway epithelial layer.
Collapse
Affiliation(s)
- Simone Ladel
- Institute of Applied Biotechnology, University of Applied Science Biberach, Hubertus-Liebrecht Straße 35, 88400 Biberach, Germany; (S.L.); (F.M.); (J.F.); (P.S.); (A.H.); (R.H.); (H.H.)
- Faculty of Natural Science, University of Ulm, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Frank Maigler
- Institute of Applied Biotechnology, University of Applied Science Biberach, Hubertus-Liebrecht Straße 35, 88400 Biberach, Germany; (S.L.); (F.M.); (J.F.); (P.S.); (A.H.); (R.H.); (H.H.)
- Faculty of Natural Science, University of Ulm, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Johannes Flamm
- Institute of Applied Biotechnology, University of Applied Science Biberach, Hubertus-Liebrecht Straße 35, 88400 Biberach, Germany; (S.L.); (F.M.); (J.F.); (P.S.); (A.H.); (R.H.); (H.H.)
- Faculty of Natural Science, University of Ulm, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Patrick Schlossbauer
- Institute of Applied Biotechnology, University of Applied Science Biberach, Hubertus-Liebrecht Straße 35, 88400 Biberach, Germany; (S.L.); (F.M.); (J.F.); (P.S.); (A.H.); (R.H.); (H.H.)
| | - Alina Handl
- Institute of Applied Biotechnology, University of Applied Science Biberach, Hubertus-Liebrecht Straße 35, 88400 Biberach, Germany; (S.L.); (F.M.); (J.F.); (P.S.); (A.H.); (R.H.); (H.H.)
- Faculty of Natural Science, University of Ulm, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Rebecca Hermann
- Institute of Applied Biotechnology, University of Applied Science Biberach, Hubertus-Liebrecht Straße 35, 88400 Biberach, Germany; (S.L.); (F.M.); (J.F.); (P.S.); (A.H.); (R.H.); (H.H.)
| | - Helena Herzog
- Institute of Applied Biotechnology, University of Applied Science Biberach, Hubertus-Liebrecht Straße 35, 88400 Biberach, Germany; (S.L.); (F.M.); (J.F.); (P.S.); (A.H.); (R.H.); (H.H.)
- Faculty of Natural Science, University of Ulm, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Thomas Hummel
- Smell & Taste Clinic, Department of Otorhinolaryngology, TU Dresden, Fetscherstraße 74, 01307 Dresden, Germany;
| | - Boris Mizaikoff
- Institute of Analytical and Bioanalytical Chemistry, University of Ulm, Albert-Einstein-Allee 11, 89081 Ulm, Germany;
| | - Katharina Schindowski
- Institute of Applied Biotechnology, University of Applied Science Biberach, Hubertus-Liebrecht Straße 35, 88400 Biberach, Germany; (S.L.); (F.M.); (J.F.); (P.S.); (A.H.); (R.H.); (H.H.)
| |
Collapse
|
17
|
Temming AR, Bentlage AEH, de Taeye SW, Bosman GP, Lissenberg-Thunnissen SN, Derksen NIL, Brasser G, Mok JY, van Esch WJE, Howie HL, Zimring JC, Vidarsson G. Cross-reactivity of mouse IgG subclasses to human Fc gamma receptors: Antibody deglycosylation only eliminates IgG2b binding. Mol Immunol 2020; 127:79-86. [PMID: 32947169 DOI: 10.1016/j.molimm.2020.08.015] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 08/14/2020] [Accepted: 08/24/2020] [Indexed: 12/16/2022]
Abstract
Immunoglobulin G (IgG) antibodies are important for protection against pathogens and exert effector functions through binding to IgG-Fc receptors (FcγRs) on myeloid and natural killer cells, resulting in destruction of opsonized target cells. Despite interspecies differences, IgG subclasses and FcγRs show substantial similarities and functional conservation between mammals. Accordingly, binding of human IgG (hIgG) to mouse FcγRs (mFcγRs) has been utilized to study effector functions of hIgG in mice. In other applications, such as immunostaining with mouse IgG monoclonal antibodies (mAbs), these cross-reactivities are undesired and prone to misinterpretation. Despite this drawback, the binding of mouse IgG (mIgG) subclasses to human FcγR (hFcγR) classes has never been fully documented. Here, we report detailed and quantifiable characterization of binding affinities for all mIgG subclasses to hFcγRs, including functional polymorphic variants. mIgG subclasses show the strongest binding to hFcγRIa, with relative affinities mIgG2a = mIgG2c > mIgG3 >> mIgG2b, and no binding by mIgG1. hFcγRIIa/b showed general low reactivities to all mIgG (mIgG1> mIgG2a/c > mIgG2b), with no reactivity to mIgG3. A particularly high affinity was observed for mIgG1 to the hFcγRIIa-R131 polymorphic variant. hFcγRIIIa showed lower binding (mIgG2a/c > mIgG3), slightly favouring binding to the hFcγRIIIa-V158 over the F158 polymorphic variant. No binding was observed of mIgG to hFcγRIIIb. Deglycosylation of mIgG1 did not abrogate binding to hFcγRIIa-R131, nor did deglycosylation of mIgG2a/c and mIgG3 prevent hFcγRIa binding. Importantly, deglycosylation of the least cross-reactive mIgG subclass, mIgG2b, abrogated reactivity to all hFcγRs. Together, these data document for the first time the full spectrum of cross-reactivities of mouse IgG to human FcγRs.
Collapse
Affiliation(s)
- A Robin Temming
- Department of Experimental Immunohematology, Sanquin Research and Landsteiner Laboratory, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Arthur E H Bentlage
- Department of Experimental Immunohematology, Sanquin Research and Landsteiner Laboratory, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Steven W de Taeye
- Department of Experimental Immunohematology, Sanquin Research and Landsteiner Laboratory, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, The Netherlands; Department of Immunopathology, Sanquin Research and Landsteiner Laboratory, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Gerlof P Bosman
- Department of Chemical Biology and Drug Discovery, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands
| | - Suzanne N Lissenberg-Thunnissen
- Department of Experimental Immunohematology, Sanquin Research and Landsteiner Laboratory, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Ninotska I L Derksen
- Department of Immunopathology, Sanquin Research and Landsteiner Laboratory, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | | | - Juk Yee Mok
- Sanquin Reagents, Amsterdam, The Netherlands
| | | | - Heather L Howie
- Department of Pathology, Carter Immunology Center, University of Virginia School of Medicine, Charlottesville, Virginia, United States
| | - James C Zimring
- Department of Pathology, Carter Immunology Center, University of Virginia School of Medicine, Charlottesville, Virginia, United States
| | - Gestur Vidarsson
- Department of Experimental Immunohematology, Sanquin Research and Landsteiner Laboratory, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
| |
Collapse
|
18
|
Donald LJ, Spearman M, Mishra N, Komatsu E, Butler M, Perreault H. Mass spectrometric analysis of core fucosylation and sequence variation in a human-camelid monoclonal antibody. Mol Omics 2020; 16:221-230. [PMID: 32163054 DOI: 10.1039/c9mo00168a] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Electrospray mass spectrometry (ESI-MS) was used to measure the masses of an intact dimeric monoclonal antibody (Mab) and assess the fucosylation level. The Mab under study was EG2-hFc, a chimeric human-camelid antibody of about 80 kDa (A. Bell et al., Cancer Lett., 2010, 289(1), 81-90). It was obtained from cell culture with and without a fucosylation inhibitor, and treated with EndoS which cleaves between the two core N-acetyl glucosamine (GlcNAc) residues. It is the first time that this combined approach with a unique mass spectrometer was used to measure 146 Da differences as part of a large intact dimeric antibody. Results showed that in the dimer, both heavy chains were fucosylated on the core GlcNAc of the Fc Asn site equivalent to Asn297. In the presence of the fucosylation inhibitor, fucosylation was lost on both subunits. Following reduction, monomers were analyzed and the masses obtained corroborated the dimer results. Dimeric EG2-hFc Mab treated with PNGase F, to deglycosylate the protein, was also measured by MS for mass comparison. In spite of the success of fucosylation level measurements, the experimental masses of deglycosylated dimers and GlcNAc-Fuc bearing dimers did not correspond to masses of our sequence of reference (A. Bell et al., Cancer Lett., 2010, 289(1), 81-90; ; ), which prompted experiments to determine the protein backbone sequence. Digest mixtures from trypsin, GluC, as well as trypsin + GluC proteolysis were analyzed by matrix-assisted laser desorption/ionization (MALDI) MS and MS/MS. A few variations were found relative to the reference sequence, which are discussed in detail herein. These measurements allowed us to build a new "experimental" sequence for the EG2-hFc samples investigated in this work, although there are still ambiguities to be resolved in this new sequence. MALDI-MS/MS also confirmed the fucosylation pattern in the Fc tryptic peptide EEQYNSTYR.
Collapse
Affiliation(s)
- Lynda J Donald
- Department of Microbiology, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
| | | | | | | | | | | |
Collapse
|
19
|
Unique Microbial Catabolic Pathway for the Human Core N-Glycan Constituent Fucosyl-α-1,6- N-Acetylglucosamine-Asparagine. mBio 2020; 11:mBio.02804-19. [PMID: 31937642 PMCID: PMC6960285 DOI: 10.1128/mbio.02804-19] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
The gastrointestinal tract accommodates more than 1014 microorganisms that have an enormous impact on human health. The mechanisms enabling commensal bacteria and administered probiotics to colonize the gut remain largely unknown. The ability to utilize host-derived carbon and energy resources available at the mucosal surfaces may provide these bacteria with a competitive advantage in the gut. Here, we have identified in the commensal species Lactobacillus casei a novel metabolic pathway for the utilization of the glycoamino acid fucosyl-α-1,6-N-GlcNAc-Asn, which is present in the core-fucosylated N-glycoproteins from mammalians. These results give insight into the molecular interactions between the host and commensal/probiotic bacteria and may help to devise new strategies to restore gut microbiota homeostasis in diseases associated with dysbiotic microbiota. The survival of commensal bacteria in the human gut partially depends on their ability to metabolize host-derived molecules. The use of the glycosidic moiety of N-glycoproteins by bacteria has been reported, but the role of N-glycopeptides or glycoamino acids as the substrates for bacterial growth has not been evaluated. We have identified in Lactobacillus casei strain BL23 a gene cluster (alf-2) involved in the catabolism of the glycoamino acid fucosyl-α-1,6-N-GlcNAc-Asn (6′FN-Asn), a constituent of the core-fucosylated structures of mammalian N-glycoproteins. The cluster consists of the genes alfHC, encoding a major facilitator superfamily (MFS) permease and the α-l-fucosidase AlfC, and the divergently oriented asdA (aspartate 4-decarboxylase), alfR2 (transcriptional regulator), pepV (peptidase), asnA2 (glycosyl-asparaginase), and sugK (sugar kinase) genes. Knockout mutants showed that alfH, alfC, asdA, asnA2, and sugK are necessary for efficient 6′FN-Asn utilization. The alf-2 genes are induced by 6′FN-Asn, but not by its glycan moiety, via the AlfR2 regulator. The constitutive expression of alf-2 genes in an alfR2 strain allowed the metabolism of a variety of 6′-fucosyl-glycans. However, GlcNAc-Asn did not support growth in this mutant background, indicating that the presence of a 6′-fucose moiety is crucial for substrate transport via AlfH. Within bacteria, 6′FN-Asn is defucosylated by AlfC, generating GlcNAc-Asn. This glycoamino acid is processed by the glycosylasparaginase AsnA2. GlcNAc-Asn hydrolysis generates aspartate and GlcNAc, which is used as a fermentable source by L.casei. These data establish the existence in a commensal bacterial species of an exclusive metabolic pathway likely to scavenge human milk and mucosal fucosylated N-glycopeptides in the gastrointestinal tract.
Collapse
|
20
|
Schaffert A, Hanić M, Novokmet M, Zaytseva O, Krištić J, Lux A, Nitschke L, Peipp M, Pezer M, Hennig R, Rapp E, Lauc G, Nimmerjahn F. Minimal B Cell Extrinsic IgG Glycan Modifications of Pro- and Anti-Inflammatory IgG Preparations in vivo. Front Immunol 2020; 10:3024. [PMID: 31998308 PMCID: PMC6970187 DOI: 10.3389/fimmu.2019.03024] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Accepted: 12/10/2019] [Indexed: 01/02/2023] Open
Abstract
Select residues in the biantennary sugar moiety attached to the fragment crystallizable of immunoglobulin G (IgG) antibodies can modulate IgG effector functions. Thus, afucosylated IgG glycovariants have enhanced cytotoxic activity, whereas IgG glycovariants rich in terminal sialic acid residues can trigger anti-inflammatory effects. More recent evidence suggests that terminal α2,6 linked sialic acids can be attached to antibodies post IgG secretion. These findings raise concerns for the use of therapeutic antibodies as they may change their glycosylation status in the patient and hence affect their activity. To investigate to what extent B cell extrinsic sialylation processes modify therapeutic IgG preparations in vivo, we analyzed changes in human intravenous IgG (IVIg) sialylation upon injection in mice deficient in B cells or in mice lacking the sialyltransferase 1, which catalyzes the addition of α2,6 linked sialic acid residues. By performing a time course of IgG glycan analysis with HILIC-UPLC-FLR (plus MS) and xCGE-LIF our study suggests that therapeutic IgG glycosylation is stable upon injection in vivo. Only a very small fraction of IgG molecules acquired sialic acid structures predominantly in the Fab- but not the Fc-portion upon injection in vivo, suggesting that therapeutic antibody glycosylation will remain stable upon injection in vivo.
Collapse
Affiliation(s)
- Anja Schaffert
- Department of Biology, Institute of Genetics, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Maja Hanić
- Glycoscience Research Laboratory, Genos Ltd., Zagreb, Croatia
| | - Mislav Novokmet
- Glycoscience Research Laboratory, Genos Ltd., Zagreb, Croatia
| | - Olga Zaytseva
- Glycoscience Research Laboratory, Genos Ltd., Zagreb, Croatia
| | | | - Anja Lux
- Department of Biology, Institute of Genetics, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Lars Nitschke
- Department of Biology, Institute of Genetics, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Matthias Peipp
- Department of Medicine II, Christian-Albrechts University Kiel and University Medical Center Schleswig-Holstein, Kiel, Germany
| | - Marija Pezer
- Glycoscience Research Laboratory, Genos Ltd., Zagreb, Croatia
| | - René Hennig
- glyXera GmbH, Magdeburg, Germany.,Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Germany
| | - Erdmann Rapp
- glyXera GmbH, Magdeburg, Germany.,Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Germany
| | - Gordan Lauc
- Glycoscience Research Laboratory, Genos Ltd., Zagreb, Croatia.,Faculty of Pharmacy and Biochemistry, University of Zagreb, Zagreb, Croatia
| | - Falk Nimmerjahn
- Department of Biology, Institute of Genetics, University of Erlangen-Nuremberg, Erlangen, Germany
| |
Collapse
|
21
|
Mishra N, Spearman M, Donald L, Perreault H, Butler M. Comparison of two glycoengineering strategies to control the fucosylation of a monoclonal antibody. J Biotechnol 2020; 324S:100015. [DOI: 10.1016/j.btecx.2020.100015] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 01/16/2020] [Accepted: 02/14/2020] [Indexed: 12/21/2022]
|
22
|
Segelmark M, Björck L. Streptococcal Enzymes as Precision Tools Against Pathogenic IgG Autoantibodies in Small Vessel Vasculitis. Front Immunol 2019; 10:2165. [PMID: 31616410 PMCID: PMC6763725 DOI: 10.3389/fimmu.2019.02165] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Accepted: 08/28/2019] [Indexed: 11/24/2022] Open
Abstract
In primary systemic small vessel vasculitis autoantibodies are common and seem to play an important role in the pathogenesis. Autoantibodies in vasculitis are preferentially directed against components of the immune system or directly against components of the vessel wall. Plasmapheresis is often applied in emergency situationists when the function of vital organs is jeopardized, the level of clinical evidence to apply such therapy, however, varies between low and non-existing. Plasmapheresis is a blunt and unspecific instrument that requires several sessions to achieve a substantial reduction of autoantibody levels. IdeS and EndoS are two relatively recently discovered enzymes produced by S. pyogenes, that have a remarkable capacity to degrade and disarm IgG. They have shown positive results in several in vivo models of autoimmunity, and treatment with IdeS has successfully been used to inactivate HLA alloantibodies in patients undergoing renal transplantation. Both IdeS and EndoS have the potential to become precision tools to replace plasmapheresis in the treatment of vasculitic emergencies and a clinical trial of IdeS in anti-GBM vasculitis is now ongoing.
Collapse
Affiliation(s)
- Mårten Segelmark
- Nephrology, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Lars Björck
- Infection Medicine, Department of Clinical Sciences, Lund University, Lund, Sweden
| |
Collapse
|
23
|
Henderson SR, Salama AD. Diagnostic and management challenges in Goodpasture's (anti-glomerular basement membrane) disease. Nephrol Dial Transplant 2019; 33:196-202. [PMID: 28459999 DOI: 10.1093/ndt/gfx057] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Accepted: 03/09/2017] [Indexed: 12/19/2022] Open
Abstract
Goodpasture's or anti-glomerular basement membrane (GBM) disease is classically characterized by the presence of circulating autoantibodies directed against the non-collagenous domain of the α3 chain of type IV collagen, targeting glomerular and alveolar basement membranes, and associated with rapidly progressive crescentic glomerulonephritis, with alveolar haemorrhage in over half the patients. However, there are increasing examples of variants or atypical presentations of this disease, and novel therapeutic options have been proposed, which nephrologists should be aware of. The pathophysiology of this condition has been understood through molecular analysis of the antibody-antigen interactions and the use of human leucocyte antigen-transgenic animals, while the association of anti-GBM antibodies with anti-neutrophil cytoplasm antibodies and their combined impact on disease phenotype is increasingly recognized, providing some insights into the basis of glomerular damage and autoimmunity.
Collapse
Affiliation(s)
- Scott R Henderson
- Centre for Nephrology, Division of Medicine, University College London, Royal Free Hospital, London, UK
| | - Alan D Salama
- Centre for Nephrology, Division of Medicine, University College London, Royal Free Hospital, London, UK
| |
Collapse
|
24
|
Steffen U, Schett G, Bozec A. How Autoantibodies Regulate Osteoclast Induced Bone Loss in Rheumatoid Arthritis. Front Immunol 2019; 10:1483. [PMID: 31333647 PMCID: PMC6619397 DOI: 10.3389/fimmu.2019.01483] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Accepted: 06/13/2019] [Indexed: 12/29/2022] Open
Abstract
Rheumatoid arthritis (RA) is a chronic inflammatory disease, characterized by autoimmunity that triggers joint inflammation and tissue destruction. Traditional concepts of RA pathogenesis have strongly been focused on inflammation. However, more recent evidence suggests that autoimmunity per se modulates the disease and in particular bone destruction during the course of RA. RA-associated bone loss is caused by increased osteoclast differentiation and activity leading to rapid bone resorption. Autoimmunity in RA is based on autoantibodies such as rheumatoid factor (RF) and autoantibodies against citrullinated proteins (ACPA). These autoantibodies exert effector functions on immune cells and on bone resorbing osteoclasts, thereby facilitating bone loss. This review summarizes potential pathways involved in increased destruction of bone tissue in RA, particularly focusing on the direct and indirect actions of autoantibodies on osteoclast generation and function.
Collapse
Affiliation(s)
- Ulrike Steffen
- Department of Internal Medicine 3, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Georg Schett
- Department of Internal Medicine 3, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Aline Bozec
- Department of Internal Medicine 3, University of Erlangen-Nuremberg, Erlangen, Germany
| |
Collapse
|
25
|
Naegeli A, Bratanis E, Karlsson C, Shannon O, Kalluru R, Linder A, Malmström J, Collin M. Streptococcus pyogenes evades adaptive immunity through specific IgG glycan hydrolysis. J Exp Med 2019; 216:1615-1629. [PMID: 31092533 PMCID: PMC6605743 DOI: 10.1084/jem.20190293] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Revised: 04/15/2019] [Accepted: 04/16/2019] [Indexed: 12/19/2022] Open
Abstract
EndoS from Streptococcus pyogenes hydrolyzes the functionally important glycan on the Fc portion of IgG during infections in humans. In mice with IgG mediated immunity against the M1 protein on the bacteria, EndoS is a virulence factor. Streptococcus pyogenes (Group A streptococcus; GAS) is a human pathogen causing diseases from uncomplicated tonsillitis to life-threatening invasive infections. GAS secretes EndoS, an endoglycosidase that specifically cleaves the conserved N-glycan on IgG antibodies. In vitro, removal of this glycan impairs IgG effector functions, but its relevance to GAS infection in vivo is unclear. Using targeted mass spectrometry, we characterized the effects of EndoS on host IgG glycosylation during the course of infections in humans. Substantial IgG glycan hydrolysis occurred at the site of infection and systemically in the severe cases. We demonstrated decreased resistance to phagocytic killing of GAS lacking EndoS in vitro and decreased virulence in a mouse model of invasive infection. This is the first described example of specific bacterial IgG glycan hydrolysis during infection and thereby verifies the hypothesis that EndoS modifies antibodies in vivo. This mechanisms of immune evasion could have implications for treatment of severe GAS infections and for future efforts at vaccine development.
Collapse
Affiliation(s)
- Andreas Naegeli
- Faculty of Medicine, Department of Clinical Sciences, Division of Infection Medicine, Lund University, Lund, Sweden
| | - Eleni Bratanis
- Faculty of Medicine, Department of Clinical Sciences, Division of Infection Medicine, Lund University, Lund, Sweden
| | - Christofer Karlsson
- Faculty of Medicine, Department of Clinical Sciences, Division of Infection Medicine, Lund University, Lund, Sweden
| | - Oonagh Shannon
- Faculty of Medicine, Department of Clinical Sciences, Division of Infection Medicine, Lund University, Lund, Sweden
| | - Raja Kalluru
- Faculty of Medicine, Department of Clinical Sciences, Division of Infection Medicine, Lund University, Lund, Sweden
| | - Adam Linder
- Faculty of Medicine, Department of Clinical Sciences, Division of Infection Medicine, Lund University, Lund, Sweden
| | - Johan Malmström
- Faculty of Medicine, Department of Clinical Sciences, Division of Infection Medicine, Lund University, Lund, Sweden
| | - Mattias Collin
- Faculty of Medicine, Department of Clinical Sciences, Division of Infection Medicine, Lund University, Lund, Sweden
| |
Collapse
|
26
|
Klontz EH, Trastoy B, Deredge D, Fields JK, Li C, Orwenyo J, Marina A, Beadenkopf R, Günther S, Flores J, Wintrode PL, Wang LX, Guerin ME, Sundberg EJ. Molecular Basis of Broad Spectrum N-Glycan Specificity and Processing of Therapeutic IgG Monoclonal Antibodies by Endoglycosidase S2. ACS CENTRAL SCIENCE 2019; 5:524-538. [PMID: 30937380 PMCID: PMC6439443 DOI: 10.1021/acscentsci.8b00917] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Indexed: 06/02/2023]
Abstract
Immunoglobulin G (IgG) glycosylation critically modulates antibody effector functions. Streptococcus pyogenes secretes a unique endo-β-N-acetylglucosaminidase, EndoS2, which deglycosylates the conserved N-linked glycan at Asn297 on IgG Fc to eliminate its effector functions and evade the immune system. EndoS2 and specific point mutants have been used to chemoenzymatically synthesize antibodies with customizable glycosylation for gain of functions. EndoS2 is useful in these schemes because it accommodates a broad range of N-glycans, including high-mannose, complex, and hybrid types; however, its mechanism of substrate recognition is poorly understood. We present crystal structures of EndoS2 alone and bound to complex and high-mannose glycans; the broad N-glycan specificity is governed by critical loops that shape the binding site of EndoS2. Furthermore, hydrolytic experiments, domain-swap chimeras, and hydrogen-deuterium exchange mass spectrometry reveal the importance of the carbohydrate-binding module in the mechanism of IgG recognition by EndoS2, providing insights into engineering enzymes to catalyze customizable glycosylation reactions.
Collapse
Affiliation(s)
- Erik H. Klontz
- Institute
of Human Virology, Department of Microbiology & Immunology, and Program in Molecular
Microbiology & Immunology, University
of Maryland School of Medicine, Baltimore, Maryland 21201, United States
| | - Beatriz Trastoy
- Structural
Biology Unit, CIC bioGUNE, Bizkaia Technology Park, 48160 Derio, Spain
| | - Daniel Deredge
- Department
of Pharmaceutical Sciences, University of
Maryland School of Pharmacy, Baltimore, Maryland 21201, United States
| | - James K. Fields
- Institute
of Human Virology, Department of Microbiology & Immunology, and Program in Molecular
Microbiology & Immunology, University
of Maryland School of Medicine, Baltimore, Maryland 21201, United States
| | - Chao Li
- Department
of Chemistry and Biochemistry, University
of Maryland, College Park, Maryland 20742, United States
| | - Jared Orwenyo
- Department
of Chemistry and Biochemistry, University
of Maryland, College Park, Maryland 20742, United States
| | - Alberto Marina
- Structural
Biology Unit, CIC bioGUNE, Bizkaia Technology Park, 48160 Derio, Spain
| | - Robert Beadenkopf
- Institute
of Human Virology, Department of Microbiology & Immunology, and Program in Molecular
Microbiology & Immunology, University
of Maryland School of Medicine, Baltimore, Maryland 21201, United States
| | - Sebastian Günther
- Institute
of Human Virology, Department of Microbiology & Immunology, and Program in Molecular
Microbiology & Immunology, University
of Maryland School of Medicine, Baltimore, Maryland 21201, United States
- Photon
Science, Deutsches Elektronen-Synchrotron, Hamburg 22607, Germany
| | - Jair Flores
- Institute
of Human Virology, Department of Microbiology & Immunology, and Program in Molecular
Microbiology & Immunology, University
of Maryland School of Medicine, Baltimore, Maryland 21201, United States
| | - Patrick L. Wintrode
- Department
of Pharmaceutical Sciences, University of
Maryland School of Pharmacy, Baltimore, Maryland 21201, United States
| | - Lai-Xi Wang
- Department
of Chemistry and Biochemistry, University
of Maryland, College Park, Maryland 20742, United States
| | - Marcelo E. Guerin
- Structural
Biology Unit, CIC bioGUNE, Bizkaia Technology Park, 48160 Derio, Spain
- IKERBASQUE,
Basque Foundation for Science, 48013 Bilbao, Spain
| | - Eric J. Sundberg
- Institute
of Human Virology, Department of Microbiology & Immunology, and Program in Molecular
Microbiology & Immunology, University
of Maryland School of Medicine, Baltimore, Maryland 21201, United States
- Department
of Medicine, University of Maryland School
of Medicine, Baltimore, Maryland 21201, United States
| |
Collapse
|
27
|
Abstract
Autoimmunity is a leading cause of chronic kidney disease and loss of native and transplanted kidneys. Conventional immunosuppressive therapies can be effective but are non-specific, noncurative, and risk serious side effects such as life-threatening infection and cancer. Novel therapies and targeted interventions are urgently needed. In this brief review we explore diverse strategies currently in development and under consideration to interrupt underlying disease mechanisms in immune-mediated renal injury. Because autoantibodies are prominent in diagnosis and pathogenesis in multiple human glomerulopathies, we highlight several promising therapies that interfere with functions of early mediators (IgG and complement) of the effector arm and with an epicenter (the germinal center) for induction of humoral immunity.
Collapse
Affiliation(s)
- Mary Helen Foster
- a Department of Medicine , Duke University Medical Center , Durham , NC , USA.,b Medical and Research Services , Durham VA Medical Center , Durham , NC , USA
| | | |
Collapse
|
28
|
Nandakumar KS, Collin M, Happonen KE, Lundström SL, Croxford AM, Xu B, Zubarev RA, Rowley MJ, Blom AM, Kjellman C, Holmdahl R. Streptococcal Endo-β- N-Acetylglucosaminidase Suppresses Antibody-Mediated Inflammation In Vivo. Front Immunol 2018; 9:1623. [PMID: 30061892 PMCID: PMC6054937 DOI: 10.3389/fimmu.2018.01623] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 07/02/2018] [Indexed: 12/19/2022] Open
Abstract
Endo-β-N-acetylglucosaminidase (EndoS) is a family 18 glycosyl hydrolase secreted by Streptococcus pyogenes. Recombinant EndoS hydrolyzes the β-1,4-di-N-acetylchitobiose core of the N-linked complex type glycan on the asparagine 297 of the γ-chains of IgG. Here, we report that EndoS and IgG hydrolyzed by EndoS induced suppression of local immune complex (IC)-mediated arthritis. A small amount (1 µg given i.v. to a mouse) of EndoS was sufficient to inhibit IgG-mediated arthritis in mice. The presence of EndoS disturbed larger IC lattice formation both in vitro and in vivo, as visualized with anti-C3b staining. Neither complement binding in vitro nor antigen-antibody binding per se were affected. Thus, EndoS could potentially be used for treating patients with IC-mediated pathology.
Collapse
Affiliation(s)
- Kutty Selva Nandakumar
- School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, China.,Medical Inflammation Research, Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden
| | - Mattias Collin
- Division of Infection Medicine, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Kaisa E Happonen
- Department of Translational Medicine, Lund University, Lund, Sweden.,Molecular Neurobiology Laboratory, Salk Institute for Biological Studies, La Jolla, CA, United States
| | - Susanna L Lundström
- Division of Physiological Chemistry I, Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden
| | - Allyson M Croxford
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, Australia
| | - Bingze Xu
- Medical Inflammation Research, Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden
| | - Roman A Zubarev
- Division of Physiological Chemistry I, Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden
| | - Merrill J Rowley
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, Australia
| | - Anna M Blom
- Department of Translational Medicine, Lund University, Lund, Sweden
| | | | - Rikard Holmdahl
- School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, China.,Medical Inflammation Research, Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden
| |
Collapse
|
29
|
Karsten CM, Beckmann T, Holtsche MM, Tillmann J, Tofern S, Schulze FS, Heppe EN, Ludwig RJ, Zillikens D, König IR, Köhl J, Schmidt E. Tissue Destruction in Bullous Pemphigoid Can Be Complement Independent and May Be Mitigated by C5aR2. Front Immunol 2018; 9:488. [PMID: 29599777 PMCID: PMC5862877 DOI: 10.3389/fimmu.2018.00488] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 02/23/2018] [Indexed: 12/12/2022] Open
Abstract
Bullous pemphigoid (BP), the most frequent autoimmune bullous disorder, is a paradigmatic autoantibody-mediated disease associated with autoantibodies against BP180 (type XVII collagen, Col17). Several animal models have been developed that reflect important clinical and immunological features of human BP. Complement activation has been described as a prerequisite for blister formation, however, the recent finding that skin lesions can be induced by anti-Col17 F(ab')2 fragments indicates complement-independent mechanisms to contribute to blister formation in BP. Here, C5-/- mice injected with anti-Col17 IgG showed a reduction of skin lesions by about 50% associated with significantly less skin-infiltrating neutrophils compared to wild-type mice. Reduction of skin lesions and neutrophil infiltration was seen independently of the employed anti-Col17 IgG dose. Further, C5ar1-/- mice were protected from disease development, whereas the extent of skin lesions was increased in C5ar2-/- animals. Pharmacological inhibition of C5a receptor 1 (C5aR1) by PMX53 led to reduced disease activity when applied in a prophylactic setting. In contrast, PMX-53 treatment had no effect when first skin lesions had already developed. While C5aR1 was critically involved in neutrophil migration in vitro, its role for Col17-anti-Col17 IgG immune complex-mediated release of reactive oxygen species from neutrophils was less pronounced. Our data demonstrate that complement-dependent and -independent mechanisms coexist in anti-Col17-autoantibody-mediated tissue destruction. C5aR1 and C5aR2 seem to play opposing roles in this process with C5aR1 exerting its primary effect in recruiting inflammatory cells to the skin during the early phase of the disease. Further studies are required to fully understand the role of C5aR2 in autoantibody-mediated skin inflammation.
Collapse
MESH Headings
- Animals
- Autoantibodies/genetics
- Autoantibodies/immunology
- Autoantigens/genetics
- Autoantigens/immunology
- Complement C5/genetics
- Complement C5/immunology
- Mice
- Mice, Inbred BALB C
- Mice, Knockout
- Neutrophil Infiltration
- Neutrophils/immunology
- Neutrophils/pathology
- Non-Fibrillar Collagens/genetics
- Non-Fibrillar Collagens/immunology
- Pemphigoid, Bullous/chemically induced
- Pemphigoid, Bullous/genetics
- Pemphigoid, Bullous/immunology
- Pemphigoid, Bullous/pathology
- Peptides, Cyclic/pharmacology
- Reactive Oxygen Species/immunology
- Receptor, Anaphylatoxin C5a/antagonists & inhibitors
- Receptor, Anaphylatoxin C5a/genetics
- Receptor, Anaphylatoxin C5a/immunology
- Skin/immunology
- Skin/pathology
- Collagen Type XVII
Collapse
Affiliation(s)
| | - Tina Beckmann
- Lübeck Institute of Experimental Dermatology (LIED), University of Lübeck, Lübeck, Germany
| | | | - Jenny Tillmann
- Institute of Systemic Inflammation, University of Lübeck, Lübeck, Germany
| | - Sabrina Tofern
- Lübeck Institute of Experimental Dermatology (LIED), University of Lübeck, Lübeck, Germany
| | - Franziska S. Schulze
- Lübeck Institute of Experimental Dermatology (LIED), University of Lübeck, Lübeck, Germany
| | - Eva Nina Heppe
- Lübeck Institute of Experimental Dermatology (LIED), University of Lübeck, Lübeck, Germany
| | - Ralf J. Ludwig
- Lübeck Institute of Experimental Dermatology (LIED), University of Lübeck, Lübeck, Germany
| | - Detlef Zillikens
- Department of Dermatology, University of Lübeck, Lübeck, Germany
| | - Inke R. König
- Institute of Medical Biometry and Statistics, University of Lübeck, Lübeck, Germany
| | - Jörg Köhl
- Institute of Systemic Inflammation, University of Lübeck, Lübeck, Germany
- Division of Immunobiology, Cincinnati Children’s Hospital and College of Medicine, University of Cincinnati, Cincinnati, OH, United States
| | - Enno Schmidt
- Lübeck Institute of Experimental Dermatology (LIED), University of Lübeck, Lübeck, Germany
- Department of Dermatology, University of Lübeck, Lübeck, Germany
| |
Collapse
|
30
|
Nandakumar KS. Targeting IgG in Arthritis: Disease Pathways and Therapeutic Avenues. Int J Mol Sci 2018; 19:E677. [PMID: 29495570 PMCID: PMC5877538 DOI: 10.3390/ijms19030677] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Revised: 01/25/2018] [Accepted: 02/22/2018] [Indexed: 12/11/2022] Open
Abstract
Rheumatoid arthritis (RA) is a polygenic and multifactorial syndrome. Many complex immunological and genetic interactions are involved in the final outcome of the clinical disease. Autoantibodies (rheumatoid factors, anti-citrullinated peptide/protein antibodies) are present in RA patients' sera for a long time before the onset of clinical disease. Prior to arthritis onset, in the autoantibody response, epitope spreading, avidity maturation, and changes towards a pro-inflammatory Fc glycosylation phenotype occurs. Genetic association of epitope specific autoantibody responses and the induction of inflammation dependent and independent changes in the cartilage by pathogenic autoantibodies emphasize the crucial contribution of antibody-initiated inflammation in RA development. Targeting IgG by glyco-engineering, bacterial enzymes to specifically cleave IgG/alter N-linked Fc-glycans at Asn 297 or blocking the downstream effector pathways offers new avenues to develop novel therapeutics for arthritis treatment.
Collapse
Affiliation(s)
- Kutty Selva Nandakumar
- School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510000, China.
- Department of Medical Biochemistry and Biophysics, Karolinska Institute, 17177 Stockholm, Sweden.
| |
Collapse
|
31
|
Characterization of novel endo-β-N-acetylglucosaminidases from Sphingobacterium species, Beauveria bassiana and Cordyceps militaris that specifically hydrolyze fucose-containing oligosaccharides and human IgG. Sci Rep 2018; 8:246. [PMID: 29321565 PMCID: PMC5762919 DOI: 10.1038/s41598-017-17467-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Accepted: 11/27/2017] [Indexed: 02/06/2023] Open
Abstract
Endo-β-N-acetylglucosaminidase (ENGase) catalyzes hydrolysis of N-linked oligosaccharides. Although many ENGases have been characterized from various organisms, so far no fucose-containing oligosaccharides-specific ENGase has been identified in any organism. Here, we screened soil samples, using dansyl chloride (Dns)-labeled sialylglycan (Dns-SG) as a substrate, and discovered a strain that exhibits ENGase activity in the culture supernatant; this strain, named here as strain HMA12, was identified as a Sphingobacterium species by 16S ribosomal RNA gene analysis. By draft genome sequencing, five candidate ENGase encoding genes were identified in the genome of this strain. Among them, a recombinant protein purified from Escherichia coli expressing the candidate gene ORF1188 exhibited fucose-containing oligosaccharides-specific ENGase activity. The ENGase exhibited optimum activities at very acidic pHs (between pH 2.3–2.5). A BLAST search using the sequence of ORF1188 identified two fungal homologs, one in Beauveria bassiana and the other in Cordyceps militaris. Recombinant ORF1188, Beauveria and Cordyceps ENGases released the fucose-containing oligosaccharides residues from rituximab (immunoglobulin G) but not the high-mannose-containing oligosaccharides residues from RNase B, a result that not only confirmed the substrate specificity of these novel ENGases but also suggested that natural glycoproteins could be their substrates.
Collapse
|
32
|
Mimura Y, Katoh T, Saldova R, O'Flaherty R, Izumi T, Mimura-Kimura Y, Utsunomiya T, Mizukami Y, Yamamoto K, Matsumoto T, Rudd PM. Glycosylation engineering of therapeutic IgG antibodies: challenges for the safety, functionality and efficacy. Protein Cell 2018; 9:47-62. [PMID: 28597152 PMCID: PMC5777974 DOI: 10.1007/s13238-017-0433-3] [Citation(s) in RCA: 140] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Accepted: 05/22/2017] [Indexed: 12/25/2022] Open
Abstract
Glycosylation of the Fc region of IgG has a profound impact on the safety and clinical efficacy of therapeutic antibodies. While the biantennary complex-type oligosaccharide attached to Asn297 of the Fc is essential for antibody effector functions, fucose and outer-arm sugars attached to the core heptasaccharide that generate structural heterogeneity (glycoforms) exhibit unique biological activities. Hence, efficient and quantitative glycan analysis techniques have been increasingly important for the development and quality control of therapeutic antibodies, and glycan profiles of the Fc are recognized as critical quality attributes. In the past decade our understanding of the influence of glycosylation on the structure/function of IgG-Fc has grown rapidly through X-ray crystallographic and nuclear magnetic resonance studies, which provides possibilities for the design of novel antibody therapeutics. Furthermore, the chemoenzymatic glycoengineering approach using endoglycosidase-based glycosynthases may facilitate the development of homogeneous IgG glycoforms with desirable functionality as next-generation therapeutic antibodies. Thus, the Fc glycans are fertile ground for the improvement of the safety, functionality, and efficacy of therapeutic IgG antibodies in the era of precision medicine.
Collapse
Affiliation(s)
- Yusuke Mimura
- Department of Clinical Research, NHO Yamaguchi-Ube Medical Center, 685 Higashi-Kiwa, Ube, 755-0241, Japan.
| | - Toshihiko Katoh
- Laboratory of Molecular Biology and Bioresponse, Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University, Kitashirakawa, Oiwake-Cho, Sakyo-Ku, Kyoto, 606-8502, Japan
| | - Radka Saldova
- NIBRT GlycoScience Group, National Institute for Bioprocessing Research and Training, Mount Merrion, Blackrock, Dublin 4, Ireland
| | - Roisin O'Flaherty
- NIBRT GlycoScience Group, National Institute for Bioprocessing Research and Training, Mount Merrion, Blackrock, Dublin 4, Ireland
| | - Tomonori Izumi
- Center for Regenerative Medicine, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami Kogushi, Ube, 755-8505, Japan
| | - Yuka Mimura-Kimura
- Department of Clinical Research, NHO Yamaguchi-Ube Medical Center, 685 Higashi-Kiwa, Ube, 755-0241, Japan
| | - Toshiaki Utsunomiya
- Department of Clinical Research, NHO Yamaguchi-Ube Medical Center, 685 Higashi-Kiwa, Ube, 755-0241, Japan
| | - Yoichi Mizukami
- Center for Gene Research, Yamaguchi University, 1-1-1 Minami-Kogushi, Ube, 755-8505, Japan
| | - Kenji Yamamoto
- Research Institute for Bioresources and Biotechnology, Ishikawa Prefectural University, 1-308 Suematsu, Nonoichi, Ishikawa, 921-8836, Japan
| | - Tsuneo Matsumoto
- Department of Clinical Research, NHO Yamaguchi-Ube Medical Center, 685 Higashi-Kiwa, Ube, 755-0241, Japan
| | - Pauline M Rudd
- NIBRT GlycoScience Group, National Institute for Bioprocessing Research and Training, Mount Merrion, Blackrock, Dublin 4, Ireland
| |
Collapse
|
33
|
Bakchoul T, Walek K, Krautwurst A, Rummel M, Bein G, Santoso S, Sachs UJ. Glycosylation of autoantibodies: Insights into the mechanisms of immune thrombocytopenia. Thromb Haemost 2017; 110:1259-66. [DOI: 10.1160/th13-04-0294] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Accepted: 08/19/2013] [Indexed: 02/01/2023]
Abstract
SummaryImmune thrombocytopenia (ITP) is a bleeding disorder caused by IgG autoantibodies (AAbs) directed against platelets (PLTs). IgG effector functions depend on their Fc-constant region which undergoes post-translational glycosylation. We investigated the role of Asn279-linked N-glycan of AAbs in vitro and in vivo. AAbs were purified from ITP patients (n=15) and N-glycans were enzymatically cleaved by endoglycosidase F. The effects of native AAbs and deglycosylated AAbs were compared in vitro on enhancement of phagocytosis of platelets by monocytes and complement fixation and activation applying flow cytometry, laser scanning microscopy, and a complement consumption assay. AAb-induced platelet phagocytosis was inhibited by N-glycan cleavage (median phagocytic activity: 8% vs 0.8%, p=0.004). Seven out of 15 native AAbs bound C1q and activated complement. N-glycan cleavage significantly reduced both effects. In vivo survival of human PLTs was assessed after co-transfusion with native or N-glycan cleaved AAbs in a NOD/SCID mouse model. Injection of AAbs resulted in rapid clearance of human platelets compared to control (platelet clearance after 5h (CL5h) 75% vs 30%, p<0.001). AAbs that were able to activate complement induced more pronounced platelet clearance in the presence of complement compared to the clearance in the absence of complement (CL5h 82% vs 62%, p=0.003). AAbs lost their ability to destroy platelets in vivo after deglycosylation (CL5h 42%, p<0.001). N-glycosylation of human ITP AAbs appears to be required for platelet phagocytosis and complement activation, reducing platelet survival in vivo. Posttranslational modification of AAbs may constitute an important determinant for the clinical manifestation of ITP.
Collapse
|
34
|
Chen CL, Hsu JC, Lin CW, Wang CH, Tsai MH, Wu CY, Wong CH, Ma C. Crystal Structure of a Homogeneous IgG-Fc Glycoform with the N-Glycan Designed to Maximize the Antibody Dependent Cellular Cytotoxicity. ACS Chem Biol 2017; 12:1335-1345. [PMID: 28318221 DOI: 10.1021/acschembio.7b00140] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
N-glycosylation on IgG modulates Fc conformation and effector functions. An IgG-Fc contains a human sialo-complex type (hSCT) glycan of biantennary structure with two α2,6-sialylations and without core-fucosylation is an optimized glycoform developed to enhance the antibody dependent cellular cytotoxicity (ADCC). hSCT modification not only enhances the binding affinity to Fc receptors in the presence of antigen but also in some cases provides gain-of-function effector activity. We used enzymatic glyco-engineering to prepare an IgG-Fc with homogeneous hSCT attached to each CH2 domain and solved its crystal structure. A compact form and an open form were observed in an asymmetric unit in the crystal. In the compact structure, the double glycan latches from the two hSCT chains stabilize the CH2 domains in a closed conformation. In the open structure, the terminal sialic acid (N-acetylneuraminic acid or NeuNAc) residue interacts through water-mediated hydrogen bonds with the D249-L251 helix, to modulate the pivot region of the CH2-CH3 interface. The double glycan latches and the sialic acid modulation may be mutually exclusive. This is the first crystal structure of glyco-engineered Fc with enhanced effector activities. This work provides insights into the relationship between the structural stability and effector functions affected by hSCT modification and the development of better antibodies for therapeutic applications.
Collapse
Affiliation(s)
- Chia-Lin Chen
- Genomics
Research Center, Academia Sinica, Taipei, Taiwan
- Chemical
Biology and Molecular Biophysics program, Taiwan International Graduate
Program, Academia Sinica, Taipei, Taiwan
- Institute
of Biochemical Sciences, National Taiwan University, Taipei, Taiwan
| | - Jen-Chi Hsu
- Genomics
Research Center, Academia Sinica, Taipei, Taiwan
| | - Chin-Wei Lin
- Genomics
Research Center, Academia Sinica, Taipei, Taiwan
- Chemical
Biology and Molecular Biophysics program, Taiwan International Graduate
Program, Academia Sinica, Taipei, Taiwan
- Department
of Chemistry, National Taiwan University, Taipei, Taiwan
| | | | | | - Chung-Yi Wu
- Genomics
Research Center, Academia Sinica, Taipei, Taiwan
- Chemical
Biology and Molecular Biophysics program, Taiwan International Graduate
Program, Academia Sinica, Taipei, Taiwan
| | - Chi-Huey Wong
- Genomics
Research Center, Academia Sinica, Taipei, Taiwan
- Chemical
Biology and Molecular Biophysics program, Taiwan International Graduate
Program, Academia Sinica, Taipei, Taiwan
- Institute
of Biochemical Sciences, National Taiwan University, Taipei, Taiwan
- Department
of Chemistry, National Taiwan University, Taipei, Taiwan
| | - Che Ma
- Genomics
Research Center, Academia Sinica, Taipei, Taiwan
- Chemical
Biology and Molecular Biophysics program, Taiwan International Graduate
Program, Academia Sinica, Taipei, Taiwan
| |
Collapse
|
35
|
Quast I, Peschke B, Lünemann JD. Regulation of antibody effector functions through IgG Fc N-glycosylation. Cell Mol Life Sci 2017; 74:837-847. [PMID: 27639381 PMCID: PMC11107549 DOI: 10.1007/s00018-016-2366-z] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Revised: 09/05/2016] [Accepted: 09/13/2016] [Indexed: 02/03/2023]
Abstract
Immunoglobulin gamma (IgG) antibodies are key effector proteins of the immune system. They recognize antigens with high specificity and are indispensable for immunological memory following pathogen exposure or vaccination. The constant, crystallizable fragment (Fc) of IgG molecules mediates antibody effector functions such as complement-dependent cytotoxicity, antibody-mediated cellular cytotoxicity, and antibody-dependent cell-mediated phagocytosis. These functions are regulated by a single N-linked, biantennary glycan of the heavy chain, which resides just below the hinge region, and the presence of specific sugar moieties on the glycan has profound implications on IgG effector functions. Emerging knowledge of how Fc glycans contribute to IgG structure and functions has opened new avenues for the therapeutic exploitation of defined antibody glycoforms in the treatment of cancer and autoimmune diseases. Here, we review recent advances in understanding proinflammatory IgG effector functions and their regulation by Fc glycans.
Collapse
Affiliation(s)
- Isaak Quast
- Laboratory of Neuroinflammation, Department of Neuroinflammation, Institute of Experimental Immunology, University of Zürich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
| | - Benjamin Peschke
- Laboratory of Neuroinflammation, Department of Neuroinflammation, Institute of Experimental Immunology, University of Zürich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
| | - Jan D Lünemann
- Laboratory of Neuroinflammation, Department of Neuroinflammation, Institute of Experimental Immunology, University of Zürich, Winterthurerstrasse 190, 8057, Zurich, Switzerland.
| |
Collapse
|
36
|
BspK, a Serine Protease from the Predatory Bacterium Bdellovibrio bacteriovorus with Utility for Analysis of Therapeutic Antibodies. Appl Environ Microbiol 2017; 83:AEM.03037-16. [PMID: 27940543 PMCID: PMC5288813 DOI: 10.1128/aem.03037-16] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 12/04/2016] [Indexed: 01/21/2023] Open
Abstract
The development of therapeutic and diagnostic antibodies is a rapidly growing field of research, being the fastest expanding group of products on the pharmaceutical market, and appropriate quality controls are crucial for their application. We have identified and characterized the serine protease termed BspK (Bdellovibrio serine protease K) from Bdellovibrio bacteriovorus and here show its activity on antibodies. Mutation of the serine residue at position 230 rendered the protease inactive. Further investigations of BspK enzymatic characteristics revealed autoproteolytic activity, resulting in numerous cleavage products. Two of the autoproteolytic cleavage sites in the BspK fusion protein were investigated in more detail and corresponded to cleavage after K28 and K210 in the N- and C-terminal parts of BspK, respectively. Further, BspK displayed stable enzymatic activity on IgG within the pH range of 6.0 to 9.5 and was inhibited in the presence of ZnCl2. BspK demonstrated preferential hydrolysis of human IgG1 compared to other immunoglobulins and isotypes, with hydrolysis of the heavy chain at position K226 generating two separate Fab fragments and an intact IgG Fc domain. Finally, we show that BspK preferentially cleaves its substrates C-terminally to lysines similar to the protease LysC. However, BspK displays a unique cleavage profile compared to several currently used proteases on the market. IMPORTANCE The rapid development of novel therapeutic antibodies is partly hindered by difficulties in assessing their quality and safety. The lack of tools and methods facilitating such quality controls obstructs and delays the process of product approval, eventually affecting the patients in need of treatment. These difficulties in product evaluations indicate a need for new and comprehensive tools for such analysis. Additionally, recent concerns raised regarding the limitations of established products on the market (e.g., trypsin) further highlight a general need for a larger array of proteases with novel cleavage profiles to meet current and future needs, within both the life science industry and the academic research community.
Collapse
|
37
|
Collin M, Björck L. Toward Clinical use of the IgG Specific Enzymes IdeS and EndoS against Antibody-Mediated Diseases. Methods Mol Biol 2017; 1535:339-351. [PMID: 27914091 DOI: 10.1007/978-1-4939-6673-8_23] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The endoglycosidase EndoS and the protease IdeS from the human pathogen Streptococcus pyogenes are immunomodulating enzymes hydrolyzing human IgG. IdeS cleaves IgG in the lower hinge region, while EndoS hydrolyzes the conserved N-linked glycan in the Fc region. Both enzymes are remarkably specific for human IgG that after hydrolysis loses most of its effector functions, such as binding to leukocytes and complement activation, all contributing to bacterial evasion of adaptive immunity. However, taken out of their infectious context, we and others have shown that IdeS and EndoS can alleviate autoimmune disease in a number of animal models of antibody-mediated disorders. In this chapter, we will briefly describe the discovery and characterization of these unique enzymes, present the findings from a number of animal models of autoimmunity where the enzymes have been tested, and outline the ongoing clinical testing of IdeS. Furthermore, we will discuss the rationale for further development of IdeS and EndoS into novel pharmaceuticals against diseases where IgG antibodies contribute to the pathology, including, but not restricted to, chronic and acute autoimmunity, transplant rejection, and antidrug antibody reactions.
Collapse
Affiliation(s)
- Mattias Collin
- Division of Infection Medicine, Department of Clinical Sciences, Lund University, Biomedical Center B14, SE-221 84, Lund, Sweden.
| | - Lars Björck
- Division of Infection Medicine, Department of Clinical Sciences, Lund University, Biomedical Center B14, SE-221 84, Lund, Sweden
| |
Collapse
|
38
|
Mihai S, Albert H, Ludwig RJ, Iwata H, Björck L, Collin M, Nimmerjahn F. In vivo enzymatic modulation of IgG antibodies prevents immune complex-dependent skin injury. Exp Dermatol 2016; 26:691-696. [DOI: 10.1111/exd.13163] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/02/2016] [Indexed: 12/13/2022]
Affiliation(s)
- Sidonia Mihai
- Department of Biology; Institute of Genetics; University of Erlangen-Nuremberg; Erlangen Germany
- Department of Clinical Chemistry; University Hospital Erlangen; Erlangen Germany
| | - Heike Albert
- Department of Biology; Institute of Genetics; University of Erlangen-Nuremberg; Erlangen Germany
| | - Ralf J. Ludwig
- Department of Dermatology; University of Lübeck; Lübeck Germany
| | - Hiroaki Iwata
- Department of Dermatology; University of Lübeck; Lübeck Germany
| | - Lars Björck
- Division of Infection Medicine; Department of Clinical Sciences; Lund University; Lund Sweden
| | - Mattias Collin
- Division of Infection Medicine; Department of Clinical Sciences; Lund University; Lund Sweden
| | - Falk Nimmerjahn
- Department of Biology; Institute of Genetics; University of Erlangen-Nuremberg; Erlangen Germany
| |
Collapse
|
39
|
Shadnezhad A, Naegeli A, Collin M. CP40 from Corynebacterium pseudotuberculosis is an endo-β-N-acetylglucosaminidase. BMC Microbiol 2016; 16:261. [PMID: 27821068 PMCID: PMC5100271 DOI: 10.1186/s12866-016-0884-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Accepted: 10/29/2016] [Indexed: 12/21/2022] Open
Abstract
Background C. pseudotuberculosis is an important animal pathogen that causes substantial economical loss in sheep and goat farming. Zoonotic infections in humans are rare, but when they occur they are often severe and difficult to treat. One of the most studied proteins from this bacterium, the secreted protein CP40 is being developed as a promising vaccine candidate and has been characterized as a serine protease. In this study we have investigated if CP40 is an endoglycosidase rather than a protease. Results CP40 does not show any protease activity and contains an EndoS-like family 18 of glycoside hydrolase (chitinase) motif. It hydrolyzes biantennary glycans on both human and ovine IgGs. CP40 is not a general chitinase and cannot hydrolyze bisecting GlcNAc. Conclusion Taken together we present solid evidence for re-annotating CP40 as an EndoS-like endoglycosidase. Redefining the activity of this enzyme will facilitate subsequent studies that could give further insight into immune evasion mechanisms underlying corynebacterial infections in animals and humans.
Collapse
Affiliation(s)
- Azadeh Shadnezhad
- Department of Clinical Sciences, Division of Infection Medicine, Lund University, Biomedical Center B14, SE-22184, Lund, Sweden.
| | - Andreas Naegeli
- Department of Clinical Sciences, Division of Infection Medicine, Lund University, Biomedical Center B14, SE-22184, Lund, Sweden
| | - Mattias Collin
- Department of Clinical Sciences, Division of Infection Medicine, Lund University, Biomedical Center B14, SE-22184, Lund, Sweden
| |
Collapse
|
40
|
Le NPL, Bowden TA, Struwe WB, Crispin M. Immune recruitment or suppression by glycan engineering of endogenous and therapeutic antibodies. BIOCHIMICA ET BIOPHYSICA ACTA 2016; 1860:1655-68. [PMID: 27105835 PMCID: PMC4922387 DOI: 10.1016/j.bbagen.2016.04.016] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Revised: 04/15/2016] [Accepted: 04/16/2016] [Indexed: 12/20/2022]
Abstract
Human serum IgG contains multiple glycoforms which exhibit a range of binding properties to effector molecules such as cellular Fc receptors. Emerging knowledge of how the Fc glycans contribute to the antibody structure and effector functions has opened new avenues for the exploitation of defined antibody glycoforms in the treatment of diseases. Here, we review the structure and activity of antibody glycoforms and highlight developments in antibody glycoengineering by both the manipulation of the cellular glycosylation machinery and by chemoenzymatic synthesis. We discuss wide ranging applications of antibody glycoengineering in the treatment of cancer, autoimmunity and inflammation. This article is part of a Special Issue entitled "Glycans in personalised medicine" Guest Editor: Professor Gordan Lauc.
Collapse
Affiliation(s)
- Ngoc Phuong Lan Le
- Oxford Glycobiology Institute, Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, United Kingdom
| | - Thomas A Bowden
- Division of Structural Biology, University of Oxford, Wellcome Trust Centre for Human Genetics, Roosevelt Drive, Oxford OX3 7BN, United Kingdom
| | - Weston B Struwe
- Oxford Glycobiology Institute, Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, United Kingdom
| | - Max Crispin
- Oxford Glycobiology Institute, Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, United Kingdom.
| |
Collapse
|
41
|
Shadnezhad A, Naegeli A, Sjögren J, Adamczyk B, Leo F, Allhorn M, Karlsson NG, Jensen A, Collin M. EndoSd: an IgG glycan hydrolyzing enzyme in Streptococcus dysgalactiae subspecies dysgalactiae. Future Microbiol 2016; 11:721-36. [DOI: 10.2217/fmb.16.14] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Aim: The aim of this study was to identify and characterize EndoS-like enzymes in Streptococcus dysgalactiae subspecies dysgalactiae (SDSD). Materials & methods: PCR, DNA sequencing, recombinant protein expression, lectin blot, ultra high performance liquid chromatography analysis and a chitinase assay were used to identify ndoS-like genes and characterize EndoSd. Results: EndoSd were found in four SDSD strains. EndoSd hydrolyzes the chitobiose core of the glycan on IgG. The amino acid sequence of EndoSd is 70% identical to EndoS in S. pyogenes, but it has a unique C-terminal sequence. EndoSd secretion is influenced by the carbohydrate composition of the growth medium. Conclusion: Our findings indicate that IgG glycan hydrolyzing activity is present in SDSD, and that the activity can be attributed to the here identified enzyme EndoSd.
Collapse
Affiliation(s)
- Azadeh Shadnezhad
- Department of Clinical Sciences, Division of Infection Medicine, Lund University, Biomedical Center B14, SE-22184 Lund, Sweden
| | - Andreas Naegeli
- Department of Clinical Sciences, Division of Infection Medicine, Lund University, Biomedical Center B14, SE-22184 Lund, Sweden
| | - Jonathan Sjögren
- Department of Clinical Sciences, Division of Infection Medicine, Lund University, Biomedical Center B14, SE-22184 Lund, Sweden
- Genovis AB, Scheelevägen 2, SE-220 07 Lund, Sweden
| | - Barbara Adamczyk
- Department of Medical Biochemistry and Cell Biology, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Fredrik Leo
- Department of Clinical Sciences, Division of Infection Medicine, Lund University, Biomedical Center B14, SE-22184 Lund, Sweden
| | - Maria Allhorn
- Department of Clinical Sciences, Division of Infection Medicine, Lund University, Biomedical Center B14, SE-22184 Lund, Sweden
| | - Niclas G Karlsson
- Department of Medical Biochemistry and Cell Biology, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Anders Jensen
- Department of Biomedicine, Faculty of Health Sciences, Aarhus University, Aarhus, Denmark
| | - Mattias Collin
- Department of Clinical Sciences, Division of Infection Medicine, Lund University, Biomedical Center B14, SE-22184 Lund, Sweden
| |
Collapse
|
42
|
Witte M, Koga H, Hashimoto T, Ludwig RJ, Bieber K. Discovering potential drug-targets for personalized treatment of autoimmune disorders - what we learn from epidermolysis bullosa acquisita. Expert Opin Ther Targets 2016; 20:985-98. [DOI: 10.1517/14728222.2016.1148686] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Mareike Witte
- Lübeck Institute of Experimental Dermatology (LIED), University of Lübeck, Lübeck, Germany
| | - Hiroshi Koga
- Lübeck Institute of Experimental Dermatology (LIED), University of Lübeck, Lübeck, Germany
| | - Takashi Hashimoto
- Institute of Cutaneous Cell Biology, Kurume University, Kurume, Japan
| | - Ralf J. Ludwig
- Lübeck Institute of Experimental Dermatology (LIED), University of Lübeck, Lübeck, Germany
| | - Katja Bieber
- Lübeck Institute of Experimental Dermatology (LIED), University of Lübeck, Lübeck, Germany
| |
Collapse
|
43
|
A Monosaccharide Residue Is Sufficient to Maintain Mouse and Human IgG Subclass Activity and Directs IgG Effector Functions to Cellular Fc Receptors. Cell Rep 2015; 13:2376-2385. [PMID: 26670049 DOI: 10.1016/j.celrep.2015.11.027] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Revised: 10/07/2015] [Accepted: 11/06/2015] [Indexed: 11/23/2022] Open
Abstract
Immunoglobulin G (IgG) glycosylation modulates antibody activity and represents a major source of heterogeneity within antibody preparations. Depending on their glycosylation pattern, individual IgG glycovariants present in recombinant antibody preparations may trigger effects ranging from enhanced pro-inflammatory activity to increased anti-inflammatory activity. In contrast, reduction of IgG glycosylation beyond the central mannose core is generally believed to result in impaired IgG activity. However, this study reveals that a mono- or disaccharide structure consisting of one N-acetylglucosamine with or without a branching fucose residue is sufficient to retain the activity of the most active human and mouse IgG subclasses in vivo and further directs antibody activity to cellular Fcγ receptors. Notably, the activity of minimally glycosylated antibodies is not predicted by in vitro assays based on a monomeric antibody-Fcγ-receptor interaction analysis, whereas in vitro assay systems using immune complexes are more suitable to predict IgG activity in vivo.
Collapse
|
44
|
Ludwig R. Immune mechanism-targeted treatment of experimental epidermolysis bullosa acquisita. Expert Rev Clin Immunol 2015; 11:1365-78. [PMID: 26471717 DOI: 10.1586/1744666x.2015.1085801] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Epidermolysis bullosa acquisita (EBA) is an autoimmune bullous dermatosis characterized by chronic mucocutaneous blistering caused by autoantibodies directed against type VII collagen. EBA causes a high morbidity and is difficult to treat. Model systems have significantly broadened our understanding of EBA pathogenesis, leading to the identification of numerous therapeutic targets. Of these, so far, a few have been evaluated for their therapeutic potential in preclinical models. In mice, EBA can be induced by transfer of anti-type VII collagen antibodies or by immunization with the protein. The latter model, immunization-induced EBA, is ideal to test drugs for their therapeutic efficacy. Here, mice with already established disease can be treated for prolonged periods. Albeit time consuming, results from immunization-induced EBA will pave the way for clinical application in patients. As the key pathogenic principle, that is, autoantibody-induced, leukocyte-mediated tissue injury and inflammation, is shared by other diseases, these findings may have translational applications beyond EBA.
Collapse
Affiliation(s)
- Ralf Ludwig
- a University of Luebeck, Luebeck Institute of Experimental Dermatology, Ratzeburger Allee 160, Luebeck, Germany
| |
Collapse
|
45
|
Sjögren J, Cosgrave EFJ, Allhorn M, Nordgren M, Björk S, Olsson F, Fredriksson S, Collin M. EndoS and EndoS2 hydrolyze Fc-glycans on therapeutic antibodies with different glycoform selectivity and can be used for rapid quantification of high-mannose glycans. Glycobiology 2015; 25:1053-63. [PMID: 26156869 PMCID: PMC4551147 DOI: 10.1093/glycob/cwv047] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 07/03/2015] [Indexed: 12/16/2022] Open
Abstract
Enzymes that affect glycoproteins of the human immune system, and thereby modulate defense responses, are abundant among bacterial pathogens. Two endoglycosidases from the human pathogen Streptococcus pyogenes, EndoS and EndoS2, have recently been shown to hydrolyze N-linked glycans of human immunoglobulin G. However, detailed characterization and comparison of the hydrolyzing activities have not been performed. In the present study, we set out to characterize the enzymes by comparing the activities of EndoS and EndoS2 on a selection of therapeutic monoclonal antibodies (mAbs), cetuximab, adalimumab, panitumumab and denosumab. By analyzing the glycans hydrolyzed by EndoS and EndoS2 from the antibodies using matrix-assisted laser desorption ionization time of flight, we found that both the enzymes cleaved complex glycans and that EndoS2 hydrolyzed hybrid and oligomannose structures to a greater extent compared with EndoS. A comparison of ultra-high-performance liquid chromatography (LC) profiles of the glycan pool of cetuximab hydrolyzed with EndoS and EndoS2 showed that EndoS2 hydrolyzed hybrid and oligomannose glycans, whereas these peaks were missing in the EndoS chromatogram. We utilized this difference in glycoform selectivity, in combination with the IdeS protease, and developed a LC separation method to quantify high mannose content in the Fc fragments of the selected mAbs. We conclude that EndoS and EndoS2 hydrolyze different glycoforms from the Fc-glycosylation site on therapeutic mAbs and that this can be used for rapid quantification of high mannose content.
Collapse
Affiliation(s)
- Jonathan Sjögren
- Division of Infection Medicine, Department of Clinical Sciences, Lund University, Lund 221 84, Sweden Genovis AB, Lund 200 07, Sweden
| | | | - Maria Allhorn
- Division of Infection Medicine, Department of Clinical Sciences, Lund University, Lund 221 84, Sweden
| | | | | | | | | | - Mattias Collin
- Division of Infection Medicine, Department of Clinical Sciences, Lund University, Lund 221 84, Sweden
| |
Collapse
|
46
|
Piraino MS, Kelliher MT, Aburas J, Southern CA. Single molecule Förster resonance energy transfer studies of the effect of EndoS deglycosylation on the structure of IgG. Immunol Lett 2015; 167:29-33. [PMID: 26112419 DOI: 10.1016/j.imlet.2015.06.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Revised: 06/05/2015] [Accepted: 06/15/2015] [Indexed: 12/17/2022]
Abstract
The bacterial enzyme EndoS specifically cleaves glycans bound to immunoglobulin G (IgG) molecules. Because this deglycosylation procedure leads to a diminished immune response, this enzyme has potential applications as a therapeutic for autoimmune disorders. Although the diminished immune response is attributed to a structural change in the Fc region of IgG antibodies, the specific nature of this structural change is not known due to the variety of results obtained by different experimental approaches. In order to better understand how EndoS deglycosylation impacts the structure of the Fc region of IgG antibodies, we have conducted single molecule Förster resonance energy transfer (FRET) studies of dye-labeled, freely diffusing antibodies. A comparison of the FRET efficiency histograms obtained for glycosylated and EndoS deglycosylated antibodies indicates that the Fc region can take on a wider variety of structures upon deglycosylation. This is demonstrated by the presence of additional peaks in the FRET efficiency histogram for the deglycosylated case.
Collapse
Affiliation(s)
- Mark S Piraino
- DePaul University, Department of Chemistry, 1110 West Belden Avenue, Chicago, IL 60614, United States
| | - Michael T Kelliher
- DePaul University, Department of Chemistry, 1110 West Belden Avenue, Chicago, IL 60614, United States
| | - Jihad Aburas
- DePaul University, Department of Chemistry, 1110 West Belden Avenue, Chicago, IL 60614, United States
| | - Cathrine A Southern
- DePaul University, Department of Chemistry, 1110 West Belden Avenue, Chicago, IL 60614, United States.
| |
Collapse
|
47
|
Brown EP, Normandin E, Osei-Owusu NY, Mahan AE, Chan YN, Lai JI, Vaccari M, Rao M, Franchini G, Alter G, Ackerman ME. Microscale purification of antigen-specific antibodies. J Immunol Methods 2015; 425:27-36. [PMID: 26078040 DOI: 10.1016/j.jim.2015.06.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Revised: 06/05/2015] [Accepted: 06/08/2015] [Indexed: 10/23/2022]
Abstract
Glycosylation of the Fc domain is an important driver of antibody effector function. While assessment of antibody glycoform compositions observed across total plasma IgG has identified differences associated with a variety of clinical conditions, in many cases it is the glycosylation state of only antibodies against a specific antigen or set of antigens that may be of interest, for example, in defining the potential effector function of antibodies produced during disease or after vaccination. Historically, glycoprofiling such antigen-specific antibodies in clinical samples has been challenging due to their low prevalence, the high sample requirement for most methods of glycan determination, and the lack of high-throughput purification methods. New methods of glycoprofiling with lower sample requirements and higher throughput have motivated the development of microscale and automatable methods for purification of antigen-specific antibodies from polyclonal sources such as clinical serum samples. In this work, we present a robot-compatible 96-well plate-based method for purification of antigen-specific antibodies, suitable for such population level glycosylation screening. We demonstrate the utility of this method across multiple antibody sources, using both purified plasma IgG and plasma, and across multiple different antigen types, with enrichment factors greater than 1000-fold observed. Using an on-column IdeS protease treatment, we further describe staged release of Fc and Fab domains, allowing for glycoprofiling of each domain.
Collapse
Affiliation(s)
- Eric P Brown
- Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, United States
| | - Erica Normandin
- Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, United States
| | - Nana Yaw Osei-Owusu
- Molecular and Cellular Biology Program, Dartmouth College, Hanover, NH 03755, United States
| | - Alison E Mahan
- Ragon Institute of MGH, MIT, and Harvard University, Cambridge, MA 02139, United States
| | - Ying N Chan
- Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, United States
| | - Jennifer I Lai
- Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, United States
| | - Monica Vaccari
- Animal Models and Vaccine Section, National Cancer Institute, Bethesda, MD 20814, United States
| | - Mangala Rao
- U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD 20910, United States
| | - Genoveffa Franchini
- Animal Models and Vaccine Section, National Cancer Institute, Bethesda, MD 20814, United States
| | - Galit Alter
- Ragon Institute of MGH, MIT, and Harvard University, Cambridge, MA 02139, United States
| | - Margaret E Ackerman
- Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, United States.
| |
Collapse
|
48
|
Valenzuela NM, Trinh KR, Mulder A, Morrison SL, Reed EF. Monocyte recruitment by HLA IgG-activated endothelium: the relationship between IgG subclass and FcγRIIa polymorphisms. Am J Transplant 2015; 15:1502-18. [PMID: 25648976 PMCID: PMC4439339 DOI: 10.1111/ajt.13174] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2014] [Revised: 12/01/2014] [Accepted: 12/15/2014] [Indexed: 01/25/2023]
Abstract
It is currently unclear which donor specific HLA antibodies confer the highest risk of antibody-mediated rejection (AMR) and allograft loss. In this study, we hypothesized that two distinct features (HLA IgG subclass and Fcγ receptor [FcγR] polymorphisms) which vary from patient to patient, influence the process of monocyte trafficking to and macrophage accumulation in the allograft during AMR in an interrelated fashion. Here, we investigated the contribution of human IgG subclass and FcγR polymorphisms in monocyte recruitment in vitro by primary human aortic endothelium activated with chimeric anti-HLA I human IgG1 and IgG2. Both subclasses triggered monocyte adhesion to endothelial cells, via a two-step process. First, HLA I crosslinking by antibodies stimulated upregulation of P-selectin on endothelium irrespective of IgG subclass. P-selectin-induced monocyte adhesion was enhanced by secondary interactions of IgG with FcγRs, which was highly dependent upon subclass. IgG1 was more potent than IgG2 through differential engagement of FcγRs. Monocytes homozygous for FcγRIIa-H131 adhered more readily to HLA antibody-activated endothelium compared with FcγRIIa-R131 homozygous. Finally, direct modification of HLA I antibodies with immunomodulatory enzymes EndoS and IdeS dampened recruitment by eliminating antibody-FcγR binding, an approach that may have clinical utility in reducing AMR and other forms of antibody-induced inflammation.
Collapse
Affiliation(s)
- Nicole M. Valenzuela
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA
| | - K. Ryan Trinh
- Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles, CA
| | - Arend Mulder
- Department of Immunohaematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands
| | - Sherie L. Morrison
- Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles, CA
| | - Elaine F. Reed
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA
| |
Collapse
|
49
|
Bochner BS, Zimmermann N. Role of siglecs and related glycan-binding proteins in immune responses and immunoregulation. J Allergy Clin Immunol 2015; 135:598-608. [PMID: 25592986 DOI: 10.1016/j.jaci.2014.11.031] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Revised: 11/14/2014] [Accepted: 11/25/2014] [Indexed: 12/16/2022]
Abstract
Virtually all cells and extracellular material are heavily decorated by various glycans, yet our understanding of the structure and function of these moieties lags behind the understanding of nucleic acids, lipids, and proteins. Recent years have seen a tremendous acceleration of knowledge in the field of glycobiology, revealing many intricacies and functional contributions that were previously poorly appreciated or even unrecognized. This review highlights several topics relevant to glycoimmunology in which mammalian and pathogen-derived glycans displayed on glycoproteins and other scaffolds are recognized by specific glycan-binding proteins (GBPs), leading to a variety of proinflammatory and anti-inflammatory cellular responses. The focus for this review is mainly on 2 families of GBPs, sialic acid-binding immunoglobulin-like lectins (siglecs) and selectins, that are involved in multiple steps of the immune response, including distinguishing pathogens from self, cell trafficking to sites of inflammation, fine-tuning of immune responses leading to activation or tolerance, and regulation of cell survival. Importantly for the clinician, accelerated rates of discovery in the field of glycoimmunology are being translated into innovative medical approaches that harness the interaction of glycans and GBPs to the benefit of the host and might soon lead to novel diagnostics and therapeutics.
Collapse
Affiliation(s)
- Bruce S Bochner
- Department of Medicine, Division of Allergy-Immunology, Northwestern University Feinberg School of Medicine, Chicago, Ill.
| | - Nives Zimmermann
- Department of Pediatrics, Division of Allergy and Immunology, Children's Hospital Medical Center, and Department of Pathology, University of Cincinnati College of Medicine, Cincinnati, Ohio
| |
Collapse
|
50
|
Moorthy BS, Xie B, Moussa EM, Iyer LK, Chandrasekhar S, Panchal JP, Topp EM. Effect of Hydrolytic Degradation on the In Vivo Properties of Monoclonal Antibodies. BIOBETTERS 2015. [DOI: 10.1007/978-1-4939-2543-8_8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|