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Katsara M, Yuriev E, Ramsland PA, Deraos G, Tselios T, Matsoukas J, Apostolopoulos V. Mannosylation of mutated MBP83-99 peptides diverts immune responses from Th1 to Th2. Mol Immunol 2008; 45:3661-70. [PMID: 18541301 DOI: 10.1016/j.molimm.2008.04.024] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2008] [Revised: 04/22/2008] [Accepted: 04/23/2008] [Indexed: 10/22/2022]
Abstract
Multiple sclerosis (MS) is an autoimmune demyelinating disease mediated primarily by CD4+ T cells. The design of peptide mutants of disease-associated myelin epitopes to alter immune responses offers a promising avenue for the treatment of MS. We designed and synthesized a number of peptide analogs by mutating the principal TCR contact residue based on MBP83-99 epitope and these peptides were conjugated to reduced mannan. Immune responses were diverted from Th1 to Th2 in SJL/J mice and generated antibodies which did not cross-react with native MBP protein. Peptide [Y91]MBP83-99 gave the best cytokine and antibody profile and constitutes a promising candidate peptide for immunotherapy of MS. Structural alignment of existing crystal structures revealed the peptide binding motif of I-As. Molecular modeling was used to identify H-bonding and van der Waals interactions between peptides and MHC (I-A(s)).
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Affiliation(s)
- Maria Katsara
- Immunology and Vaccine Laboratory, Burnet Institute (Austin campus), VIC, Australia
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52
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Mantzourani ED, Blokar K, Tselios TV, Matsoukas JM, Platts JA, Mavromoustakos TM, Grdadolnik SG. A combined NMR and molecular dynamics simulation study to determine the conformational properties of agonists and antagonists against experimental autoimmune encephalomyelitis. Bioorg Med Chem 2008; 16:2171-82. [DOI: 10.1016/j.bmc.2007.11.083] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2007] [Accepted: 11/30/2007] [Indexed: 11/26/2022]
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Spyranti Z, Dalkas GA, Spyroulias GA, Mantzourani ED, Mavromoustakos T, Friligou I, Matsoukas JM, Tselios TV. Putative Bioactive Conformations of Amide Linked Cyclic Myelin Basic Protein Peptide Analogues Associated with Experimental Autoimmune Encephalomyelitis. J Med Chem 2007; 50:6039-47. [DOI: 10.1021/jm070770m] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Zinovia Spyranti
- Departments of Pharmacy and Chemistry, University of Patras, GR-26504 Patras, Greece, and Institute of Organic and Pharmaceutical Chemistry, National Hellenic Research Foundation, GR-11635 Athens, Greece
| | - Georgios A. Dalkas
- Departments of Pharmacy and Chemistry, University of Patras, GR-26504 Patras, Greece, and Institute of Organic and Pharmaceutical Chemistry, National Hellenic Research Foundation, GR-11635 Athens, Greece
| | - Georgios A. Spyroulias
- Departments of Pharmacy and Chemistry, University of Patras, GR-26504 Patras, Greece, and Institute of Organic and Pharmaceutical Chemistry, National Hellenic Research Foundation, GR-11635 Athens, Greece
| | - Efthimia D. Mantzourani
- Departments of Pharmacy and Chemistry, University of Patras, GR-26504 Patras, Greece, and Institute of Organic and Pharmaceutical Chemistry, National Hellenic Research Foundation, GR-11635 Athens, Greece
| | - Thomas Mavromoustakos
- Departments of Pharmacy and Chemistry, University of Patras, GR-26504 Patras, Greece, and Institute of Organic and Pharmaceutical Chemistry, National Hellenic Research Foundation, GR-11635 Athens, Greece
| | - Irene Friligou
- Departments of Pharmacy and Chemistry, University of Patras, GR-26504 Patras, Greece, and Institute of Organic and Pharmaceutical Chemistry, National Hellenic Research Foundation, GR-11635 Athens, Greece
| | - John M. Matsoukas
- Departments of Pharmacy and Chemistry, University of Patras, GR-26504 Patras, Greece, and Institute of Organic and Pharmaceutical Chemistry, National Hellenic Research Foundation, GR-11635 Athens, Greece
| | - Theodore V. Tselios
- Departments of Pharmacy and Chemistry, University of Patras, GR-26504 Patras, Greece, and Institute of Organic and Pharmaceutical Chemistry, National Hellenic Research Foundation, GR-11635 Athens, Greece
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Xia J, Bergseng E, Fleckenstein B, Siegel M, Kim CY, Khosla C, Sollid LM. Cyclic and dimeric gluten peptide analogues inhibiting DQ2-mediated antigen presentation in celiac disease. Bioorg Med Chem 2007; 15:6565-73. [PMID: 17681795 PMCID: PMC2034199 DOI: 10.1016/j.bmc.2007.07.001] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2007] [Revised: 07/06/2007] [Accepted: 07/09/2007] [Indexed: 01/28/2023]
Abstract
Celiac disease is an immune mediated enteropathy elicited by gluten ingestion. The disorder has a strong association with HLA-DQ2. This HLA molecule is involved in the disease pathogenesis by presenting gluten peptides to T cells. Blocking the peptide-binding site of DQ2 may be a way to treat celiac disease. In this study, two types of peptide analogues, modeled after natural gluten antigens, were studied as DQ2 blockers. (a) Cyclic peptides. Cyclic peptides containing the DQ2-alphaI gliadin epitope LQPFPQPELPY were synthesized with flanking cysteine residues introduced and subsequently crosslinked via a disulfide bond. Alternatively, cyclic peptides were prepared with stable polyethylene glycol bridges across internal lysine residues of modified antigenic peptides such as KQPFPEKELPY and LQLQPFPQPEKPYPQPEKPY. The effect of cyclization as well as the length of the spacer in the cyclic peptides on DQ2 binding and T cell recognition was analyzed. Inhibition of peptide-DQ2 recognition by the T cell receptor was observed in T cell proliferation assays. (b) Dimeric peptides. Previously we developed a new type of peptide blocker with much enhanced affinity for DQ2 by dimerizing LQLQPFPQPEKPYPQPELPY through the lysine side chains. Herein, the effect of linker length on both DQ2 binding and T cell inhibition was investigated. One dimeric peptide analogue with an intermediate linker length was found to be especially effective at inhibiting DQ2 mediated antigen presentation. The implications of these findings for the treatment of celiac disease are discussed.
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Affiliation(s)
- Jiang Xia
- Department of Chemistry, Stanford University, Stanford, USA
| | - Elin Bergseng
- Institute of Immunology, University of Oslo, Rikshospitalet-Radiumhospitalet Medical Center, Oslo, Norway
| | - Burkhard Fleckenstein
- Institute of Immunology, University of Oslo, Rikshospitalet-Radiumhospitalet Medical Center, Oslo, Norway
| | - Matthew Siegel
- Department of Chemical Engineering, Stanford University, Stanford, USA
| | - Chu-Young Kim
- Department of Biological Sciences, National University of Singapore, Singapore
| | - Chaitan Khosla
- Department of Chemistry, Stanford University, Stanford, USA
- Department of Chemical Engineering, Stanford University, Stanford, USA
- Department of Biochemistry, Stanford University, Stanford, USA
- * Corresponding authors. Ludvig M. Sollid, Institute of Immunology, University of Oslo, Rikshospitalet-Radiumhospitalet Medical Center, N-0027 Oslo, Norway, Tel. +47 23073500; Fax. +47 23073510; E-mail: or Chaitan Khosla, Departments of Chemistry, Chemical Engineering and Biochemistry, Stanford University, Stanford, California 94305-5025, Tel. 650-723-6538; Fax.650-725-7294; E-mail:
| | - Ludvig M. Sollid
- Institute of Immunology, University of Oslo, Rikshospitalet-Radiumhospitalet Medical Center, Oslo, Norway
- * Corresponding authors. Ludvig M. Sollid, Institute of Immunology, University of Oslo, Rikshospitalet-Radiumhospitalet Medical Center, N-0027 Oslo, Norway, Tel. +47 23073500; Fax. +47 23073510; E-mail: or Chaitan Khosla, Departments of Chemistry, Chemical Engineering and Biochemistry, Stanford University, Stanford, California 94305-5025, Tel. 650-723-6538; Fax.650-725-7294; E-mail:
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55
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Mantzourani ED, Platts JA, Brancale A, Mavromoustakos TM, Tselios TV. Molecular dynamics at the receptor level of immunodominant myelin basic protein epitope 87-99 implicated in multiple sclerosis and its antagonists altered peptide ligands: triggering of immune response. J Mol Graph Model 2007; 26:471-81. [PMID: 17392002 DOI: 10.1016/j.jmgm.2007.02.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2007] [Revised: 02/14/2007] [Accepted: 02/20/2007] [Indexed: 11/18/2022]
Abstract
This work reports molecular dynamics studies at the receptor level of the immunodominant myelin basic protein (MBP) epitope 87-99 implicated in multiple sclerosis, and its antagonists altered peptide ligands (APLs), namely [Arg91, Ala96] MBP87-99 and [Ala91,96] MBP87-99. The interaction of each peptide ligand with the receptor human leukocyte antigen HLA-DR2b was studied, starting from X-ray structure with pdb code: 1ymm. This is the first such study of APL-HLA-DR2b complexes, and hence the first attempt to gain a better understanding of the molecular recognition mechanisms that underlie TCR antagonism by these APLs. The amino acids His88 and Phe89 serve as T-cell receptor (TCR) anchors in the formation of the trimolecular complex TCR-peptide-HLA-DR2b, where the TCR binds in a diagonal, off-centered mode to the peptide-HLA complex. The present findings indicate that these two amino acids have a different orientation in the APLs [Arg91, Ala96] MBP87-99 and [Ala91,96] MBP87-99: His88 and Phe89 remain buried in HLA grooves and are not available for interaction with the TCR. We propose that this different topology could provide a possible mechanism of action for TCR antagonism.
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Affiliation(s)
- Efthimia D Mantzourani
- Institute of Organic and Pharmaceutical Chemistry, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 116 35 Athens, Greece
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56
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Mantzourani ED, Tselios TV, Grdadolnik SG, Platts JA, Brancale A, Deraos GN, Matsoukas JM, Mavromoustakos TM. Comparison of Proposed Putative Active Conformations of Myelin Basic Protein Epitope 87−99 Linear Altered Peptide Ligands by Spectroscopic and Modelling Studies: The Role of Positions 91 and 96 in T-Cell Receptor Activation. J Med Chem 2006; 49:6683-91. [PMID: 17154499 DOI: 10.1021/jm060040z] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
This work proposes a structural motif for the inhibition of experimental autoimmune encephalomyelitis (EAE) by the linear altered peptide ligands (APLs) [Ala91,96] MBP87-99 and [Arg91,Ala96] MBP87-99 of myelin basic protein. Molecular dynamics was applied to reveal distinct populations of EAE antagonist [Ala91,96] MBP87-99 in solution, in agreement with NOE data. The combination of the theoretical and experimental results led to the identification of a putative active conformation. This approach is of value as no crystallographic data is available for the APL-receptor complex. TCR contact residue Phe89 has an altered topology in the putative bioactive conformations of both APLs with respect to the native peptide, as found via crystallography; it is no longer prominent and solvent exposed. It is proposed that the antagonistic activity of the APLs is due to their binding to MHC, preventing the binding of self-myelin epitopes, with the absence of an immunologic response as the loss of some interactions with the TCR hinders activation of T-cells.
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Affiliation(s)
- Efthimia D Mantzourani
- National Hellenic Research Foundation, Institute of Organic and Pharmaceutical Chemistry, 48 Vassileos Constantinou Avenue, 116 35, Athens, Greece
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57
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Mantzourani ED, Tselios TV, Grdadolnik SG, Brancale A, Platts JA, Matsoukas JM, Mavromoustakos TM. A putative bioactive conformation for the altered peptide ligand of myelin basic protein and inhibitor of experimental autoimmune encephalomyelitis [Arg91, Ala96] MBP87–99. J Mol Graph Model 2006; 25:17-29. [PMID: 16310386 DOI: 10.1016/j.jmgm.2005.09.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2005] [Revised: 09/22/2005] [Accepted: 09/29/2005] [Indexed: 11/21/2022]
Abstract
[Arg(91), Ala(96)] MBP(87-99) is an altered peptide ligand (APL) of myelin basic protein (MBP), shown to actively inhibit experimental autoimmune encephalomyelitis (EAE), which is studied as a model of multiple sclerosis (MS). The APL has been rationally designed by substituting two of the critical residues for recognition by the T-cell receptor. A conformational analysis of the APL has been sought using a combination of 2D NOESY nuclear magnetic resonance (NMR) experiments and detailed molecular dynamics (MD) calculations, in order to comprehend the stereoelectronic requirements for antagonistic activity, and to propose a putative bioactive conformation based on spatial proximities of the native peptide in the crystal structure. The proposed structure presents backbone similarity with the native peptide especially at the N-terminus, which is important for major histocompatibility complex (MHC) binding. Primary (Val(87), Phe(90)) and secondary (Asn(92), Ile(93), Thr(95)) MHC anchors occupy the same region in space, whereas T-cell receptor (TCR) contacts (His(88), Phe(89)) have different orientation between the two structures. A possible explanation, thus, of the antagonistic activity of the APL is that it binds to MHC, preventing the binding of myelin epitopes, but it fails to activate the TCR and hence to trigger the immunologic response. NMR experiments coupled with theoretical calculations are found to be in agreement with X-ray crystallography data and open an avenue for the design and synthesis of novel peptide restricted analogues as well as peptide mimetics that rises as an ultimate goal.
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Affiliation(s)
- E D Mantzourani
- National Hellenic Research Foundation, Institute of Organic and Pharmaceutical Chemistry, 48 Vassileos Constantinou Avenue, 116 35 Athens, Greece
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58
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Farès C, Libich DS, Harauz G. Solution NMR structure of an immunodominant epitope of myelin basic protein. Conformational dependence on environment of an intrinsically unstructured protein. FEBS J 2006; 273:601-14. [PMID: 16420483 DOI: 10.1111/j.1742-4658.2005.05093.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Using solution NMR spectroscopy, three-dimensional structures have been obtained for an 18-residue synthetic polypeptide fragment of 18.5 kDa myelin basic protein (MBP, human residues Q81-T98) under three conditions emulating the protein's natural environment in the myelin membrane to varying degrees: (a) an aqueous solution (100 mM KCl pH 6.5), (b) a mixture of trifluoroethanol (TFE-d2) and water (30 : 70% v/v), and (c) a dispersion of 100 mM dodecylphosphocholine (DPC-d38, 1 : 100 protein/lipid molar ratio) micelles. This polypeptide sequence is highly conserved in MBP from mammals, amphibians, and birds, and comprises a major immunodominant epitope (human residues N83-T92) in the autoimmune disease multiple sclerosis. In the polypeptide fragment, this epitope forms a stable, amphipathic, alpha helix under organic and membrane-mimetic conditions, but has only a partially helical conformation in aqueous solution. These results are consistent with recent molecular dynamics simulations that showed this segment to have a propensity to form a transient alpha helix in aqueous solution, and with electron paramagnetic resonance (EPR) experiments that suggested a alpha-helical structure when bound to a membrane [I. R. Bates, J. B. Feix, J. M. Boggs & G. Harauz (2004) J Biol Chem, 279, 5757-5764]. The high sensitivity of the epitope structure to its environment is characteristic of intrinsically unstructured proteins, like MBP, and reflects its association with diverse ligands such as lipids and other proteins.
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Affiliation(s)
- Christophe Farès
- Department of Molecular and Cellular Biology, and Biophysics Interdepartmental Group, University of Guelph, Canada
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59
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Abstract
Multiple sclerosis (MS) is an autoimmune disease associated with chronic inflammatory demyelination of the central nervous system in genetically susceptible individuals. Because of the disease complexity and heterogeneity, its pathogenesis remains unknown despite extensive research efforts, and specific effective treatments have not yet been developed. Peptide-based research has been important in attempts to unravel particular aspects of this complex disease, including the characterization of the different molecular mechanisms of MS, with the goal of providing useful products for immune-mediated therapies. In fact, in the past decade, peptide-based research has been predominant in research aimed to identify and/or develop target antigens as synthetic probes for specific biomarkers as well as innovative immunomodulating therapies. This review presents an overview of the contributions of peptide science to MS research and discusses future directions of peptide-based investigations.
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Affiliation(s)
- Maria Claudia Alcaro
- Laboratory of Peptide and Protein Chemistry and Biology, Dipartimento di Chimica Organica, University of Firenze, Polo Scientifico, via della Lastruccia 13, I-50019 Sesto Fiorentino (FI), Italy
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