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Baksmeier C, Blundell P, Steckel J, Schultz V, Gu Q, Da Silva Filipe A, Kohl A, Linnington C, Lu D, Dell A, Haslam S, Wang J, Czajkowsky D, Goebels N, Pleass RJ. Modified recombinant human IgG1-Fc is superior to natural intravenous immunoglobulin at inhibiting immune-mediated demyelination. Immunology 2021; 164:90-105. [PMID: 33880776 PMCID: PMC8358725 DOI: 10.1111/imm.13341] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 03/23/2021] [Accepted: 03/31/2021] [Indexed: 12/13/2022] Open
Abstract
Intravenous immunoglobulin (IVIG) is an established treatment for numerous autoimmune conditions. Although Fc fragments derived from IVIG have shown efficacy in controlling immune thrombocytopenia in children, the mechanisms of action are unclear and controversial. The aim of this study was to dissect IVIG effector mechanisms using further adapted Fc fragments on demyelination in an ex vivo model of the central nervous system-immune interface. Using organotypic cerebellar slice cultures (OSCs) from transgenic mice, we induced extensive immune-mediated demyelination and oligodendrocyte loss with an antibody specific for myelin oligodendrocyte glycoprotein (MOG) and complement. Protective effects of adapted Fc fragments were assessed by live imaging of green fluorescent protein expression, immunohistochemistry and confocal microscopy. Cysteine- and glycan-adapted Fc fragments protected OSC from demyelination in a dose-dependent manner where equimolar concentrations of either IVIG or control Fc were ineffective. The protective effects of the adapted Fc fragments are partly attributed to interference with complement-mediated oligodendroglia damage. Transcriptome analysis ruled out signatures associated with inflammatory or innate immune responses. Taken together, our findings show that recombinant biomimetics can be made that are at least two hundred-fold more effective than IVIG in controlling demyelination by anti-MOG antibodies.
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Affiliation(s)
- Christine Baksmeier
- Department of NeurologyMedical FacultyHeinrich‐Heine‐University DuesseldorfDuesseldorfGermany
| | - Pat Blundell
- Department of Tropical Disease BiologyLiverpool School of Tropical MedicineLiverpoolUK
| | - Julia Steckel
- Department of NeurologyMedical FacultyHeinrich‐Heine‐University DuesseldorfDuesseldorfGermany
| | - Verena Schultz
- Institute of Infection, Immunity and InflammationCollege of Medical Veterinary and Life SciencesUniversity of GlasgowGlasgowUK
| | - Quan Gu
- Institute of Infection, Immunity and InflammationCollege of Medical Veterinary and Life SciencesUniversity of GlasgowGlasgowUK
| | - Ana Da Silva Filipe
- Institute of Infection, Immunity and InflammationCollege of Medical Veterinary and Life SciencesUniversity of GlasgowGlasgowUK
| | - Alain Kohl
- Institute of Infection, Immunity and InflammationCollege of Medical Veterinary and Life SciencesUniversity of GlasgowGlasgowUK
| | - Chris Linnington
- Institute of Infection, Immunity and InflammationCollege of Medical Veterinary and Life SciencesUniversity of GlasgowGlasgowUK
| | - Dongli Lu
- Department of Life SciencesImperial College LondonLondonUK
| | - Anne Dell
- Department of Life SciencesImperial College LondonLondonUK
| | - Stuart Haslam
- Department of Life SciencesImperial College LondonLondonUK
| | - Jiabin Wang
- Shanghai Center for Systems BiomedicineKey Laboratory of Systems Biomedicine (Ministry of Education)Shanghai Jiao Tong UniversityShanghaiChina
| | - Dan Czajkowsky
- State Key Laboratory for Oncogenes and Related Genes and Bio‐ID CenterSchool of Biomedical EngineeringShanghai Jiao Tong UniversityShanghaiChina
| | - Norbert Goebels
- Department of NeurologyMedical FacultyHeinrich‐Heine‐University DuesseldorfDuesseldorfGermany
| | - Richard J. Pleass
- Department of Tropical Disease BiologyLiverpool School of Tropical MedicineLiverpoolUK
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Abstract
Pathogens frequently use multivalent binding to sialic acid to infect cells or to modulate immunity through interactions with human sialic acid-binding immunoglobulin-type lectins (Siglecs). Molecules that interfere with these interactions could be of interest as diagnostics, anti-infectives or as immune modulators. This review describes the development of molecular scaffolds based on the crystallizable fragment (Fc) region of immunoglobulin (Ig) G that deliver high-avidity binding to innate immune receptors, including sialic acid-dependent receptors. The ways in which the sialylated Fc may be engineered as immune modulators that mimic the anti-inflammatory properties of intravenous polyclonal Ig or as blockers of sialic-acid-dependent infectivity by viruses are also discussed.
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Affiliation(s)
- Richard J. Pleass
- Department of Tropical Disease Biology, Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool, UK
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3
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Ainsworth S, Menzies S, Pleass RJ. Animal derived antibodies should be considered alongside convalescent human plasma to deliver treatments for COVID-19. Wellcome Open Res 2020. [DOI: 10.12688/wellcomeopenres.15990.1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Published data on the first 5,000 coronavirus patients to receive plasma shows promise in the United States. However, delivering convalescent plasma therapies in low- and even middle-income countries is both difficult and costly. Here we discuss the advantages and disadvantages of antisera raised in animals that may allow poorer countries to control the devastating effects of COVID-19.
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4
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Blundell PA, Lu D, Dell A, Haslam S, Pleass RJ. Choice of Host Cell Line Is Essential for the Functional Glycosylation of the Fc Region of Human IgG1 Inhibitors of Influenza B Viruses. J Immunol 2020; 204:1022-1034. [PMID: 31907284 PMCID: PMC6994840 DOI: 10.4049/jimmunol.1901145] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Accepted: 12/02/2019] [Indexed: 12/11/2022]
Abstract
Abs are glycoproteins that carry a conserved N-linked carbohydrate attached to the Fc whose presence and fine structure profoundly impacts on their in vivo immunogenicity, pharmacokinetics, and functional attributes. The host cell line used to produce IgG plays a major role in this glycosylation, as different systems express different glycosylation enzymes and transporters that contribute to the specificity and heterogeneity of the final IgG-Fc glycosylation profile. In this study, we compare two panels of glycan-adapted IgG1-Fc mutants expressed in either the human endothelial kidney 293-F or Chinese hamster ovary-K1 systems. We show that the types of N-linked glycans between matched pairs of Fc mutants vary greatly and in particular, with respect, to sialylation. These cell line effects on glycosylation profoundly influence the ability of the engineered Fcs to interact with either human or pathogen receptors. For example, we describe Fc mutants that potently disrupted influenza B-mediated agglutination of human erythrocytes when expressed in Chinese hamster ovary-K1, but not in human endothelial kidney 293-F cells.
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Affiliation(s)
- Patricia A Blundell
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, United Kingdom; and
| | - Dongli Lu
- Department of Life Sciences, Imperial College London, London SW7 2AZ, United Kingdom
| | - Anne Dell
- Department of Life Sciences, Imperial College London, London SW7 2AZ, United Kingdom
| | - Stuart Haslam
- Department of Life Sciences, Imperial College London, London SW7 2AZ, United Kingdom
| | - Richard J Pleass
- Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, United Kingdom; and
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5
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Blundell PA, Lu D, Wilkinson M, Dell A, Haslam S, Pleass RJ. Insertion of N-Terminal Hinge Glycosylation Enhances Interactions of the Fc Region of Human IgG1 Monomers with Glycan-Dependent Receptors and Blocks Hemagglutination by the Influenza Virus. J Immunol 2019; 202:1595-1611. [PMID: 30683699 PMCID: PMC6379808 DOI: 10.4049/jimmunol.1801337] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Accepted: 12/29/2018] [Indexed: 11/28/2022]
Abstract
In therapeutic applications in which the Fc of IgG is critically important, the receptor binding and functional properties of the Fc are lost after deglycosylation or removal of the unique Asn297 N-X-(T/S) sequon. A population of Fcs bearing sialylated glycans has been identified as contributing to this functionality, and high levels of sialylation also lead to longer serum retention times advantageous for therapy. The efficacy of sialylated Fc has generated an incentive to modify the unique N-linked glycosylation site at Asn297, either through chemical and enzymatic methods or by mutagenesis of the Fc, that disrupts the protein-Asn297 carbohydrate interface. In this study, we took an alternative approach by inserting or deleting N-linked attachment sites into the body of the Fc to generate a portfolio of mutants with tailored effector functions. For example, we describe mutants with enhanced binding to low-affinity inhibitory human Fcγ and glycan receptors that may be usefully incorporated into existing Ab engineering approaches to treat or vaccinate against disease. The IgG1 Fc fragments containing complex sialylated glycans attached to the N-terminal Asn221 sequon bound influenza virus hemagglutinin and disrupted influenza A-mediated agglutination of human erythrocytes.
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Affiliation(s)
- Patricia A Blundell
- Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, United Kingdom; and
| | - Dongli Lu
- Department of Life Sciences, Imperial College London, London SW7 2AZ, United Kingdom
| | - Mark Wilkinson
- Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, United Kingdom; and
| | - Anne Dell
- Department of Life Sciences, Imperial College London, London SW7 2AZ, United Kingdom
| | - Stuart Haslam
- Department of Life Sciences, Imperial College London, London SW7 2AZ, United Kingdom
| | - Richard J Pleass
- Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, United Kingdom; and
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6
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Blundell PA, Le NPL, Allen J, Watanabe Y, Pleass RJ. Engineering the fragment crystallizable (Fc) region of human IgG1 multimers and monomers to fine-tune interactions with sialic acid-dependent receptors. J Biol Chem 2017; 292:12994-13007. [PMID: 28620050 PMCID: PMC5546038 DOI: 10.1074/jbc.m117.795047] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Revised: 06/12/2017] [Indexed: 12/24/2022] Open
Abstract
Multimeric fragment crystallizable (Fc) regions and Fc-fusion proteins are actively being explored as biomimetic replacements for IVIG therapy, which is deployed to manage many diseases and conditions but is expensive and not always efficient. The Fc region of human IgG1 (IgG1-Fc) can be engineered into multimeric structures (hexa-Fcs) that bind their cognate receptors with high avidity. The critical influence of the unique N-linked glycan attached at Asn-297 on the structure and function of IgG1-Fc is well documented; however, whether the N-linked glycan has a similarly critical role in multimeric, avidly binding Fcs, is unknown. Hexa-Fc contains two N-linked sites at Asn-77 (equivalent to Asn-297 in the Fc of IgG1) and Asn-236 (equivalent to Asn-563 in the tail piece of IgM). We report here that glycosylation at Asn-297 is critical for interactions with Fc receptors and complement and that glycosylation at Asn-563 is essential for controlling multimerization. We also found that introduction of an additional fully occupied N-linked glycosylation site at the N terminus at position 1 (equivalent to Asp-221 in the Fc of IgG1) dramatically enhances overall sialic acid content of the Fc multimers. Furthermore, replacement of Cys-575 in the IgM tail piece of multimers resulted in monomers with enhanced sialic acid content and differential receptor-binding profiles. Thus insertion of additional N-linked glycans into either the hinge or tail piece of monomers or multimers leads to molecules with enhanced sialylation that may be suitable for managing inflammation or blocking pathogen invasion.
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Affiliation(s)
- Patricia A Blundell
- Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, United Kingdom
| | - Ngoc Phuong Lan Le
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, United Kingdom
| | - Joel Allen
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, United Kingdom
| | - Yasunori Watanabe
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, United Kingdom
| | - Richard J Pleass
- Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, United Kingdom.
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7
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Crosnier C, Iqbal Z, Knuepfer E, Maciuca S, Perrin AJ, Kamuyu G, Goulding D, Bustamante LY, Miles A, Moore SC, Dougan G, Holder AA, Kwiatkowski DP, Rayner JC, Pleass RJ, Wright GJ. Binding of Plasmodium falciparum Merozoite Surface Proteins DBLMSP and DBLMSP2 to Human Immunoglobulin M Is Conserved among Broadly Diverged Sequence Variants. J Biol Chem 2016; 291:14285-14299. [PMID: 27226583 PMCID: PMC4933183 DOI: 10.1074/jbc.m116.722074] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Indexed: 11/17/2022] Open
Abstract
Diversity at pathogen genetic loci can be driven by host adaptive immune selection pressure and may reveal proteins important for parasite biology. Population-based genome sequencing of Plasmodium falciparum, the parasite responsible for the most severe form of malaria, has highlighted two related polymorphic genes called dblmsp and dblmsp2, which encode Duffy binding-like (DBL) domain-containing proteins located on the merozoite surface but whose function remains unknown. Using recombinant proteins and transgenic parasites, we show that DBLMSP and DBLMSP2 directly and avidly bind human IgM via their DBL domains. We used whole genome sequence data from over 400 African and Asian P. falciparum isolates to show that dblmsp and dblmsp2 exhibit extreme protein polymorphism in their DBL domain, with multiple variants of two major allelic classes present in every population tested. Despite this variability, the IgM binding function was retained across diverse sequence representatives. Although this interaction did not seem to have an effect on the ability of the parasite to invade red blood cells, binding of DBLMSP and DBLMSP2 to IgM inhibited the overall immunoreactivity of these proteins to IgG from patients who had been exposed to the parasite. This suggests that IgM binding might mask these proteins from the host humoral immune system.
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Affiliation(s)
- Cécile Crosnier
- Cell Surface Signalling Laboratory, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, United Kingdom; Malaria Programme, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, United Kingdom
| | - Zamin Iqbal
- Wellcome Trust Centre for Human Genetics, Oxford OX3 7BN, United Kingdom
| | - Ellen Knuepfer
- Francis Crick Institute, Mill Hill Laboratory, London NW7 1AA, United Kingdom
| | - Sorina Maciuca
- Wellcome Trust Centre for Human Genetics, Oxford OX3 7BN, United Kingdom
| | - Abigail J Perrin
- Cell Surface Signalling Laboratory, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, United Kingdom; Malaria Programme, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, United Kingdom
| | - Gathoni Kamuyu
- Malaria Programme, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, United Kingdom
| | - David Goulding
- Microbial Pathogenesis Laboratory, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, United Kingdom
| | - Leyla Y Bustamante
- Malaria Programme, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, United Kingdom
| | - Alistair Miles
- Malaria Programme, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, United Kingdom; Wellcome Trust Centre for Human Genetics, Oxford OX3 7BN, United Kingdom
| | - Shona C Moore
- Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, United Kingdom; Warwick Systems Biology Centre, Senate House, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Gordon Dougan
- Microbial Pathogenesis Laboratory, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, United Kingdom
| | - Anthony A Holder
- Francis Crick Institute, Mill Hill Laboratory, London NW7 1AA, United Kingdom
| | - Dominic P Kwiatkowski
- Malaria Programme, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, United Kingdom; Wellcome Trust Centre for Human Genetics, Oxford OX3 7BN, United Kingdom
| | - Julian C Rayner
- Malaria Programme, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, United Kingdom
| | - Richard J Pleass
- Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, United Kingdom
| | - Gavin J Wright
- Cell Surface Signalling Laboratory, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, United Kingdom; Malaria Programme, Wellcome Trust Sanger Institute, Cambridge CB10 1SA, United Kingdom.
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8
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Foss S, Grevys A, Sand KMK, Bern M, Blundell P, Michaelsen TE, Pleass RJ, Sandlie I, Andersen JT. Enhanced FcRn-dependent transepithelial delivery of IgG by Fc-engineering and polymerization. J Control Release 2015; 223:42-52. [PMID: 26718855 DOI: 10.1016/j.jconrel.2015.12.033] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Revised: 12/14/2015] [Accepted: 12/19/2015] [Indexed: 01/28/2023]
Abstract
Monoclonal IgG antibodies (Abs) are used extensively in the clinic to treat cancer and autoimmune diseases. In addition, therapeutic proteins are genetically fused to the constant Fc part of IgG. In both cases, the Fc secures a long serum half-life and favourable pharmacokinetics due to its pH-dependent interaction with the neonatal Fc receptor (FcRn). FcRn also mediates transport of intact IgG across polarized epithelial barriers, a pathway that is attractive for delivery of Fc-containing therapeutics. So far, no study has thoroughly compared side-by-side how IgG and different Fc-fusion formats are transported across human polarizing epithelial cells. Here, we used an in vitro cellular transport assay based on the human polarizing epithelial cell line (T84) in which both IgG1 and Fc-fusions were transported in an FcRn-dependent manner. Furthermore, we found that the efficacy of transport was dependent on the format. We demonstrate that transepithelial delivery could be enhanced by Fc-engineering for improved FcRn binding as well as by Fc-polymerization. In both cases, transport was driven by pH-dependent binding kinetics and the pH at the luminal side. Hence, efficient transcellular delivery of IgG-based drugs across human epithelial cells requires optimal pH-dependent FcRn binding that can be manipulated by avidity and Fc-engineering, factors that should inspire the design of future therapeutics targeted for transmucosal delivery.
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Affiliation(s)
- Stian Foss
- Centre for Immune Regulation (CIR), Department of Biosciences, University of Oslo, N-0316, Oslo, Norway; Department of Immunology and CIR, Oslo University Hospital, Rikshospitalet, University of Oslo, N-0372, Oslo, Norway
| | - Algirdas Grevys
- Centre for Immune Regulation (CIR), Department of Biosciences, University of Oslo, N-0316, Oslo, Norway; Department of Immunology and CIR, Oslo University Hospital, Rikshospitalet, University of Oslo, N-0372, Oslo, Norway
| | - Kine Marita Knudsen Sand
- Centre for Immune Regulation (CIR), Department of Biosciences, University of Oslo, N-0316, Oslo, Norway; Department of Immunology and CIR, Oslo University Hospital, Rikshospitalet, University of Oslo, N-0372, Oslo, Norway
| | - Malin Bern
- Centre for Immune Regulation (CIR), Department of Biosciences, University of Oslo, N-0316, Oslo, Norway; Department of Immunology and CIR, Oslo University Hospital, Rikshospitalet, University of Oslo, N-0372, Oslo, Norway
| | - Pat Blundell
- Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
| | - Terje E Michaelsen
- Department of Bacteriology and Immunology, Norwegian Institute of Public Health, Oslo, Norway; Department of Chemical Pharmacy, School of Pharmacy, University of Oslo, Oslo, Norway
| | - Richard J Pleass
- Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
| | - Inger Sandlie
- Centre for Immune Regulation (CIR), Department of Biosciences, University of Oslo, N-0316, Oslo, Norway; Department of Immunology and CIR, Oslo University Hospital, Rikshospitalet, University of Oslo, N-0372, Oslo, Norway
| | - Jan Terje Andersen
- Centre for Immune Regulation (CIR), Department of Biosciences, University of Oslo, N-0316, Oslo, Norway; Department of Immunology and CIR, Oslo University Hospital, Rikshospitalet, University of Oslo, N-0372, Oslo, Norway.
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9
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Pleass RJ, Moore SC, Stevenson L, Hviid L. Immunoglobulin M: Restrainer of Inflammation and Mediator of Immune Evasion by Plasmodium falciparum Malaria. Trends Parasitol 2015; 32:108-119. [PMID: 26597020 DOI: 10.1016/j.pt.2015.09.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Revised: 09/16/2015] [Accepted: 09/23/2015] [Indexed: 02/06/2023]
Abstract
Immunoglobulin M (IgM) is an ancient antibody class that is found in all vertebrates, with the exception of coelacanths, and is indispensable in both innate and adaptive immunity. The equally ancient human malaria parasite, Plasmodium falciparum, formed an intimate relationship with IgM with which it co-evolved. In this article, we discuss the association between IgM and human malaria parasites, building on several recent publications that implicate IgM as a crucial molecule that determines both host and parasite survival. Consequently, a better understanding of this association may lead to the development of improved intervention strategies.
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Affiliation(s)
- Richard J Pleass
- Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK.
| | - Shona C Moore
- Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK; Warwick Systems Biology Centre, Senate House, University of Warwick, Coventry, CV4 7AL, UK
| | - Liz Stevenson
- Centre for Medical Parasitology, Department of Immunology and Microbiology (ISIM), Faculty of Health and Medical Sciences, University of Copenhagen and Department of Infectious Diseases, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
| | - Lars Hviid
- Centre for Medical Parasitology, Department of Immunology and Microbiology (ISIM), Faculty of Health and Medical Sciences, University of Copenhagen and Department of Infectious Diseases, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark.
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10
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Llewellyn D, Miura K, Fay MP, Williams AR, Murungi LM, Shi J, Hodgson SH, Douglas AD, Osier FH, Fairhurst RM, Diakite M, Pleass RJ, Long CA, Draper SJ. Standardization of the antibody-dependent respiratory burst assay with human neutrophils and Plasmodium falciparum malaria. Sci Rep 2015; 5:14081. [PMID: 26373337 PMCID: PMC4571651 DOI: 10.1038/srep14081] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Accepted: 08/17/2015] [Indexed: 01/09/2023] Open
Abstract
The assessment of naturally-acquired and vaccine-induced immunity to blood-stage Plasmodium falciparum malaria is of long-standing interest. However, the field has suffered from a paucity of in vitro assays that reproducibly measure the anti-parasitic activity induced by antibodies in conjunction with immune cells. Here we optimize the antibody-dependent respiratory burst (ADRB) assay, which assesses the ability of antibodies to activate the release of reactive oxygen species from human neutrophils in response to P. falciparum blood-stage parasites. We focus particularly on assay parameters affecting serum preparation and concentration, and importantly assess reproducibility. Our standardized protocol involves testing each serum sample in singlicate with three independent neutrophil donors, and indexing responses against a standard positive control of pooled hyper-immune Kenyan sera. The protocol can be used to quickly screen large cohorts of samples from individuals enrolled in immuno-epidemiological studies or clinical vaccine trials, and requires only 6 μL of serum per sample. Using a cohort of 86 samples, we show that malaria-exposed individuals induce higher ADRB activity than malaria-naïve individuals. The development of the ADRB assay complements the use of cell-independent assays in blood-stage malaria, such as the assay of growth inhibitory activity, and provides an important standardized cell-based assay in the field.
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Affiliation(s)
- David Llewellyn
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, OX3 7DQ, UK
| | - Kazutoyo Miura
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, 20852, USA
| | - Michael P. Fay
- Biostatistics Research Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, USA
| | - Andrew R. Williams
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, OX3 7DQ, UK
| | - Linda M. Murungi
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, OX3 7DQ, UK
- KEMRI Centre for Geographic Medicine Research, Coast, P.O. Box 230-80108, Kilifi, Kenya
| | - Jianguo Shi
- Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Susanne H. Hodgson
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, OX3 7DQ, UK
| | - Alexander D. Douglas
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, OX3 7DQ, UK
| | - Faith H. Osier
- KEMRI Centre for Geographic Medicine Research, Coast, P.O. Box 230-80108, Kilifi, Kenya
| | - Rick M. Fairhurst
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, 20852, USA
| | - Mahamadou Diakite
- Malaria Research and Training Centre, Faculty of Medicine, Pharmacy and Odonto-stomatology, University of Bamako, Bamako, Mali
| | - Richard J. Pleass
- Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Carole A. Long
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, 20852, USA
| | - Simon J. Draper
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, OX3 7DQ, UK
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11
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Czajkowsky DM, Andersen JT, Fuchs A, Wilson TJ, Mekhaiel D, Colonna M, He J, Shao Z, Mitchell DA, Wu G, Dell A, Haslam S, Lloyd KA, Moore SC, Sandlie I, Blundell PA, Pleass RJ. Developing the IVIG biomimetic, hexa-Fc, for drug and vaccine applications. Sci Rep 2015; 5:9526. [PMID: 25912958 PMCID: PMC5224519 DOI: 10.1038/srep09526] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Accepted: 02/26/2015] [Indexed: 12/20/2022] Open
Abstract
The remarkable clinical success of Fc-fusion proteins has driven intense investigation for even more potent replacements. Using quality-by-design (QbD) approaches, we generated hexameric-Fc (hexa-Fc), a ~20 nm oligomeric Fc-based scaffold that we here show binds low-affinity inhibitory receptors (FcRL5, FcγRIIb, and DC-SIGN) with high avidity and specificity, whilst eliminating significant clinical limitations of monomeric Fc-fusions for vaccine and/or cancer therapies, in particular their poor ability to activate complement. Mass spectroscopy of hexa-Fc reveals high-mannose, low-sialic acid content, suggesting that interactions with these receptors are influenced by the mannose-containing Fc. Molecular dynamics (MD) simulations provides insight into the mechanisms of hexa-Fc interaction with these receptors and reveals an unexpected orientation of high-mannose glycans on the human Fc that provides greater accessibility to potential binding partners. Finally, we show that this biosynthetic nanoparticle can be engineered to enhance interactions with the human neonatal Fc receptor (FcRn) without loss of the oligomeric structure, a crucial modification for these molecules in therapy and/or vaccine strategies where a long plasma half-life is critical.
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Affiliation(s)
- Daniel M Czajkowsky
- Bio-ID Center, School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, 200240 P. R. China
| | - Jan Terje Andersen
- Centre for Immune Regulation (CIR) and Department of Immunology, Oslo University Hospital Rikshospitalet, P.O. Box 4956, Oslo N-0424, Norway
| | - Anja Fuchs
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Timothy J Wilson
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - David Mekhaiel
- Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Marco Colonna
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Jianfeng He
- Bio-ID Center, School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, 200240 P. R. China
| | - Zhifeng Shao
- Bio-ID Center, School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, 200240 P. R. China
| | - Daniel A Mitchell
- Clinical Sciences Research Laboratories, Warwick Medical School, University of Warwick, Coventry CV2 2DX, UK
| | - Gang Wu
- Department of Life Sciences, Imperial College London, South Kensington Campus, London SW7
| | - Anne Dell
- Department of Life Sciences, Imperial College London, South Kensington Campus, London SW7
| | - Stuart Haslam
- Department of Life Sciences, Imperial College London, South Kensington Campus, London SW7
| | - Katy A Lloyd
- Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Shona C Moore
- Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Inger Sandlie
- 1] Centre for Immune Regulation (CIR) and Department of Immunology, Oslo University Hospital Rikshospitalet, P.O. Box 4956, Oslo N-0424, Norway [2] CIR and Department of Biosciences, University of Oslo, N-0316 Oslo, Norway
| | - Patricia A Blundell
- Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Richard J Pleass
- Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
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12
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Llewellyn D, de Cassan SC, Williams AR, Douglas AD, Forbes EK, Adame-Gallegos JR, Shi J, Pleass RJ, Draper SJ. Assessment of antibody-dependent respiratory burst activity from mouse neutrophils on Plasmodium yoelii malaria challenge outcome. J Leukoc Biol 2014; 95:369-82. [PMID: 24163420 PMCID: PMC3896657 DOI: 10.1189/jlb.0513274] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Revised: 09/23/2013] [Accepted: 10/01/2013] [Indexed: 01/12/2023] Open
Abstract
New tools are required to expedite the development of an effective vaccine against the blood-stage infection with the human malaria parasite Plasmodium falciparum. This work describes the assessment of the ADRB assay in a mouse model, characterizing the functional interaction between antimalarial serum antibodies and FcRs upon neutrophils. We describe a reproducible, antigen-specific assay, dependent on functional FcR signaling, and show that ADRB activity is induced equally by IgG1 and IgG2a isotypes and is modulated by blocking FcR function. However, following immunization of mice with the blood-stage vaccine candidate antigen MSP142, no measurable ADRB activity was induced against PEMS and neither was vaccine efficacy modulated against Plasmodium yoelii blood-stage challenge in γ(-/-) mice compared with WT mice. In contrast, following a primary, nonlethal P. yoelii parasite challenge, serum from vaccinated mice and nonimmunized controls showed anti-PEMS ADRB activity. Upon secondary challenge, nonimmunized γ(-/-) mice showed a reduced ability to control blood-stage parasitemia compared with immunized γ(-/-) mice; however, WT mice, depleted of their neutrophils, did not lose their ability to control infection. Thus, whereas neutrophil-induced ADRB against PEMS does not appear to play a role in protection against P. yoelii rodent malaria, induction of ADRB activity after challenge suggests that antigen targets of anti-PEMS ADRB activity remain to be established, as well as further supporting the observation that ADRB activity to P. falciparum arises following repeated natural exposure.
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Affiliation(s)
- David Llewellyn
- 1.University of Oxford, Old Road Campus Research Building, Oxford, OX3 7DQ, UK.
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13
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Islahudin F, Tindall SM, Mellor IR, Swift K, Christensen HEM, Fone KCF, Pleass RJ, Ting KN, Avery SV. The antimalarial drug quinine interferes with serotonin biosynthesis and action. Sci Rep 2014; 4:3618. [PMID: 24402577 PMCID: PMC3885885 DOI: 10.1038/srep03618] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Accepted: 12/10/2013] [Indexed: 02/02/2023] Open
Abstract
The major antimalarial drug quinine perturbs uptake of the essential amino acid tryptophan, and patients with low plasma tryptophan are predisposed to adverse quinine reactions; symptoms of which are similar to indications of tryptophan depletion. As tryptophan is a precursor of the neurotransmitter serotonin (5-HT), here we test the hypothesis that quinine disrupts serotonin function. Quinine inhibited serotonin-induced proliferation of yeast as well as human (SHSY5Y) cells. One possible cause of this effect is through inhibition of 5-HT receptor activation by quinine, as we observed here. Furthermore, cells exhibited marked decreases in serotonin production during incubation with quinine. By assaying activity and kinetics of the rate-limiting enzyme for serotonin biosynthesis, tryptophan hydroxylase (TPH2), we showed that quinine competitively inhibits TPH2 in the presence of the substrate tryptophan. The study shows that quinine disrupts both serotonin biosynthesis and function, giving important new insight to the action of quinine on mammalian cells.
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Affiliation(s)
- Farida Islahudin
- School of Life Sciences, University of Nottingham, Nottingham NG7 2RD, UK
- School of Pharmacy, University of Nottingham Malaysia Campus, 43500 Semenyih, Malaysia
- Current address: Faculty of Pharmacy, University of Kebangsaan Malaysia, 50300, Kuala Lumpur, Malaysia
| | - Sarah M. Tindall
- School of Life Sciences, University of Nottingham, Nottingham NG7 2RD, UK
| | - Ian R. Mellor
- School of Life Sciences, University of Nottingham, Nottingham NG7 2RD, UK
| | - Karen Swift
- School of Life Sciences, University of Nottingham, Nottingham NG7 2RD, UK
| | | | - Kevin C. F. Fone
- School of Life Sciences, University of Nottingham, Nottingham NG7 2RD, UK
| | - Richard J. Pleass
- University of Liverpool, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK
| | - Kang-Nee Ting
- School of Life Sciences, University of Nottingham Malaysia Campus, 43500 Semenyih, Malaysia
| | - Simon V. Avery
- School of Life Sciences, University of Nottingham, Nottingham NG7 2RD, UK
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14
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Goodman AL, Forbes EK, Williams AR, Douglas AD, de Cassan SC, Bauza K, Biswas S, Dicks MDJ, Llewellyn D, Moore AC, Janse CJ, Franke-Fayard BM, Gilbert SC, Hill AVS, Pleass RJ, Draper SJ. The utility of Plasmodium berghei as a rodent model for anti-merozoite malaria vaccine assessment. Sci Rep 2013; 3:1706. [PMID: 23609325 PMCID: PMC3632886 DOI: 10.1038/srep01706] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Accepted: 04/08/2013] [Indexed: 12/17/2022] Open
Abstract
Rodent malaria species Plasmodium yoelii and P. chabaudi have been widely used to validate vaccine approaches targeting blood-stage merozoite antigens. However, increasing data suggest the P. berghei rodent malaria may be able to circumvent vaccine-induced anti-merozoite responses. Here we confirm a failure to protect against P. berghei, despite successful antibody induction against leading merozoite antigens using protein-in-adjuvant or viral vectored vaccine delivery. No subunit vaccine approach showed efficacy in mice following immunization and challenge with the wild-type P. berghei strains ANKA or NK65, or against a chimeric parasite line encoding a merozoite antigen from P. falciparum. Protection was not improved in knockout mice lacking the inhibitory Fc receptor CD32b, nor against a Δsmac P. berghei parasite line with a non-sequestering phenotype. An improved understanding of the mechanisms responsible for protection, or failure of protection, against P. berghei merozoites could guide the development of an efficacious vaccine against P. falciparum.
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Affiliation(s)
- Anna L Goodman
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, UK.
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15
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Edwards-Smallbone J, Pleass RJ, Khan NA, Flynn RJ. Acanthamoeba interactions with the blood–brain barrier under dynamic fluid flow. Exp Parasitol 2012; 132:367-72. [DOI: 10.1016/j.exppara.2012.08.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2012] [Revised: 08/14/2012] [Accepted: 08/20/2012] [Indexed: 10/27/2022]
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16
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Forbes EK, de Cassan SC, Llewellyn D, Biswas S, Goodman AL, Cottingham MG, Long CA, Pleass RJ, Hill AVS, Hill F, Draper SJ. T cell responses induced by adenoviral vectored vaccines can be adjuvanted by fusion of antigen to the oligomerization domain of C4b-binding protein. PLoS One 2012; 7:e44943. [PMID: 22984589 PMCID: PMC3440343 DOI: 10.1371/journal.pone.0044943] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2011] [Accepted: 08/14/2012] [Indexed: 11/18/2022] Open
Abstract
Viral vectored vaccines have been shown to induce both T cell and antibody responses in animals and humans. However, the induction of even higher level T cell responses may be crucial in achieving vaccine efficacy against difficult disease targets, especially in humans. Here we investigate the oligomerization domain of the α-chain of C4b-binding protein (C4 bp) as a candidate T cell "molecular adjuvant" when fused to malaria antigens expressed by human adenovirus serotype 5 (AdHu5) vectored vaccines in BALB/c mice. We demonstrate that i) C-terminal fusion of an oligomerization domain can enhance the quantity of antigen-specific CD4(+) and CD8(+) T cell responses induced in mice after only a single immunization of recombinant AdHu5, and that the T cells maintain similar functional cytokine profiles; ii) an adjuvant effect is observed for AdHu5 vectors expressing either the 42 kDa C-terminal domain of Plasmodium yoelii merozoite surface protein 1 (PyMSP1(42)) or the 83 kDa ectodomain of P. falciparum strain 3D7 apical membrane antigen 1 (PfAMA1), but not a candidate 128kDa P. falciparum MSP1 biallelic fusion antigen; iii) following two homologous immunizations of AdHu5 vaccines, antigen-specific T cell responses are further enhanced, however, in both BALB/c mice and New Zealand White rabbits no enhancement of functional antibody responses is observed; and iv) that the T cell adjuvant activity of C4 bp is not dependent on a functional Fc-receptor γ-chain in the host, but is associated with the oligomerization of small (<80 kDa) antigens expressed by recombinant AdHu5. The oligomerization domain of C4 bp can thus adjuvant T cell responses induced by AdHu5 vectors against selected antigens and its clinical utility as well as mechanism of action warrant further investigation.
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Affiliation(s)
- Emily K. Forbes
- The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | | | - David Llewellyn
- The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Sumi Biswas
- The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | - Anna L. Goodman
- The Jenner Institute, University of Oxford, Oxford, United Kingdom
| | | | - Carole A. Long
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases/National Institutes of Health, Rockville, Maryland, United States of America
| | | | | | | | - Simon J. Draper
- The Jenner Institute, University of Oxford, Oxford, United Kingdom
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17
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Czajkowsky DM, Hu J, Shao Z, Pleass RJ. Fc-fusion proteins: new developments and future perspectives. EMBO Mol Med 2012; 4:1015-28. [PMID: 22837174 PMCID: PMC3491832 DOI: 10.1002/emmm.201201379] [Citation(s) in RCA: 316] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Revised: 05/29/2012] [Accepted: 06/15/2012] [Indexed: 12/25/2022] Open
Abstract
Since the first description in 1989 of CD4-Fc-fusion antagonists that inhibit human immune deficiency virus entry into T cells, Fc-fusion proteins have been intensely investigated for their effectiveness to curb a range of pathologies, with several notable recent successes coming to market. These promising outcomes have stimulated the development of novel approaches to improve their efficacy and safety, while also broadening their clinical remit to other uses such as vaccines and intravenous immunoglobulin therapy. This increased attention has also led to non-clinical applications of Fc-fusions, such as affinity reagents in microarray devices. Here we discuss recent results and more generally applicable strategies to improve Fc-fusion proteins for each application, with particular attention to the newer, less charted areas.
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Affiliation(s)
- Daniel M Czajkowsky
- Key Laboratory of Systems Biomedicine (Ministry of Education) & State Key Laboratory of Oncogenes & Related Genes, Shanghai Jiao Tong University, Shanghai, P. R. China
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18
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Islahudin F, Pleass RJ, Avery SV, Ting KN. Quinine interactions with tryptophan and tyrosine in malaria patients, and implications for quinine responses in the clinical setting. J Antimicrob Chemother 2012; 67:2501-5. [PMID: 22763566 DOI: 10.1093/jac/dks253] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVES Recent work with the yeast model revealed that the antiprotozoal drug quinine competes with tryptophan for uptake via a common transport protein, causing cellular tryptophan starvation. In the present work, it was hypothesized that similar interactions may occur in malaria patients receiving quinine therapy. PATIENTS AND METHODS A direct observational study was conducted in which plasma levels of drug and amino acids (tryptophan, tyrosine and phenylalanine) were monitored during quinine treatment of malaria patients with Plasmodium falciparum infections. RESULTS Consistent with competition for uptake from plasma into cells, plasma tryptophan and tyrosine levels increased ≥2-fold during quinine therapy. Plasma quinine levels in individual plasma samples were significantly and positively correlated with tryptophan and tyrosine in the same samples. Control studies indicated no effect on phenylalanine. Chloroquine treatment of Plasmodium vivax-infected patients did not affect plasma tryptophan or tyrosine. During quinine treatment, plasma tryptophan was significantly lower (and quinine significantly higher) in patients experiencing adverse drug reactions. CONCLUSIONS Plasma quinine levels during therapy are related to patient tryptophan and tyrosine levels, and these interactions can determine patient responses to quinine. The study also highlights the potential for extrapolating insights directly from the yeast model to human malaria patients.
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Affiliation(s)
- Farida Islahudin
- School of Pharmacy, University of Nottingham Malaysia Campus, 43500 Semenyih, Malaysia
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19
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Harrison R, Hitchen PG, Panico M, Morris HR, Mekhaiel D, Pleass RJ, Dell A, Hewitt JE, Haslam SM. Glycoproteomic characterization of recombinant mouse α-dystroglycan. Glycobiology 2012; 22:662-75. [PMID: 22241827 PMCID: PMC3311285 DOI: 10.1093/glycob/cws002] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2011] [Revised: 01/04/2012] [Accepted: 01/04/2012] [Indexed: 12/15/2022] Open
Abstract
α-Dystroglycan (DG) is a key component of the dystrophin-glycoprotein complex. Aberrant glycosylation of the protein has been linked to various forms of congenital muscular dystrophy. Unusually α-DG has previously been demonstrated to be modified with both O-N-acetylgalactosamine and O-mannose initiated glycans. In the present study, Fc-tagged recombinant mouse α-DG was expressed and purified from human embryonic kidney 293T cells. α-DG glycopeptides were characterized by glycoproteomic strategies using both nano-liquid chromatography matrix-assisted laser desorption ionization and electrospray tandem mass spectrometry. A total of 14 different peptide sequences and 38 glycopeptides were identified which displayed heterogeneous O-glycosylation. These data provide new insights into the complex domain-specific O-glycosylation of α-DG.
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Affiliation(s)
- Rebecca Harrison
- Division of Molecular Biosciences, Faculty of Natural Sciences, Imperial College London, London SW7 2AZ, UK
| | - Paul G Hitchen
- Division of Molecular Biosciences, Faculty of Natural Sciences, Imperial College London, London SW7 2AZ, UK
| | - Maria Panico
- Division of Molecular Biosciences, Faculty of Natural Sciences, Imperial College London, London SW7 2AZ, UK
| | - Howard R Morris
- Division of Molecular Biosciences, Faculty of Natural Sciences, Imperial College London, London SW7 2AZ, UK
| | - David Mekhaiel
- Centre for Genetics and Genomics, School of Biology, Queen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UK
| | - Richard J Pleass
- Centre for Genetics and Genomics, School of Biology, Queen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UK
| | - Anne Dell
- Division of Molecular Biosciences, Faculty of Natural Sciences, Imperial College London, London SW7 2AZ, UK
| | - Jane E Hewitt
- Centre for Genetics and Genomics, School of Biology, Queen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UK
| | - Stuart M Haslam
- Division of Molecular Biosciences, Faculty of Natural Sciences, Imperial College London, London SW7 2AZ, UK
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20
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Adame-Gallegos JR, Shi J, McIntosh RS, Pleass RJ. The generation and evaluation of two panels of epitope-matched mouse IgG1, IgG2a, IgG2b and IgG3 antibodies specific for Plasmodium falciparum and Plasmodium yoelii merozoite surface protein 1-19 (MSP1(19)). Exp Parasitol 2012; 130:384-93. [PMID: 22343045 PMCID: PMC3336205 DOI: 10.1016/j.exppara.2012.02.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2011] [Revised: 01/28/2012] [Accepted: 02/02/2012] [Indexed: 11/28/2022]
Abstract
Murine immunoglobulin G (IgG) plays an important role in mediating protective immune responses to malaria. We still know relatively little about which IgG subclasses protect against this disease in mouse models, although IgG2a and IgG2b are considered to be the most potent and dominate in successful passive transfer experiments in rodent malarias. To explore the mechanism(s) by which the different mouse IgG subclasses may mediate a protective effect, we generated mouse IgG1, IgG2a, IgG2b and IgG3 specific for the C-terminal 19-kDa region of Plasmodium falciparum merozoite surface protein 1 (PfMSP119), and to the homologous antigen from Plasmodium yoelii (P. yoelii), both major targets of protective immune responses. This panel of eight IgGs bound antigen with an affinity comparable to that seen for their epitope-matched parental monoclonal antibodies (mAbs) from which they were derived, although for reasons of yield, we were only able to explore the function of mouse IgG1 recognizing PfMSP119 in detail, both in vitro and in vivo. Murine IgG1 was as effective as the parental human IgG from which it was derived at inducing NADPH-mediated oxidative bursts and degranulation from neutrophils. Despite showing efficacy in in vitro functional assays with neutrophils, the mouse IgG1 failed to protect against parasite challenge in vivo. The lack of protection afforded by MSP119-specific IgG1 against parasite challenge in wild type mice suggests that this Ab class does not play a major role in the control of infection with mouse malaria in the Plasmodium berghei transgenic model.
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Affiliation(s)
- Jaime R Adame-Gallegos
- Lab C4, Institute of Genetics, Queen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UK.
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21
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Mekhaiel DNA, Czajkowsky DM, Andersen JT, Shi J, El-Faham M, Doenhoff M, McIntosh RS, Sandlie I, He J, Hu J, Shao Z, Pleass RJ. Polymeric human Fc-fusion proteins with modified effector functions. Sci Rep 2011; 1:124. [PMID: 22355641 PMCID: PMC3216605 DOI: 10.1038/srep00124] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2011] [Accepted: 10/03/2011] [Indexed: 12/21/2022] Open
Abstract
The success of Fc-fusion bio-therapeutics has spurred the development of other Fc-fusion products for treating and/or vaccinating against a range of diseases. We describe a method to modulate their function by converting them into well-defined stable polymers. This strategy resulted in cylindrical hexameric structures revealed by tapping mode atomic force microscopy (AFM). Polymeric Fc-fusions were significantly less immunogenic than their dimeric or monomeric counterparts, a result partly owing to their reduced ability to interact with critical Fc-receptors. However, in the absence of the fusion partner, polymeric IgG1-Fc molecules were capable of binding selectively to FcγRs, with significantly increased affinity owing to their increased valency, suggesting that these reagents may prove of immediate utility in the development of well-defined replacements for intravenous immunoglobulin (IVIG) therapy. Overall, these findings establish an effective IgG Fc-fusion based polymeric platform with which the therapeutic and vaccination applications of Fc-fusion immune-complexes can now be explored.
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Affiliation(s)
- David N A Mekhaiel
- Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
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22
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Mekhaiel DNA, Daniel-Ribeiro CT, Cooper PJ, Pleass RJ. Do regulatory antibodies offer an alternative mechanism to explain the hygiene hypothesis? Trends Parasitol 2011; 27:523-9. [PMID: 21943801 DOI: 10.1016/j.pt.2011.08.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2011] [Revised: 08/17/2011] [Accepted: 08/18/2011] [Indexed: 12/24/2022]
Abstract
The 'hygiene hypothesis', or lack of microbial and parasite exposure during early life, is postulated as an explanation for the recent increase in autoimmune and allergic diseases in developed countries. The favored mechanism is that microbial and parasite-derived products interact directly with pathogen recognition receptors to subvert proinflammatory signaling via T regulatory cells, thereby inducing anti-inflammatory effects and control of autoimmune disease. Parasites, such as helminths, are considered to have a major role in the induction of immune regulatory mechanisms among children living in developing countries. Invoking Occam's razor, we believe we can select an alternative mechanism to explain the hygiene hypothesis, based on antibody-mediated inhibition of immune responses that may more simply explain the available evidence.
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Affiliation(s)
- David N A Mekhaiel
- Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
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23
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Whyteside G, Alcocer MJC, Kumita JR, Dobson CM, Lazarou M, Pleass RJ, Archer DB. Native-state stability determines the extent of degradation relative to secretion of protein variants from Pichia pastoris. PLoS One 2011; 6:e22692. [PMID: 21818368 PMCID: PMC3144928 DOI: 10.1371/journal.pone.0022692] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2011] [Accepted: 06/29/2011] [Indexed: 12/31/2022] Open
Abstract
We have investigated the relationship between the stability and secreted yield of a series of mutational variants of human lysozyme (HuL) in Pichia pastoris. We show that genes directly involved in the unfolded protein response (UPR), ER-associated degradation (ERAD) and ER-phagy are transcriptionally up-regulated more quickly and to higher levels in response to expression of more highly-destabilised HuL variants and those variants are secreted to lower yield. We also show that the less stable variants are retained within the cell and may also be targeted for degradation. To explore the relationship between stability and secretion further, two different single-chain-variable-fragment (scFv) antibodies were also expressed in P. pastoris, but only one of the scFvs gave rise to secreted protein. The non-secreted scFv was detected within the cell and the UPR indicators were pronounced, as they were for the poorly-secreted HuL variants. The non-secreted scFv was modified by changing either the framework regions or the linker to improve the predicted stability of the scFv and secretion was then achieved and the levels of UPR indicators were lowered Our data support the hypothesis that less stable proteins are targeted for degradation over secretion and that this accounts for the decrease in the yields observed. We discuss the secretion of proteins in relation to lysozyme amyloidosis, in particular, and optimised protein secretion, in general.
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Affiliation(s)
- Graham Whyteside
- School of Biology, University of Nottingham, Nottingham, United Kingdom
| | - Marcos J. C. Alcocer
- School of Biosciences, University of Nottingham, Sutton Bonington, United Kingdom
| | - Janet R. Kumita
- Department of Chemistry, University of Cambridge, Cambridge, United Kingdom
| | | | - Maria Lazarou
- School of Biology, University of Nottingham, Nottingham, United Kingdom
- Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Richard J. Pleass
- School of Biology, University of Nottingham, Nottingham, United Kingdom
- Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - David B. Archer
- School of Biology, University of Nottingham, Nottingham, United Kingdom
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24
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Shi J, McIntosh RS, Adame-Gallegos J, Dehal PK, van Egmond M, van de Winkel J, Draper SJ, Forbes EK, Corran PH, Holder AA, Woof JM, Pleass RJ. The generation and evaluation of recombinant human IgA specific for Plasmodium falciparum merozoite surface protein 1-19 (PfMSP1 19). BMC Biotechnol 2011; 11:77. [PMID: 21781305 PMCID: PMC3199766 DOI: 10.1186/1472-6750-11-77] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2011] [Accepted: 07/22/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Human immunoglobulin G (IgG) plays an important role in mediating protective immune responses to malaria. Although human serum immunoglobulin A (IgA) is the second most abundant class of antibody in the circulation, its contribution, if any, to protective responses against malaria is not clear. RESULTS To explore the mechanism(s) by which IgA may mediate a protective effect, we generated fully human IgA specific for the C-terminal 19-kDa region of Plasmodium falciparum merozoite surface protein 1 (PfMSP1 19), a major target of protective immune responses. This novel human IgA bound antigen with an affinity comparable to that seen for an epitope-matched protective human IgG1. Furthermore, the human IgA induced significantly higher NADPH-mediated oxidative bursts and degranulation from human neutrophils than the epitope-matched human IgG1 from which it was derived. Despite showing efficacy in in vitro functional assays, the human IgA failed to protect against parasite challenge in vivo in mice transgenic for the human Fcα receptor (FcαRI/CD89). A minority of the animals treated with IgA, irrespective of FcαRI expression, showed elevated serum TNF-α levels and concomitant mouse anti-human antibody (MAHA) responses. CONCLUSIONS The lack of protection afforded by MSP1 19-specific IgA against parasite challenge in mice transgenic for human FcαRI suggests that this antibody class does not play a major role in control of infection. However, we cannot exclude the possibility that protective capacity may have been compromised in this model due to rapid clearance and inappropriate bio-distribution of IgA, and differences in FcαRI expression profile between humans and transgenic mice.
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Affiliation(s)
- Jianguo Shi
- Institute of Genetics, Queen's Medical Centre, University of Nottingham, NG7 2UH, UK
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Balu S, Reljic R, Lewis MJ, Pleass RJ, McIntosh R, van Kooten C, van Egmond M, Challacombe S, Woof JM, Ivanyi J. A novel human IgA monoclonal antibody protects against tuberculosis. J Immunol 2011; 186:3113-9. [PMID: 21257971 DOI: 10.4049/jimmunol.1003189] [Citation(s) in RCA: 128] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Abs have been shown to be protective in passive immunotherapy of tuberculous infection using mouse experimental models. In this study, we report on the properties of a novel human IgA1, constructed using a single-chain variable fragment clone (2E9), selected from an Ab phage library. The purified Ab monomer revealed high binding affinities for the mycobacterial α-crystallin Ag and for the human FcαRI (CD89) IgA receptor. Intranasal inoculations with 2E9IgA1 and recombinant mouse IFN-γ significantly inhibited pulmonary H37Rv infection in mice transgenic for human CD89 but not in CD89-negative littermate controls, suggesting that binding to CD89 was necessary for the IgA-imparted passive protection. 2E9IgA1 added to human whole-blood or monocyte cultures inhibited luciferase-tagged H37Rv infection although not for all tested blood donors. Inhibition by 2E9IgA1 was synergistic with human rIFN-γ in cultures of purified human monocytes but not in whole-blood cultures. The demonstration of the mandatory role of FcαRI (CD89) for human IgA-mediated protection is important for understanding of the mechanisms involved and also for translation of this approach toward development of passive immunotherapy of tuberculosis.
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Affiliation(s)
- Sucharitha Balu
- Clinical and Diagnostic Sciences Group, Guy's Campus of Kings College London, London SE1 9RT, United Kingdom
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26
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Abstract
IgM is an ancestral Ab class found in all jawed vertebrates, from sharks to mammals. This ancient ancestry is shared by malaria parasites (genus Plasmodium) that infect all classes of terrestrial vertebrates with whom they coevolved. IgM, the least studied and most enigmatic of the vertebrate Igs, was recently shown to form an intimate relationship with the malaria parasite Plasmodium falciparum. In this article, we discuss how this association might have come about, building on the recently determined structure of the human IgM pentamer, and how this interaction could affect parasite survival, particularly in light of the just-discovered Fc mu R localized to B and T cell surfaces. Because this parasite may exploit an interaction with IgM to limit immune detection, as well as to manipulate the immune response when detected, a better understanding of this association may prove critical for the development of improved vaccines or vaccination strategies.
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Affiliation(s)
- Daniel M. Czajkowsky
- Department of Molecular Physiology & Biological Physics, University of Virginia Health Sciences Center, P. O. Box 800736, Charlottesville, VA 22908, USA
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, 201800, China
| | - Ali Salanti
- Centre for Medical Parasitology at Department of International Health, Immunology, and Microbiology, University of Copenhagen, Copenhagen University Hospital, Rigshospitalet, DK
| | - Sisse B Ditlev
- Centre for Medical Parasitology at Department of International Health, Immunology, and Microbiology, University of Copenhagen, Copenhagen University Hospital, Rigshospitalet, DK
| | - Zhifeng Shao
- Department of Molecular Physiology & Biological Physics, University of Virginia Health Sciences Center, P. O. Box 800736, Charlottesville, VA 22908, USA
- MOE Key Lab for Systems Biomedicine and National Lab for Oncogenes, Shanghai JiaoTong University, Shanghai 200240, China
| | - Ashfaq Ghumra
- Institute of Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh, Scotland, UK
- Institute of Genetics, and Parasite Biology and Immunogenetics Research Group, Queen’s Medical Centre, University of Nottingham, NG7 2UH, UK
| | - J. Alexandra Rowe
- Institute of Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh, Scotland, UK
| | - Richard J Pleass
- Institute of Genetics, and Parasite Biology and Immunogenetics Research Group, Queen’s Medical Centre, University of Nottingham, NG7 2UH, UK
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27
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Abstract
The complexity and number of antigens (Ags) seen during an immune response has hampered the development of malaria vaccines. Antibodies (Abs) play an important role in immunity to malaria and their passive administration is effective at controlling the disease. Abs represent approximately 25% of all proteins undergoing clinical trials, and these 'smart biologicals' have undergone a major revival with the realization that Abs lie at the interface between innate and adaptive immunity. At least 18 Abs have FDA approval for clinical use and approximately 150 are in clinical trials, the majority for the treatment of cancer, allograft rejection or autoimmune disease. Despite these triumphs none are in development for malaria, principally because they are perceived as being too expensive for a disease mainly afflicting poor and marginalized populations. Although unlikely, at least in the foreseeable future, that Ab-based prophylaxis will be made available to the millions of people at risk from malaria, they may be incorporated into current vaccine approaches, since Abs act as correlates of protection in studies aimed at defining the best Ags to include in vaccines. Abs may also form the basis for novel vaccination strategies by targeting Ags to appropriate antigen presenting cells. Therefore, to develop the most efficacious vaccines it will be necessary to fully understand which Abs and Fc-receptors (FcRs) are best engaged for a positive outcome.
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Affiliation(s)
- R J Pleass
- Institute of Genetics, Queen's Medical Centre, Nottingham NG7 2UH, UK.
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28
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Abstract
Two recent papers published in Immunity and Cell Host & Microbe underline the great importance of B cells and of antibodies (Abs) in orchestrating crucial T helper cell type 2 (Th2) protective immune responses to gastrointestinal nematodes. The findings in animal models now raise major questions as to how B cells and Abs carry out these functions in humans. Here we discuss recent technological advances in humanizing animal models at the level of both Abs and their Fc-receptors, that might provide some answers.
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Affiliation(s)
- Richard J Pleass
- Institute of Genetics, and Parasite Biology and Immunogenetics Research Group, Queen's Medical Centre, University of Nottingham, NG7 2UH, UK.
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29
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Khozoie C, Pleass RJ, Avery SV. The antimalarial drug quinine disrupts Tat2p-mediated tryptophan transport and causes tryptophan starvation. J Biol Chem 2009; 284:17968-74. [PMID: 19416971 PMCID: PMC2709357 DOI: 10.1074/jbc.m109.005843] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2009] [Revised: 04/09/2009] [Indexed: 11/06/2022] Open
Abstract
Quinine is a major drug of choice for the treatment of malaria. However, the primary mode of quinine action is unclear, and its efficacy is marred by adverse reactions among patients. To help address these issues, a genome-wide screen for quinine sensitivity was carried out using the yeast deletion strain collection. Quinine-sensitive mutants identified in the screen included several that were defective for tryptophan biosynthesis (trp strains). This sensitivity was confirmed in independent assays and was suppressible with exogenous Trp, suggesting that quinine caused Trp starvation. Accordingly, quinine was found to inhibit [(3)H]Trp uptake by cells, and the quinine sensitivity of a trp1Delta mutant could be rescued by overexpression of Trp permeases, encoded by TAT1 and TAT2. The site of quinine action was identified specifically as the high affinity Trp/Tyr permease, Tat2p, with which quinine associated in a Trp-suppressible manner. A resultant action also on Tyr levels was reflected by the Tyr-suppressible quinine hypersensitivity of an aro7Delta deletion strain, which is auxotrophic for Tyr (and Phe). The present genome-wide dataset provides an important resource for discovering modes of quinine toxicity. That potential was validated with our demonstration that Trp and Tyr uptake via Tat2p is a major target of cellular quinine toxicity. The results also suggest that dietary tryptophan supplements could help to avert the toxic effects of quinine.
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Affiliation(s)
- Combiz Khozoie
- From the School of Biology, Institute of Genetics, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom
| | - Richard J. Pleass
- From the School of Biology, Institute of Genetics, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom
| | - Simon V. Avery
- From the School of Biology, Institute of Genetics, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom
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Abstract
Platelets might have a crucial role in the pathogenesis of both human and rodent malarias by assisting in the sequestration of infected erythrocytes within the cerebral vasculature. However, recent elegant work by McMorran et al. suggests that they are also involved in innate protection during the early stages of infection. Here, we discuss the implications of their important findings in the context of immunity to malaria.
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Affiliation(s)
- Richard J Pleass
- Institute of Genetics, School of Biology, University of Nottingham, NG7 2UH, UK.
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32
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Ghumra A, Shi J, Mcintosh RS, Rasmussen IB, Braathen R, Johansen FE, Sandlie I, Mongini PK, Areschoug T, Lindahl G, Lewis MJ, Woof JM, Pleass RJ. Structural requirements for the interaction of human IgM and IgA with the human Fcalpha/mu receptor. Eur J Immunol 2009; 39:1147-56. [PMID: 19266484 DOI: 10.1002/eji.200839184] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Here we unravel the structural features of human IgM and IgA that govern their interaction with the human Fcalpha/mu receptor (hFcalpha/muR). Ligand polymerization status was crucial for the interaction, because hFcalpha/muR binding did not occur with monomeric Ab of either class. hFcalpha/muR bound IgM with an affinity in the nanomolar range, whereas the affinity for dimeric IgA (dIgA) was tenfold lower. Panels of mutant IgM and dIgA were used to identify regions critical for hFcalpha/muR binding. IgM binding required contributions from both Cmu3 and Cmu4 Fc domains, whereas for dIgA, an exposed loop in the Calpha3 domain was crucial. This loop, comprising residues Pro440-Phe443, lies at the Fc domain interface and has been implicated in the binding of host receptors FcalphaRI and polymeric Ig receptor (pIgR), as well as IgA-binding proteins produced by certain pathogenic bacteria. Substitutions within the Pro440-Phe443 loop resulted in loss of hFcalpha/muR binding. Furthermore, secretory component (SC, the extracellular portion of pIgR) and bacterial IgA-binding proteins were shown to inhibit the dIgA-hFcalpha/muR interaction. Therefore, we have identified a motif in the IgA-Fc inter-domain region critical for hFcalpha/muR interaction, and highlighted the multi-functional nature of a key site for protein-protein interaction at the IgA Fc domain interface.
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Affiliation(s)
- Ashfaq Ghumra
- Institute of Genetics, Queens Medical Centre, University of Nottingham, Nottingham, UK
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33
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Abstract
Immune complexes (ICs) are believed to play an important role in malaria pathology, and an interesting article by Mibei et al. recently published by Parasite Immunology suggests that IgG4 and IgE are particularly important. However, researchers should be aware of potential pitfalls to current assays aimed at measuring plasma ICs and correlating these to deposition in tissues.
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Affiliation(s)
- R J Pleass
- Institute of Genetics, Queen's Medical Centre, Nottingham, UK.
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34
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Ghumra A, Shi J, Mcintosh RS, Rasmussen IB, Braathen R, Johansen FE, Sandlie I, Mongini PK, Areschoug T, Lindahl G, Lewis MJ, Woof JM, Pleass RJ. Cover Picture: Eur. J. Immunol. 4/09. Eur J Immunol 2009. [DOI: 10.1002/eji.200990017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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35
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Ghumra A, Semblat JP, McIntosh RS, Raza A, Rasmussen IB, Braathen R, Johansen FE, Sandlie I, Mongini PK, Rowe JA, Pleass RJ. Identification of residues in the Cmu4 domain of polymeric IgM essential for interaction with Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1). J Immunol 2008; 181:1988-2000. [PMID: 18641336 DOI: 10.4049/jimmunol.181.3.1988] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The binding of nonspecific human IgM to the surface of infected erythrocytes is important in rosetting, a major virulence factor in the pathogenesis of severe malaria due to Plasmodium falciparum, and IgM binding has also been implicated in placental malaria. Herein we have identified the IgM-binding parasite ligand from a virulent P. falciparum strain as PfEMP1 (TM284var1 variant), and localized the region within this PfEMP1 variant that binds IgM (DBL4beta domain). We have used this parasite IgM-binding protein to investigate the interaction with human IgM. Interaction studies with domain-swapped Abs, IgM mutants, and anti-IgM mAbs showed that PfEMP1 binds to the Fc portion of the human IgM H chain and requires the IgM Cmu4 domain. Polymerization of IgM was shown to be crucial for the interaction because PfEMP1 binding did not occur with mutant monomeric IgM molecules. These results with PfEMP1 protein have physiological relevance because infected erythrocytes from strain TM284 and four other IgM-binding P. falciparum strains showed analogous results to those seen with the DBL4beta domain. Detailed investigation of the PfEMP1 binding site on IgM showed that some of the critical amino acids in the IgM Cmu4 domain are equivalent to those regions of IgG and IgA recognized by Fc-binding proteins from bacteria, suggesting that this region of Ig molecules may be of major functional significance in host-microbe interactions. We have therefore shown that PfEMP1 is an Fc-binding protein of malaria parasites specific for polymeric human IgM, and that it shows functional similarities with Fc-binding proteins from pathogenic bacteria.
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Affiliation(s)
- Ashfaq Ghumra
- Institute of Genetics, Queens Medical Centre, University of Nottingham, Nottingham, England, United Kingdom
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36
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Affiliation(s)
- A Aslam
- School of Pharmacy, Centre for Biomolecular Sciences, University of Nottingham, Nottingham NG7 2RD, UK.
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37
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Pleass RJ, Aboobaker AA, Schmitt AO. Piggybacking schistosome invasion: similarities are only skin deep. Trends Parasitol 2008; 24:153-6. [DOI: 10.1016/j.pt.2008.01.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2007] [Revised: 01/07/2008] [Accepted: 01/09/2008] [Indexed: 12/11/2022]
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38
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Aslam A, Quinn P, McIntosh RS, Shi J, Ghumra A, McKerrow JH, Bunting KA, Dunne DW, Doenhoff MJ, Morrison SL, Zhang K, Pleass RJ. Proteases from Schistosoma mansoni cercariae cleave IgE at solvent exposed interdomain regions. Mol Immunol 2008; 45:567-74. [PMID: 17631966 DOI: 10.1016/j.molimm.2007.05.021] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2007] [Revised: 05/04/2007] [Accepted: 05/08/2007] [Indexed: 11/15/2022]
Abstract
Parasitic infections, including schistosomiasis, are associated with high titres of specific and non-specific IgE antibody, and many reports show an in vitro role for IgE in parasite killing. Despite an active immune response, schistosomes survive for long periods in the human bloodstream, implying that the parasite is able to overcome or evade the IgE response mounted against it. One such mechanism is through cleavage of IgE into non-functional fragments by potent parasite derived enzymes. Using domain swap antibodies, recombinant Fcepsilon, and C-terminally tagged Cepsilon4 domains, we have narrowed down the principal cleavage sites to the Cepsilon2/Cepsilon3 and Cepsilon3/Cepsilon4 interdomain region of the IgE-Fc. Two serine proteases, one chymotrypsin-like and the second trypsin-like, have been proposed to be involved. Inhibition assays using selective inhibitors confirmed that both proteases contribute to Fc cleavage, although the chymotrypsin-like enzyme makes the greater contribution. Protein sequencing of IgE fragments cleaved by highly pure preparations of the chymotrypsin-like enzyme revealed that cleavage also occurred post Lys residues within kappa light chain dimers (LELK/GA). Related sequences are found in myosin, thrombospondin, collagen and actin-related proteins; macromolecules present in the skin and through which cercariae must penetrate to initiate an infection. Chemical knockout experiments using specific inhibitors and chromogenic substrates allowed us to show that the trypsin-like enzyme was responsible for light chain cleavage. The finding that pathogenic proteases can cleave the Fc of IgE may provide a useful biochemical tool for the further analysis of IgE structure. Indeed, the finding may raise new possibilities for treatment of IgE-mediated allergic reactions mediated through Fcepsilon-receptors.
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Affiliation(s)
- Akhmed Aslam
- Institute of Genetics, University of Nottingham, Queen's Medical Centre, Nottingham, UK.
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39
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McIntosh RS, Shi J, Jennings RM, Chappel JC, de Koning-Ward TF, Smith T, Green J, van Egmond M, Leusen JHW, Lazarou M, van de Winkel J, Jones TS, Crabb BS, Holder AA, Pleass RJ. The importance of human FcgammaRI in mediating protection to malaria. PLoS Pathog 2007; 3:e72. [PMID: 17511516 PMCID: PMC1868954 DOI: 10.1371/journal.ppat.0030072] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2007] [Accepted: 04/04/2007] [Indexed: 11/20/2022] Open
Abstract
The success of passive immunization suggests that antibody-based therapies will be effective at controlling malaria. We describe the development of fully human antibodies specific for Plasmodium falciparum by antibody repertoire cloning from phage display libraries generated from immune Gambian adults. Although these novel reagents bind with strong affinity to malaria parasites, it remains unclear if in vitro assays are predictive of functional immunity in humans, due to the lack of suitable animal models permissive for P. falciparum. A potentially useful solution described herein allows the antimalarial efficacy of human antibodies to be determined using rodent malaria parasites transgenic for P. falciparum antigens in mice also transgenic for human Fc-receptors. These human IgG1s cured animals of an otherwise lethal malaria infection, and protection was crucially dependent on human FcγRI. This important finding documents the capacity of FcγRI to mediate potent antimalaria immunity and supports the development of FcγRI-directed therapy for human malaria. Malaria rivals HIV and tuberculosis as the world's most deadly infection killing a child every 30 seconds. Antibodies and their receptors (Fc-receptors) have been shown to be vital for the development of protective immunity, and as such they act as correlates of protection in studies aimed at defining the best antigens to incorporate into current vaccines. Understanding antibody types and Fc-receptors that optimally induce immunity is therefore vital to developing the best vaccines. Surrogate markers of antibody efficacy currently rely on in vitro assays that are laborious and difficult to reproduce. It remains unclear if such in vitro assays are predictive of functional immunity in humans due to the lack of suitable animal models permissive for Plasmodium falciparum. Here, we create a transgenic in vivo mouse model that has significant advantage over the use of new world primates, the only other model for human malaria. We demonstrate that this model defines an Fc-dependent mechanism of parasite destruction that cannot be assessed in current in vitro assays. The model provides both a test for therapeutic antibody efficacy prior to clinical trials in humans and an important tool in malaria vaccine development.
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Affiliation(s)
- Richard S McIntosh
- Institute of Genetics, Queen's Medical Centre, University of Nottingham, United Kingdom
| | - Jianguo Shi
- Institute of Genetics, Queen's Medical Centre, University of Nottingham, United Kingdom
| | - Richard M Jennings
- Division of Parasitology, National Institute for Medical Research, Medical Research Council, London, United Kingdom
| | - Jonathan C Chappel
- Division of Parasitology, National Institute for Medical Research, Medical Research Council, London, United Kingdom
- Medical Research Council Technology, London, United Kingdom
| | | | - Tim Smith
- Institute of Genetics, Queen's Medical Centre, University of Nottingham, United Kingdom
| | - Judith Green
- Division of Parasitology, National Institute for Medical Research, Medical Research Council, London, United Kingdom
| | - Marjolein van Egmond
- Department of Molecular Cell Biology and Immunology, VU Medical Centre, Amsterdam, Netherlands
| | - Jeanette H. W Leusen
- Immunotherapy Laboratory, Department of Immunology, University Medical Centre Utrecht, Utrecht, Netherlands
| | - Maria Lazarou
- Institute of Genetics, Queen's Medical Centre, University of Nottingham, United Kingdom
| | - Jan van de Winkel
- Immunotherapy Laboratory, Department of Immunology, University Medical Centre Utrecht, Utrecht, Netherlands
- Genmab, Utrecht, Netherlands
| | - Tarran S Jones
- Medical Research Council Technology, London, United Kingdom
| | - Brendan S Crabb
- Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
| | - Anthony A Holder
- Division of Parasitology, National Institute for Medical Research, Medical Research Council, London, United Kingdom
- * To whom correspondence should be addressed. E-mail: (AAH); (RJP)
| | - Richard J Pleass
- Institute of Genetics, Queen's Medical Centre, University of Nottingham, United Kingdom
- * To whom correspondence should be addressed. E-mail: (AAH); (RJP)
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40
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Woods RD, Takahashi N, Aslam A, Pleass RJ, Aizawa SI, Sockett RE. Bifunctional nanotube scaffolds for diverse ligands are purified simply from Escherichia coli strains coexpressing two functionalized flagellar genes. Nano Lett 2007; 7:1809-16. [PMID: 17489638 DOI: 10.1021/nl0702968] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
We functionalized Escherichia coli FliC flagellin proteins to form tailored nanotubes binding single types or pairs of ligands, including divalent cations, fluorescent antibodies, or biotin-avidin-linked moieties such as ferritins. The ratio of each tag in bifunctionalized flagella could be toggled extending their sophistication as nanoscaffolds. Tobacco Etch Virus (TEV) protease site-containing FliCs were cleaved by the cognate protease without filament disintegration, potentiating their use as removable nanolithography masks to deposit attached ligands by protease cleavage.
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Affiliation(s)
- Richard D Woods
- Institute of Genetics, School of Biology, University of Nottingham, Queen's Medical Centre, Nottingham NG7 2UH, UK
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41
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Ghumra A, Pleass RJ. Escherichia coli do not express Fc-receptors for human immunoglobulin G (IgG). Mol Immunol 2007; 44:2144-6. [PMID: 17070911 DOI: 10.1016/j.molimm.2006.09.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2006] [Revised: 09/14/2006] [Accepted: 09/18/2006] [Indexed: 10/24/2022]
Abstract
Gram-positive bacterial pathogens express immunoglobulin (Ig) binding proteins that perturb Fc-dependent functions such as the interaction with complement or phagocytic Fc-receptors. The possession of such molecules by gram-negative bacteria, including Escherichia coli (E. coli), has also been documented. In many such studies, the detection of Ig binding has relied on the use of polyclonal antibodies as detecting reagents. These are not ideal since such preparations may be contaminated with E. coli specific IgG, allowing for the potential misinterpretation of specific F(ab')(2) binding as non-specific Fc mediated binding. Here we use mono-specific recombinant antibodies to develop a novel assay for Ig binding non reliant on traditional polyclonal antibodies, allowing us to demonstrate the unequivocal absence of Fc binding proteins from E. coli.
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Affiliation(s)
- Ashfaq Ghumra
- Institute of Genetics, School of Biology, University of Nottingham NG7 2UH, UK
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42
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Pleass RJ, Lang ML, Kerr MA, Woof JM. IgA is a more potent inducer of NADPH oxidase activation and degranulation in blood eosinophils than IgE. Mol Immunol 2007; 44:1401-8. [PMID: 16777227 DOI: 10.1016/j.molimm.2006.05.002] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2006] [Revised: 05/02/2006] [Accepted: 05/02/2006] [Indexed: 11/24/2022]
Abstract
Human eosinophils can mediate both beneficial and detrimental responses in parasitic and allergic diseases. Binding of aggregated immunoglobulin to Fc receptors on eosinophils mediates important defence processes, including generation of activated oxygen species resulting from NADPH oxidase activation, and eosinophil peroxidase release following degranulation. The abilities of a matched set of IgA, IgG and IgE antibodies to elicit such responses in blood-derived eosinophils were compared using a chemiluminescence assay. IgA and IgG, but not IgE, were found to trigger NADPH oxidase activation and degranulation in eosinophils. This non-responsiveness to IgE did not result from receptor blockade by endogenous IgE since no blood-derived IgE was detectable on freshly isolated eosinophils. Moreover, while cross-linking of FcalphaRI by specific mAbs triggered NADPH oxidase activation and degranulation in blood-derived eosinophils, equivalent cross-linking of FcvarepsilonRI or FcvarepsilonRII did not elicit such responses. Therefore IgA is more potent at eliciting activated oxygen species release and degranulation in eosinophils than IgE, suggesting that the importance of IgA in eosinophil activation in immune defence and allergy may have been underestimated.
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Affiliation(s)
- Richard J Pleass
- Division of Pathology and Neuroscience, University of Dundee Medical School, Ninewells Hospital, Dundee DD1 9SY, United Kingdom
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43
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Abstract
Although controversial, schistosomes are believed to cloak themselves in antibody through non-specific interactions with the immunoglobulin (Ig) molecule. The acquisition of host Ig by the schistosome may mask its foreign status and/or interfere with Fc-dependent functions. We report experiments aimed at characterizing the interaction between Ig-Fc and paramyosin, a schistosome Fc-receptor previously reported to bind human IgG. We show that certain Ig classes, in particular murine IgG2b and IgG3, are not only able to bind recombinant paramyosin, but also associate with other parasite proteins. The Fc region of IgG contains four hydrophobic patches, two of which are known to interact with distinct molecules: one in the Cgamma2-Cgamma3 interdomain region bound by protein G, mannose binding lectin (MBL), and the neonatal Fc-receptor (FcRn), and one at the top of the Cgamma2 domain bound by phagocytic FcgammaRs and C1q. We provisionally discounted the involvement of these regions, since IgG binding by paramyosin did not inhibit FcgammaR-mediated NADPH respiratory bursts, and protein G was unable to block IgG binding to paramyosin. Given their apparent low affinity, we postulate hydrogen bonding between reactive residues in a hydrophobic patch at the bottom of the Cgamma3 domain and negatively charged Glu or Asp amino acids in paramyosin.
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Affiliation(s)
- R S McIntosh
- Institute of Genetics, School of Biology, Queen's Medical Centre, University of Nottingham, Nottingham NG7 2RD, UK
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44
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Jackson JA, Pleass RJ, Cable J, Bradley JE, Tinsley RC. Heterogeneous interspecific interactions in a host-parasite system. Int J Parasitol 2006; 36:1341-9. [PMID: 16934815 DOI: 10.1016/j.ijpara.2006.07.003] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2006] [Revised: 07/11/2006] [Accepted: 07/13/2006] [Indexed: 11/27/2022]
Abstract
Macroparasites of vertebrates usually occur in multi-species communities, producing infections whose outcome in individual hosts or host populations may depend on the dynamics of interactions amongst the different component species. Within a single co-infection, competition can occur between conspecific and heterospecific parasite individuals, either directly or via the host's physiological and immune responses. We studied a natural single-host, multi-parasite model infection system (polystomes in the anuran Xenopus laevis victorianus) in which the parasite species show total interspecific competitive exclusion as adults in host individuals. Multi-species infection experiments indicated that competitive outcomes were dependent on infection species composition and strongly influenced by the intraspecific genetic identity of the interacting organisms. Our results also demonstrate the special importance of temporal heterogeneity (the sequence of infection by different species) in competition and co-existence between parasite species and predict that developmental plasticity in inferior competitors, and the induction of species-specific host resistance, will partition the within-host-individual habitat over time. We emphasise that such local (within-host) context-dependent processes are likely to be a fundamental determinant of population dynamics in multi-species parasite assemblages.
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Affiliation(s)
- J A Jackson
- School of Biology, University of Nottingham, Nottingham NG7 2RD, UK.
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45
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Abstract
Abs (antibodies) are complex glycoproteins that play a crucial role in protective immunity to malaria, but their effectiveness in mediating resistance can be enhanced by genetically engineered modifications that improve on nature. These Abs also aid investigation of immune mechanisms operating to control the disease and are valuable tools in developing neutralization assays for vaccine design. This review explores how this might be achieved.
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Affiliation(s)
- Jianguo Shi
- Institute of Genetics, School of Biology, University of Nottingham NG7 2RD, UK
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46
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Abstract
Antibodies are multifunctional glycoproteins that are found in blood and tissue fluids, and can protect against malaria by binding and neutralizing malaria parasites and preparing them for destruction by immune cells. Important technical advances mean that it is now possible to synthesize antibodies against important Plasmodium antigens that could be used for therapeutic purposes. These reagents could be designed to act like a drug and kill parasites directly, or could be used in vaccine strategies to protect individuals from infection. In this article, we discuss the possible therapeutic uses of antibodies in the treatment and prevention of malaria.
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Affiliation(s)
- Richard J Pleass
- Institute of Genetics, School of Biology, University of Nottingham, Nottingham, NG7 2UH, UK.
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Lewis MJ, Pleass RJ, Batten MR, Atkin JD, Woof JM. Structural Requirements for the Interaction of Human IgA with the Human Polymeric Ig Receptor. J Immunol 2005; 175:6694-701. [PMID: 16272325 DOI: 10.4049/jimmunol.175.10.6694] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Transport of polymeric IgA onto mucosal surfaces to become secretory IgA is mediated by the polymeric Ig receptor (pIgR). To study the interaction of human dimeric IgA (dIgA) (the predominant form of IgA polymer) with the human pIgR (hpIgR), we generated recombinant wild-type dIgA1 and dIgA2m(1) and various mutant dIgA1 and analyzed their interaction with a recombinant human secretory component and membrane-expressed hpIgR. We found that wild-type dIgA1 and dIgA2m(1) bound to recombinant human secretory component with similar affinity and were transcytosed by the hpIgR to the same extent. Mutation of the IgA Calpha2 domain residue Cys311 to Ser reduced binding to hpIgR, possibly through disruption of noncovalent interactions between the Calpha2 domain and domain 5 of the receptor. Within the Calpha3 domain of IgA1, we found that combined mutation of residues Phe411, Val413, and Thr414, which lie close to residues previously implicated in hpIgR binding, abolished interaction with the receptor. Mutation of residue Lys377, located very close to this same region, perturbed receptor interaction. In addition, 4 aa (Pro440-Phe443), which lie on a loop at the domain interface and form part of the binding site for human FcalphaRI, appear to contribute to hpIgR binding. Lastly, use of a monomeric IgA1 mutant lacking the tailpiece revealed that the tailpiece does not occlude hpIgR-binding residues in IgA1 monomers. This directed mutagenesis approach has thus identified motifs lying principally across the upper surface of the Calpha3 domain (i.e., that closest to Calpha2) critical for human pIgR binding and transcytosis.
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Affiliation(s)
- Melanie J Lewis
- Division of Pathology and Neurosciences, University of Dundee Medical School, Ninewells Hospital, Dundee, United Kingdom
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48
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Morton HC, Pleass RJ, Storset AK, Brandtzaeg P, Woof JM. Cloning and characterization of equine CD89 and identification of the CD89 gene in chimpanzees and rhesus macaques. Immunology 2005; 115:74-84. [PMID: 15819699 PMCID: PMC1782135 DOI: 10.1111/j.1365-2567.2005.02129.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Immunoglobulin A (IgA) is the major antibody class present in external secretions of mammals. At the vulnerable mucosal surfaces, IgA provides a crucial first-line defence by neutralizing pathogens. Primates also have a substantial level of IgA in serum and although not well understood, the biological role of this IgA depends, at least partly, on its ability to interact with specific receptors (FcalphaRs) on the surface of leucocytes. The human FcalphaR, CD89, was the first IgA Fc receptor to be identified and binding of IgA-coated particles to CD89 triggers numerous cellular effector functions, including phagocytosis, antibody-dependent cellular cytotoxicity, and release of inflammatory mediators, all of which may play an important role in both systemic and mucosal immunity. For many years humans were the only species known to express CD89, however, it has recently been cloned from cows and rats. Here, we describe the identification of the CD89 gene in three additional species: horses, chimpanzees, and Rhesus macaques. Equine CD89 was identified at the cDNA level, whereas the chimpanzee and Rhesus macaque genes were identified from the available draft genomic sequence. Interestingly, when compared with humans and other primates, horses, cows and rats have a relatively low concentration of serum IgA, so the role of CD89 in these species is of particular interest. The identification and characterization of CD89 in different species will contribute to a greater understanding of the biological role of IgA and CD89 in mucosal and systemic immunity throughout evolution.
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Affiliation(s)
- H Craig Morton
- Laboratory for Immunohistochemistry and Immunopathology (LIIPAT), Institute of Pathology, Rikshospitalet, University Hospital, Oslo, Norway.
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49
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Abstract
Recently, we identified a bovine IgA Fc receptor (bFc alpha R), which shows high homology to the human myeloid Fc alpha R, CD89. IgA binding has previously been shown to depend on several specific residues located in the B-C and F-G loops of the membrane-distal extracellular domain 1 of CD89. To compare the ligand binding properties of these two Fc alpha Rs, we have mapped the IgA binding site of bFc alpha R. We show that, in common with CD89, Tyr-35 in the B-C loop is essential for IgA binding. However, in contrast to earlier observations on CD89, mutation of residues in the F-G loop did not significantly inhibit IgA binding.
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Affiliation(s)
- H Craig Morton
- Laboratory for Immunohistochemistry and Immunopathology, Institute of Pathology, University of Oslo, Rikshospitalet, N-0027 Oslo, Norway.
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50
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Morton HC, Pleass RJ, Storset AK, Dissen E, Williams JL, Brandtzaeg P, Woof JM. Cloning and characterization of an immunoglobulin A Fc receptor from cattle. Immunology 2004; 111:204-11. [PMID: 15027906 PMCID: PMC1782410 DOI: 10.1111/j.0019-2805.2003.01808.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2003] [Revised: 11/26/2003] [Accepted: 11/27/2003] [Indexed: 11/29/2022] Open
Abstract
Here, we describe the cloning, sequencing and characterization of an immunoglobulin A (IgA) Fc receptor from cattle (bFcalphaR). By screening a translated EST database with the protein sequence of the human IgA Fc receptor (CD89) we identified a putative bovine homologue. Subsequent polymerase chain reaction (PCR) amplification confirmed that the identified full-length cDNA was expressed in bovine cells. COS-1 cells transfected with a plasmid containing the cloned cDNA bound to beads coated with either bovine or human IgA, but not to beads coated with bovine IgG2 or human IgG. The bFcalphaR cDNA is 873 nucleotides long and is predicted to encode a 269 amino-acid transmembrane glycoprotein composed of two immunoglobulin-like extracellular domains, a transmembrane region and a short cytoplasmic tail devoid of known signalling motifs. Genetically, bFcalphaR is more closely related to CD89, bFcgamma2R, NKp46, and the KIR and LILR gene families than to other FcRs. Moreover, the bFcalphaR gene maps to the bovine leucocyte receptor complex on chromosome 18. Identification of the bFcalphaR will aid in the understanding of IgA-FcalphaR interactions, and may facilitate the isolation of FcalphaR from other species.
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Affiliation(s)
- H Craig Morton
- Laboratory of Immunohistochemistry and Immunopathology (LIIPAT), Institute of Pathology, University of Oslo, Rikshospitalet, Oslo, Norway.
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