1
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Boon L, Belmondo T, Vulsteke JB, Wuyts G, Derua R, Hüe S, Bossuyt X. Anti-Ki/anti-PA28γ autoantibodies contribute to the HEp-2 indirect immunofluorescence nuclear speckled pattern. Clin Chem Lab Med 2023; 61:435-441. [PMID: 36445291 DOI: 10.1515/cclm-2022-0858] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Accepted: 11/16/2022] [Indexed: 12/02/2022]
Abstract
OBJECTIVES Antinuclear antibodies (ANAs) are associated with several autoimmune diseases. Indirect immunofluorescence (IIF) on human epithelial type 2 (HEp-2) cells is the golden standard for ANA detection in the clinic. In case of a positive HEp-2 IIF test result, follow-up tests are done to determine autoantibody specificity. For a fraction of the HEp-2 IIF-positive samples, the nature of the autoantigens remains uncharacterized. Our objective was to characterize autoantigens in such samples. METHODS To characterize autoantigens in an unbiased way, we combined protein immunoprecipitation with liquid chromatography (LC) tandem mass spectrometry (MS/MS) sequencing. RESULTS Using such approach we detected the Ki antigen, also referred to as PA28γ, in the immunoprecipitate of serum samples of three individuals with an autoimmune disease. The HEp-2 nuclear speckled IIF fluorescent signal of all three serum samples was abolished after pre-absorption of the serum with recombinant Ki antigen, confirming that autoantibodies against Ki underlie the HEp-2 IIF signal. CONCLUSIONS Our data suggest that anti-Ki autoantibodies can underlie a nuclear speckled HEp-2 IIF pattern.
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Affiliation(s)
- Lise Boon
- Clinical and Diagnostic Immunology, Department of Microbiology, Immunology and Transplantation, KU Leuven, Leuven, Belgium
| | - Thibaut Belmondo
- Department of Laboratory Medicine, Henri Mondor Hospital, Créteil, France
| | - Jean-Baptiste Vulsteke
- Skeletal Biology and Engineering Research Center, Department of Development and Regeneration, KU Leuven, Leuven, Belgium.,Division of Rheumatology, University Hospitals Leuven, Leuven, Belgium
| | - Greet Wuyts
- Clinical and Diagnostic Immunology, Department of Microbiology, Immunology and Transplantation, KU Leuven, Leuven, Belgium
| | - Rita Derua
- Laboratory of Protein Phosphorylation and Proteomics, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
| | - Sophie Hüe
- Department of Laboratory Medicine, Henri Mondor Hospital, Créteil, France
| | - Xavier Bossuyt
- Clinical and Diagnostic Immunology, Department of Microbiology, Immunology and Transplantation, KU Leuven, Leuven, Belgium.,Department of Laboratory Medicine, University Hospitals Leuven, Leuven, Belgium
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2
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Gaun A, Preciado López M, Olsson N, Wang JCK, Chan LJG, O'Brien J, Li W, Zavala‐Solorio J, Zhang C, Eaton D, McAllister FE. Triple‐threat quantitative multiplexed plasma proteomics analysis on immune complex disease MRL‐lpr mice. Proteomics 2022; 22:e2100242. [DOI: 10.1002/pmic.202100242] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 06/30/2022] [Accepted: 07/22/2022] [Indexed: 11/07/2022]
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3
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Wang JY, Zhang W, Roehrl VB, Roehrl MW, Roehrl MH. An Autoantigen Atlas From Human Lung HFL1 Cells Offers Clues to Neurological and Diverse Autoimmune Manifestations of COVID-19. Front Immunol 2022; 13:831849. [PMID: 35401574 PMCID: PMC8987778 DOI: 10.3389/fimmu.2022.831849] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 02/21/2022] [Indexed: 12/27/2022] Open
Abstract
COVID-19 is accompanied by a myriad of both transient and long-lasting autoimmune responses. Dermatan sulfate (DS), a glycosaminoglycan crucial for wound healing, has unique affinity for autoantigens (autoAgs) from apoptotic cells. DS-autoAg complexes are capable of stimulating autoreactive B cells and autoantibody production. We used DS-affinity proteomics to define the autoantigen-ome of lung fibroblasts and bioinformatics analyses to study the relationship between autoantigenic proteins and COVID-induced alterations. Using DS-affinity, we identified an autoantigen-ome of 408 proteins from human HFL1 cells, at least 231 of which are known autoAgs. Comparing with available COVID data, 352 proteins of the autoantigen-ome have thus far been found to be altered at protein or RNA levels in SARS-CoV-2 infection, 210 of which are known autoAgs. The COVID-altered proteins are significantly associated with RNA metabolism, translation, vesicles and vesicle transport, cell death, supramolecular fibrils, cytoskeleton, extracellular matrix, and interleukin signaling. They offer clues to neurological problems, fibrosis, smooth muscle dysfunction, and thrombosis. In particular, 150 altered proteins are related to the nervous system, including axon, myelin sheath, neuron projection, neuronal cell body, and olfactory bulb. An association with the melanosome is also identified. The findings from our study illustrate a connection between COVID infection and autoimmunity. The vast number of COVID-altered proteins with high intrinsic propensity to become autoAgs offers an explanation for the diverse autoimmune complications in COVID patients. The variety of autoAgs related to mRNA metabolism, translation, and vesicles suggests a need for long-term monitoring of autoimmunity in COVID. The COVID autoantigen atlas we are establishing provides a detailed molecular map for further investigation of autoimmune sequelae of the pandemic, such as “long COVID” syndrome.
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Affiliation(s)
- Julia Y. Wang
- Curandis, New York, NY, United States
- *Correspondence: Julia Y. Wang, ; Michael H. Roehrl,
| | - Wei Zhang
- Department of Gastroenterology, Affiliated Hospital of Guizhou Medical University, Guiyang, China
| | | | | | - Michael H. Roehrl
- Department of Pathology and Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, United States
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY, United States
- *Correspondence: Julia Y. Wang, ; Michael H. Roehrl,
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4
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Role of Proteasomes in Inflammation. J Clin Med 2021; 10:jcm10081783. [PMID: 33923887 PMCID: PMC8072576 DOI: 10.3390/jcm10081783] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Revised: 04/10/2021] [Accepted: 04/14/2021] [Indexed: 12/14/2022] Open
Abstract
The ubiquitin–proteasome system (UPS) is involved in multiple cellular functions including the regulation of protein homeostasis, major histocompatibility (MHC) class I antigen processing, cell cycle proliferation and signaling. In humans, proteasome loss-of-function mutations result in autoinflammation dominated by a prominent type I interferon (IFN) gene signature. These genomic alterations typically cause the development of proteasome-associated autoinflammatory syndromes (PRAAS) by impairing proteasome activity and perturbing protein homeostasis. However, an abnormal increased proteasomal activity can also be found in other human inflammatory diseases. In this review, we cast a light on the different clinical aspects of proteasomal activity in human disease and summarize the currently studied therapeutic approaches.
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5
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Wang JY, Zhang W, Roehrl VB, Roehrl MW, Roehrl MH. An Autoantigen-ome from HS-Sultan B-Lymphoblasts Offers a Molecular Map for Investigating Autoimmune Sequelae of COVID-19. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2021:2021.04.05.438500. [PMID: 33851168 PMCID: PMC8043459 DOI: 10.1101/2021.04.05.438500] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
To understand how COVID-19 may induce autoimmune diseases, we have been compiling an atlas of COVID-autoantigens (autoAgs). Using dermatan sulfate (DS) affinity enrichment of autoantigenic proteins extracted from HS-Sultan lymphoblasts, we identified 362 DS-affinity proteins, of which at least 201 (56%) are confirmed autoAgs. Comparison with available multi-omic COVID data shows that 315 (87%) of the 362 proteins are affected in SARS-CoV-2 infection via altered expression, interaction with viral components, or modification by phosphorylation or ubiquitination, at least 186 (59%) of which are known autoAgs. These proteins are associated with gene expression, mRNA processing, mRNA splicing, translation, protein folding, vesicles, and chromosome organization. Numerous nuclear autoAgs were identified, including both classical ANAs and ENAs of systemic autoimmune diseases and unique autoAgs involved in the DNA replication fork, mitotic cell cycle, or telomerase maintenance. We also identified many uncommon autoAgs involved in nucleic acid and peptide biosynthesis and nucleocytoplasmic transport, such as aminoacyl-tRNA synthetases. In addition, this study found autoAgs that potentially interact with multiple SARS-CoV-2 Nsp and Orf components, including CCT/TriC chaperonin, insulin degrading enzyme, platelet-activating factor acetylhydrolase, and the ezrin-moesin-radixin family. Furthermore, B-cell-specific IgM-associated ER complex (including MBZ1, BiP, heat shock proteins, and protein disulfide-isomerases) is enriched by DS-affinity and up-regulated in B-cells of COVID-19 patients, and a similar IgH-associated ER complex was also identified in autoreactive pre-B1 cells in our previous study, which suggests a role of autoreactive B1 cells in COVID-19 that merits further investigation. In summary, this study demonstrates that virally infected cells are characterized by alterations of proteins with propensity to become autoAgs, thereby providing a possible explanation for infection-induced autoimmunity. The COVID autoantigen-ome provides a valuable molecular resource and map for investigation of COVID-related autoimmune sequelae and considerations for vaccine design.
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Affiliation(s)
| | - Wei Zhang
- Department of Gastroenterology, Affiliated Hospital of Guizhou Medical University, Guizhou, China
| | | | | | - Michael H. Roehrl
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, USA
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, USA
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6
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Wang JY, Zhang W, Roehrl MW, Roehrl VB, Roehrl MH. An Autoantigen Atlas from Human Lung HFL1 Cells Offers Clues to Neurological and Diverse Autoimmune Manifestations of COVID-19. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2021:2021.01.24.427965. [PMID: 33501444 PMCID: PMC7836114 DOI: 10.1101/2021.01.24.427965] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
COVID-19 is accompanied by a myriad of both transient and long-lasting autoimmune responses. Dermatan sulfate (DS), a glycosaminoglycan crucial for wound healing, has unique affinity for autoantigens (autoAgs) from apoptotic cells. DS-autoAg complexes are capable of stimulating autoreactive B cells and autoantibody production. Using DS affinity, we identified an autoantigenome of 408 proteins from human fetal lung fibroblast HFL11 cells, at least 231 of which are known autoAgs. Comparing with available COVID data, 352 proteins of the autoantigenome have thus far been found to be altered at protein or RNA levels in SARS-Cov-2 infection, 210 of which are known autoAgs. The COVID-altered proteins are significantly associated with RNA metabolism, translation, vesicles and vesicle transport, cell death, supramolecular fibrils, cytoskeleton, extracellular matrix, and interleukin signaling. They offer clues to neurological problems, fibrosis, smooth muscle dysfunction, and thrombosis. In particular, 150 altered proteins are related to the nervous system, including axon, myelin sheath, neuron projection, neuronal cell body, and olfactory bulb. An association with the melanosome is also identified. The findings from our study illustrate a strong connection between viral infection and autoimmunity. The vast number of COVID-altered proteins with propensity to become autoAgs offers an explanation for the diverse autoimmune complications in COVID patients. The variety of autoAgs related to mRNA metabolism, translation, and vesicles raises concerns about potential adverse effects of mRNA vaccines. The COVID autoantigen atlas we are establishing provides a detailed molecular map for further investigation of autoimmune sequelae of the pandemic.
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Affiliation(s)
| | - Wei Zhang
- Department of Gastroenterology, Affiliated Hospital of Guizhou Medical University, Guizhou, China
| | | | | | - Michael H. Roehrl
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, USA
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, USA
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7
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Ghannam K, Martinez Gamboa L, Kedor C, Spengler L, Kuckelkorn U, Häupl T, Burmester G, Feist E. Response to abatacept is associated with the inhibition of proteasome β1i expression in T cells of patients with rheumatoid arthritis. RMD Open 2020; 6:rmdopen-2020-001248. [PMID: 32998980 PMCID: PMC7547540 DOI: 10.1136/rmdopen-2020-001248] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 05/27/2020] [Accepted: 08/21/2020] [Indexed: 11/25/2022] Open
Abstract
Objective Abatacept is a biological disease-modifying antirheumatic drug (DMARD) used for the treatment of rheumatoid arthritis (RA) and modulates the costimulatory signal by cluster of differentiation (CD)28:CD80/CD86 interaction required for T cell activation. Since CD28-mediated signalling regulates many T cell functions including cytokine production of, for example, interferons (IFNs), it is of interest to clarify, whether response to abatacept has an effect on the IFN inducible immunoproteasome, as a central regulator of the immune response. Methods Effects of abatacept on the proteasome were investigated in 39 patients with RA over a period of 24 weeks. Using real-time PCR, transcript levels of constitutive and corresponding immunoproteasome catalytic subunits were investigated at baseline (T0), week 16 (T16) and week 24 (T24) in sorted blood cells. Proteasomal activity and induction of apoptosis after proteasome inhibition were also evaluated. Results Abatacept achieved remission or low disease activity in 55% of patients at T16 and in 70% of patients at T24. By two-way analysis of variance (ANOVA), a significant reduction of proteasome immunosubunit β1i was shown only in CD4+ and CD8+ T cells of sustained responders at both T16 and T24. One-way ANOVA analysis for each response group confirmed the results and showed a significant reduction at T24 in CD4+ and CD8+ T cells of the same group. Abatacept did not influence chymotrypsin-like activity of proteasome and had no effect on induction of apoptosis under exposure to a proteasome inhibitor in vitro. Conclusion The reduction of proteasome immunosubunit β1i in T cells of patients with RA with sustained response to abatacept suggests association of the immunoproteasome of T cells with RA disease activity.
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Affiliation(s)
- Khetam Ghannam
- Department of Rheumatology and Clinical Immunology, Charite University Hospital Berlin, Berlin, Germany
| | - Lorena Martinez Gamboa
- Department of Rheumatology and Clinical Immunology, Charite University Hospital Berlin, Berlin, Germany
| | - Claudia Kedor
- Department of Rheumatology and Clinical Immunology, Charite University Hospital Berlin, Berlin, Germany
| | - Lydia Spengler
- Department of Rheumatology and Clinical Immunology, Charite University Hospital Berlin, Berlin, Germany
| | - Ulrike Kuckelkorn
- Institute of Biochemistry, Charite University Hospital Berlin, Berlin, Germany
| | - Thomas Häupl
- Department of Rheumatology and Clinical Immunology, Charite University Hospital Berlin, Berlin, Germany
| | - Gerd Burmester
- Department of Rheumatology and Clinical Immunology, Charite University Hospital Berlin, Berlin, Germany
| | - Eugen Feist
- Helios Fachklinik Vogelsang-Gommern GmbH, Vogelsang-Gommern, Germany.,Department of Rheumatology and Clinical Immunology, Charite University Hospital Berlin, Berlin, Germany
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8
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Zhang W, Rho JH, Roehrl MH, Wang JY. A comprehensive autoantigen-ome of autoimmune liver diseases identified from dermatan sulfate affinity enrichment of liver tissue proteins. BMC Immunol 2019; 20:21. [PMID: 31242852 PMCID: PMC6595630 DOI: 10.1186/s12865-019-0304-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 06/19/2019] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Autoimmune diseases result from aberrant immune attacks by the body itself. It is mysterious how autoantigens, a large cohort of seemingly unconnected molecules expressed in different parts of the body, can induce similar autoimmune responses. We have previously found that dermatan sulfate (DS) can form complexes with molecules of apoptotic cells and stimulate autoreactive CD5+ B cells to produce autoantibodies. Hence, autoantigenic molecules share a unique biochemical property in their affinity to DS. This study sought to further test this uniform principle of autoantigenicity. RESULTS Proteomes were extracted from freshly collected mouse livers. They were loaded onto columns packed with DS-Sepharose resins. Proteins were eluted with step gradients of increasing salt strength. Proteins that bound to DS with weak, moderate, or strong affinity were eluted with 0.4, 0.6, and 1.0 M NaCl, respectively. After desalting, trypsin digestion, and gel electrophoresis, proteins were sequenced by mass spectrometry. To validate whether these proteins have been previously identified as autoantigens, an extensive literature search was conducted using the protein name or its alternative names as keywords. Of the 41 proteins identified from the strong DS-affinity fraction, 33 (80%) were verified autoantigens. Of the 46 proteins with moderate DS-affinity, 27 (59%) were verified autoantigens. Of the 125 proteins with weak DS-affinity, 44 (35%) were known autoantigens. Strikingly, these autoantigens fell into the classical autoantibody categories of autoimmune liver diseases: ANA (anti-nuclear autoantibodies), SMA (anti-smooth muscle autoantibodies), AMA (anti-mitochondrial autoantibodies), and LKM (liver-kidney microsomal autoantigens). CONCLUSIONS This study of DS-affinity enrichment of liver proteins establishes a comprehensive autoantigen-ome for autoimmune liver diseases, yielding 104 verified and 108 potential autoantigens. The liver autoantigen-ome sheds light on the molecular origins of autoimmune liver diseases and further supports the notion of a unifying biochemical principle of autoantigenicity.
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Affiliation(s)
- Wei Zhang
- Department of Gastroenterology, Affiliated Hospital of Guizhou Medical University, Guiyang, Guizhou, China
| | | | - Michael H Roehrl
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, USA.
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9
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Farini A, Sitzia C, Cassani B, Cassinelli L, Rigoni R, Colleoni F, Fusco N, Gatti S, Bella P, Villa C, Napolitano F, Maiavacca R, Bosari S, Villa A, Torrente Y. Therapeutic Potential of Immunoproteasome Inhibition in Duchenne Muscular Dystrophy. Mol Ther 2016; 24:1898-1912. [PMID: 27506451 DOI: 10.1038/mt.2016.162] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 07/28/2016] [Indexed: 01/24/2023] Open
Abstract
Duchenne muscular dystrophy is an inherited fatal genetic disease characterized by mutations in dystrophin gene, causing membrane fragility leading to myofiber necrosis and inflammatory cell recruitment in dystrophic muscles. The resulting environment enriched in proinflammatory cytokines, like IFN-γ and TNF-α, determines the transformation of myofiber constitutive proteasome into the immunoproteasome, a multisubunit complex involved in the activation of cell-mediate immunity. This event has a fundamental role in producing peptides for antigen presentation by MHC class I, for the immune response and also for cytokine production and T-cell differentiation. Here, we characterized for the first time the presence of T-lymphocytes activated against revertant dystrophin epitopes, in the animal model of Duchenne muscular dystrophy, the mdx mice. Moreover, we specifically blocked i-proteasome subunit LMP7, which was up-regulated in dystrophic skeletal muscles, and we demonstrated the rescue of the dystrophin expression and the amelioration of the dystrophic phenotype. The i-proteasome blocking lowered myofiber MHC class I expression and self-antigen presentation to T cells, thus reducing the specific antidystrophin T cell response, the muscular cell infiltrate, and proinflammatory cytokine production, together with muscle force recovery. We suggest that i-proteasome inhibition should be considered as new promising therapeutic approach for Duchenne muscular dystrophy pathology.
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Affiliation(s)
- Andrea Farini
- Stem Cell Laboratory, Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Unit of Neurology, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Centro Dino Ferrari, Milan, Italy
| | - Clementina Sitzia
- Stem Cell Laboratory, Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Unit of Neurology, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Centro Dino Ferrari, Milan, Italy; Department of Laboratory Medicine, University Milano Bicocca, Desio Hospital, Desio (MB), Italy
| | - Barbara Cassani
- Milan Unit, Istituto di Ricerca Genetica e Biomedica, Consiglio Nazionale delle Ricerche, Milan, Italy; Humanitas Clinical and Research Center, Milan, Italy
| | - Letizia Cassinelli
- Stem Cell Laboratory, Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Unit of Neurology, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Centro Dino Ferrari, Milan, Italy
| | - Rosita Rigoni
- Milan Unit, Istituto di Ricerca Genetica e Biomedica, Consiglio Nazionale delle Ricerche, Milan, Italy; Humanitas Clinical and Research Center, Milan, Italy
| | - Federica Colleoni
- Stem Cell Laboratory, Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Unit of Neurology, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Centro Dino Ferrari, Milan, Italy
| | - Nicola Fusco
- Department of Pathophysiology and Organ Transplantation, University of Milan, Milan, Italy; Division of Pathology, Fondazione IRCCS Cà Granda - Ospedale Maggiore Policlinico, Milan, Italy
| | - Stefano Gatti
- Center for Surgical Research, Fondazione IRCCS Cà Granda, Ospedale Maggiore Policlinico, Milan, Italy
| | - Pamela Bella
- Stem Cell Laboratory, Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Unit of Neurology, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Centro Dino Ferrari, Milan, Italy
| | - Chiara Villa
- Stem Cell Laboratory, Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Unit of Neurology, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Centro Dino Ferrari, Milan, Italy
| | - Filomena Napolitano
- Laboratorio di Chimica Clinica e Microbiologia, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Milano, Italy
| | - Rita Maiavacca
- Laboratorio di Chimica Clinica e Microbiologia, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Milano, Italy
| | - Silvano Bosari
- Department of Pathophysiology and Organ Transplantation, University of Milan, Milan, Italy; Division of Pathology, Fondazione IRCCS Cà Granda - Ospedale Maggiore Policlinico, Milan, Italy
| | - Anna Villa
- Milan Unit, Istituto di Ricerca Genetica e Biomedica, Consiglio Nazionale delle Ricerche, Milan, Italy; Humanitas Clinical and Research Center, Milan, Italy
| | - Yvan Torrente
- Stem Cell Laboratory, Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Unit of Neurology, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Centro Dino Ferrari, Milan, Italy.
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10
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Differentially expressed lncRNAs and mRNAs identified by microarray analysis in GBS patients vs healthy controls. Sci Rep 2016; 6:21819. [PMID: 26898505 PMCID: PMC4761882 DOI: 10.1038/srep21819] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Accepted: 02/01/2016] [Indexed: 11/08/2022] Open
Abstract
The aim of our present study was to determine whether message RNAs (mRNAs) and long noncoding RNAs (lncRNAs) are expressed differentially in patients with Guillain-Barré syndrome (GBS) compared with healthy controls. The mRNA and lncRNA profiles of GBS patients and healthy controls were generated by using microarray analysis. From microarray analysis, we listed 310 mRNAs and 114 lncRNAs with the mRMR software classed into two sample groups, GBS patients and healthy controls. KEGG mapping demonstrated that the top seven signal pathways may play important roles in GBS development. Several GO terms, such as cytosol, cellular macromolecular complex assembly, cell cycle, ligase activity, protein catabolic process, etc., were enriched in gene lists, suggesting a potential correlation with GBS development. Co-expression network analysis indicated that 113 lncRNAs and 303 mRNAs were included in the co-expression network. Our present study showed that these differentially expressed mRNAs and lncRNAs may play important roles in GBS development, which provides basic information for defining the mechanism(s) that promote GBS.
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11
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Bonella F, Sixt S, Thomassen J, Schmidt M, Cai M, Mori T, Guzman J, Costabel U. Extracellular 20S proteasome in BAL and serum of patients with alveolar proteinosis. Immunobiology 2015; 220:382-8. [DOI: 10.1016/j.imbio.2014.10.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Revised: 09/17/2014] [Accepted: 10/12/2014] [Indexed: 10/24/2022]
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12
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Verbrugge SE, Scheper RJ, Lems WF, de Gruijl TD, Jansen G. Proteasome inhibitors as experimental therapeutics of autoimmune diseases. Arthritis Res Ther 2015; 17:17. [PMID: 25889583 PMCID: PMC4308859 DOI: 10.1186/s13075-015-0529-1] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Current treatment strategies for rheumatoid arthritis (RA) consisting of disease-modifying anti-rheumatic drugs or biological agents are not always effective, hence driving the demand for new experimental therapeutics. The antiproliferative capacity of proteasome inhibitors (PIs) has received considerable attention given the success of their first prototypical representative, bortezomib (BTZ), in the treatment of B cell and plasma cell-related hematological malignancies. Therapeutic application of PIs in an autoimmune disease setting is much less explored, despite a clear rationale of (immuno) proteasome involvement in (auto)antigen presentation, and PIs harboring the capacity to inhibit the activation of nuclear factor-κB and suppress the release of pro-inflammatory cytokines such as tumor necrosis factor alpha and interleukin-6. Here, we review the clinical positioning of (immuno) proteasomes in autoimmune diseases, in particular RA, systemic lupus erythematosus, Sjögren's syndrome and sclerodema, and elaborate on (pre)clinical data related to the impact of BTZ and next generation PIs on immune effector cells (T cells, B cells, dendritic cells, macrophages, osteoclasts) implicated in their pathophysiology. Finally, factors influencing long-term efficacy of PIs, their current (pre)clinical status and future perspectives as anti-inflammatory and anti-arthritic agents are discussed.
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Affiliation(s)
- Sue Ellen Verbrugge
- Department of Rheumatology, VU University Medical Center, 1081 HV, Amsterdam, The Netherlands.
| | - Rik J Scheper
- Department of Pathology, VU University Medical Center, 1081 HV, Amsterdam, The Netherlands.
| | - Willem F Lems
- Department of Rheumatology, VU University Medical Center, 1081 HV, Amsterdam, The Netherlands.
| | - Tanja D de Gruijl
- Department of Medical Oncology, VU University Medical Center, 1081 HV, Amsterdam, The Netherlands.
| | - Gerrit Jansen
- Department of Rheumatology, VU University Medical Center, 1081 HV, Amsterdam, The Netherlands.
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13
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Sjakste T, Paramonova N, Rumba-Rozenfelde I, Trapina I, Sugoka O, Sjakste N. Juvenile idiopathic arthritis subtype- and sex-specific associations with genetic variants in the PSMA6/PSMC6/PSMA3 gene cluster. Pediatr Neonatol 2014; 55:393-403. [PMID: 24875235 DOI: 10.1016/j.pedneo.2014.01.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Revised: 12/25/2013] [Accepted: 01/30/2014] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND The ubiquitin proteasome system plays an exceptional biological role in the antigen processing and immune response and it could potentially be involved in pathogenesis of many immunity-related diseases, including juvenile idiopathic arthritis (JIA). METHODS The PSMB5 (rs11543947), PSMA6 (rs2277460, rs1048990), PSMC6 (rs2295826, rs2295827), and PSMA3 (rs2348071) proteasomal genes were genotyped on JIA subtype- and sex-specific association; plasma proteasome levels was measured in patients having risk and protective four-locus genotypes and eventual functional significance of allele substitutions was evaluated in silico. RESULTS Loci rs11543947 and rs1048990 were identified as disease neutral and other loci as disease susceptible (p < 0.05). The rs2277460, rs2295826, and rs2295827 loci had the strongest association with oligoarthritis [odds ratio (OR) = 2.024, 95% confidence interval (CI) 1.101-3.722; OR = 2.371, 95% CI 1.390-4.044; OR = 2.183, 95% CI 1.272-2.737, respectively), but the rs2348071 locus was associated with polyarthritis in females (OR = 3.438, 95% CI 1.626-7.265). A strong (p < 0.001) association was detected between the rs2277460/rs2295826/rs2295827/rs2348071 four-locus genotypes and the healthy phenotype when all loci were homozygous on common alleles (OR 0.439, 95% CI 0.283-0.681) and with the disease phenotype when the rs2348071 and the rs2295826 and/or rs2295827 loci were represented by risk genotypes simultaneously (OR 4.674, 95% CI 2.096-10.425). Rarely observed in controls, the double rs2277460/rs2348071 heterozygotes were rather frequent in affected males and more strongly associated with polyarthritis (p < 0.05). Haplotypes carrying the rare rs2295826/rs2295827 and rs2277460 alleles showed a strong (p < 0.001) association with oligo- and polyarthritis, respectively. The plasma proteasome level was found to be significantly higher in females having four-locus risk genotypes compared with protective genotypes (p < 0.001). Sequence affinity to transcription factors and similarity to splicing signals, microRNAs and/or hairpin precursors potentially depend on allele substitutions in disease susceptible loci. CONCLUSION We demonstrate for the first time evidence of a sex-specific association of PSMA6/PSMC6/PSMA3 genetic variants with subtypes of JIA and plasma proteasome concentrations. Theoretical models of the functional significance of allele substitutions are discussed.
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Affiliation(s)
- Tatjana Sjakste
- Institute of Biology, University of Latvia, Salaspils, Latvia.
| | | | | | - Ilva Trapina
- Latvian Institute of Organic Synthesis, Riga, Latvia
| | - Olga Sugoka
- Institute of Biology, University of Latvia, Salaspils, Latvia
| | - Nikolajs Sjakste
- Faculty of Medicine, University of Latvia, Riga, Latvia; Latvian Institute of Organic Synthesis, Riga, Latvia
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Upregulation of immunoproteasome subunits in myositis indicates active inflammation with involvement of antigen presenting cells, CD8 T-cells and IFNΓ. PLoS One 2014; 9:e104048. [PMID: 25098831 PMCID: PMC4123911 DOI: 10.1371/journal.pone.0104048] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Accepted: 07/06/2014] [Indexed: 12/24/2022] Open
Abstract
Objective In idiopathic inflammatory myopathies (IIM) infiltration of immune cells into muscle and upregulation of MHC-I expression implies increased antigen presentation and involvement of the proteasome system. To decipher the role of immunoproteasomes in myositis, we investigated individual cell types and muscle tissues and focused on possible immune triggers. Methods Expression of constitutive (PSMB5, -6, -7) and corresponding immunoproteasomal subunits (PSMB8, -9, -10) was analyzed by real-time RT-PCR in muscle biopsies and sorted peripheral blood cells of patients with IIM, non-inflammatory myopathies (NIM) and healthy donors (HD). Protein analysis in muscle biopsies was performed by western blot. Affymetrix HG-U133 platform derived transcriptome data from biopsies of different muscle diseases and from immune cell types as well as monocyte stimulation experiments were used for validation, coregulation and coexpression analyses. Results Real-time RT-PCR revealed significantly increased expression of immunoproteasomal subunits (PSMB8/-9/-10) in DC, monocytes and CD8+ T-cells in IIM. In muscle biopsies, the immunosubunits were elevated in IIM compared to NIM and exceeded levels of matched blood samples. Proteins of PSMB8 and -9 were found only in IIM but not NIM muscle biopsies. Reanalysis of 78 myositis and 20 healthy muscle transcriptomes confirmed these results and revealed involvement of the antigen processing and presentation pathway. Comparison with reference profiles of sorted immune cells and healthy muscle confirmed upregulation of PSMB8 and -9 in myositis biopsies beyond infiltration related changes. This upregulation correlated highest with STAT1, IRF1 and IFNγ expression. Elevation of T-cell specific transcripts in active IIM muscles was accompanied by increased expression of DC and monocyte marker genes and thus reflects the cell type specific involvement observed in peripheral blood. Conclusions Immunoproteasomes seem to indicate IIM activity and suggest that dominant involvement of antigen processing and presentation may qualify these diseases exemplarily for the evolving therapeutic concepts of immunoproteasome specific inhibition.
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Matsushita M, Matsudaira R, Ikeda K, Nawata M, Tamura N, Takasaki Y. Anti-proteasome activator 28α is a novel anti-cytoplasmic antibody in patients with systemic lupus erythematosus and Sjögren’s syndrome. Mod Rheumatol 2014. [DOI: 10.3109/s10165-009-0215-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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16
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Moulton VR, Gillooly AR, Tsokos GC. Ubiquitination regulates expression of the serine/arginine-rich splicing factor 1 (SRSF1) in normal and systemic lupus erythematosus (SLE) T cells. J Biol Chem 2013; 289:4126-34. [PMID: 24368769 DOI: 10.1074/jbc.m113.518662] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
T cells from patients with systemic lupus erythematosus (SLE) exhibit reduced expression of the critical T cell receptor (TCR)-associated CD3ζ signaling chain and are poor producers of the vital cytokine IL-2. By oligonucleotide pulldown and mass spectrometry discovery approaches, we identified the splicing regulator serine/arginine-rich splicing factor (SRSF) 1 or splicing factor 2/alternative splicing factor (SF2/ASF) to be important in the expression of CD3ζ chain. Importantly, increases in the expression of SRSF1 rescued IL-2 production in T cells from patients with SLE. In this study, we investigated the regulation of SRSF1 expression in resting and activated human T cells. We found that T cell stimulation induced a rapid and significant increase in mRNA expression of SRSF1; however, protein expression levels did not correlate with this increase. Co-engagement of CD28 induced a similar mRNA induction and reduction in protein levels. Proteasomal but not lysosomal degradation was involved in this down-regulation as evidenced by blocking with specific inhibitors MG132 and bafilomycin, respectively. Immunoprecipitation studies showed increased ubiquitination of SRSF1 in activated T cells. Interestingly, T cells from patients with SLE showed increased ubiquitination of SRSF1 when compared with those from healthy individuals. Our results demonstrate a novel mechanism of regulation of the splicing factor SRSF1 in human T cells and a potential molecular mechanism that controls its expression in SLE.
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Affiliation(s)
- Vaishali R Moulton
- From the Division of Rheumatology, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215
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17
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Herrada AA, Llanos C, Mackern-Oberti JP, Carreño LJ, Henriquez C, Gómez RS, Gutierrez MA, Anegon I, Jacobelli SH, Kalergis AM. Haem oxygenase 1 expression is altered in monocytes from patients with systemic lupus erythematosus. Immunology 2012; 136:414-24. [PMID: 22587389 DOI: 10.1111/j.1365-2567.2012.03598.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by multiple functional alterations affecting immune cells, such as B cells, T cells, dendritic cells (DCs) and monocytes. During SLE, the immunogenicity of monocytes and DCs is significantly up-regulated, promoting the activation of self-reactive T cells. Accordingly, it is important to understand the contribution of these cells to the pathogenesis of SLE and the mechanisms responsible for their altered functionality during disease. One of the key enzymes that control monocyte and DC function is haem oxygenase-1 (HO-1), which catalyses the degradation of the haem group into biliverdin, carbon monoxide and free iron. These products possess immunosuppressive and anti-inflammatory capacities. The main goal of this work was to determine HO-1 expression in monocytes and DCs from patients with SLE and healthy controls. Hence, peripheral blood mononuclear cells were obtained from 43 patients with SLE and 30 healthy controls. CD14(+) monocytes and CD4(+) T cells were sorted by FACS and HO-1 expression was measured by RT-PCR. In addition, HO-1 protein expression was determined by FACS. HO-1 levels in monocytes were significantly reduced in patients with SLE compared with healthy controls. These results were confirmed by flow cytometry. No differences were observed in other cell types, such as DCs or CD4(+) T cells, although decreased MHC-II levels were observed in DCs from patients with SLE. In conclusion, we found a significant decrease in HO-1 expression, specifically in monocytes from patients with SLE, suggesting that an imbalance of monocyte function could be partly the result of a decrease in HO-1 expression.
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Affiliation(s)
- Andrés A Herrada
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
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18
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Abstract
The ubiquitin-proteasomal system is an essential element of the protein quality control machinery in cells. The central part of this system is the 20S proteasome. The proteasome is a barrel-shaped multienzyme complex, containing several active centers hidden at the inner surface of the hollow cylinder. So, the regulation of the substrate entry toward the inner proteasomal surface is a key control mechanism of the activity of this protease. This chapter outlines the knowledge on the structure of the subunits of the 20S proteasome, the binding and structure of some proteasomal regulators and inducible proteasomal subunits. Therefore, this chapter imparts the knowledge on proteasomal structure which is required for the understanding of the following chapters.
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19
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Sibilia J, Chatelus E, Meyer A, Gottenberg JE, Sordet C, Goetz J. [How can we diagnose and better understand inflammatory myopathies? The usefulness of auto-antibodies]. Presse Med 2010; 39:1010-25. [PMID: 20655695 DOI: 10.1016/j.lpm.2010.06.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2009] [Revised: 05/26/2010] [Accepted: 06/02/2010] [Indexed: 01/30/2023] Open
Abstract
The inflammatory myopathies are a group of quite proteiform, systemic auto-immune diseases which include polymyositis, dermatomyositis and inclusion body myopathies. To facilitate the diagnosis, classification criteria (Bohan and Peter, 1975) have been proposed, based essentially on clinical criteria. In addition, over the past fifteen years, auto-antibodies characterizing certain forms of inflammatory myopathy have been identified. One distinguishes schematically: auto-antibodies specific for myositis and auto-antibodies sometimes associated with myositis. Concerning the myositis specific auto-antibodies (MSA), schematically there are a dozen specificities which are classed according to the cellular distribution of the auto-antigen. The most characteristic are certainly the auto-antibodies directed against cytoplasmic antigens: the anti-tRNA synthetases (anti-Jo-1 (PL-1), anti-PL-7, PL-12, EJ, OJ, JS, KS, ZO, YRS), anti-SRP (signal recognition particle), anti-Mas and anti-KJ, anti-Fer (eEF1), anti-Wa and anti-CADM p140. Other auto-antibodies are directed against nuclear auto-antigens: the anti-Mi-2, anti-PMS (PMS1, PMS2) and related antibodies (MLH1, DNA PKcs…), anti-56 kDa, anti-MJ (NXP-2), anti-SAE and anti-p155/p140 (TIF-1γ). Concerning the auto-antibodies sometimes associated with myositis (myositis associated auto-antibodies or MAA), they can also be observed in other auto-immune diseases. These auto-antibodies are directed against nuclear or nucleolar auto-antigens: the anti-PM-Scl, anti-Ku, anti-RNP (U1 RNP and U2 RNP, U4/U6 RNP and U5 RNP), anti-Ro 52 kDa and more rarely, anti-Ro 60 kDa and anti-La. The auto-antibodies related to myositis are biological tools which are of interest in two main ways. They have allowed us to sort out the nosology of these inflammatory myopathies, in particular by defining anti-tRNA synthetase syndrome. It now remains to determine how they might be employed to complement the classical clinico-biological diagnostic criteria. In this perspective, it will be indispensable first of all to diffuse and standardize the methods of detection. The latter are at the moment very heterogeneous as they use techniques and above all antigenic preparations which are extremely diverse. These antibodies are also very interesting "physiopathological" tools to try to better understand myositis. The example of anti-tRNA synthetases is a particularly original model of auto-immunization, which allows one to establish a link between an initial, probably poorly specific muscular lesion and the appearance of auto-antibodies which maintain and aggravate the muscular disease.
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Affiliation(s)
- Jean Sibilia
- CHU de Strasbourg, hôpital Hautepierre, service de rhumatologie, laboratoire d'immunologie, 67098 Strasbourg cedex, France.
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20
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Sorokin AV, Kim ER, Ovchinnikov LP. Proteasome system of protein degradation and processing. BIOCHEMISTRY (MOSCOW) 2010; 74:1411-42. [PMID: 20210701 DOI: 10.1134/s000629790913001x] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
In eukaryotic cells, degradation of most intracellular proteins is realized by proteasomes. The substrates for proteolysis are selected by the fact that the gate to the proteolytic chamber of the proteasome is usually closed, and only proteins carrying a special "label" can get into it. A polyubiquitin chain plays the role of the "label": degradation affects proteins conjugated with a ubiquitin (Ub) chain that consists at minimum of four molecules. Upon entering the proteasome channel, the polypeptide chain of the protein unfolds and stretches along it, being hydrolyzed to short peptides. Ubiquitin per se does not get into the proteasome, but, after destruction of the "labeled" molecule, it is released and labels another molecule. This process has been named "Ub-dependent protein degradation". In this review we systematize current data on the Ub-proteasome system, describe in detail proteasome structure, the ubiquitination system, and the classical ATP/Ub-dependent mechanism of protein degradation, as well as try to focus readers' attention on the existence of alternative mechanisms of proteasomal degradation and processing of proteins. Data on damages of the proteasome system that lead to the development of different diseases are given separately.
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Affiliation(s)
- A V Sorokin
- Institute of Protein Research, Russian Academy of Sciences, Pushchino, Moscow Region, Russia.
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21
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Voigt A, Trimpert C, Bartel K, Egerer K, Kuckelkorn U, Feist E, Gericke C, Klingel K, Kandolf R, Felix SB, Baumann G, Kloetzel PM, Stangl K, Staudt A. Lack of evidence for a pathogenic role of proteasome-directed autoimmunity in dilated cardiomyopathy. Basic Res Cardiol 2010; 105:557-67. [DOI: 10.1007/s00395-010-0096-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2009] [Revised: 03/12/2010] [Accepted: 03/13/2010] [Indexed: 01/10/2023]
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22
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Voigt A, Bartel K, Egerer K, Trimpert C, Feist E, Gericke C, Kandolf R, Klingel K, Kuckelkorn U, Stangl K, Felix SB, Baumann G, Kloetzel PM, Staudt A. Humoral anti-proteasomal autoimmunity in dilated cardiomyopathy. Basic Res Cardiol 2009; 105:9-18. [DOI: 10.1007/s00395-009-0061-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2009] [Revised: 08/31/2009] [Accepted: 09/02/2009] [Indexed: 11/28/2022]
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23
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Matsushita M, Matsudaira R, Ikeda K, Nawata M, Tamura N, Takasaki Y. Anti-proteasome activator 28alpha is a novel anti-cytoplasmic antibody in patients with systemic lupus erythematosus and Sjögren's syndrome. Mod Rheumatol 2009; 19:622-8. [PMID: 19688289 DOI: 10.1007/s10165-009-0215-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2009] [Accepted: 07/14/2009] [Indexed: 11/26/2022]
Abstract
We evaluated the extent to which anti-proteasome activator (PA) 28alpha antibodies act as anti-cytoplasmic antibodies in systemic lupus erythematosus (SLE) and Sjögren's syndrome (SS). Sera from 46 SLE patients without SS, 11 SLE patients with SS, and 45 primary SS patients were tested. Using anti-PA28alpha and anti-PA28gamma (Ki) antibodies purified from nitrocellulose membranes onto which recombinant PA28alpha and Ki had been transferred, the cellular distributions of the targeted antigens were analyzed immunohistochemically. In addition, the incidence of anti-PA28alpha antibodies was compared with those of other anti-cytoplasmic antibodies. Immunofluorescent staining showed that purified anti-PA28alpha antibodies reacted with the cytoplasm of HEp-2 cells, whereas purified anti-Ki antibodies reacted with nucleoplasm. Among the 15 SLE patients without SS, the six SLE patients with SS, and the 30 primary SS patients who were anti-cytoplasmic-antibody positive, anti-SS-A/Ro antibodies were the most frequently detected (53, 67, and 70%, respectively); anti-PA28alpha antibodies were, respectively, detected in 33, 50, and 40% of those patient groups, incidences that were higher than those of anti-ribosomal P, anti-smooth muscle and anti-mitochondrial M2 antibodies. These results show that anti-PA28alpha antibodies are major anti-cytoplasmic antibodies in patients with SLE and SS, and the distinct cellular distributions of PA28alpha and Ki suggest these proteins are associated with different cellular functions.
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Affiliation(s)
- Masakazu Matsushita
- Department of Internal Medicine and Rheumatology, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan.
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Circulating 20S proteasome levels in patients with mixed connective tissue disease and systemic lupus erythematosus. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2008; 15:1489-93. [PMID: 18667633 DOI: 10.1128/cvi.00187-08] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The associations of circulating 20S proteasomes (c20S) with clinical and serologic disease indices in patients with systemic lupus erythematosus (SLE) and mixed connective tissue disease (MCTD) are unknown. We present the initial report that c20S levels are elevated in MCTD and correlate with clinically relevant changes in disease activity in SLE and MCTD.
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Thuy-Tien H, Haugen M, Aarseth J, Storstein A, Vedeler CA. Proteasome antibodies in patients with cancer or multiple sclerosis. Scand J Immunol 2008; 67:400-3. [PMID: 18266796 DOI: 10.1111/j.1365-3083.2008.02073.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Proteasome antibodies were detected by enzyme-linked immunosorbent assay in two of the 45 (4.4%) patients with lung cancer, 0 of the 39 patients with breast cancer and six of the 51 (11.8%) patients with ovarian cancer. Six of the 47 (12.8%) patients with relapsing remitting multiple sclerosis had proteasome antibodies, as well as two of the 100 (2%) blood donors. Significant higher odds ratios compared to the blood donors were found for the patients with ovarian cancer (OR: 6.4; 95% CI: 1.1-68) and multiple sclerosis (OR: 7.1; 95% CI: 1.2-74). There was no association between proteasome antibodies and metastases or onconeural antibodies. The antibodies showed reactivity to 23, 25 and 27 kD proteins of the 20S proteasome using Western blot. The increased prevalence of proteasome antibodies in patients with ovarian cancer or multiple sclerosis may reflect cellular damage and release of intracellular antigens. Whether the antibodies take part in the clearance of released proteasomes and thus participate in the pathogenesis of cancer or autoimmune disease is not known.
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Affiliation(s)
- H Thuy-Tien
- Department of Neurology, Haukeland University Hospital, University of Bergen, Bergen, Norway
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Konstantinova IM, Tsimokha AS, Mittenberg AG. Role of proteasomes in cellular regulation. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2008; 267:59-124. [PMID: 18544497 DOI: 10.1016/s1937-6448(08)00602-3] [Citation(s) in RCA: 124] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The 26S proteasome is the key enzyme of the ubiquitin-dependent pathway of protein degradation. This energy-dependent nanomachine is composed of a 20S catalytic core and associated regulatory complexes. The eukaryotic 20S proteasomes demonstrate besides several kinds of peptidase activities, the endoribonuclease, protein-chaperone and DNA-helicase activities. Ubiquitin-proteasome pathway controls the levels of the key regulatory proteins in the cell and thus is essential for life and is involved in regulation of crucial cellular processes. Proteasome population in the cell is structurally and functionally heterogeneous. These complexes are subjected to tightly organized regulation, particularly, to a variety of posttranslational modifications. In this review we will summarize the current state of knowledge regarding proteasome participation in the control of cell cycle, apoptosis, differentiation, modulation of immune responses, reprogramming of these particles during these processes, their heterogeneity and involvement in the main levels of gene expression.
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Sixt SU, Beiderlinden M, Jennissen HP, Peters J. Extracellular proteasome in the human alveolar space: a new housekeeping enzyme? Am J Physiol Lung Cell Mol Physiol 2007; 292:L1280-8. [PMID: 17220374 DOI: 10.1152/ajplung.00140.2006] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
We hypothesized that 20S proteasome is present and functional in the extracellular alveolar space in humans. Proteasomal activity was measured in bronchoalveolar lavage (BAL) supernatant from eight humans using specific proteasomal fluorogenic substrates and I(125)-albumin with and without specific proteasome inhibitors. Furthermore, gelfiltration, Western blot technique, and mass spectrometry were applied for proteasome characterization. All proteasomal fluorogenic substrates were hydrolyzed by BAL supernatant, with hydrolysis inhibited by epoxomicin (P = 0.024) and other proteasome inhibitors as well. E64, a lysosomal inhibitor, did not inhibit enzyme activity. The majority of proteolytic activity was detected in BAL supernatant rather than in the cell pellet. No correlation was found between proteasomal hydrolysis in BAL supernatant and lactate dehydrogenase activity, the total cell count in the cell pellet, and the fraction of avital cells in the cell pellet, ruling out cell lysis as a major source of proteasomal activity. Gelfiltration revealed hydrolyzing activity in the supernatant at 660 kDa and proteasome core proteins after analysis by ESI-QqTOF mass spectrometry. Furthermore, Western blots using a polyclonal antibody against proteasomal alpha-/beta-subunits detected proteasomal proteins in the typical 20- to 30-kDa range in BAL supernatant. Incubation of BAL supernatant with I(125)-albumin showed a high mean cleavage rate (101.8 microg/ml x h lavage +/- 46 SD) that was inhibited by epoxomicin (P = 0.013) and was ATP and ubiquitin independent. We identified for the first time extracellular, biologically active, ATP- and ubiquitin-independent 20S proteasome in the human alveolar space, with a high albumin cleavage rate. Possibly, the proteasome assists in maintenance of a low intra-alveolar oncotic pressure and/or alveolar protein degradation.
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Affiliation(s)
- Stephan Urs Sixt
- Klinik für Anästhesiologie und Intensivmedizin, Universitätsklinikum Essen, Essen, Germany
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Sordet C, Goetz J, Sibilia J. Contribution of autoantibodies to the diagnosis and nosology of inflammatory muscle disease. Joint Bone Spine 2006; 73:646-54. [PMID: 17110150 DOI: 10.1016/j.jbspin.2006.04.005] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2006] [Accepted: 04/07/2006] [Indexed: 01/26/2023]
Abstract
The myositides are systemic autoimmune conditions of which the most important are polymyositis, dermatomyositis, and inclusion body myositis. In addition to the classic clinical diagnostic criteria, myositis-specific autoantibodies were identified about 15 years ago. Among the dozen or so myositis-specific autoantibodies reported to date, the most characteristic are directed against cytoplasmic antigens, such as tRNA synthetase (Jo-1 or PL-1, PL-7, PL-12, EJ, OJ, JS, and KS), signal-recognition particle (SRP), Mas, KJ, Fer (eEF1), and Wa. Antibodies to nuclear antigens include anti-Mi-2, anti-PMS (PMS1, and PMS2), and related antibodies (MLH1, DNA protein kinase catalytic subunit (DNA PKCS)...), and anti-56 kDa. Myositis-associated antibodies are not specific but may be found in patients with myositis. They are directed to nuclear or nucleolar antigens such as PM-Scl, Ku, RNP (U1-RNP and U2-RNP, U4/U6-RNP, and U5-RNP), Ro 52 kDa and, more rarely, Ro 60 kDa and La. Myositis-specific antibodies have proved useful on two fronts. They have improved the diagnosis of myositis by leading to the identification of characteristic clinical patterns, such as anti-synthetase syndrome. The place of autoantibodies alongside classic clinical and laboratory criteria remains to be determined, however. First, standardized assays will have to be developed to replace current detection methods, which use widely variable techniques and antigen preparations. Myositis-specific antibodies have also shed light on the pathogenesis of myositis. For instance, the development of antibodies to tRNA synthetases constitutes an original autoimmunity model that shows how muscle damage, probably of a nonspecific nature, can lead to the production of autoantibodies that perpetuate and aggravate the muscle lesions.
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Affiliation(s)
- Christelle Sordet
- Rheumatology Department and Immunology Laboratory, Strasbourg Teaching Hospital, Louis Pasteur University, EA 3432 Strasbourg, France
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Brychcy M, Kuckelkorn U, Hausdorf G, Egerer K, Kloetzel PM, Burmester GR, Feist E. Anti-20S proteasome autoantibodies inhibit proteasome stimulation by proteasome activator PA28. ACTA ACUST UNITED AC 2006; 54:2175-83. [PMID: 16802355 DOI: 10.1002/art.21970] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE The ubiquitin-proteasome system plays a central role in cellular homeostasis as well as in regulation of the inflammatory and stress responses. However, the occurrence of autoantibodies against 20S proteasome has, to date, been considered to be a non-specific epiphenomenon in patients with autoimmune disorders. This study was undertaken to analyze the properties of antiproteasome antibodies by investigating their influence on the proteolytic activity of the proteasome complex. METHODS The 20S proteasome, with or without addition of the proteasome activator (PA28), was preincubated with affinity-purified human antiproteasome antibodies. Proteolytic activity was estimated using fluorogenic peptides as substrate. RESULTS The baseline proteolytic properties of the 20S proteasome core complex were not influenced by the autoantibodies in vitro. In contrast, all human antiproteasome antibodies analyzed efficiently blocked the enhanced proteasomal substrate cleavage provided by PA28. A similar influence of proteasome activation was observed upon preincubation with affinity-purified sheep polyclonal or mouse monoclonal antiproteasome antibody, whereas human immunoglobulin controls exhibited no effect. CONCLUSION Autoantibodies against 20S proteasomes are able to block proteasome activation by PA28, binding to their native antigen in vitro. Antibody targeting of the interaction between 20S proteasome and PA28 represents a novel mechanism of proteasome inhibition.
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Affiliation(s)
- Michael Brychcy
- Department of Rheumatology and Clinical Immunology, Charité-Universitätsmedizin Berlin, Schumannstrasse 20/21, D-10117 Berlin, Germany
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30
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Feist E, Brychcy M, Hausdorf G, Hoyer B, Egerer K, Dörner T, Kuckelkorn U, Burmester GR. Anti-proteasome autoantibodies contribute to anti-nuclear antibody patterns on human larynx carcinoma cells. Ann Rheum Dis 2006; 66:5-11. [PMID: 16815863 PMCID: PMC1798404 DOI: 10.1136/ard.2006.055152] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND Autoantibodies to the 20S proteasome represent an unspecific but common serological phenomenon in patients with systemic autoimmune diseases. Interestingly, a high prevalence of these antibodies have been observed in patients with connective tissue diseases, where anti-nuclear antibodies (ANAs) serve as an important diagnostic screening test. OBJECTIVE To disclose interference of anti-proteasome antibodies with known ANA patterns. METHODS Anti-proteasome antibodies were isolated for comprehensive immunofluorescence analyses. The immunofluorescence pattern of human anti-proteasome antibodies was compared with a panel of monoclonal and polyclonal reference antibodies, and colocalisation was analysed using confocal microscopy. RESULTS Anti-proteasome antibodies clearly contributed to the ANA patterns of their respective serum samples from patients with different rheumatic disorders. In addition to the nuclear pattern, proteasomal staining was also detectable in the cytoplasm, at the endoplasmic reticulum and perinuclear regions showing features overlapping with other known autoantibodies such as those to mitochondria. The specificity of anti-proteasome antibodies was proved by competition experiments and by colocalisation with monoclonal reference antibodies in confocal microscopy. CONCLUSION In ANA diagnostics, interference of anti-proteasome antibodies will have to be taken into account, especially in the differentiation of anti-cytoplasmatic autoantibodies.
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Affiliation(s)
- E Feist
- Department of Rheumatology and Clinical Immunology, Charité-Universitätsmedizin Berlin, Charitéplatz 1, Berlin D-10117, Germany.
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31
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Krause S, Kuckelkorn U, Dörner T, Burmester GR, Feist E, Kloetzel PM. Immunoproteasome subunit LMP2 expression is deregulated in Sjogren's syndrome but not in other autoimmune disorders. Ann Rheum Dis 2006; 65:1021-7. [PMID: 16414974 PMCID: PMC1798250 DOI: 10.1136/ard.2005.045930] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND The proteasome system has a pivotal role in the control of the immune response, which suggests that it might be involved in the pathogenesis of autoimmune disorders. OBJECTIVE To investigate the expression profile of selected proteasomal genes in human peripheral blood mononuclear cells in patients with a variety of autoimmune diseases compared with healthy subjects. METHODS Real time quantitative RT-PCR was used to analyse the mRNA expression pattern of the proteasome activator subunits PA28alpha and PA28beta and of constitutive proteasome and interferon-gamma-inducible immunoproteasome subunits in peripheral blood mononuclear cells. Simultaneously, protein expression of selected proteasome subunits was quantified by immunoblotting. RESULTS Under systemic inflammatory conditions the proteasome subunits LMP2 (beta1i), LMP7 (beta5i), MECL1 (beta2i), and PA28alpha were expressed abundantly at the protein level in the vast majority of systemic autoimmune disorders. However, simultaneous mRNA and protein quantification showed a characteristic proteasome expression signature in primary Sjögren's syndrome. At the transcript level, the interferon-gamma-responsive subunits LMP2 (beta1i), MECL1 (beta2i), and the proteasome activator subunit PA28alpha were markedly up regulated. In contrast, LMP2 (beta1i) deficiency was evident at the protein level, indicating deregulation of proteasome expression in Sjögren's syndrome. CONCLUSIONS These data provide evidence for a regulatory defect in the proteasome system in human autoimmune disorders, pointing to a unique role for LMP2 (beta1i) in the pathogenesis of primary Sjögren's syndrome.
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Affiliation(s)
- S Krause
- Laboratory of Molecular Myology, Department of Neurology, Friedrich-Baur-Institute, Ludwig-Maximilians University, Marchioninistrasse 17, 81377 Munich, Germany.
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Storstein A, Knudsen A, Vedeler CA. Proteasome antibodies in paraneoplastic cerebellar degeneration. J Neuroimmunol 2005; 165:172-8. [PMID: 15964637 DOI: 10.1016/j.jneuroim.2005.04.024] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2005] [Accepted: 04/05/2005] [Indexed: 11/29/2022]
Abstract
Antibodies to proteasome have been detected in several autoimmune diseases, including multiple sclerosis. We have investigated the presence of such antibodies in patients with paraneoplastic neurological syndromes, by Western blotting and immunohistochemistry. Antibodies to 20S proteasome were detected in the majority of patients with paraneoplastic cerebellar degeneration (PCD), but in only one of nine sera from patients with paraneoplastic encephalomyelitis/sensory neuronopathy (PEM/SN), and were not found in cancer patients in general. The results suggest that the immune responses in PCD differ from those of PEM/SN, whereas the functional significance of proteasome antibodies in PCD is yet to be determined.
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Affiliation(s)
- Anette Storstein
- Department of Neurology, Haukeland University Hospital, N-5021 Bergen, Norway.
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33
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Gutjahr C, Murphy D, Lueking A, Koenig A, Janitz M, O'Brien J, Korn B, Horn S, Lehrach H, Cahill DJ. Mouse protein arrays from a TH1 cell cDNA library for antibody screening and serum profiling. Genomics 2005; 85:285-96. [PMID: 15718096 DOI: 10.1016/j.ygeno.2004.11.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2004] [Accepted: 11/10/2004] [Indexed: 11/22/2022]
Abstract
The mouse is the premier genetic model organism for the study of disease and development. We describe the establishment of a mouse T helper cell type 1 (T(H)1) protein expression library that provides direct access to thousands of recombinant mouse proteins, in particular those associated with immune responses. The advantage of a system based on the combination of large cDNA expression libraries with microarray technology is the direct connection of the DNA sequence information from a particular clone to its recombinant, expressed protein. We have generated a mouse T(H)1 expression cDNA library and used protein arrays of this library to characterize the specificity and cross-reactivity of antibodies. Additionally, we have profiled the autoantibody repertoire in serum of a mouse model for systemic lupus erythematosus on these protein arrays and validated the putative autoantigens on highly sensitive protein microarrays.
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Affiliation(s)
- Claudia Gutjahr
- Max Planck Institute of Molecular Genetics, Ihnestrasse 73, D-14195 Berlin, Germany
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Dunster K, Lai FPL, Sentry JW. Limkain b1, a novel human autoantigen localized to a subset of ABCD3 and PXF marked peroxisomes. Clin Exp Immunol 2005; 140:556-63. [PMID: 15932519 PMCID: PMC1809386 DOI: 10.1111/j.1365-2249.2005.02774.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Detection of self-reactive antibodies has an established role in the diagnosis and monitoring of many human autoimmune diseases. Autoantibodies with restricted reactivity to cytoplasmic compartments and structures are an occasional incidental finding following routine examination of serum for antinuclear antibody reactivity. A prerequisite for rational exploitation of self-reactive antibodies, in either clinical or research settings, is the establishment of the molecular identity of the target autoantigen(s). Here we report on the identification of a novel autoantigen that co-localizes with a subset of cytoplasmic microbodies marked by ABCD3 (PMP-70) and/or PXF (PEX19). Immunoscreening a HeLa cell cDNA expression library with a human autoimmune serum identified two clones that encode fragments of limkain b1 (LKAP). We demonstrate that mouse polyclonal antibodies raised against a bacterially expressed fragment of limkain b1 mark the same cytoplasmic structures as human serum, as does an EGFP:LKAPCT429 fusion protein expressed in HeLa cells. An immunoblot screen against a bacterially expressed MBP:LKAPCT429 fusion protein substrate, using a cohort of 16 additional human sera that display Hep 2 cell cytoplasmic staining patterns similar to the prototype serum, identified three additional sera reactive to limkain b1. This is the first report establishing the molecular identity of a peroxisomal autoantigen. Preliminary results suggest that limkain b1 may be a relatively common target of human autoantibodies reactive to cytoplasmic vesicle-like structures.
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Affiliation(s)
- K Dunster
- Alfred Pathology Service, Alfred Hospital, Melbourne, Victoria, Australia
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35
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Stoebner PE, Lavabre-Bertrand T, Henry L, Guiraud I, Carillo S, Dandurand M, Joujoux JM, Bureau JP, Meunier L. High plasma proteasome levels are detected in patients with metastatic malignant melanoma. Br J Dermatol 2005; 152:948-53. [PMID: 15888151 DOI: 10.1111/j.1365-2133.2005.06487.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Proteasomes, nonlysosomal proteolytic structures, are implicated in cell growth and differentiation. An abnormal expression has been described in haematopoietic malignancies and in some solid tumours. OBJECTIVES To study the plasma proteasome levels in patients with malignant melanoma (MM) using an enzyme-linked immunosorbent assay (ELISA) technique, and to compare them with the values obtained in a normal population and in patients with severe psoriasis or chronic idiopathic urticaria (CIU). METHODS Plasma proteasome level was measured using a sandwich ELISA test in normal donors (n = 14), and in patients with stage I/II (n = 13), stage III (n = 6) and stage IV (n = 10) MM, severe psoriasis (n = 13) and CIU (n = 6). Tissue proteasome expression was also detected by immunohistology using a monoclonal antibody in paraffin-embedded samples of normal tissue, psoriasis skin and MM. RESULTS In normal donors, mean +/- SEM plasma proteasome concentration was 2138 +/- 221 ng mL(-1). Patients with stages III and IV MM exhibited a significantly higher value (3373 +/- 470 ng mL(-1) and 8931 +/- 1232 ng mL(-1), respectively). Values in patients with stage I/II MM and CIU were not significantly different from those in normal volunteers. Patients with severe psoriasis also exhibited increased values (3398 +/- 374 ng mL(-1)) but to a lesser extent than in patients with stage IV MM. There was a significant correlation of proteasome levels with serum lactate dehydrogenase in the MM group. Tissue expression as demonstrated by immunohistochemistry paralleled these findings. The strongest expression was seen on MM slides and to a lesser extent in psoriasis samples, the weakest expression being observed in normal skin. CONCLUSIONS Proteasomes are strongly expressed in cutaneous MM; high levels of circulating proteasomes are detected in patients with metastatic MM with a high melanoma burden, and at a lesser extent in psoriatic patients, which suggests proteasomes represent a marker more of nonspecific inflammation than of early cancer.
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Affiliation(s)
- P-E Stoebner
- Service de Dermatologie, Groupe Hospitalier Universitaire Carémeau, BP 26, 30029 Nîmes, France
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36
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Wójcik C. Ubiquitin- and proteasome-dependent pathway of protein degradation as an emerging therapeutic target. ACTA ACUST UNITED AC 2005. [DOI: 10.1517/14728222.4.1.89] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Sherer Y, Gorstein A, Fritzler MJ, Shoenfeld Y. Autoantibody explosion in systemic lupus erythematosus: more than 100 different antibodies found in SLE patients. Semin Arthritis Rheum 2005; 34:501-37. [PMID: 15505768 DOI: 10.1016/j.semarthrit.2004.07.002] [Citation(s) in RCA: 421] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
OBJECTIVE Description of the various autoantibodies that can be detected in patients with systemic lupus erythematosus (SLE). METHODS A literature review, using the terms "autoantibody" and "systemic lupus erythematosus", was conducted to search for articles on autoantibodies in SLE, their target antigens, association with disease activity, or other clinical associations. RESULTS One hundred sixteen autoantibodies were described in SLE patients. These include autoantibodies that target nuclear antigens, cytoplasmic antigens, cell membrane antigens, phospholipid-associated antigens, blood cells, endothelial cells, and nervous system antigens, plasma proteins, matrix proteins, and miscellaneous antigens. The target of autoantibody, the autoantigen properties, autoantibody frequencies in SLE, as well as clinical associations, and correlation with disease activity are described for all 116 autoantibodies. CONCLUSIONS SLE is the autoimmune disease with the largest number of detectable autoantibodies. Their production could be antigen-driven, the result of polyclonal B cell activation, impaired apoptotic pathways, or the outcome of idiotypic network dysregulation.
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Affiliation(s)
- Yaniv Sherer
- Department of Medicine B and Center for Autoimmune Disease, Sheba Medical Center, Tel-Hashomer 52621, Israel
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Kamradt T, Schubert D. The role and clinical implications of G6PI in experimental models of rheumatoid arthritis. Arthritis Res Ther 2004; 7:20-8. [PMID: 15642150 PMCID: PMC1064898 DOI: 10.1186/ar1476] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The antigens that trigger the pathogenic immune response in rheumatoid arthritis (RA) remain unknown. Until recently it was assumed that either viral or microbial antigens, or joint-specific antigens were the target of arthritogenic T and B lymphocytes in RA. Consequently, murine models of arthritis are induced by immunization with either joint-specific antigens such as type II collagen or microbial products such as streptococcal cell wall. In the K/B×N T-cell receptor transgenic mouse model arthritis is caused by a systemic autoimmune response to the ubiquitously expressed glycolytic enzyme glucose-6-phosphate isomerase (G6PI). The autoreactive transgenic T cells recognize G6PI and provide help for the production of arthritogenic IgG antibodies against G6PI. More recently it was shown that G6PI immunization induces severe symmetrical peripheral polyarthritis in genetically unaltered DBA/I mice. In that model CD4+ T cells are necessary not only for the induction but also for the effector phase of arthritis. Here we review the pathomechanisms that lead from systemic autoreactivity to arthritis in these models, consider the relevance of anti-G6PI immune reactivity for RA, and discuss the insights into the pathogenesis of RA and possibly other autoimmune conditions that can be gained from these models.
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MESH Headings
- Animals
- Antibody Specificity
- Arthritis, Experimental/enzymology
- Arthritis, Experimental/etiology
- Arthritis, Experimental/immunology
- Arthritis, Rheumatoid/immunology
- Autoantibodies/immunology
- Autoantigens/immunology
- Autoimmune Diseases/enzymology
- Autoimmune Diseases/etiology
- Autoimmune Diseases/immunology
- B-Lymphocytes/immunology
- CD4-Positive T-Lymphocytes/immunology
- Cell Wall/chemistry
- Cell Wall/immunology
- Collagen Type II/immunology
- Collagen Type II/toxicity
- Complement System Proteins/immunology
- Crosses, Genetic
- Glucose-6-Phosphate Isomerase/immunology
- Histocompatibility Antigens Class II/immunology
- Humans
- Immunization
- Immunization, Passive
- Immunoglobulin G/immunology
- Interleukin-1/physiology
- Mast Cells/immunology
- Mice
- Mice, Inbred C57BL
- Mice, Inbred DBA
- Mice, Inbred NOD
- Mice, Transgenic
- Nervous System Autoimmune Disease, Experimental/etiology
- Nervous System Autoimmune Disease, Experimental/immunology
- Neutrophils/immunology
- Receptors, Antigen, T-Cell/genetics
- Receptors, Antigen, T-Cell/immunology
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Affiliation(s)
- Thomas Kamradt
- Institut für Immunologie, Klinikum der Friedrich-Schiller Universität Jena, Jena, Germany.
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Golab J, Bauer TM, Daniel V, Naujokat C. Role of the ubiquitin-proteasome pathway in the diagnosis of human diseases. Clin Chim Acta 2004; 340:27-40. [PMID: 14734194 DOI: 10.1016/j.cccn.2003.10.025] [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] [Indexed: 02/07/2023]
Abstract
The ubiquitin-proteasome pathway constitutes the major system for nuclear and extralysosomal cytosolic protein degradation in eukaryotic cells. A plethora of cell proteins implicated in the maintenance and regulation of essential cellular processes undergoes processing and functional modification by proteolytic degradation via the ubiquitin-proteasome pathway. Deregulations of the pathway have been shown to contribute to the pathogenesis of several human diseases, such as cancer, neurodegenerative, autoimmune, genetic and metabolic disorders, most of them exhibiting abnormal accumulation and altered composition of components of the pathway that is suitable for diagnostic proceedings. While the ubiquitin-proteasome pathway is currently exploited to develop novel therapeutic strategies, it is less regarded as a diagnostic area. Future research should lead to an improved understanding of the pathophysiology of the ubiquitin-proteasome pathway with the aim of allowing the development of subtle diagnostic strategies.
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Affiliation(s)
- Jakub Golab
- Department of Immunology, Center of Biostructure Research, The Medical University of Warsaw, Warsaw, Poland
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40
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Kordonouri O, Meyer K, Egerer K, Hartmann R, Scheffler S, Burmester GR, Kuckelkorn U, Danne T, Feist E. Prevalence of 20S proteasome, anti-nuclear and thyroid antibodies in young patients at onset of type 1 diabetes mellitus and the risk of autoimmune thyroiditis. J Pediatr Endocrinol Metab 2004; 17:975-81. [PMID: 15301045 DOI: 10.1515/jpem.2004.17.7.975] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Patients with type 1 diabetes mellitus (DM1) are at high risk to develop further autoimmune disorders, which are mostly characterized by the presence of organ-specific antibodies in serum and a subclinical disease course. Diabetes-related (glutamic acid decarboxylase, tyrosine phosphatase, IA-2) and thyroid-specific (thyroperoxidase, thyroglobulin) as well as antibodies to 20S proteasome, and anti-nuclear antibodies, were measured at DM1 onset in 147 children and adolescents. Patients were followed prospectively for the development of autoimmune thyroiditis (TSH elevation and/or sonographic thyroid gland enlargement in the presence of thyroid antibodies) up to 12 years, median observation time 4.4 years. Eight of 147 (5.4%) patients developed autoimmune thyroiditis. The cumulative incidence (+/-SE) at 5 years was 0.08+/-0.03. The prevalence of thyroid antibodies was 16.7%, of DM-related 88.4%, 20S proteasome 21.9%, and anti-nuclear antibodies 20.0%. There was a positive correlation between thyroid and anti-nuclear antibodies (p <0.001). Clinical course of DM1 and remission duration were not influenced by the presence of autoantibodies. However, in contrast to patients without antibodies, those with positive antibodies had significantly (p <0.001) elevated cumulative incidence of autoimmune thyroiditis at 5 years: thyroperoxidase 0.40+/-0.13, thyroglobulin 0.38+/-0.15, and anti-nuclear antibodies 0.29+/-0.12, respectively. These data underline that autoimmunity in patients with DM1 is not only restricted to beta-cell antigens at the onset of disease. In particular, patients with positive thyroid and anti-nuclear antibodies are at high risk to develop autoimmune thyroiditis during the first 5 years of DM1.
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Affiliation(s)
- Olga Kordonouri
- Clinics of General Pediatrics, Otto-Heubner-Centrum für Kinder- und Jugendmedizin Charité, Berlin, Germany.
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41
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Stinton LM, Eystathioy T, Selak S, Chan EKL, Fritzler MJ. Autoantibodies to protein transport and messenger RNA processing pathways: endosomes, lysosomes, Golgi complex, proteasomes, assemblyosomes, exosomes, and GW bodies. Clin Immunol 2004; 110:30-44. [PMID: 14962794 DOI: 10.1016/j.clim.2003.10.005] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2003] [Revised: 10/16/2003] [Accepted: 10/20/2003] [Indexed: 02/03/2023]
Abstract
Over 50 years ago the lupus erythematosus (LE) cell phenomenon was described and this was quickly followed by the introduction of the LE cell test and indirect immunofluorescence (IIF) to detect antinuclear antibodies (ANA) in clinical laboratories. Recently, attention has turned to the identification of the autoantigens that bind to cytoplasmic organelles such as the Golgi complex, endosomes and other "cytoplasmic somes". Three endosome autoantigens include early endosome antigen 1 (EEA1, 160 kDa), cytoplasmic linker protein-170 (CLIP-170, 170 kDa), and lysobisphosphatidic acid (LBPA). Antibodies to EEA1 were seen in a variety of conditions but approximately 40% of the patients had a neurological disease. Despite the prominence of lysosomes in cells and tissues, reports of autoantibodies are limited to the lysosomal antigen h-LAMP-2 and the cytoplasmic antineutrophil antibodies (cANCA). Autoantigens in the Golgi complex include giantin/macrogolgin, golgin-245, golgin 160, golgin-97, golgin 95/gm130, and golgin-67. More recently, there has been an interest in autoantibodies that bind components of the "SMN complex" or the "assemblyosome". Arginine/glycine (RG)-rich domains in components of the SMN complex interact with Sm, like-Sm (LSm), fibrillarin, RNA helicase A (Gu), and coilin proteins, all of which are antigen targets in a variety of diseases. More recently, components of a novel cytoplasmic structure named GW bodies (GWBs) have been identified as targets of human autoantibodies. Components of GWBs include GW182, a unique mRNA-binding protein, like Sm proteins (LSms), and decapping (hDcp1) and exonuclease (Xrn) enzymes. Current evidence suggests that GWBs are involved in the cytoplasmic processing of mRNAs. Autoantibodies to the "cytoplasmic somes" are relatively uncommon and serological tests to detect most of them are not widely available.
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Affiliation(s)
- Laura M Stinton
- Faculty of Medicine, University of Calgary, Calgary, AB, Canada
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42
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Mastaglia FL, Garlepp MJ, Phillips BA, Zilko PJ. Inflammatory myopathies: clinical, diagnostic and therapeutic aspects. Muscle Nerve 2003; 27:407-25. [PMID: 12661042 DOI: 10.1002/mus.10313] [Citation(s) in RCA: 147] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The three major forms of immune-mediated inflammatory myopathy are dermatomyositis (DM), polymyositis (PM), and inclusion-body myositis (IBM). They each have distinctive clinical and histopathologic features that allow the clinician to reach a specific diagnosis in most cases. Magnetic resonance imaging is sometimes helpful, particularly if the diagnosis of IBM is suspected but has not been formally evaluated. Myositis-specific antibodies are not helpful diagnostically but may be of prognostic value; most antibodies have low sensitivity. Muscle biopsy is mandatory to confirm the diagnosis of an inflammatory myopathy and to allow unusual varieties such as eosinophilic, granulomatous, and parasitic myositis, and macrophagic myofasciitis, to be recognized. The treatment of the inflammatory myopathies remains largely empirical and relies upon the use of corticosteroids, immunosuppressive agents, and intravenous immunoglobulin, all of which have nonselective effects on the immune system. Further controlled clinical trials are required to evaluate the relative efficacy of the available therapeutic modalities particularly in combinations, and of newer immunosuppressive agents (mycophenolate mofetil and tacrolimus) and cytokine-based therapies for the treatment of resistant cases of DM, PM, and IBM. Improved understanding of the molecular mechanisms of muscle injury in the inflammatory myopathies should lead to the development of more specific forms of immunotherapy for these conditions.
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Affiliation(s)
- Frank L Mastaglia
- Centre for Neuromuscular and Neurological Disorders, University of Western Australia, Queen Elizabeth II Medical Centre, Nedlands, Australia.
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43
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Elliott PJ, Zollner TM, Boehncke WH. Proteasome inhibition: a new anti-inflammatory strategy. J Mol Med (Berl) 2003; 81:235-45. [PMID: 12700891 DOI: 10.1007/s00109-003-0422-2] [Citation(s) in RCA: 174] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2002] [Accepted: 01/07/2003] [Indexed: 10/20/2022]
Abstract
The ubiquitin-proteasome pathway has a central role in the selective degradation of intracellular proteins. Among the key proteins modulated by the proteasome are those involved in the control of inflammatory processes, cell cycle regulation, and gene expression. Consequently proteasome inhibition is a potential treatment option for cancer and inflammatory conditions. Thus far, proof of principle has been obtained from studies in numerous animal models for a variety of human diseases including cancer, reperfusion injury, and inflammatory conditions such as rheumatoid arthritis, asthma, multiple sclerosis, and psoriasis. Two proteasome inhibitors, each representing a unique chemical class, are currently under clinical evaluation. Velcade (PS-341) is currently being evaluated in multiple phase II clinical trials for several solid tumor indications and has just entered a phase III trial for multiple myeloma. PS-519, representing another class of inhibitors, focuses on the inflammatory events following ischemia and reperfusion injury. Since proteasome inhibitors exhibit anti-inflammatory and antiproliferative effects, diseases characterized by both of these processes simultaneously, as is the case in rheumatoid arthritis or psoriasis, might also represent clinical opportunities for such drugs.
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44
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Mantle D, Preedy VR. Adverse and beneficial functions of proteolytic enzymes in skeletal muscle. An overview. ADVERSE DRUG REACTIONS AND TOXICOLOGICAL REVIEWS 2002; 21:31-49. [PMID: 12140906 DOI: 10.1007/bf03256182] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Proteolytic enzymes (proteases) comprise a family of enzymes which hydrolyse protein or peptide substrates in the generalised process of intracellular protein degradation, a process essential for the normal functioning of all cells. Proteases may also have a wide range of additional functions, including metabolic control of physiologically active oligopeptides or precursor protein forms, antigen presentation/recognition by the major histocompatibility complex in the cellular immune response, as well as in digestion, blood clotting, complement activation, etc. In this article, the nomenclature and classification of proteolytic enzymes in skeletal muscle, and their role in normal muscle physiological processes have been reviewed, including exercise, muscle development and ageing. Although proteases play an important role in normal muscle functioning, in pathological situations the enzymes may themselves be regarded as 'toxic agents' in terms of their damaging effects on muscle tissue. Muscle damage resulting from inappropriate activity of proteolytic enzymes in muscle wasting associated with muscular dystrophies, denervation atrophy, inflammatory myopathies, cancer, sepsis, diabetes and alcoholism have been reviewed. In addition, evidence that the adverse effects of drugs known to induce muscle wasting, such as corticosteroids, (or beneficial effects of growth promoting drugs) may be mediated via proteolytic enzymes is also reviewed.
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Affiliation(s)
- David Mantle
- Department of Agricultural and Environmental Science, Kig George VI Building, University of Newcastle upon Tyne, Newcastle upon Tyne, NE1 7RU England
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45
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Targoff IN. Laboratory testing in the diagnosis and management of idiopathic inflammatory myopathies. Rheum Dis Clin North Am 2002; 28:859-90, viii. [PMID: 12506776 DOI: 10.1016/s0889-857x(02)00032-7] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Laboratory testing commonly used to assess the idiopathic inflammatory myopathies (IIMs) can be divided into three categories: (1) measurement of serum activities or concentrations of muscle-derived factors--such as enzymes, myoglobin, and other molecules--in order to assess muscle injury; (2) immunologic tests that detect markers of the disease process, including serum autoantibodies that have been associated with myositis; and (3) general laboratory tests that are used to assess the patient's general status and medical condition. The laboratory assessment of muscle-derived factors that reflect muscle injury, and the determination of serum autoantibodies, play valuable roles in the diagnosis and management of the IIM. Enzyme elevations do not correlate with disease activity in all patients, however, and they must be interpreted within the clinical context. Autoantibodies can identify disease subsets with distinctive patterns of clinical manifestations, genetics, responses to therapy and prognosis, but disease-specific autoantibodies are present in only half of patients with IIM. Recent studies have defined additional myositis autoantibodies that may improve our capacity to diagnose and manage the IIM.
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Affiliation(s)
- Ira N Targoff
- Department of Medicine, Veterans Affairs Medical Center, Oklahoma Medical Research Foundation, University of Oklahoma Health Sciences Center, 825 NE 13th Street, Oklahoma City, OK 73104, USA.
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Abstract
Several defined, specific autoantibodies have been associated with polymyositis and dermatomyositis. These include autoantibodies to at least six of the aminoacyl-transfer-ribonucleic-acid synthetases; to the signal recognition particle; to the protein complexes labeled Mi-2 and PM-Scl; and several autoantibodies, such as anti-U1nRNP and anti-Ro/SSA, that have recognized associations with other conditions. These autoantibodies are a continuing area of interest. Recent studies have involved the clinical implications of these autoantibodies, and their potential significance for etiology and pathogenesis of the disease. This report will review recent studies of myositis autoantibodies and their clinical associations, both extramuscular features, such as interstitial lung disease and aspects of the myositis itself. New myositis autoantibodies continue to emerge, which may have clinical utility. Several have been associated with dermatomyositis, including juvenile dermatomyositis, which has a low frequency of traditional myositis autoantibodies. There is also new information regarding the antigenic targets of anti-Mi-2 and anti-PM-Scl, two of the earliest recognized myositis autoantibodies. New evidence over the past few years has challenged old concepts of the relationship of autoantibodies to the pathogenesis of myositis, and has suggested potential new mechanisms for the origin of the associated autoantibodies. Despite this progress, the reason for production of the autoantibodies and their role in tissue injury remain unknown.
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Affiliation(s)
- Ira N Targoff
- Department of Medicine, Veterans Affairs Medical Center, Oklahoma Medical Research Foundation and University of Oklahoma Health Sciences Center, 825 NE 13th Street, Oklahoma City, OK 73104, USA.
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47
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Beyer TD, Kolowos W, Dumitriu IE, Voll RE, Heyder P, Gaipl US, Kalden JR, Herrmann M. Apoptosis of the teratocarcinoma cell line Tera-1 leads to the cleavage of HERV-K10gag proteins by caspases and/or granzyme B. Scand J Immunol 2002; 56:303-9. [PMID: 12193232 DOI: 10.1046/j.1365-3083.2002.01139.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Redistribution, post-translational modifications and coclustering with viral antigens contribute to the immunogenicity of apoptotic cell-derived autoantigens. Almost all known targets of the humoral autoimmune response in systemic lupus erythematosus (SLE) are cleaved by caspases or granzyme B during apoptosis. Antibodies against retroviral proteins can frequently be detected in the sera of SLE patients without overt retroviral infections. These antibodies may represent cross-reactive antibodies or may have been induced by proteins encoded by endogenous retroviral sequences. We used Tera-1 cells that abundantly express a group-specific antigen of human endogenous retroviruses, HERV-K10gag polyprotein, to investigate its processing during apoptosis. Tera-1 cells induced to undergo apoptosis showed an altered HERV-K10gag processing compared with viable cells. In addition, granzyme B was able to cleave HERV-K10gag isolated from viable Tera-1 cells. Similar to nuclear autoantigens, endogenous retroviral proteins are cleaved during the execution phase of apoptosis. These post-translational modifications may result in the generation of T-cell neoepitopes or a changed epitope hierarchy of retroviral proteins. Therefore, immunogenicity of retroviral antigens in SLE patients may result from a similar mechanism as described for nuclear autoantigens.
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Affiliation(s)
- T D Beyer
- Institute of Clinical Immunology and Rheumatology, Department of Internal Medicine III, Friedrich-Alexander University of Erlangen-Nuremberg, Erlangen, Germany
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48
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Nambiar MP, Enyedy EJ, Fisher CU, Krishnan S, Warke VG, Gilliland WR, Oglesby RJ, Tsokos GC. Abnormal expression of various molecular forms and distribution of T cell receptor zeta chain in patients with systemic lupus erythematosus. ARTHRITIS AND RHEUMATISM 2002; 46:163-74. [PMID: 11817588 DOI: 10.1002/1529-0131(200201)46:1<163::aid-art10065>3.0.co;2-j] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE T cells from the majority of patients with systemic lupus erythematosus (SLE) display antigen receptor-mediated signaling aberrations associated with defective T cell receptor (TCR) zeta chain expression. The TCR zeta chain, a critical signaling molecule, exists in multiple molecular forms and membrane fractions with distinct functions in antigen-mediated signaling processes. This study was undertaken to investigate the complete spectrum of expression of the different forms and distribution of the TCR zeta chain in SLE T cells. METHODS T cells were isolated from 48 SLE patients and 21 healthy subjects. The expression of various forms of the TCR zeta chain was investigated by immunoblotting with specific antibodies. The lipid raft-associated form of the zeta chain was determined by quantitating the solubilized zeta chain after disruption of the lipid rafts by cholesterol depletion using methyl-betacyclodextrin. The distribution of the zeta chain was investigated by fluorescence microscopy. RESULTS The phosphorylated 21- and 23-kd forms and the detergent-insoluble membrane-associated form of the TCR zeta chain and alternatively spliced zeta chain were significantly decreased in SLE T cells. In contrast, major ubiquitinated forms of the zeta chain were increased in these cells. We also identified up-regulation of a novel 14-kd form of the zeta chain in SLE T cells. Resting SLE T cell membranes had an increased percentage of the residual membrane-bound zeta chain in the lipid rafts. Fluorescence microscopy findings indicated that the residual zeta chain is more clustered on the cell membranes of SLE T cells. CONCLUSION These results suggest that, in addition to the 16-kd form, expression of other molecular forms and fractions of the TCR zeta chain as well as its membrane distribution are abnormal in SLE T cells. Increased lipid raft association and surface clustering of the zeta chain may explain the molecular mechanisms underlying the signaling abnormalities in these cells.
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49
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Abstract
During the last 30 years, investigation of the transcriptional and translational mechanisms of gene regulation has been a major focus of molecular cancer biology. More recently, it has become evident that cancer-related mutations and cancer-related therapies also can affect post-translational processing of cellular proteins and that control exerted at this level can be critical in defining both the cancer phenotype and the response to therapeutic intervention. One post-translational mechanism that is receiving considerable attention is degradation of intracellular proteins through the multicatalytic 26S proteasome. This follows growing recognition of the fact that protein degradation is a well-regulated and selective process that can differentially control intracellular protein expression levels. The proteasome is responsible for the degradation of all short-lived proteins and 70-90% of all long-lived proteins, thereby regulating signal transduction through pathways involving factors such as AP1 and NFKB, and processes such as cell cycle progression and arrest, DNA transcription, DNA repair/misrepair, angiogenesis, apoptosis/survival, growth and development, and inflammation and immunity, as well as muscle wasting (e.g. in cachexia and sepsis). In this review, we discuss the potential involvement of the proteasome in both cancer biology and cancer treatment.
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Affiliation(s)
- F Pajonk
- Department of Radiation Therapy, Radiological University Clinic, Hugstetter Str. 55, 79106 Freiburg i. Brsg., Germany.
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50
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Abstract
The proteasome is an enzyme present in all cells, from yeast to human, and has a central role in the proteolytic degradation of the vast majority of intracellular proteins. Among the key proteins modulated by the proteasome are those involved in controlling inflammatory processes, cell cycle regulation, and gene expression. As such, agents that inhibit the proteasome have been shown to be active in numerous animal models of inflammation and cancer Two proteasome inhibitors are under clinical evaluation. PS-519 is being studied for the treatment of reperfusion injury that occurs following cerebral ischemia and myocardial infarction. The other, PS-341, has recently entered multiple phase 2 clinical trials for the treatment of multiple myeloma, chronic lymphocytic leukemia, and a variety of solid tumors. The proteasome may have an important role in the evolution of HIV-related disorders including AIDS and inflammatory disorders. Therapeutic strategies using proteasome inhibitors for the treatment of these conditions have now entered preclinical development.
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Affiliation(s)
- P J Elliott
- Millennium Pharmaceuticals, Cambridge, MA, USA
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