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Molecular and structural basis for Lewis glycan recognition by a cancer-targeting antibody. Biochem J 2021; 477:3219-3235. [PMID: 32789497 DOI: 10.1042/bcj20200454] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 08/11/2020] [Accepted: 08/13/2020] [Indexed: 01/11/2023]
Abstract
Immunotherapy has been successful in treating many tumour types. The development of additional tumour-antigen binding monoclonal antibodies (mAbs) will help expand the range of immunotherapeutic targets. Lewis histo-blood group and related glycans are overexpressed on many carcinomas, including those of the colon, lung, breast, prostate and ovary, and can therefore be selectively targeted by mAbs. Here we examine the molecular and structural basis for recognition of extended Lea and Lex containing glycans by a chimeric mAb. Both the murine (FG88.2) IgG3 and a chimeric (ch88.2) IgG1 mAb variants showed reactivity to colorectal cancer cells leading to significantly reduced cell viability. We determined the X-ray structure of the unliganded ch88.2 fragment antigen-binding (Fab) containing two Fabs in the unit cell. A combination of molecular docking, glycan grafting and molecular dynamics simulations predicts two distinct subsites for recognition of Lea and Lex trisaccharides. While light chain residues were exclusively used for Lea binding, recognition of Lex involved both light and heavy chain residues. An extended groove is predicted to accommodate the Lea-Lex hexasaccharide with adjoining subsites for each trisaccharide. The molecular and structural details of the ch88.2 mAb presented here provide insight into its cross-reactivity for various Lea and Lex containing glycans. Furthermore, the predicted interactions with extended epitopes likely explains the selectivity of this antibody for targeting Lewis-positive tumours.
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Bloise N, Okkeh M, Restivo E, Della Pina C, Visai L. Targeting the "Sweet Side" of Tumor with Glycan-Binding Molecules Conjugated-Nanoparticles: Implications in Cancer Therapy and Diagnosis. NANOMATERIALS (BASEL, SWITZERLAND) 2021; 11:289. [PMID: 33499388 PMCID: PMC7911724 DOI: 10.3390/nano11020289] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 01/17/2021] [Accepted: 01/20/2021] [Indexed: 02/07/2023]
Abstract
Nanotechnology is in the spotlight of therapeutic innovation, with numerous advantages for tumor visualization and eradication. The end goal of the therapeutic use of nanoparticles, however, remains distant due to the limitations of nanoparticles to target cancer tissue. The functionalization of nanosystem surfaces with biological ligands is a major strategy for directing the actions of nanomaterials specifically to tumor cells. Cancer formation and metastasis are accompanied by profound alterations in protein glycosylation. Hence, the detection and targeting of aberrant glycans are of great value in cancer diagnosis and therapy. In this review, we provide a brief update on recent progress targeting aberrant glycosylation by functionalizing nanoparticles with glycan-binding molecules (with a special focus on lectins and anti-glycan antibodies) to improve the efficacy of nanoparticles in cancer targeting, diagnosis, and therapy and outline the challenges and limitations in implementing this approach. We envision that the combination of nanotechnological strategies and cancer-associated glycan targeting could remodel the field of cancer diagnosis and therapy, including immunotherapy.
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Affiliation(s)
- Nora Bloise
- Department of Molecular Medicine, Center for Health Technologies (CHT), INSTM UdR of Pavia, University of Pavia, Viale Taramelli, 3/B-27100 Pavia, Italy; (M.O.); (E.R.); (L.V.)
- Medicina Clinica-Specialistica, UOR5 Laboratorio Di Nanotecnologie, ICS Maugeri, IRCCS, Pavia, Via Boezio, 28-27100 Pavia, Italy
| | - Mohammad Okkeh
- Department of Molecular Medicine, Center for Health Technologies (CHT), INSTM UdR of Pavia, University of Pavia, Viale Taramelli, 3/B-27100 Pavia, Italy; (M.O.); (E.R.); (L.V.)
- Medicina Clinica-Specialistica, UOR5 Laboratorio Di Nanotecnologie, ICS Maugeri, IRCCS, Pavia, Via Boezio, 28-27100 Pavia, Italy
| | - Elisa Restivo
- Department of Molecular Medicine, Center for Health Technologies (CHT), INSTM UdR of Pavia, University of Pavia, Viale Taramelli, 3/B-27100 Pavia, Italy; (M.O.); (E.R.); (L.V.)
- Medicina Clinica-Specialistica, UOR5 Laboratorio Di Nanotecnologie, ICS Maugeri, IRCCS, Pavia, Via Boezio, 28-27100 Pavia, Italy
| | - Cristina Della Pina
- Dipartimento di Chimica, Università Degli Studi di Milano e CNR-ISTM, Via C. Golgi, 19, 20133 Milan, Italy;
| | - Livia Visai
- Department of Molecular Medicine, Center for Health Technologies (CHT), INSTM UdR of Pavia, University of Pavia, Viale Taramelli, 3/B-27100 Pavia, Italy; (M.O.); (E.R.); (L.V.)
- Medicina Clinica-Specialistica, UOR5 Laboratorio Di Nanotecnologie, ICS Maugeri, IRCCS, Pavia, Via Boezio, 28-27100 Pavia, Italy
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Thomas D, Rathinavel AK, Radhakrishnan P. Altered glycosylation in cancer: A promising target for biomarkers and therapeutics. Biochim Biophys Acta Rev Cancer 2020; 1875:188464. [PMID: 33157161 DOI: 10.1016/j.bbcan.2020.188464] [Citation(s) in RCA: 126] [Impact Index Per Article: 31.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Revised: 10/08/2020] [Accepted: 10/28/2020] [Indexed: 12/13/2022]
Abstract
Glycosylation is a well-regulated cell and microenvironment specific post-translational modification. Several glycosyltransferases and glycosidases orchestrate the addition of defined glycan structures on the proteins and lipids. Recent advances and systemic approaches in glycomics have significantly contributed to a better understanding of instrumental roles of glycans in health and diseases. Emerging research evidence recognized aberrantly glycosylated proteins as the modulators of the malignant phenotype of cancer cells. The Cancer Genome Atlas has identified alterations in the expressions of glycosylation-specific genes that are correlated with cancer progression. However, the mechanistic basis remains poorly explored. Recent researches have shown that specific changes in the glycan structures are associated with 'stemness' and epithelial-to-mesenchymal transition of cancer cells. Moreover, epigenetic changes in the glycosylation pattern make the tumor cells capable of escaping immunosurveillance mechanisms. The deciphering roles of glycans in cancer emphasize that glycans can serve as a source for the development of novel clinical biomarkers. The ability of glycans in intervening various stages of tumor progression and the biosynthetic pathways involved in glycan structures constitute a promising target for cancer therapy. Advances in the knowledge of innovative strategies for identifying the mechanisms of glycan-binding proteins are hoped to hold great potential in cancer therapy. This review discusses the fundamental role of glycans in regulating tumorigenesis and tumor progression and provides insights into the influence of glycans in the current tactics of targeted therapies in the clinical setting.
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Affiliation(s)
- Divya Thomas
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE 68198, USA; Fred & Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Ashok Kumar Rathinavel
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE 68198, USA; Fred & Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Prakash Radhakrishnan
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE 68198, USA; Fred & Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, NE 68198, USA; Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198, USA; Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198, USA; Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, NE 68198, USA.
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4
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Antibody recognition of aberrant glycosylation on the surface of cancer cells. Curr Opin Struct Biol 2016; 44:1-8. [PMID: 27821276 DOI: 10.1016/j.sbi.2016.10.009] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 09/28/2016] [Accepted: 10/13/2016] [Indexed: 11/23/2022]
Abstract
Carbohydrate-binding antibodies and carbohydrate-based vaccines are being actively pursued as targeted immunotherapies for a broad range of cancers. Recognition of tumor-associated carbohydrates (glycans) by antibodies is predominantly towards terminal epitopes on glycoproteins and glycolipids on the surface of cancer cells. Crystallography along with complementary experimental and computational methods have been extensively used to dissect antibody recognition of glycan epitopes commonly found in cancer. We provide an overview of the structural biology of antibody recognition of tumor-associated glycans and propose potential rearrangements of these targets in the membrane that could dictate the complex biological activities of these antibodies against cancer cells.
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Burvenich IJG, Farrugia W, Lee FT, Catimel B, Liu Z, Makris D, Cao D, O'Keefe GJ, Brechbiel MW, King D, Spirkoska V, Allan LC, Ramsland PA, Scott AM. Cross-species analysis of Fc engineered anti-Lewis-Y human IgG1 variants in human neonatal receptor transgenic mice reveal importance of S254 and Y436 in binding human neonatal Fc receptor. MAbs 2016; 8:775-86. [PMID: 27030023 DOI: 10.1080/19420862.2016.1156285] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
IgG has a long half-life through engagement of its Fc region with the neonatal Fc receptor (FcRn). The FcRn binding site on IgG1 has been shown to contain I253 and H310 in the CH2 domain and H435 in the CH3 domain. Altering the half-life of IgG has been pursued with the aim to prolong or reduce the half-life of therapeutic IgGs. More recent studies have shown that IgGs bind differently to mouse and human FcRn. In this study we characterize a set of hu3S193 IgG1 variants with mutations in the FcRn binding site. A double mutation in the binding site is necessary to abrogate binding to murine FcRn, whereas a single mutation in the FcRn binding site is sufficient to no longer detect binding to human FcRn and create hu3S193 IgG1 variants with a half-life similar to previously studied hu3S193 F(ab')2 (t1/2β, I253A, 12.23 h; H310A, 12.94; H435A, 12.57; F(ab')2, 12.6 h). Alanine substitutions in S254 in the CH2 domain and Y436 in the CH3 domain showed reduced binding in vitro to human FcRn and reduced elimination half-lives in huFcRn transgenic mice (t1/2β, S254A, 37.43 h; Y436A, 39.53 h; wild-type, 83.15 h). These variants had minimal effect on half-life in BALB/c nu/nu mice (t1/2β, S254A, 119.9 h; Y436A, 162.1 h; wild-type, 163.1 h). These results provide insight into the interaction of human Fc by human FcRn, and are important for antibody-based therapeutics with optimal pharmacokinetics for payload strategies used in the clinic.
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Affiliation(s)
- Ingrid J G Burvenich
- a Tumour Targeting Laboratory, Ludwig Institute for Cancer Research and Olivia Newton-John Cancer Research Institute , Melbourne , VIC , Australia.,b School of Cancer Medicine, La Trobe University , Melbourne , VIC , Australia
| | - William Farrugia
- c Centre for Biomedical Research, Burnet Institute , Melbourne , VIC , Australia
| | - Fook T Lee
- a Tumour Targeting Laboratory, Ludwig Institute for Cancer Research and Olivia Newton-John Cancer Research Institute , Melbourne , VIC , Australia
| | - Bruno Catimel
- a Tumour Targeting Laboratory, Ludwig Institute for Cancer Research and Olivia Newton-John Cancer Research Institute , Melbourne , VIC , Australia
| | - Zhanqi Liu
- a Tumour Targeting Laboratory, Ludwig Institute for Cancer Research and Olivia Newton-John Cancer Research Institute , Melbourne , VIC , Australia
| | - Dahna Makris
- a Tumour Targeting Laboratory, Ludwig Institute for Cancer Research and Olivia Newton-John Cancer Research Institute , Melbourne , VIC , Australia
| | - Diana Cao
- a Tumour Targeting Laboratory, Ludwig Institute for Cancer Research and Olivia Newton-John Cancer Research Institute , Melbourne , VIC , Australia
| | - Graeme J O'Keefe
- b School of Cancer Medicine, La Trobe University , Melbourne , VIC , Australia.,d Department of Molecular Imaging and Therapy, Austin Health , Melbourne , Australia
| | - Martin W Brechbiel
- e Radioimmune Inorganic Chemistry Section, Radiation Oncology Branch, Center for Cancer Research, National Cancer Institute , Bethesda , MD , USA
| | - Dylan King
- a Tumour Targeting Laboratory, Ludwig Institute for Cancer Research and Olivia Newton-John Cancer Research Institute , Melbourne , VIC , Australia
| | - Violeta Spirkoska
- a Tumour Targeting Laboratory, Ludwig Institute for Cancer Research and Olivia Newton-John Cancer Research Institute , Melbourne , VIC , Australia
| | - Laura C Allan
- a Tumour Targeting Laboratory, Ludwig Institute for Cancer Research and Olivia Newton-John Cancer Research Institute , Melbourne , VIC , Australia
| | - Paul A Ramsland
- c Centre for Biomedical Research, Burnet Institute , Melbourne , VIC , Australia.,f School of Science, RMIT University , Bundoora , VIC , Australia.,g Department of Immunology , Monash University , Melbourne , VIC , Australia.,h Department of Surgery Austin Health , University of Melbourne , Heidelberg , VIC , Australia
| | - Andrew M Scott
- a Tumour Targeting Laboratory, Ludwig Institute for Cancer Research and Olivia Newton-John Cancer Research Institute , Melbourne , VIC , Australia.,b School of Cancer Medicine, La Trobe University , Melbourne , VIC , Australia.,d Department of Molecular Imaging and Therapy, Austin Health , Melbourne , Australia.,i Faculty of Medicine, University of Melbourne , Melbourne , VIC , Australia
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Dingjan T, Spendlove I, Durrant LG, Scott AM, Yuriev E, Ramsland PA. Structural biology of antibody recognition of carbohydrate epitopes and potential uses for targeted cancer immunotherapies. Mol Immunol 2015; 67:75-88. [PMID: 25757815 DOI: 10.1016/j.molimm.2015.02.028] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Revised: 02/16/2015] [Accepted: 02/19/2015] [Indexed: 11/18/2022]
Abstract
Monoclonal antibodies represent the most successful class of biopharmaceuticals for the treatment of cancer. Mechanisms of action of therapeutic antibodies are very diverse and reflect their ability to engage in antibody-dependent effector mechanisms, internalize to deliver cytotoxic payloads, and display direct effects on cells by lysis or by modulating the biological pathways of their target antigens. Importantly, one of the universal changes in cancer is glycosylation and carbohydrate-binding antibodies can be produced to selectively recognize tumor cells over normal tissues. A promising group of cell surface antibody targets consists of carbohydrates presented as glycolipids or glycoproteins. In this review, we outline the basic principles of antibody-based targeting of carbohydrate antigens in cancer. We also present a detailed structural view of antibody recognition and the conformational properties of a series of related tissue-blood group (Lewis) carbohydrates that are being pursued as potential targets of cancer immunotherapy.
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Affiliation(s)
- Tamir Dingjan
- Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC 3052, Australia
| | - Ian Spendlove
- Academic Department of Clinical Oncology, Division of Cancer and Stem cells, University of Nottingham, City Hospital, Nottingham NG5 1PB, United Kingdom
| | - Lindy G Durrant
- Academic Department of Clinical Oncology, Division of Cancer and Stem cells, University of Nottingham, City Hospital, Nottingham NG5 1PB, United Kingdom
| | - Andrew M Scott
- Tumour Targeting Laboratory, Olivia Newton-John Cancer Research Institute, Melbourne, VIC, Australia; Faculty of Medicine, University of Melbourne, Melbourne, VIC, Australia; School of Cancer Medicine, La Trobe University, Melbourne, VIC, Australia
| | - Elizabeth Yuriev
- Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC 3052, Australia.
| | - Paul A Ramsland
- Centre for Biomedical Research, Burnet Institute, Melbourne, VIC 3004, Australia; Department of Immunology, Monash University, Alfred Medical Research and Education Precinct, Melbourne, VIC 3004, Australia; Department of Surgery Austin Health, University of Melbourne, Heidelberg, VIC 3084, Australia; School of Biomedical Sciences, CHIRI Biosciences, Curtin University, Perth, WA 6845, Australia.
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7
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Nasir W, Frank M, Koppisetty CAK, Larson G, Nyholm PG. Lewis histo-blood group α1,3/α1,4 fucose residues may both mediate binding to GII.4 noroviruses. Glycobiology 2012; 22:1163-72. [PMID: 22589081 DOI: 10.1093/glycob/cws084] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Human noroviruses cause recurrent epidemics of gastroenteritis known to be dominated by the clinically important GII.4 genotype which recognizes human Secretor gene-dependent ABH histo-blood group antigens (HBGAs) as attachment factors. There is increasing evidence that GII.4 noroviruses have undergone evolutionary changes to recognize Lewis antigens and non-Secretor saliva. In this study, we have investigated the possibilities of the Lewis α1,3/α1,4 fucoses as mediators of binding of GII.4 noroviruses to Lewis antigens. The study was carried out using molecular dynamics simulations of Lewis type-1 and type-2 chain HBGAs in complex with VA387 P domain dimers in explicit water. Based on the computer simulations, we suggest the possibility of two receptor binding modes for Lewis HBGAs: the "Secretor pose" with the Secretor Fucα1,2 in the binding site and the "Lewis pose" with the Lewis Fucα1,3/α1,4 residues in the binding site. This was further supported by an extensive GlyVicinity analysis of the Protein Data Bank with respect to the occurrence of the Lewis and Secretor poses in complexes of Lewis antigens with lectins and antibodies as well as GII norovirus strains. The Lewis pose can also explain the interactions of GII.4 norovirus strains with Le(x) and SLe(x) structures. Moreover, the present model suggests binding of complex branched polysaccharides, with the Lewis antigens at the nonreducing end, to P domain dimers of GII.4 strains. Our results are relevant for understanding the evolution of norovirus binding specificities and for in silico design of future antiviral therapeutics.
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Affiliation(s)
- Waqas Nasir
- Department of Clinical Chemistry and Transfusion Medicine, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
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8
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Feil SC, Lawrence S, Mulhern TD, Holien JK, Hotze EM, Farrand S, Tweten RK, Parker MW. Structure of the lectin regulatory domain of the cholesterol-dependent cytolysin lectinolysin reveals the basis for its lewis antigen specificity. Structure 2012; 20:248-58. [PMID: 22325774 PMCID: PMC3682648 DOI: 10.1016/j.str.2011.11.017] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2011] [Revised: 10/25/2011] [Accepted: 11/03/2011] [Indexed: 10/14/2022]
Abstract
The cholesterol-dependent cytolysins (CDCs) punch holes in target cell membranes through a highly regulated process. Streptococcus mitis lectinolysin (LLY) exhibits another layer of regulation with a lectin domain that enhances the pore-forming activity of the toxin. We have determined the crystal structures of the lectin domain by itself and in complex with various glycans that reveal the molecular basis for the Lewis antigen specificity of LLY. A small-angle X-ray scattering study of intact LLY reveals the molecule is flat and elongated with the lectin domain oriented so that the Lewis antigen-binding site is exposed. We suggest that the lectin domain enhances the pore-forming activity of LLY by concentrating toxin molecules at fucose-rich sites on membranes, thus promoting the formation of prepore oligomers on the surface of susceptible cells.
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Affiliation(s)
- Susanne C. Feil
- Biota Structural Biology Laboratory, St. Vincent’s Institute of Medical Research, Fitzroy, Victoria 3065, Australia
| | - Sara Lawrence
- Biota Structural Biology Laboratory, St. Vincent’s Institute of Medical Research, Fitzroy, Victoria 3065, Australia
| | - Terrence D. Mulhern
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Jessica K. Holien
- Biota Structural Biology Laboratory, St. Vincent’s Institute of Medical Research, Fitzroy, Victoria 3065, Australia
| | - Eileen M. Hotze
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Stephen Farrand
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Rodney K. Tweten
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Michael W. Parker
- Biota Structural Biology Laboratory, St. Vincent’s Institute of Medical Research, Fitzroy, Victoria 3065, Australia
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria 3010, Australia
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Ramsland PA, Farrugia W, Bradford TM, Tan Sardjono C, Esparon S, Trist HM, Powell MS, Szee Tan P, Cendron AC, Wines BD, Scott AM, Hogarth PM. Structural basis for Fc gammaRIIa recognition of human IgG and formation of inflammatory signaling complexes. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2011; 187:3208-17. [PMID: 21856937 PMCID: PMC3282893 DOI: 10.4049/jimmunol.1101467] [Citation(s) in RCA: 116] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The interaction of Abs with their specific FcRs is of primary importance in host immune effector systems involved in infection and inflammation, and are the target for immune evasion by pathogens. FcγRIIa is a unique and the most widespread activating FcR in humans that through avid binding of immune complexes potently triggers inflammation. Polymorphisms of FcγRIIa (high responder/low responder [HR/LR]) are linked to susceptibility to infections, autoimmune diseases, and the efficacy of therapeutic Abs. In this article, we define the three-dimensional structure of the complex between the HR (arginine, R134) allele of FcγRIIa (FcγRIIa-HR) and the Fc region of a humanized IgG1 Ab, hu3S193. The structure suggests how the HR/LR polymorphism may influence FcγRIIa interactions with different IgG subclasses and glycoforms. In addition, mutagenesis defined the basis of the epitopes detected by FcR blocking mAbs specific for FcγRIIa (IV.3), FcγRIIb (X63-21), and a pan FcγRII Ab (8.7). The epitopes detected by these Abs are distinct, but all overlap with residues defined by crystallography to contact IgG. Finally, crystal structures of LR (histidine, H134) allele of FcγRIIa and FcγRIIa-HR reveal two distinct receptor dimers that may represent quaternary states on the cell surface. A model is presented whereby a dimer of FcγRIIa-HR binds Ag-Ab complexes in an arrangement that possibly occurs on the cell membrane as part of a larger signaling assembly.
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Affiliation(s)
- Paul A. Ramsland
- Centre for Immunology, Burnet Institute, Melbourne, Victoria 3004, Australia,Department of Surgery, Austin Hospital, University of Melbourne, Heidelberg, Victoria 3084, Australia,Department of Immunology, Monash University, Melbourne, Victoria 3004, Australia
| | - William Farrugia
- Centre for Immunology, Burnet Institute, Melbourne, Victoria 3004, Australia
| | - Tessa M. Bradford
- Centre for Immunology, Burnet Institute, Melbourne, Victoria 3004, Australia
| | | | - Sandra Esparon
- Centre for Immunology, Burnet Institute, Melbourne, Victoria 3004, Australia
| | - Halina M. Trist
- Centre for Immunology, Burnet Institute, Melbourne, Victoria 3004, Australia
| | - Maree S. Powell
- Centre for Immunology, Burnet Institute, Melbourne, Victoria 3004, Australia,Department of Immunology, Monash University, Melbourne, Victoria 3004, Australia,Department of Pathology, University of Melbourne, Parkville, Victoria 3056, Australia
| | - Peck Szee Tan
- Centre for Immunology, Burnet Institute, Melbourne, Victoria 3004, Australia
| | - Angela C. Cendron
- Centre for Immunology, Burnet Institute, Melbourne, Victoria 3004, Australia
| | - Bruce D. Wines
- Centre for Immunology, Burnet Institute, Melbourne, Victoria 3004, Australia,Department of Immunology, Monash University, Melbourne, Victoria 3004, Australia,Department of Pathology, University of Melbourne, Parkville, Victoria 3056, Australia
| | - Andrew M. Scott
- Tumour Targeting Program, Ludwig Institute for Cancer Research, Austin Health, Heidelberg, Victoria 3084, Australia
| | - P. Mark Hogarth
- Centre for Immunology, Burnet Institute, Melbourne, Victoria 3004, Australia,Department of Immunology, Monash University, Melbourne, Victoria 3004, Australia,Department of Pathology, University of Melbourne, Parkville, Victoria 3056, Australia
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10
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Agostino M, Yuriev E, Ramsland PA. A computational approach for exploring carbohydrate recognition by lectins in innate immunity. Front Immunol 2011; 2:23. [PMID: 22566813 PMCID: PMC3342079 DOI: 10.3389/fimmu.2011.00023] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2011] [Accepted: 06/14/2011] [Indexed: 11/13/2022] Open
Abstract
Recognition of pathogen-associated carbohydrates by a broad range of carbohydrate-binding proteins is central to both adaptive and innate immunity. A large functionally diverse group of mammalian carbohydrate-binding proteins are lectins, which often display calcium-dependent carbohydrate interactions mediated by one or more carbohydrate recognition domains. We report here the application of molecular docking and site mapping to study carbohydrate recognition by several lectins involved in innate immunity or in modulating adaptive immune responses. It was found that molecular docking programs can identify the correct carbohydrate-binding mode, but often have difficulty in ranking it as the best pose. This is largely attributed to the broad and shallow nature of lectin binding sites, and the high flexibility of carbohydrates. Site mapping is very effective at identifying lectin residues involved in carbohydrate recognition, especially with cases that were found to be particularly difficult to characterize via molecular docking. This study highlights the need for alternative strategies to examine carbohydrate–lectin interactions, and specifically demonstrates the potential for mapping methods to extract additional and relevant information from the ensembles of binding poses generated by molecular docking.
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Affiliation(s)
- Mark Agostino
- Medicinal Chemistry and Drug Action, Monash Institute of Pharmaceutical Sciences, Monash University Parkville, VIC, Australia
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11
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Li M, Gustchina A, Glesner J, Wünschmann S, Vailes LD, Chapman MD, Pomés A, Wlodawer A. Carbohydrates contribute to the interactions between cockroach allergen Bla g 2 and a monoclonal antibody. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2011; 186:333-40. [PMID: 21123808 PMCID: PMC3099132 DOI: 10.4049/jimmunol.1002318] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The crystal structure of a murine mAb, 4C3, that binds to the C-terminal lobe of the cockroach allergen Bla g 2 has been solved at 1.8 Å resolution. Binding of 4C3 involves different types of molecular interactions with its epitope compared with those with the mAb 7C11, which binds to the N-terminal lobe of Bla g 2. We found that the 4C3 surface epitope on Bla g 2 includes a carbohydrate moiety attached to Asn(268) and that a large number of Ag-Ab contacts are mediated by water molecules and ions, most likely zinc. Ab binding experiments conducted with an enzymatically deglycosylated Bla g 2 and a N268Q mutant showed that the carbohydrate contributes, without being essential, to the Bla g 2-4C3 mAb interaction. Inhibition of IgE Ab binding by the mAb 4C3 shows a correlation of the structurally defined epitope with reactivity with human IgE. Site-directed mutagenesis of the 4C3 mAb epitope confirmed that the amino acids Lys(251), Glu(233), and Ile(199) are important for the recognition of Bla g 2 by the 4C3 mAb. The results show the relevance of x-ray crystallographic studies of allergen-Ab complexes to identify conformational epitopes that define the antigenic surface of Bla g 2.
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Affiliation(s)
- Mi Li
- Macromolecular Crystallography Laboratory, National Cancer Institute, Frederick, MD 21702, USA
- Basic Research Program, SAIC-Frederick, Frederick, MD 21702, USA
| | - Alla Gustchina
- Macromolecular Crystallography Laboratory, National Cancer Institute, Frederick, MD 21702, USA
| | - Jill Glesner
- INDOOR Biotechnologies, Inc., 1216 Harris Street, Charlottesville, VA 22903, USA
| | - Sabina Wünschmann
- INDOOR Biotechnologies, Inc., 1216 Harris Street, Charlottesville, VA 22903, USA
| | - Lisa D. Vailes
- INDOOR Biotechnologies, Inc., 1216 Harris Street, Charlottesville, VA 22903, USA
| | - Martin D. Chapman
- INDOOR Biotechnologies, Inc., 1216 Harris Street, Charlottesville, VA 22903, USA
| | - Anna Pomés
- INDOOR Biotechnologies, Inc., 1216 Harris Street, Charlottesville, VA 22903, USA
| | - Alexander Wlodawer
- Macromolecular Crystallography Laboratory, National Cancer Institute, Frederick, MD 21702, USA
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Hutchinson AT, Ramsland PA, Jones DR, Agostino M, Lund ME, Jennings CV, Bockhorni V, Yuriev E, Edmundson AB, Raison RL. Free Ig Light Chains Interact with Sphingomyelin and Are Found on the Surface of Myeloma Plasma Cells in an Aggregated Form. THE JOURNAL OF IMMUNOLOGY 2010; 185:4179-88. [DOI: 10.4049/jimmunol.1001956] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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