1
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Sarango G, Richetta C, Pereira M, Kumari A, Ghosh M, Bertrand L, Pionneau C, Le Gall M, Grégoire S, Jeger‐Madiot R, Rosoy E, Subra F, Delelis O, Faure M, Esclatine A, Graff‐Dubois S, Stevanović S, Manoury B, Ramirez BC, Moris A. The Autophagy Receptor TAX1BP1 (T6BP) improves antigen presentation by MHC-II molecules. EMBO Rep 2022; 23:e55470. [PMID: 36215666 PMCID: PMC9724678 DOI: 10.15252/embr.202255470] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 09/16/2022] [Accepted: 09/23/2022] [Indexed: 12/12/2022] Open
Abstract
CD4+ T lymphocytes play a major role in the establishment and maintenance of immunity. They are activated by antigenic peptides derived from extracellular or newly synthesized (endogenous) proteins presented by the MHC-II molecules. The pathways leading to endogenous MHC-II presentation remain poorly characterized. We demonstrate here that the autophagy receptor, T6BP, influences both autophagy-dependent and -independent endogenous presentation of HIV- and HCMV-derived peptides. By studying the immunopeptidome of MHC-II molecules, we show that T6BP affects both the quantity and quality of peptides presented. T6BP silencing induces the mislocalization of the MHC-II-loading compartments and rapid degradation of the invariant chain (CD74) without altering the expression and internalization kinetics of MHC-II molecules. Defining the interactome of T6BP, we identify calnexin as a T6BP partner. We show that the calnexin cytosolic tail is required for this interaction. Remarkably, calnexin silencing replicates the functional consequences of T6BP silencing: decreased CD4+ T cell activation and exacerbated CD74 degradation. Altogether, we unravel T6BP as a key player of the MHC-II-restricted endogenous presentation pathway, and we propose one potential mechanism of action.
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Affiliation(s)
- Gabriela Sarango
- Université Paris‐Saclay, CEA, CNRSInstitute for Integrative Biology of the Cell (I2BC)Gif‐sur‐YvetteFrance,Sorbonne UniversitéINSERM, CNRS, Center for Immunology and Microbial Infections (CIMI‐Paris)ParisFrance
| | - Clémence Richetta
- Sorbonne UniversitéINSERM, CNRS, Center for Immunology and Microbial Infections (CIMI‐Paris)ParisFrance,LBPA, ENS‐Paris Saclay, CNRS UMR8113Université Paris SaclayGif‐sur‐YvetteFrance
| | - Mathias Pereira
- Université Paris‐Saclay, CEA, CNRSInstitute for Integrative Biology of the Cell (I2BC)Gif‐sur‐YvetteFrance,Sorbonne UniversitéINSERM, CNRS, Center for Immunology and Microbial Infections (CIMI‐Paris)ParisFrance
| | - Anita Kumari
- Université Paris‐Saclay, CEA, CNRSInstitute for Integrative Biology of the Cell (I2BC)Gif‐sur‐YvetteFrance,Sorbonne UniversitéINSERM, CNRS, Center for Immunology and Microbial Infections (CIMI‐Paris)ParisFrance
| | - Michael Ghosh
- Department of Immunology, Institute for Cell BiologyUniversity of TübingenTübingenGermany
| | - Lisa Bertrand
- Université Paris‐Saclay, CEA, CNRSInstitute for Integrative Biology of the Cell (I2BC)Gif‐sur‐YvetteFrance,Sorbonne UniversitéINSERM, CNRS, Center for Immunology and Microbial Infections (CIMI‐Paris)ParisFrance
| | - Cédric Pionneau
- Sorbonne UniversitéINSERM, UMS Production et Analyse de Données en Sciences de la vie et en Santé, PASS, Plateforme Post‐génomique de la Pitié SalpêtrièreParisFrance
| | - Morgane Le Gall
- 3P5 proteom'IC facilityUniversité de Paris, Institut Cochin, INSERM U1016, CNRS‐UMR 8104ParisFrance
| | - Sylvie Grégoire
- Université Paris‐Saclay, CEA, CNRSInstitute for Integrative Biology of the Cell (I2BC)Gif‐sur‐YvetteFrance,Sorbonne UniversitéINSERM, CNRS, Center for Immunology and Microbial Infections (CIMI‐Paris)ParisFrance
| | - Raphaël Jeger‐Madiot
- Sorbonne UniversitéINSERM, CNRS, Center for Immunology and Microbial Infections (CIMI‐Paris)ParisFrance,Present address:
Sorbonne Université, INSERM U959, Immunology‐Immunopathology‐Immunotherapy (i3)ParisFrance
| | - Elina Rosoy
- Sorbonne UniversitéINSERM, CNRS, Center for Immunology and Microbial Infections (CIMI‐Paris)ParisFrance
| | - Frédéric Subra
- LBPA, ENS‐Paris Saclay, CNRS UMR8113Université Paris SaclayGif‐sur‐YvetteFrance
| | - Olivier Delelis
- LBPA, ENS‐Paris Saclay, CNRS UMR8113Université Paris SaclayGif‐sur‐YvetteFrance
| | - Mathias Faure
- CIRI, Centre International de Recherche en Infectiologie, Université de Lyon, Inserm U1111Université Claude Bernard Lyon 1, CNRS, UMR5308, ENS de LyonLyonFrance,Equipe Labellisée par la Fondation pour la Recherche Médicale, FRM
| | - Audrey Esclatine
- Université Paris‐Saclay, CEA, CNRSInstitute for Integrative Biology of the Cell (I2BC)Gif‐sur‐YvetteFrance
| | - Stéphanie Graff‐Dubois
- Sorbonne UniversitéINSERM, CNRS, Center for Immunology and Microbial Infections (CIMI‐Paris)ParisFrance,Present address:
Sorbonne Université, INSERM U959, Immunology‐Immunopathology‐Immunotherapy (i3)ParisFrance
| | - Stefan Stevanović
- Department of Immunology, Institute for Cell BiologyUniversity of TübingenTübingenGermany
| | - Bénédicte Manoury
- Institut Necker Enfants Malades, INSERM U1151‐CNRS UMR 8253, Faculté de médecine NeckerUniversité de ParisParisFrance
| | - Bertha Cecilia Ramirez
- Université Paris‐Saclay, CEA, CNRSInstitute for Integrative Biology of the Cell (I2BC)Gif‐sur‐YvetteFrance,Sorbonne UniversitéINSERM, CNRS, Center for Immunology and Microbial Infections (CIMI‐Paris)ParisFrance
| | - Arnaud Moris
- Université Paris‐Saclay, CEA, CNRSInstitute for Integrative Biology of the Cell (I2BC)Gif‐sur‐YvetteFrance,Sorbonne UniversitéINSERM, CNRS, Center for Immunology and Microbial Infections (CIMI‐Paris)ParisFrance
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2
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Álvaro-Benito M, Freund C. Revisiting nonclassical HLA II functions in antigen presentation: Peptide editing and its modulation. HLA 2020; 96:415-429. [PMID: 32767512 DOI: 10.1111/tan.14007] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 08/04/2020] [Indexed: 01/08/2023]
Abstract
The nonclassical major histocompatibility complex of class II molecules (ncMHCII) HLA-DM (DM) and HLA-DO (DO) feature essential functions for the selection of the peptides that are displayed by classical MHCII proteins (MHCII) for CD4+ Th cell surveillance. Thus, although the binding groove of classical MHCII dictates the main features of the peptides displayed, ncMHCII function defines the preferential loading of peptides from specific cellular compartments and the extent to which they are presented. DM acts as a chaperone for classical MHCII molecules facilitating peptide exchange and thereby favoring the binding of peptide-MHCII complexes of high kinetic stability mostly in late endosomal compartments. DO on the other hand binds to DM blocking its peptide-editing function in B cells and thymic epithelial cells, limiting DM activity in these cellular subsets. DM and DO distinct expression patterns therefore define specific antigen presentation profiles that select unique peptide pools for each set of antigen presenting cell. We have come a long way understanding the mechanistic underpinnings of such distinct editing profiles and start to grasp the implications for ncMHCII biological function. DM acts as filter for the selection of immunodominant, pathogen-derived epitopes while DO blocks DM activity under certain physiological conditions to promote tolerance to self. Interestingly, recent findings have shown that the unexplored and neglected ncMHCII genetic diversity modulates retroviral infection in mouse, and affects human ncMHCII function. This review aims at highlighting the importance of ncMHCII function for CD4+ Th cell responses while integrating and evaluating what could be the impact of distinct editing profiles because of natural genetic variations.
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Affiliation(s)
- Miguel Álvaro-Benito
- Laboratory of Protein Biochemistry, Institute für Chemie und Biochemie, Department of Biology, Chemistry, Pharmacy, Freie Universität Berlin, Berlin, Germany
| | - Christian Freund
- Laboratory of Protein Biochemistry, Institute für Chemie und Biochemie, Department of Biology, Chemistry, Pharmacy, Freie Universität Berlin, Berlin, Germany
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3
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Clement CC, Becerra A, Yin L, Zolla V, Huang L, Merlin S, Follenzi A, Shaffer SA, Stern LJ, Santambrogio L. The Dendritic Cell Major Histocompatibility Complex II (MHC II) Peptidome Derives from a Variety of Processing Pathways and Includes Peptides with a Broad Spectrum of HLA-DM Sensitivity. J Biol Chem 2016; 291:5576-5595. [PMID: 26740625 DOI: 10.1074/jbc.m115.655738] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Indexed: 12/26/2022] Open
Abstract
The repertoire of peptides displayed in vivo by MHC II molecules derives from a wide spectrum of proteins produced by different cell types. Although intracellular endosomal processing in dendritic cells and B cells has been characterized for a few antigens, the overall range of processing pathways responsible for generating the MHC II peptidome are currently unclear. To determine the contribution of non-endosomal processing pathways, we eluted and sequenced over 3000 HLA-DR1-bound peptides presented in vivo by dendritic cells. The processing enzymes were identified by reference to a database of experimentally determined cleavage sites and experimentally validated for four epitopes derived from complement 3, collagen II, thymosin β4, and gelsolin. We determined that self-antigens processed by tissue-specific proteases, including complement, matrix metalloproteases, caspases, and granzymes, and carried by lymph, contribute significantly to the MHC II self-peptidome presented by conventional dendritic cells in vivo. Additionally, the presented peptides exhibited a wide spectrum of binding affinity and HLA-DM susceptibility. The results indicate that the HLA-DR1-restricted self-peptidome presented under physiological conditions derives from a variety of processing pathways. Non-endosomal processing enzymes add to the number of epitopes cleaved by cathepsins, altogether generating a wider peptide repertoire. Taken together with HLA-DM-dependent and-independent loading pathways, this ensures that a broad self-peptidome is presented by dendritic cells. This work brings attention to the role of "self-recognition" as a dynamic interaction between dendritic cells and the metabolic/catabolic activities ongoing in every parenchymal organ as part of tissue growth, remodeling, and physiological apoptosis.
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Affiliation(s)
| | | | | | | | | | - Simone Merlin
- the School of Medicine, University of Piemonte Orientale, 28100 Novara, Italy
| | - Antonia Follenzi
- From the Departments of Pathology and; the School of Medicine, University of Piemonte Orientale, 28100 Novara, Italy
| | - Scott A Shaffer
- Biochemistry and Molecular Pharmacology and; the Proteomics and Mass Spectrometry Facility, University of Massachusetts Medical School, Worcester, Massachusetts 01655, and
| | - Lawrence J Stern
- the Departments of Pathology and; Biochemistry and Molecular Pharmacology and
| | - Laura Santambrogio
- From the Departments of Pathology and; Microbiology and Immunology, Albert Einstein College of Medicine, New York, New York 10461,.
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4
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Leung CSK. Endogenous Antigen Presentation of MHC Class II Epitopes through Non-Autophagic Pathways. Front Immunol 2015; 6:464. [PMID: 26441969 PMCID: PMC4563256 DOI: 10.3389/fimmu.2015.00464] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 08/25/2015] [Indexed: 12/30/2022] Open
Abstract
Antigenic peptides presented by major histocompatibility complex (MHC) class II molecules are generally derived from exogenous proteins acquired by antigen presenting cells. However, in some circumstances, MHC class II molecules can present intracellular proteins expressed within the antigen-presenting cells. There are several described pathways by which endogenous antigens are degraded and gain access to MHC class II molecules. These include autophagy and other non-autophagic pathways; the latter category includes the MHC class I-like pathways, heat shock protein 90-mediated pathways, and internalization from the plasma membrane. This review will summarize and discuss the non-autophagic pathways.
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Affiliation(s)
- Carol S K Leung
- Department of Haematology, University College London Cancer Institute, University College London , London , UK
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5
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Deficient import of acetyl-CoA into the ER lumen causes neurodegeneration and propensity to infections, inflammation, and cancer. J Neurosci 2014; 34:6772-89. [PMID: 24828632 DOI: 10.1523/jneurosci.0077-14.2014] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The import of acetyl-CoA into the ER lumen by AT-1/SLC33A1 is essential for the N(ε)-lysine acetylation of ER-resident and ER-transiting proteins. A point-mutation (S113R) in AT-1 has been associated with a familial form of spastic paraplegia. Here, we report that AT-1S113R is unable to form homodimers in the ER membrane and is devoid of acetyl-CoA transport activity. The reduced influx of acetyl-CoA into the ER lumen results in reduced acetylation of ER proteins and an aberrant form of autophagy. Mice homozygous for the mutation display early developmental arrest. In contrast, heterozygous animals develop to full term, but display neurodegeneration and propensity to infections, inflammation, and cancer. The immune and cancer phenotypes are contingent on the presence of pathogens in the colony, whereas the nervous system phenotype is not. In conclusion, our results reveal a previously unknown aspect of acetyl-CoA metabolism that affects the immune and nervous systems and the risk for malignancies.
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6
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Autoantibodies to IgG/HLA class II complexes are associated with rheumatoid arthritis susceptibility. Proc Natl Acad Sci U S A 2014; 111:3787-92. [PMID: 24567378 DOI: 10.1073/pnas.1401105111] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Specific HLA class II alleles are strongly associated with susceptibility to rheumatoid arthritis (RA); however, how HLA class II regulates susceptibility to RA has remained unclear. Recently, we found a unique function of HLA class II molecules: their ability to aberrantly transport cellular misfolded proteins to the cell surface without processing to peptides. Rheumatoid factor (RF) is an autoantibody that binds to denatured IgG or Fc fragments of IgG and is detected in 70-80% of RA patients but also in patients with other diseases. Here, we report that intact IgG heavy chain (IgGH) is transported to the cell surface by HLA class II via association with the peptide-binding groove and that IgGH/HLA class II complexes are specifically recognized by autoantibodies in RF-positive sera from RA patients. In contrast, autoantibodies in RF-positive sera from non-RA individuals did not bind to IgGH/HLA class II complexes. Of note, a strong correlation between autoantibody binding to IgG complexed with certain HLA-DR alleles and the odds ratio for that allele's association with RA was observed (r = 0.81; P = 4.6 × 10(-5)). Our findings suggest that IgGH complexed with certain HLA class II alleles is a target for autoantibodies in RA, which might explain why these HLA class II alleles confer susceptibility to RA.
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7
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Abstract
Autophagy is a specialized cellular pathway involved in maintaining homeostasis by degrading long-lived cellular proteins and organelles. Recent studies have demonstrated that autophagy is utilized by immune systems to protect host cells from invading pathogens and regulate uncontrolled immune responses. During pathogen recognition, induction of autophagy by pattern recognition receptors leads to the promotion or inhibition of consequent signaling pathways. Furthermore, autophagy plays a role in the delivery of pathogen signatures in order to promote the recognition thereof by pattern recognition receptors. In addition to innate recognition, autophagy has been shown to facilitate MHC class II presentation of intracellular antigens to activate CD4 T cells. In this review, we describe the roles of autophagy in innate recognition of pathogens and adaptive immunity, such as antigen presentation, as well as the clinical relevance of autophagy in the treatment of human diseases.
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Affiliation(s)
- Ji Eun Oh
- Laboratory of Host Defenses, Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Korea
| | - Heung Kyu Lee
- Laboratory of Host Defenses, Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Korea
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8
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Muixí L, Contreras V, Collado JA, Alexandre Y, Ballingall K, Bonneau M, Jaraquemada D, Schwartz-Cornil I. Unraveling features of the natural MHC class II peptidome of skin-migrated dendritic cells. Int Immunol 2011; 24:59-69. [PMID: 22194283 DOI: 10.1093/intimm/dxr096] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Dendritic cells (DCs) migrating from peripheral tissues at steady state are considered the most efficient antigen-presenting cells (APCs) involved in the induction of peripheral T-cell tolerance via self-antigen presentation on MHC class II molecules. However, difficulties in obtaining sufficient numbers of such DCs have precluded previous analyses of their natural MHC class II peptidome in laboratory animals or humans. Here, we overcome this difficulty by collecting the large quantities of sheep DCs that migrate from the skin via the afferent lymphatics at steady state to the draining lymph node. We compared the repertoire of MHC class II-bound peptides from afferent lymph DCs with autologous APCs derived from peripheral blood. A large fraction of the MHC class II peptidome from skin DCs was derived from membrane-recycling proteins (59%) and from proteins of the antigen presentation machinery (50%), whereas these types of peptides constituted a more limited fraction in blood APCs (21 and 11%, respectively). One sheep cytokeratin peptide was identified in the skin DC peptidome indicating active processing of epithelium-derived antigens. Conversely, peptides derived from cytosolic and soluble antigens of the extracellular milieu were more represented in blood APCs than skin DCs. The biased peptidome of skin-migrated DCs indicates that these cells express a peptide repertoire for the generation of self-reactive and/or regulatory T cells mainly directed toward DC molecules from internal and external membranes and to a lesser extent toward antigens of the extracellular milieu, including some tissue-specific peptides.
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Affiliation(s)
- Laia Muixí
- Immunology Unit, Institut de Biotecnologia i Biomedicina (IBB), Universitat Autònoma de Barcelona (UAB), 08193 Bellaterra, Barcelona, Spain
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9
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Münz C. Antigen processing by macroautophagy for MHC presentation. Front Immunol 2011; 2:42. [PMID: 22566832 PMCID: PMC3342048 DOI: 10.3389/fimmu.2011.00042] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2011] [Accepted: 08/22/2011] [Indexed: 12/16/2022] Open
Abstract
T cells recognize antigen fragments, presented to them by MHC molecules. It lies in the interest of the immune system to display a maximal diversity of these peptides and utilize all catabolic processes to generate them. Macroautophagy, a pathway that delivers cytoplasmic constituents for lysosomal degradation is no exception. In recent years, it has become apparent that macroautophagy assists in intra- and extracellular antigen processing for MHC class II presentation to CD4+ helper T cells. Surprisingly, however, macroautophagy also assists in antigen packaging for better cross-presentation on MHC molecules of bystander cells, which could be consistent with its role in unconventional protein secretion. These three pathways of antigen processing for MHC presentation via macroautophagy will be discussed in this review and cell biological aspects will be high-lighted that might explain, how the molecular machinery of macroautophagy might assist these diverse antigen processing pathways.
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Affiliation(s)
- Christian Münz
- Viral Immunobiology, Institute of Experimental Immunology, University of Zürich Zürich, Switzerland.
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10
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Muixí L, Gay M, Muñoz-Torres PM, Guitart C, Cedano J, Abian J, Alvarez I, Jaraquemada D. The peptide-binding motif of HLA-DR8 shares important structural features with other type 1 diabetes-associated alleles. Genes Immun 2011; 12:504-12. [PMID: 21654843 DOI: 10.1038/gene.2011.26] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The objective of this study was to characterize the peptide-binding motif of the major histocompatibility complex (MHC) class II HLA-DR8 molecule included in the type 1 diabetes-associated haplotype DRB1(*)0801-DQA1(*)0401/DQB1(*)0402 (DR8-DQ4), and compare it with that of other diabetes-associated MHC class II alleles; DR8-bound peptides were eluted from an HLA-DR homozygous lymphoblastoid cell line. The repertoire was characterized by peptide sequencing using a LTQ ion trap mass spectrometer coupled to a multidimensional liquid chromatography system. After validation of the spectra identification, the definition of the HLA-DR8 peptide-binding motif was achieved from the analysis of 486 natural ligands, based on serial alignments of all possible HLA-DR-binding cores. The DR8 motif showed a strong similarity with the peptide-binding motifs of other MHC class II diabetes-associated alleles, HLA-DQ8 and H-2 I-A(g7). Similar to HLA-DQ8 and H-2 I-A(g7), HLA-DR8 preferentially binds peptides with an acidic residue at position P9 of the binding core, indicating that DR8 is the susceptibility component of the DR8-DQ4 haplotype. Indeed, some DR8 peptides were identical to peptides previously identified as DQ8- or I-A(g7) ligands, and several diabetes-specific peptides associated with DQ8 or I-A(g7) could theoretically bind to HLA-DR8. These data further strengthen the association of HLA-DR8 with type I diabetes.
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Affiliation(s)
- L Muixí
- Department of Cell Biology, Physiology and Immunology, Immunology Unit, Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Barcelona, Spain
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11
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Del Val M, Iborra S, Ramos M, Lázaro S. Generation of MHC class I ligands in the secretory and vesicular pathways. Cell Mol Life Sci 2011; 68:1543-52. [PMID: 21387141 PMCID: PMC11114776 DOI: 10.1007/s00018-011-0661-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2011] [Revised: 02/17/2011] [Accepted: 02/18/2011] [Indexed: 12/13/2022]
Abstract
CD8(+) T lymphocytes screen the surface of all cells in the body to detect pathogen infection or oncogenic transformation. They recognize peptides derived from cellular proteins displayed at the plasma membrane by major histocompatibility complex (MHC) class I molecules. Peptides are mostly by-products of cytosolic proteolytic enzymes. Peptidic ligands of MHC class I molecules are also generated in the secretory and vesicular pathways. Features of protein substrates, of proteases and of available MHC class I molecules for loading peptides in these compartments shape a singular collection of ligands that also contain different, longer, and lower affinity peptides than ligands produced in the cytosol. Especially in individuals who lack the transporters associated with antigen processing, TAP, and in infected and tumor cells where TAP is blocked, which thus have no supply of peptides derived from the cytosol, MHC class I ligands generated in the secretory and vesicular pathways contribute to shaping the CD8(+) T lymphocyte response.
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Affiliation(s)
- Margarita Del Val
- Unidad de Inmunología Viral, Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Nicolás Cabrera 1, Universidad Autónoma de Madrid, Campus Cantoblanco, 28049 Madrid, Spain,
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12
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Ravikumar B, Sarkar S, Davies JE, Futter M, Garcia-Arencibia M, Green-Thompson ZW, Jimenez-Sanchez M, Korolchuk VI, Lichtenberg M, Luo S, Massey DCO, Menzies FM, Moreau K, Narayanan U, Renna M, Siddiqi FH, Underwood BR, Winslow AR, Rubinsztein DC. Regulation of mammalian autophagy in physiology and pathophysiology. Physiol Rev 2010; 90:1383-435. [PMID: 20959619 DOI: 10.1152/physrev.00030.2009] [Citation(s) in RCA: 1317] [Impact Index Per Article: 94.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
(Macro)autophagy is a bulk degradation process that mediates the clearance of long-lived proteins and organelles. Autophagy is initiated by double-membraned structures, which engulf portions of cytoplasm. The resulting autophagosomes ultimately fuse with lysosomes, where their contents are degraded. Although the term autophagy was first used in 1963, the field has witnessed dramatic growth in the last 5 years, partly as a consequence of the discovery of key components of its cellular machinery. In this review we focus on mammalian autophagy, and we give an overview of the understanding of its machinery and the signaling cascades that regulate it. As recent studies have also shown that autophagy is critical in a range of normal human physiological processes, and defective autophagy is associated with diverse diseases, including neurodegeneration, lysosomal storage diseases, cancers, and Crohn's disease, we discuss the roles of autophagy in health and disease, while trying to critically evaluate if the coincidence between autophagy and these conditions is causal or an epiphenomenon. Finally, we consider the possibility of autophagy upregulation as a therapeutic approach for various conditions.
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Affiliation(s)
- Brinda Ravikumar
- Department of Medical Genetics, University of Cambridge, Cambridge Institute for Medical Research, Addenbrooke’s Hospital, Cambridge, United Kingdom
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13
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Vyas JM, Van der Veen AG, Ploegh HL. The known unknowns of antigen processing and presentation. Nat Rev Immunol 2008; 8:607-18. [PMID: 18641646 PMCID: PMC2735460 DOI: 10.1038/nri2368] [Citation(s) in RCA: 425] [Impact Index Per Article: 26.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The principal components of both MHC class I and class II antigen processing and presentation pathways are well known. In dendritic cells, these pathways are tightly regulated by Toll-like-receptor signalling and include features, such as cross-presentation, that are not seen in other cell types. However, the exact mechanisms involved in the subcellular trafficking of antigens remain poorly understood and in some cases are controversial. Recent data suggest that diverse cellular machineries, including autophagy, participate in antigen processing and presentation, although their relative contributions remain to be fully elucidated. Here, we highlight some emerging themes of antigen processing and presentation that we think merit further attention.
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Affiliation(s)
- Jatin M Vyas
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts 02142, USA
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14
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Muixí L, Carrascal M, Alvarez I, Daura X, Martí M, Armengol MP, Pinilla C, Abian J, Pujol-Borrell R, Jaraquemada D. Thyroglobulin peptides associate in vivo to HLA-DR in autoimmune thyroid glands. THE JOURNAL OF IMMUNOLOGY 2008; 181:795-807. [PMID: 18566446 DOI: 10.4049/jimmunol.181.1.795] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Endocrine epithelial cells, targets of the autoimmune response in thyroid and other organ-specific autoimmune diseases, express HLA class II (HLA-II) molecules that are presumably involved in the maintenance and regulation of the in situ autoimmune response. HLA-II molecules thus expressed by thyroid cells have the "compact" conformation and are therefore expected to stably bind autologous peptides. Using a new approach to study in situ T cell responses without the characterization of self-reactive T cells and their specificity, we have identified natural HLA-DR-associated peptides in autoimmune organs that will allow finding peptide-specific T cells in situ. This study reports a first analysis of HLA-DR natural ligands from ex vivo Graves' disease-affected thyroid tissue. Using mass spectrometry, we identified 162 autologous peptides from HLA-DR-expressing cells, including thyroid follicular cells, with some corresponding to predominant molecules of the thyroid colloid. Most interestingly, eight of the peptides were derived from a major autoantigen, thyroglobulin. In vitro binding identified HLA-DR3 as the allele to which one of these peptides likely associates in vivo. Computer modeling and bioinformatics analysis suggested other HLA-DR alleles for binding of other thyroglobulin peptides. Our data demonstrate that although the HLA-DR-associated peptide pool in autoimmune tissue mostly belongs to abundant ubiquitous proteins, peptides from autoantigens are also associated to HLA-DR in vivo and therefore may well be involved in the maintenance and the regulation of the autoimmune response.
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Affiliation(s)
- Laia Muixí
- Immunology Unit, Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, Barcelona, Spain
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15
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Alvarez I, Collado J, Daura X, Colomé N, Rodríguez-García M, Gallart T, Canals F, Jaraquemada D. The rheumatoid arthritis-associated allele HLA-DR10 (DRB1*1001) shares part of its repertoire with HLA-DR1 (DRB1*0101) and HLA-DR4 (DRB*0401). ACTA ACUST UNITED AC 2008; 58:1630-9. [PMID: 18512783 DOI: 10.1002/art.23503] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
OBJECTIVE To identify the peptide anchor motif for the rheumatoid arthritis (RA)-related HLA allele, DR10, and find shared natural ligands or sequence similarities with the other disease-associated alleles, DR1 and DR4. METHODS The HLA-DR10-associated peptides were purified, and a proportion of these natural ligands were de novo sequenced by mass spectrometry. Based on crystallographic structures, the complexes formed by peptide influenza virus hemagglutinin HA306-318 with DR1, DR4, and DR10 were modeled, and binding scores were obtained. RESULTS A total of 238 peptides were sequenced, and the anchor motif of the HLA-DR10 peptide repertoire was defined. A large proportion of the DR10-associated peptides had the structural features to bind DR1 and DR4 but were theoretical nonbinders to the negatively associated alleles DR15 and DR7. Among the sequenced ligands, 10 had been reported as ligands to other RA-associated alleles. Modeling data showed that peptide HA306-318 can bind DR1, DR4, and DR10 with similar affinities. CONCLUSION The data show the presence of common peptides in the repertoires of RA-associated HLA alleles. The combination of the shared epitope present in DR1, DR4, and DR10 together with common putative arthritogenic peptide(s) could influence disease onset or outcome.
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16
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Muixí L, Alvarez I, Jaraquemada D. Peptides presented in vivo by HLA-DR in thyroid autoimmunity. Adv Immunol 2008; 99:165-209. [PMID: 19117535 DOI: 10.1016/s0065-2776(08)00606-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The association of the major histocompatibility complex (MHC) genes with autoimmune diseases together with the ectopic expression of class II molecules by epithelial cells of the target tissue gives to these molecules a central role in the pathogenesis of the disease, in its regulation and in the persistence of the immune response in situ. HLA-DR molecules expressed by thyroid follicular cells in thyroid autoimmune diseases are compact molecules stably associated with peptides. The nature of these peptides is of vital importance in the understanding of the disease, since these MHC-II-peptide complexes are going to be recognized by both effector and regulatory T cells in situ. In this chapter, we review the current state of the analysis of naturally processed peptides presented by MHC class II molecules in the context of autoimmunity and we discuss our data of natural HLA-DR ligands eluted from Graves' disease affected thyroid glands, from where autoantigen-derived peptides have been identified.
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Affiliation(s)
- Laia Muixí
- Immunology Unit, Institut de Biotechnologia i Biomedicina, Universitat Autònoma de Barcelona, Campus de Bellaterra, Barcelona, Spain
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17
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Villeneuve DJ, Hembruff SL, Veitch Z, Cecchetto M, Dew WA, Parissenti AM. cDNA microarray analysis of isogenic paclitaxel- and doxorubicin-resistant breast tumor cell lines reveals distinct drug-specific genetic signatures of resistance. Breast Cancer Res Treat 2005; 96:17-39. [PMID: 16322897 DOI: 10.1007/s10549-005-9026-6] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2005] [Accepted: 07/06/2005] [Indexed: 12/13/2022]
Abstract
cDNA microarray analysis is a highly useful tool for the classification of tumors and for prediction of patient prognosis to specific cancers based on this classification. However, to date, there is little evidence that microarray approaches can be used to reliably predict patient response to specific chemotherapy drugs or regimens. This is likely due to an inability to differentiate between genes affecting patient prognosis and genes that play a role in response to specific drugs. Thus, it would be highly useful to identify genes whose expression correlates with tumor cell sensitivity to specific chemotherapy agents in a drug-specific manner. Using cDNA microarray analysis of wildtype MCF-7 breast tumor cells and isogenic paclitaxel-resistant (MCF-7(TAX)) or doxorubicin-resistant (MCF-7(DOX)) derivative cell lines, we have uncovered drug-specific changes in gene expression that accompany the establishment of paclitaxel or doxorubicin resistance. These changes in gene expression were confirmed by quantitative reverse transcription polymerase chain reaction and immunoblotting experiments, with a confirmation rate of approximately 91-95%. The genes identified may prove highly useful for prediction of response to paclitaxel or doxorubicin in patients with breast cancer. To our knowledge this is the first report of drug-specific genetic signatures of resistance to paclitaxel or doxorubicin, based on a comparison of gene expression between isogenic wildtype and drug-resistant tumor cell lines. Moreover, this study provides significant insight into the wide variety of mechanisms through which resistance to these agents may be acquired in breast cancer.
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Affiliation(s)
- David J Villeneuve
- Tumor Biology Research Program, Sudbury Regional Hospital, Sudbury, Ont., Canada
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18
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Suri A, Lovitch SB, Unanue ER. The wide diversity and complexity of peptides bound to class II MHC molecules. Curr Opin Immunol 2005; 18:70-7. [PMID: 16316750 DOI: 10.1016/j.coi.2005.11.002] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2005] [Accepted: 11/10/2005] [Indexed: 01/25/2023]
Abstract
The identification and quantitation of peptides selected by class II MHC molecules during natural processing of proteins is of key importance in understanding the repertoire and distribution of T cells. The examination of peptides selected by class II MHC molecules has depended greatly on mass spectrometry, a powerful technique that identifies and sequences peptides in complex mixtures with great sensitivity and precision. Such analysis has resulted in the identification of several factors, including the repertoire of peptides selected by MHC molecules during natural processing of proteins, motifs important for selection of processed peptides, conformational isomers of peptide-MHC complexes, and post-translational changes to the peptides.
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Affiliation(s)
- Anish Suri
- Washington University School of Medicine, Department of Pathology and Immunology, 660 South Euclid Avenue, St. Louis, MO 63110, USA
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19
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Meiring HD, Kuipers B, van Gaans-van den Brink JAM, Poelen MCM, Timmermans H, Baart G, Brugghe H, van Schie J, Boog CJP, de Jong APJM, van Els CACM. Mass tag-assisted identification of naturally processed HLA class II-presented meningococcal peptides recognized by CD4+ T lymphocytes. THE JOURNAL OF IMMUNOLOGY 2005; 174:5636-43. [PMID: 15843563 DOI: 10.4049/jimmunol.174.9.5636] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The meningococcal class I outer membrane protein porin A plays an important role in the development of T cell-dependent protective immunity against meningococcal serogroup B infection and is therefore a major component of candidate meningococcal vaccines. T cell epitopes from porin A are poorly characterized because of weak in vitro memory T cell responses against purified Ag and strain variation. We applied a novel strategy to identify relevant naturally processed and MHC class II-presented porin A epitopes, based on stable isotope labeling of Ag. Human immature HLA-DR1-positive dendritic cells were used for optimal uptake and MHC class II processing of (14)N- and (15)N-labeled isoforms of the neisserial porin A serosubtype P1.5-2,10 in bacterial outer membrane vesicles. HLA-DR1 bound peptides, obtained after 48 h of Ag processing, contained typical spectral doublets in mass spectrometry that could easily be assigned to four porin A regions, expressed at diverging densities ( approximately 30-4000 copies/per cell). Epitopes from two of these regions are recognized by HLA-DR1-restricted CD4(+) T cell lines and are conserved among different serosubtypes of meningococcal porin A. This mass tag-assisted approach provides a useful methodology for rapid identification of MHC class II presented bacterial CD4(+) T cell epitopes relevant for vaccine development.
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Affiliation(s)
- Hugo D Meiring
- Laboratory of Analytical Chemistry, National Institute of Public Health and the Environment, Bilthoven, The Netherlands
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20
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Dengjel J, Schoor O, Fischer R, Reich M, Kraus M, Müller M, Kreymborg K, Altenberend F, Brandenburg J, Kalbacher H, Brock R, Driessen C, Rammensee HG, Stevanovic S. Autophagy promotes MHC class II presentation of peptides from intracellular source proteins. Proc Natl Acad Sci U S A 2005; 102:7922-7. [PMID: 15894616 PMCID: PMC1142372 DOI: 10.1073/pnas.0501190102] [Citation(s) in RCA: 494] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2005] [Indexed: 02/08/2023] Open
Abstract
MHC-peptide complexes mediate key functions in adaptive immunity. In a classical view, MHC-I molecules present peptides from intracellular source proteins, whereas MHC-II molecules present antigenic peptides from exogenous and membrane proteins. Nevertheless, substantial crosstalk between these two pathways has been observed. We investigated the influence of autophagy on the MHC-II ligandome and demonstrated that peptide presentation is altered considerably upon induction of autophagy. The presentation of peptides from intracellular and lysosomal source proteins was strongly increased on MHC-II in contrast with peptides from membrane and secreted proteins. In addition, autophagy influenced the MHC-II antigen-processing machinery. Our study illustrates a profound influence of autophagy on the class II peptide repertoire and suggests that this finding has implications for the regulation of CD4(+) T cell-mediated processes.
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Affiliation(s)
- Jörn Dengjel
- Department of Immunology, Institute for Cell Biology, University of Tübingen, 72076 Tübingen, Germany
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21
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Abstract
Major histocompatibility (MHC) class II molecules function to present antigenic peptides to CD4 T lymphocytes. The pathways by which these molecules present exogenous antigens have been extensively studied. However by contrast, far less is known about the processing and trafficking of cytosolic antigens, which can also serve as an alternative source of ligands for MHC class II molecules. Self-proteins, tumor antigens, as well as viral proteins found within the cytosol of cells, can be presented via MHC class II molecules, resulting in the activation of specific CD4 T cells. Studies have begun to reveal unique steps as well as some similarities in the pathways for cytosolic and exogenous antigen presentation. Recent developments in this area are summarized here.
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Affiliation(s)
- Delu Zhou
- Department of Microbiology and Immunology and Walther Oncology Center, Indiana University School of Medicine, and Walther Cancer Institute, Indianapolis, IN 46202, USA
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22
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Abstract
The conversion of exogenous and endogenous proteins into immunogenic peptides recognized by T lymphocytes involves a series of proteolytic and other enzymatic events culminating in the formation of peptides bound to MHC class I or class II molecules. Although the biochemistry of these events has been studied in detail, only in the past few years has similar information begun to emerge describing the cellular context in which these events take place. This review thus concentrates on the properties of antigen-presenting cells, especially those aspects of their overall organization, regulation, and intracellular transport that both facilitate and modulate the processing of protein antigens. Emphasis is placed on dendritic cells and the specializations that help account for their marked efficiency at antigen processing and presentation both in vitro and, importantly, in vivo. How dendritic cells handle antigens is likely to be as important a determinant of immunogenicity and tolerance as is the nature of the antigens themselves.
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Affiliation(s)
- E Sergio Trombetta
- Department of Cell Biology and Section of Immunobiology, Ludwig Institute for Cancer Research, Yale University School of Medicine, New Haven, Connecticut 06520-8002, USA.
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23
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Hanna J, Gonen-Gross T, Fitchett J, Rowe T, Daniels M, Arnon TI, Gazit R, Joseph A, Schjetne KW, Steinle A, Porgador A, Mevorach D, Goldman-Wohl D, Yagel S, LaBarre MJ, Buckner JH, Mandelboim O. Novel APC-like properties of human NK cells directly regulate T cell activation. J Clin Invest 2004; 114:1612-23. [PMID: 15578093 PMCID: PMC529284 DOI: 10.1172/jci22787] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2004] [Accepted: 09/21/2004] [Indexed: 11/17/2022] Open
Abstract
Initiation of the adaptive immune response is dependent on the priming of naive T cells by APCs. Proteomic analysis of unactivated and activated human NK cell membrane-enriched fractions demonstrated that activated NK cells can efficiently stimulate T cells, since they upregulate MHC class II molecules and multiple ligands for TCR costimulatory molecules. Furthermore, by manipulating antigen administration, we show that NK cells possess multiple independent unique pathways for antigen uptake. These results highlight NK cell-mediated cytotoxicity and specific ligand recognition by cell surface-activating receptors on NK cells as unique mechanisms for antigen capturing and presentation. In addition, we analyzed the T cell-activating potential of human NK cells derived from different clinical conditions, such as inflamed tonsils and noninfected and CMV-infected uterine decidual samples, and from transporter-associated processing antigen 2-deficient patients. This in vivo analysis revealed that proinflammatory, but not immune-suppressive, microenvironmental requirements can selectively dictate upregulation of T cell-activating molecules on NK cells. Taken together, these observations offer new and unexpected insights into the direct interactions between NK and T cells and suggest novel APC-like activating functions for human NK cells.
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Affiliation(s)
- Jacob Hanna
- The Lautenberg Center for General and Tumor Immunology, Hebrew University-Hadassah Medical School, Jerusalem, Israel
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24
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Díaz G, Cañas B, Vazquez J, Nombela C, Arroyo J. Characterization of natural peptide ligands from HLA-DP2: new insights into HLA-DP peptide-binding motifs. Immunogenetics 2004; 56:754-9. [PMID: 15565337 DOI: 10.1007/s00251-004-0735-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2004] [Revised: 10/14/2004] [Indexed: 10/26/2022]
Abstract
Although natural peptide ligands of HLA-DR and HLA-DQ molecules have been extensively studied, information about peptides naturally bound to HLA-DP is limited. Here we describe HLA-DP2 peptide ligands corresponding to 24 different source proteins that were identified by peptide pool elution and mass spectrometry sequencing from HLA-DP2 molecules expressed on EBV-LCLs. Sequencing analysis led to the identification of both promiscuous and allele-specific peptides. Moreover, the alignment of the natural ligands for HLA-DP2 described here, combined with previous results from our group and others concerning HLA-DP2 antigen presentation and HLA-DP molecular modelling, provide a better understanding of HLA-DP2 peptide-binding motifs.
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Affiliation(s)
- Gema Díaz
- Departamento de Microbiología II, Facultad de Farmacia, Universidad Complutense de Madrid, 28040, Madrid, Spain
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25
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Muntasell A, Carrascal M, Alvarez I, Serradell L, van Veelen P, Verreck FAW, Koning F, Abian J, Jaraquemada D. Dissection of the HLA-DR4 peptide repertoire in endocrine epithelial cells: strong influence of invariant chain and HLA-DM expression on the nature of ligands. THE JOURNAL OF IMMUNOLOGY 2004; 173:1085-93. [PMID: 15240697 DOI: 10.4049/jimmunol.173.2.1085] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Class II MHC (MHC II) expression is restricted to professional APCs and thymic epithelium but it also occurs in the epithelial cells of autoimmune organs which are the unique targets of the CD4 autoreactive T cells in endocrine autoimmune diseases. This specificity is presumably conditioned by an epithelium-specific peptide repertoire associated to MHC II at the cell surface. MHC II expression and function is dependent on the action of two main chaperones, invariant chain (Ii) and DM, whose expression is coregulated with MHC II. However, there is limited information about the in vivo expression levels of these molecules and uncoordinated expression has been demonstrated in class II-positive epithelial cells that may influence the MHC-associated peptide repertoires and the outcome of the autoimmune response. We have examined the pool of peptides associated to DR4 molecules expressed by a neuroendocrine epithelial cell and the consequences of Ii and DM coexpression. The RINm5F rat insulinoma cell line was transfected with HLA-DRB1*0401, Ii, and DM molecules in four different combinations: RIN-DR4, -DR4Ii, -DR4DM, and -DR4IiDM. The analysis of the peptide repertoire and the identification of the DR4 naturally processed ligands in each transfected cell were achieved by mass spectrometry. The results demonstrate that 1) the expression of Ii and DM affected the DR4 peptide repertoires by producing important variations in their content and in the origin of peptides; 2) these restrictions affected the stability and sequence of the peptides of each repertoire; and 3) Ii and DM had both independent and coordinate effects on these repertoires.
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Affiliation(s)
- Aura Muntasell
- Immunology Unit and Institute of Biotechnology and Biomedicine (IBB), Universitat Autònoma de Barcelona, Campus de Bellaterra, Barcelona, Spain
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