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Alvarez-Navarro C, López de Castro JA. ERAP1 structure, function and pathogenetic role in ankylosing spondylitis and other MHC-associated diseases. Mol Immunol 2013; 57:12-21. [PMID: 23916068 DOI: 10.1016/j.molimm.2013.06.012] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Revised: 06/18/2013] [Accepted: 06/18/2013] [Indexed: 10/26/2022]
Abstract
The endoplasmic reticulum aminopeptidase 1 (ERAP1) is a multifunctional enzyme involved in the final processing of Major Histocompatibility Complex class I (MHC-I) ligands and with a significant influence in the stability and immunological properties of MHC-I proteins. ERAP1 polymorphism is associated with ankylosing spondylitis among HLA-B27-positive individuals and the altered enzymatic activity of natural variants has significant effects on the HLA-B27 peptidome, suggesting a critical pathogenetic role of peptides in this disease. Likewise, the association of ERAP1 with other MHC-I associated disorders and its epistasis with their susceptibility MHC alleles point out to a general role of the MHC-I peptidome in these diseases. The functional interaction between ERAP1 and HLA-B27 or other MHC-I molecules may be related to the processing of specific epitopes, or to a more general peptide-dependent influence on other biological features of the MHC-I proteins. In addition, from a consideration of the reported functions of ERAP1, including its involvement in angiogenesis and macrophage activation, a more complex and multi-level influence in the inflammatory and immune pathways operating in these diseases cannot be ruled out.
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Affiliation(s)
- Carlos Alvarez-Navarro
- Centro de Biología Molecular Severo Ochoa (Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid), Madrid, Spain
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52
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Cinar M, Akar H, Yilmaz S, Simsek I, Karkucak M, Sagkan RI, Pekel A, Erdem H, Avci IY, Acikel C, Musabak U, Tunca Y, Pay S. A polymorphism in ERAP1 is associated with susceptibility to ankylosing spondylitis in a Turkish population. Rheumatol Int 2013; 33:2851-8. [PMID: 23864143 DOI: 10.1007/s00296-013-2824-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2013] [Accepted: 07/05/2013] [Indexed: 12/17/2022]
Abstract
We assessed the role played by the ERAP1 gene in Turkish patients with ankylosing spondylitis (AS) in terms of disease susceptibility, clinical manifestations, and disease severity. We included 150 consecutive AS patients who met the modified New York classification criteria and 150 healthy controls. We documented the presence of 10 ERAP1 single-nucleotide polymorphisms (SNPs) and HLA-B27 in these patients. ERAP1 SNPs were genotyped using competitive allele-specific polymerase chain reaction. Differences between genotype and allele frequencies were compared using the Pearson's Chi-square test. The associations between ERAP1 SNPs, on the one hand, and with disease severity and clinical findings, on the other, were determined. One SNP, rs26653, was significantly associated with AS susceptibility (OR 1.609, 95% CI 1.163-2.226; p = 0.004). The population-attributable risk of possession of the rs26653 SNP allele was 23.4%. No relationship was noted between HLA-B27 positivity and the distribution of rs26653 genotype frequency. No associations were seen between disease severity measures and clinical manifestations of AS. In summary, an ERAP1 polymorphism was associated with AS in a Turkish population. The contributions of HLA-B27 and the rs26653 SNP to AS pathogenesis appear to be independent.
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Affiliation(s)
- Muhammet Cinar
- Division of Rheumatology, Gulhane Military Medical Academy School of Medicine, Gn.Tevfik Sağlam Cad., 06018, Etlik, Ankara, Turkey,
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53
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Leone P, Shin EC, Perosa F, Vacca A, Dammacco F, Racanelli V. MHC class I antigen processing and presenting machinery: organization, function, and defects in tumor cells. J Natl Cancer Inst 2013; 105:1172-87. [PMID: 23852952 DOI: 10.1093/jnci/djt184] [Citation(s) in RCA: 369] [Impact Index Per Article: 33.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The surface presentation of peptides by major histocompatibility complex (MHC) class I molecules is critical to all CD8(+) T-cell adaptive immune responses, including those against tumors. The generation of peptides and their loading on MHC class I molecules is a multistep process involving multiple molecular species that constitute the so-called antigen processing and presenting machinery (APM). The majority of class I peptides begin as proteasome degradation products of cytosolic proteins. Once transported into the endoplasmic reticulum by TAP (transporter associated with antigen processing), peptides are not bound randomly by class I molecules but are chosen by length and sequence, with peptidases editing the raw peptide pool. Aberrations in APM genes and proteins have frequently been observed in human tumors and found to correlate with relevant clinical variables, including tumor grade, tumor stage, disease recurrence, and survival. These findings support the idea that APM defects are immune escape mechanisms that disrupt the tumor cells' ability to be recognized and killed by tumor antigen-specific cytotoxic CD8(+) T cells. Detailed knowledge of APM is crucial for the optimization of T cell-based immunotherapy protocols.
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Affiliation(s)
- Patrizia Leone
- Department of Internal Medicine and Clinical Oncology, University of Bari Medical School, Bari, Italy
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54
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Stratikos E, Stern LJ. Antigenic peptide trimming by ER aminopeptidases--insights from structural studies. Mol Immunol 2013; 55:212-9. [PMID: 23545452 DOI: 10.1016/j.molimm.2013.03.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2013] [Revised: 02/27/2013] [Accepted: 03/04/2013] [Indexed: 02/05/2023]
Abstract
Generation and destruction of antigenic peptides by ER resident aminopeptidases ERAP1 and ERAP2 have been shown in the last few years to be important for the correct functioning and regulation of the adaptive immune response. These two highly homologous aminopeptidases appear to have evolved complex mechanisms well suited for their biological role in antigen presentation. Furthermore, polymorphic variability in these enzymes appears to affect their function and predispose individuals to disease. This review discusses our current understanding of the molecular mechanisms behind ERAP1/2 function as suggested by several recently determined crystallographic structures of these enzymes.
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55
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Spencer CT, Dragovic SM, Conant SB, Gray JJ, Zheng M, Samir P, Niu X, Moutaftsi M, Van Kaer L, Sette A, Link AJ, Joyce S. Sculpting MHC class II-restricted self and non-self peptidome by the class I Ag-processing machinery and its impact on Th-cell responses. Eur J Immunol 2013; 43:1162-72. [PMID: 23386199 DOI: 10.1002/eji.201243087] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2012] [Revised: 01/02/2013] [Accepted: 01/30/2013] [Indexed: 01/14/2023]
Abstract
It is generally assumed that the MHC class I antigen (Ag)-processing (CAP) machinery - which supplies peptides for presentation by class I molecules - plays no role in class II-restricted presentation of cytoplasmic Ags. In striking contrast to this assumption, we previously reported that proteasome inhibition, TAP deficiency or ERAAP deficiency led to dramatically altered T helper (Th)-cell responses to allograft (HY) and microbial (Listeria monocytogenes) Ags. Herein, we tested whether altered Ag processing and presentation, altered CD4(+) T-cell repertoire, or both underlay the above finding. We found that TAP deficiency and ERAAP deficiency dramatically altered the quality of class II-associated self peptides suggesting that the CAP machinery impacts class II-restricted Ag processing and presentation. Consistent with altered self peptidomes, the CD4(+) T-cell receptor repertoire of mice deficient in the CAP machinery substantially differed from that of WT animals resulting in altered CD4(+) T-cell Ag recognition patterns. These data suggest that TAP and ERAAP sculpt the class II-restricted peptidome, impacting the CD4(+) T-cell repertoire, and ultimately altering Th-cell responses. Together with our previous findings, these data suggest multiple CAP machinery components sequester or degrade MHC class II-restricted epitopes that would otherwise be capable of eliciting functional Th-cell responses.
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Affiliation(s)
- Charles T Spencer
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, USA.
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56
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Barteneva NS, Ketman K, Fasler-Kan E, Potashnikova D, Vorobjev IA. Cell sorting in cancer research--diminishing degree of cell heterogeneity. Biochim Biophys Acta Rev Cancer 2013; 1836:105-22. [PMID: 23481260 DOI: 10.1016/j.bbcan.2013.02.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Revised: 02/06/2013] [Accepted: 02/08/2013] [Indexed: 12/18/2022]
Abstract
Increasing evidence of intratumor heterogeneity and its augmentation due to selective pressure of microenvironment and recent achievements in cancer therapeutics lead to the need to investigate and track the tumor subclonal structure. Cell sorting of heterogeneous subpopulations of tumor and tumor-associated cells has been a long established strategy in cancer research. Advancement in lasers, computer technology and optics has led to a new generation of flow cytometers and cell sorters capable of high-speed processing of single cell suspensions. Over the last several years cell sorting was used in combination with molecular biological methods, imaging and proteomics to characterize primary and metastatic cancer cell populations, minimal residual disease and single tumor cells. It was the principal method for identification and characterization of cancer stem cells. Analysis of single cancer cells may improve early detection of tumors, monitoring of circulating tumor cells, evaluation of intratumor heterogeneity and chemotherapeutic treatments. The aim of this review is to provide an overview of major cell sorting applications and approaches with new prospective developments such as microfluidics and microchip technologies.
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Affiliation(s)
- Natasha S Barteneva
- Program in Cellular and Molecular Medicine, Children's Hospital Boston, Harvard Medical School, Boston, MA, USA.
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57
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van Esch EMG, Welters MJP, Jordanova ES, Trimbos JBMZ, van der Burg SH, van Poelgeest MIE. Treatment failure in patients with HPV 16-induced vulvar intraepithelial neoplasia: understanding different clinical responses to immunotherapy. Expert Rev Vaccines 2012; 11:821-40. [PMID: 22913259 DOI: 10.1586/erv.12.56] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Failure of the immune system to launch a strong and effective immune response to high-risk HPV is related to viral persistence and the development of anogenital (pre)malignant lesions such as vulvar intraepithelial neoplasia (VIN). Different forms of immunotherapy, aimed at overcoming the inertia of the immune system, have been developed and met with clinical success. Unfortunately these, in principal successful, therapeutic approaches also fail to induce clinical responses in a substantial number of cases. In this review, the authors summarize the traits of the immune response to HPV in healthy individuals and in patients with HPV-induced neoplasia. The potential mechanisms involved in the escape of HPV-induced lesions from the immune system indicate gaps in our knowledge. Finally, the interaction between the immune system and VIN is discussed with a special focus on the different forms of immunotherapy applied to treat VIN and the potential causes of therapy failure. The authors conclude that there are a number of pre-existing conditions that determine the patients' responsiveness to immunotherapy. An immunotherapeutic strategy in which different aspects of immune failure are attacked by complementary approaches, will improve the clinical response rate.
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Affiliation(s)
- Edith M G van Esch
- Department of Gynecology, Leiden University Medical Center, PO Box 9600, 2300 RC, Leiden, The Netherlands
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58
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Peptidases trimming MHC class I ligands. Curr Opin Immunol 2012; 25:90-6. [PMID: 23089230 DOI: 10.1016/j.coi.2012.10.001] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Accepted: 10/03/2012] [Indexed: 12/29/2022]
Abstract
Peptides presented by MHC class I molecules are typically produced through antigen degradation by the proteasome followed by trimming by exopeptidases. According to recent results, these include both aminopeptidases and carboxypeptidases in the cytosol and the endoplasmic reticulum. While cytosolic peptidases have a net neutral or destructive effect on MHC ligands, endoplasmic reticulum aminopeptidases are required for efficient class I loading and have a strong effect on the repertoire of peptide/MHC complexes. Cells lacking these enzymes can be eliminated both by NK cells and by CD8+ T cells recognizing complexes formed between an MHC class Ib molecule and a conserved peptide. Cross-presented peptides derived from internalized antigens can be processed by insulin-regulated aminopeptidase, the only endosomal trimming peptidase.
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Genetic association with ERAP1 in psoriasis is confined to disease onset after puberty and not dependent on HLA-C*06. J Invest Dermatol 2012; 133:411-7. [PMID: 22931917 PMCID: PMC3547223 DOI: 10.1038/jid.2012.280] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
HLA-C remains the strongest susceptibility candidate gene in psoriasis. Evidence for interaction between HLA-C and endoplasmic reticulum aminopeptidase 1 (ERAP1) confined to individuals carrying the HLA-C risk allele was recently reported. Psoriasis displays wide variation, and genetic heterogeneity is likely to contribute to clinical diversity. Age at disease onset is a putative discriminator, and separating psoriasis into early- (<40 years) and late-onset disease has been useful. To sharpen the age-dependent phenotype, we compared genotypes for ERAP1 (rs26653, rs30187, and rs27524) and HLA-C*06:02 in healthy controls and cases stratified for onset of psoriasis at <10, 10-20, 20-40, and >40 years of age. This approach revealed that association with ERAP1 was confined to cases with onset between 10 and 20 years (odds ratio 1.59, 95% confidence interval: 1.28-1.98, P=0.00008) and no association was detected in cases with onset below 10 years, reflecting genetic heterogeneity within the childhood psoriasis population. In contrast to earlier findings, association with ERAP1 was neither dependent on nor interacting with HLA-C*06:02. ERAP1 single-nucleotide polymorphism rs26653, which, to our knowledge, has not previously been reported in psoriasis, is nonsynonymous, has suggestive functional consequences, and herein displays strong association with disease.
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60
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Cifaldi L, Romania P, Lorenzi S, Locatelli F, Fruci D. Role of endoplasmic reticulum aminopeptidases in health and disease: from infection to cancer. Int J Mol Sci 2012; 13:8338-8352. [PMID: 22942706 PMCID: PMC3430237 DOI: 10.3390/ijms13078338] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2012] [Revised: 06/27/2012] [Accepted: 06/29/2012] [Indexed: 12/22/2022] Open
Abstract
Endoplasmic reticulum (ER) aminopeptidases ERAP1 and ERAP2 (ERAPs) are essential for the maturation of a wide spectrum of proteins involved in various biological processes. In the ER, these enzymes work in concert to trim peptides for presentation on MHC class I molecules. Loss of ERAPs function substantially alters the repertoire of peptides presented by MHC class I molecules, critically affecting recognition of both NK and CD8+ T cells. In addition, these enzymes are involved in the modulation of inflammatory responses by promoting the shedding of several cytokine receptors, and in the regulation of both blood pressure and angiogenesis. Recent genome-wide association studies have identified common variants of ERAP1 and ERAP2 linked to several human diseases, ranging from viral infections to autoimmunity and cancer. More recently, inhibition of ER peptide trimming has been shown to play a key role in stimulating innate and adaptive anti-tumor immune responses, suggesting that inhibition of ERAPs might be exploited for the establishment of innovative therapeutic approaches against cancer. This review summarizes data currently available for ERAP enzymes in ER peptide trimming and in other immunological and non-immunological functions, paying attention to the emerging role played by these enzymes in human diseases.
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Affiliation(s)
- Loredana Cifaldi
- Paediatric Haematology/Oncology Department, Bambino Gesù Children’s Hospital IRCCS, Piazza S. Onofrio 4, Rome 00165, Italy; E-Mails: (L.C.); (P.R.); (S.L.); (F.L.)
| | - Paolo Romania
- Paediatric Haematology/Oncology Department, Bambino Gesù Children’s Hospital IRCCS, Piazza S. Onofrio 4, Rome 00165, Italy; E-Mails: (L.C.); (P.R.); (S.L.); (F.L.)
| | - Silvia Lorenzi
- Paediatric Haematology/Oncology Department, Bambino Gesù Children’s Hospital IRCCS, Piazza S. Onofrio 4, Rome 00165, Italy; E-Mails: (L.C.); (P.R.); (S.L.); (F.L.)
| | - Franco Locatelli
- Paediatric Haematology/Oncology Department, Bambino Gesù Children’s Hospital IRCCS, Piazza S. Onofrio 4, Rome 00165, Italy; E-Mails: (L.C.); (P.R.); (S.L.); (F.L.)
- University of Pavia, Corso Strada Nuova 65, Pavia I-27100, Italy
| | - Doriana Fruci
- Paediatric Haematology/Oncology Department, Bambino Gesù Children’s Hospital IRCCS, Piazza S. Onofrio 4, Rome 00165, Italy; E-Mails: (L.C.); (P.R.); (S.L.); (F.L.)
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +39-6-68592657; Fax: +39-6-68592904
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Diaz-Padilla I, Amir E, Marsh S, Liu G, Mackay H. Genetic polymorphisms as predictive and prognostic biomarkers in gynecological cancers: a systematic review. Gynecol Oncol 2011; 124:354-65. [PMID: 22063461 DOI: 10.1016/j.ygyno.2011.10.034] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2011] [Revised: 10/28/2011] [Accepted: 10/29/2011] [Indexed: 11/15/2022]
Abstract
PURPOSE Numerous studies have explored the potential role of genetic polymorphisms as predictive or prognostic biomarkers in gynecologic malignancies. A systematic review for all eligible polymorphisms has not yet been reported. The aim of this study was to summarize the current status of the field and provide direction for future research. DESIGN We searched literature databases (MEDLINE, EMBASE, Cochrane) from 2006 to April 2011 to identify studies evaluating the association between gene polymorphisms and clinical outcome in ovarian, endometrial, cervical, or vulvar cancer. The main outcome measures were overall survival (OS) and progression-free survival (PFS). Studies reporting relationships between polymorphisms and toxicity were also included. RESULTS Sixty two studies met the inclusion criteria. The median sample size was 140. Most of the included studies (n=50, 81%) were conducted in ovarian cancer patients. Almost a third assessed potential predictive associations between gene polymorphism and outcome in ovarian cancer. The most commonly evaluated genes were ERCC1, VEGF, ABCB1 (MDR), and GSTP1. Most studies (n=44, 71%) were observational case-series. Only four studies (6%) included a validation arm and patient population ethnicity was explicitly stated only in 27% of included studies. CONCLUSION No consistent association between any gene polymorphism and clinical outcome in gynecological cancers has been found across studies. There is incomplete adherence to the REMARK guidelines and inadequate methodology reporting in most studies. Moving forward, analysis of large trial-based clinical samples; adherence to the highest methodological standards, and focus on validation analyses are necessary to identify clinically useful pharmacogenomic biomarkers of outcome.
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Affiliation(s)
- Ivan Diaz-Padilla
- Division of Medical Oncology, Princess Margaret Hospital, University of Toronto, Ontario, Canada.
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62
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Szczypiorska M, Sánchez A, Bartolomé N, Arteta D, Sanz J, Brito E, Fernández P, Collantes E, Martínez A, Tejedor D, Artieda M, Mulero J. ERAP1 polymorphisms and haplotypes are associated with ankylosing spondylitis susceptibility and functional severity in a Spanish population. Rheumatology (Oxford) 2011; 50:1969-75. [PMID: 21865284 DOI: 10.1093/rheumatology/ker229] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVES The aim of this study was to assess the involvement of the endoplasmic reticulum aminopeptidase 1 (ERAP1) gene in AS susceptibility and functional severity in a Spanish population. METHODS Eight single nucleotide polymorphisms (SNPs) spanning the ERAP1 gene were genotyped by allele-specific fluorescent PCR in 300 AS Spanish patients and 300 spondylarthritis-free controls. The influence of the ERAP1 SNPs on the functional severity of AS was analysed with the BASFI corrected for disease duration. Association analyses with AS susceptibility and functional severity were performed. RESULTS Significant ERAP1 single marker association with AS susceptibility was found for five SNPs, namely rs30187 (allele T: P = 0.035), rs17482078 (allele C: P = 0.030), rs2287987 (allele T: P = 0.028), rs26653 (allele C: P = 0.041) and rs10050860 (allele C: P = 0.018). Three of the associated SNPs (rs17482078, rs2287987 and rs10050860) were in strong linkage disequilibrium. After imputing genotypes with the HapMap CEU data as reference, the strongest association was with rs41135 (P = 0.0046) in the 5'-upstream region of ERAP1. In addition, the SNP rs17481856 was found to be a risk factor for functional severity in AS and a borderline trend was observed for rs27044. CONCLUSIONS These results suggest that the ERAP1 gene is associated with genetic predisposition to AS and influences the functional severity of the disease in a Spanish population.
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63
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van Endert P. Post-proteasomal and proteasome-independent generation of MHC class I ligands. Cell Mol Life Sci 2011; 68:1553-67. [PMID: 21390545 PMCID: PMC11115176 DOI: 10.1007/s00018-011-0662-1] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [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: 12/18/2022]
Abstract
Peptide ligands presented by MHC class I molecules are produced by intracellular proteolysis, which often involves multiple steps. Initial antigen degradation seems to rely almost invariably on the proteasome, although tripeptidyl peptidase II (TPP II) and insulin-degrading enzyme (IDE) may be able to substitute for the proteasome in rare cases. Recent evidence suggests that the net effect of cytosolic aminopeptidases is destruction of potential class I ligands, although a positive role in selected cases has been documented. This may apply particularly to the trimming of long precursors by TPP II. In contrast, trimming of ligand precursors in the endoplasmic reticulum is essential for the generation of suitable peptides and has a substantial impact on the repertoire of ligands presented. Trimming by the ER aminopeptidase (ERAP) enzymes most likely acts on free precursors and is adapted to the needs of class I molecules by way of a molecular ruler mechanism. Trimming by ERAP enzymes also occurs for cross-presented ligands, which can alternatively be processed in a special endosomal compartment by insulin-regulated aminopeptidase.
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Affiliation(s)
- Peter van Endert
- Institut National de la Santé et de la Recherche Médicale, Unité 1013, Paris 75015, France.
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64
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Goto Y, Ogawa K, Hattori A, Tsujimoto M. Secretion of endoplasmic reticulum aminopeptidase 1 is involved in the activation of macrophages induced by lipopolysaccharide and interferon-gamma. J Biol Chem 2011; 286:21906-14. [PMID: 21531727 DOI: 10.1074/jbc.m111.239111] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Endoplasmic reticulum aminopeptidase 1 (ERAP1) is a multifunctional enzyme with an important role in processing antigenic peptides presented to class I major histocompatibility complex in the endoplasmic reticulum. In this study, we found that endoplasmic reticulum-retained ERAP1 was secreted from macrophages in response to activation by treatment with lipopolysaccharide (LPS) and interferon (IFN)-γ and enhanced their phagocytic activity. Enhancement of the phagocytic activity of murine macrophage RAW264.7 cells induced by LPS/IFN-γ was inhibited by a potent aminopeptidase inhibitor, amastatin. The addition of recombinant wild-type but not inactive mutant ERAP1 to culture medium enhanced phagocytosis. These results suggest that enhancement of phagocytic activity is at least in part mediated by secreted ERAP1 through the generation of active peptides processed by the enzyme. Our data reveal ERAP1-mediated activation of macrophages for the first time and will provide new insights into the role of this enzyme in innate immunity.
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Affiliation(s)
- Yoshikuni Goto
- Laboratory of Cellular Biochemistry, RIKEN, Wako, Saitama, 351-0198, Japan
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65
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Structural basis for antigenic peptide precursor processing by the endoplasmic reticulum aminopeptidase ERAP1. Nat Struct Mol Biol 2011; 18:604-13. [PMID: 21478864 PMCID: PMC3087843 DOI: 10.1038/nsmb.2021] [Citation(s) in RCA: 156] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2010] [Accepted: 01/26/2011] [Indexed: 02/07/2023]
Abstract
ERAP1 trims antigen precursors to fit into MHC class I proteins. To perform this function, ERAP1 has unique substrate preferences, trimming long peptides while sparing shorter ones. To identify the structural basis for ERAP1's unusual properties, we determined the X-ray crystal structure of human ERAP1 bound to bestatin. The structure reveals an open conformation with a large interior compartment. An extended groove originating from the enzyme's catalytic center can accommodate long peptides and has features that explain ERAP1's broad specificity for antigenic peptide precursors. Structural and biochemical analysis suggest a mechanism for ERAP1's length-dependent trimming activity, whereby binding of long but not short substrates induces a conformational change with reorientation of a key catalytic residue towards the active site. ERAP1's unique structural elements suggest how a generic aminopeptidase structure has been adapted for the specialized function of trimming antigenic precursors.
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66
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Brown MA. Genetics of ankylosing spondylitis. Rheumatology (Oxford) 2011. [DOI: 10.1016/b978-0-323-06551-1.00114-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
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67
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Abstract
This article summarizes the proceedings of a one-day international workshop held in July 2009 on the role of HLA-B27 in the pathogenesis of ankylosing spondylitis (AS) and related disorders. HLA-B27 is found in about 90% of patients with AS, with an odds ratio of about 100, but the mechanism underlying this association is not known. There are currently 3 major mechanistic hypotheses for this association: (1) T cell recognition of one or more B27 presented peptides; (2) B27 heavy-chain misfolding that induces an unfolded protein response; and (3) innate immune recognition of cell-surface expressed B27 heavy-chain dimers. None of these hypotheses accounts for the tissue specificity of the inflammation characteristic of AS. These hypotheses were discussed in the context of known epidemiologic, biochemical, structural, and immunologic differences among HLA-B27 subtypes; data from the HLA-B27 transgenic rat model of spondyloarthritis; the growing list of other genes that have been found to be associated with AS; and other data on the pathogenesis of spondyloarthritis. Proposed directions for future research include expanded efforts to define similarities and differences among the B27 subtypes; further development of animal models; identifying the interactions of B27 with the products of other genes associated with AS; and continued investigation into the pathogenesis of spondyloarthritis.
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68
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Andrés AM, Dennis MY, Kretzschmar WW, Cannons JL, Lee-Lin SQ, Hurle B, Schwartzberg PL, Williamson SH, Bustamante CD, Nielsen R, Clark AG, Green ED. Balancing selection maintains a form of ERAP2 that undergoes nonsense-mediated decay and affects antigen presentation. PLoS Genet 2010; 6:e1001157. [PMID: 20976248 PMCID: PMC2954825 DOI: 10.1371/journal.pgen.1001157] [Citation(s) in RCA: 179] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2010] [Accepted: 09/13/2010] [Indexed: 11/18/2022] Open
Abstract
A remarkable characteristic of the human major histocompatibility complex (MHC) is its extreme genetic diversity, which is maintained by balancing selection. In fact, the MHC complex remains one of the best-known examples of natural selection in humans, with well-established genetic signatures and biological mechanisms for the action of selection. Here, we present genetic and functional evidence that another gene with a fundamental role in MHC class I presentation, endoplasmic reticulum aminopeptidase 2 (ERAP2), has also evolved under balancing selection and contains a variant that affects antigen presentation. Specifically, genetic analyses of six human populations revealed strong and consistent signatures of balancing selection affecting ERAP2. This selection maintains two highly differentiated haplotypes (Haplotype A and Haplotype B), with frequencies 0.44 and 0.56, respectively. We found that ERAP2 expressed from Haplotype B undergoes differential splicing and encodes a truncated protein, leading to nonsense-mediated decay of the mRNA. To investigate the consequences of ERAP2 deficiency on MHC presentation, we correlated surface MHC class I expression with ERAP2 genotypes in primary lymphocytes. Haplotype B homozygotes had lower levels of MHC class I expressed on the surface of B cells, suggesting that naturally occurring ERAP2 deficiency affects MHC presentation and immune response. Interestingly, an ERAP2 paralog, endoplasmic reticulum aminopeptidase 1 (ERAP1), also shows genetic signatures of balancing selection. Together, our findings link the genetic signatures of selection with an effect on splicing and a cellular phenotype. Although the precise selective pressure that maintains polymorphism is unknown, the demonstrated differences between the ERAP2 splice forms provide important insights into the potential mechanism for the action of selection. It has long been known that the extremely high levels of genetic diversity present in the major histocompatibility locus (MHC) are due to balancing selection, a type of natural selection that maintains advantageous genetic diversity in populations. The MHC encodes for molecules required for a type of antigen presentation that mediates detection of infected and cancerous cells by the immune system; the genetic diversity of the MHC thus ensures an adequate response to the wide variety of pathogens that humans encounter. Here, we show that other genes involved in the same antigen-presentation pathway are also subject to balancing selection in humans. Specifically, we show that balancing selection acts to maintain two forms of the endoplasmic reticulum aminopeptidase 2 gene (ERAP2), which encodes a protein also involved in antigen presentation. Although the two ERAP2 forms are present in a similar frequency (close to 0.5), they are associated with differences with respect to the levels of MHC molecules on the cell surface of immune cells. In summary, our findings show that natural selection maintains variants of ERAP2 that affect immune surveillance; they also establish ERAP2 as one of the few examples of balancing selection in humans where the selected variant, its functional consequences, and its influence in interpersonal diversity are known.
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Affiliation(s)
- Aida M Andrés
- Genome Technology Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, USA.
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Bukur J, Herrmann F, Handke D, Recktenwald C, Seliger B. Identification of E2F1 as an important transcription factor for the regulation of tapasin expression. J Biol Chem 2010; 285:30419-26. [PMID: 20663889 PMCID: PMC2945534 DOI: 10.1074/jbc.m109.094284] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2009] [Revised: 06/23/2010] [Indexed: 11/06/2022] Open
Abstract
HER-2/neu overexpression in tumor cells caused abnormalities of MHC class I surface expression due to impaired expression of components of the antigen-processing machinery (APM) including the low molecular weight proteins, the transporter associated with antigen processing (TAP), and the chaperone tapasin, whereas the expression of MHC class I heavy chain as well as β(2)-microglobulin was only marginally affected. This oncogene-mediated deficient APM component expression could be reverted by interferon-γ treatment, suggesting a deregulation rather than structural alterations as underlying molecular mechanisms. To determine the level of regulation, the transcriptional activity of APM components was analyzed in HER-2/neu(-) and HER-2/neu(+) cells. All major APM components were transcriptionally down-regulated in HER-2/neu(+) when compared with HER-2/neu(-) cells, which was accompanied by a reduced binding of RNA polymerase II to the APM promoters. Site-directed mutagenesis of the p300- and E2F-binding sites in the APM promoters did not reconstitute the oncogene-mediated decreased transcription rate with the exception of tapasin, which was restored in HER-2/neu(+) cells to levels of wild type tapasin promoter activity in HER-2/neu(-) fibroblasts. The E2F-directed control of tapasin expression was further confirmed by chromatin immunoprecipitation analyses showing that E2F1 and p300 bind to the tapasin and APM promoters in both cell lines. Moreover, siRNA-mediated silencing of E2F1 was associated with an increased tapasin expression, whereas transient overexpression of E2F1 launch a reduced tapasin transcription, suggesting that E2F1 is an essential transcription factor for tapasin.
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Affiliation(s)
- Juergen Bukur
- From the Institute of Medical Immunology, Martin Luther University Halle-Wittenberg, 06112 Halle (Saale), Germany
| | - Felix Herrmann
- From the Institute of Medical Immunology, Martin Luther University Halle-Wittenberg, 06112 Halle (Saale), Germany
| | - Diana Handke
- From the Institute of Medical Immunology, Martin Luther University Halle-Wittenberg, 06112 Halle (Saale), Germany
| | - Christian Recktenwald
- From the Institute of Medical Immunology, Martin Luther University Halle-Wittenberg, 06112 Halle (Saale), Germany
| | - Barbara Seliger
- From the Institute of Medical Immunology, Martin Luther University Halle-Wittenberg, 06112 Halle (Saale), Germany
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Kamphausen E, Kellert C, Abbas T, Akkad N, Tenzer S, Pawelec G, Schild H, van Endert P, Seliger B. Distinct molecular mechanisms leading to deficient expression of ER-resident aminopeptidases in melanoma. Cancer Immunol Immunother 2010; 59:1273-84. [PMID: 20419298 PMCID: PMC11030553 DOI: 10.1007/s00262-010-0856-7] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2009] [Accepted: 04/08/2010] [Indexed: 01/22/2023]
Abstract
Immune surveillance of tumour cells by CD8(+) cytotoxic T cells plays a key role in the establishment and control of an anti-tumour response. This process requires the generation of antigenic peptides, which are largely produced by the proteasome in combination with other proteases located in either the cytoplasm and/or the endoplasmic reticulum (ER). The ER-resident aminopeptidases ERAP1 and ERAP2 trim or even destroy HLA class I-binding peptides thereby shaping the peptide repertoire presented for T cell recognition. So far there exists limited information about the expression pattern of ERAP1 and/or ERAP2 in human tumours of distinct histotypes. Therefore, the expression profiles and modes of regulation of both aminopeptidases were determined in a large series of melanoma cell lines. A heterogeneous expression ranging from high to reduced or even total loss of ERAP1 and/or ERAP2 mRNA and/or protein expression was detected, which often could be induced/upregulated by interferon-gamma treatment. The observed altered ERAP1 and/or ERAP2 expression and activity levels were either mediated by sequence alterations affecting the promoter or enzymatic activities, leading to either transcriptional and/or post-transcriptional downregulation mechanisms or limited or excessive processing activities, which both might have an impact on the antigenic peptide repertoire presented on HLA class I molecules.
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Affiliation(s)
- Esther Kamphausen
- Institute of Medical Immunology, Martin-Luther-University Halle-Wittenberg, Magdeburger Str. 2, 06112 Halle (Saale), Germany
| | - Christiane Kellert
- Institute of Medical Immunology, Martin-Luther-University Halle-Wittenberg, Magdeburger Str. 2, 06112 Halle (Saale), Germany
| | - Tarish Abbas
- Institute of Medical Immunology, Martin-Luther-University Halle-Wittenberg, Magdeburger Str. 2, 06112 Halle (Saale), Germany
| | - Nadja Akkad
- Institute of Immunology, Johannes Gutenberg University, Obere Zahlbacherstraße 67, 55131 Mainz, Germany
| | - Stefan Tenzer
- Institute of Immunology, Johannes Gutenberg University, Obere Zahlbacherstraße 67, 55131 Mainz, Germany
| | - Graham Pawelec
- Section for Transplantation Immunology and Immunohaematology, 2nd Department of Internal Medicine, University of Tuebingen, Waldhoernlestr. 22, 72072 Tübingen, Germany
| | - Hansjoerg Schild
- Institute of Immunology, Johannes Gutenberg University, Obere Zahlbacherstraße 67, 55131 Mainz, Germany
| | - Peter van Endert
- INSERM, unité 580, 75015 Paris, France
- Faculté de Médicine René Descartes, Université Paris Descartes, 75015 Paris, France
| | - Barbara Seliger
- Institute of Medical Immunology, Martin-Luther-University Halle-Wittenberg, Magdeburger Str. 2, 06112 Halle (Saale), Germany
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Lowe AJ, Huh YS, Strickland AD, Erickson D, Batt CA. Multiplex Single Nucleotide Polymorphism Genotyping Utilizing Ligase Detection Reaction Coupled Surface Enhanced Raman Spectroscopy. Anal Chem 2010; 82:5810-4. [DOI: 10.1021/ac100921b] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Adam J. Lowe
- Graduate Field of Microbiology, Sibley School of Mechanical and Aerospace Engineering and Department of Food Science, Cornell University, Ithaca, New York 14853, and Division of Materials Science, Korea Basic Science Institute, Daejeon 305-333, Korea
| | - Yun Suk Huh
- Graduate Field of Microbiology, Sibley School of Mechanical and Aerospace Engineering and Department of Food Science, Cornell University, Ithaca, New York 14853, and Division of Materials Science, Korea Basic Science Institute, Daejeon 305-333, Korea
| | - Aaron D. Strickland
- Graduate Field of Microbiology, Sibley School of Mechanical and Aerospace Engineering and Department of Food Science, Cornell University, Ithaca, New York 14853, and Division of Materials Science, Korea Basic Science Institute, Daejeon 305-333, Korea
| | - David Erickson
- Graduate Field of Microbiology, Sibley School of Mechanical and Aerospace Engineering and Department of Food Science, Cornell University, Ithaca, New York 14853, and Division of Materials Science, Korea Basic Science Institute, Daejeon 305-333, Korea
| | - Carl A. Batt
- Graduate Field of Microbiology, Sibley School of Mechanical and Aerospace Engineering and Department of Food Science, Cornell University, Ithaca, New York 14853, and Division of Materials Science, Korea Basic Science Institute, Daejeon 305-333, Korea
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Brown MA. Progress in spondylarthritis. Progress in studies of the genetics of ankylosing spondylitis. Arthritis Res Ther 2009; 11:254. [PMID: 19886979 PMCID: PMC2787301 DOI: 10.1186/ar2692] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The advent of high-throughput SNP genotyping methods has advanced research into the genetics of common complex genetic diseases such as ankylosing spondylitis (AS) rapidly in recent times. The identification of associations with the genes IL23R and ERAP1 have been robustly replicated, and advances have been made in studies of the major histocompatibility complex genetics of AS, and of KIR gene variants and the disease. The findings are already being translated into increased understanding of the immunological pathways involved in AS, and raising novel potential therapies. The current studies in AS remain underpowered, and no full genomewide association study has yet been reported in AS; such studies are likely to add to the significant advances that have already been made.
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Affiliation(s)
- Matthew A Brown
- Diamantina Institute of Cancer, Immunology and Metabolic Medicine, University of Queensland, Princess Alexandra Hospital, Ipswich Road, Woolloongabba, Brisbane 4102, Australia.
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Abstract
PURPOSE OF REVIEW The field of genetic research in ankylosing spondylitis (AS) is advancing rapidly. The purpose of this review is to outline recent findings, particularly, in regard to genetic studies of the major histocompatibility complex (MHC) and the non-MHC genes IL23R, ERAP1, and killer cell immunologlobulin-like receptor (KIR) complex, in AS. RECENT FINDINGS Convincing evidence has been reported for the existence of further non-B27 MHC genes involved in AS. Strong, replicated association has been reported with IL23R and ERAP1 and AS. The IL23R finding strongly implicates the TH17 lymphocyte system in AS aetiopathogenesis. Suggestive evidence of a role for KIR gene polymorphism in AS exists, but definitive findings are awaited. SUMMARY The findings suggest that further genome-wide studies in large case-control cohorts are likely to be very productive in this disease. The IL23R findings and subsequent immunological investigations suggest that targeted intervention in the TH17 system is likely to have major therapeutic benefit, as it does in the genetically related diseases, inflammatory bowel disease and psoriasis.
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