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I2CT
Immunologie, Immunopathologie et Chimie Thérapeutique
Publications
2009
Schett G, Dumortier H, Hoefler E, Muller S, Steiner G
B cell epitopes of the heterogeneous nuclear ribonucleoprotein A2: identification of a new specific antibody marker for active lupus disease Article de journal
Dans: Annals of the Rheumatic Diseases, vol. 68, non 5, p. 729–735, 2009, ISSN: 1468-2060.
Résumé | Liens | BibTeX | Étiquettes: Autoantibodies, B-Lymphocyte, Biomarkers, Dumortier, Enzyme-Linked Immunosorbent Assay, Epitopes, Female, Follow-Up Studies, Heterogeneous-Nuclear Ribonucleoprotein Group A-B, Humans, I2CT, Lupus Erythematosus, Male, Rheumatic Diseases, Severity of Illness Index, Systemic, Team-Dumortier
@article{schett_b_2009,
title = {B cell epitopes of the heterogeneous nuclear ribonucleoprotein A2: identification of a new specific antibody marker for active lupus disease},
author = {G Schett and H Dumortier and E Hoefler and S Muller and G Steiner},
doi = {10.1136/ard.2007.087502},
issn = {1468-2060},
year = {2009},
date = {2009-05-01},
journal = {Annals of the Rheumatic Diseases},
volume = {68},
number = {5},
pages = {729--735},
abstract = {OBJECTIVES: Autoantibody formation and T cell reactivity against the heterogeneous nuclear ribonucleoprotein A2 (hnRNP-A2) has been observed in patients with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). Since no differences in epitope recognition were reported and the usefulness of anti-hnRNP-A2 antibodies as diagnostic markers of SLE is unknown, it was our objective to characterise linear B cell epitopes of hnRNP-A2 and to relate the anti-hnRNP-A2 antibody responses to disease activity and clinical features of SLE.
METHODS: Sequential serum samples from 15 patients with SLE and sera from patients with other rheumatic diseases and healthy subjects were investigated by ELISA for autoantibody reactivities against a set of 13 overlapping peptides spanning the RNA-binding region of hnRNP-A2. Antibody reactivity against the complete protein was determined by western immunoblotting and ELISA. SLE disease activity was assessed by European Consensus Lupus Activity Measure scores, by SLE Index scores and the British Isles Lupus Assessment index.
RESULTS: Anti-peptide antibody reactivities were found in 60% of SLE sera but in only 5% of control samples, and were mainly directed to four peptides, one of which (p155-175) appeared to be immunodominant. Antibodies to p155-175 were exclusively seen in patients with SLE and correlated with clinical disease activity as well as kidney and skin involvement. No correlations were found for the other anti-peptide antibody responses.
CONCLUSION: Peptide p155-175 encompasses a disease-specific immunodominant epitope of hnRNP-A2. Since antibodies to p155-175 correlate with disease activity and nephritis, they may be useful as markers for active SLE.},
keywords = {Autoantibodies, B-Lymphocyte, Biomarkers, Dumortier, Enzyme-Linked Immunosorbent Assay, Epitopes, Female, Follow-Up Studies, Heterogeneous-Nuclear Ribonucleoprotein Group A-B, Humans, I2CT, Lupus Erythematosus, Male, Rheumatic Diseases, Severity of Illness Index, Systemic, Team-Dumortier},
pubstate = {published},
tppubtype = {article}
}
OBJECTIVES: Autoantibody formation and T cell reactivity against the heterogeneous nuclear ribonucleoprotein A2 (hnRNP-A2) has been observed in patients with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). Since no differences in epitope recognition were reported and the usefulness of anti-hnRNP-A2 antibodies as diagnostic markers of SLE is unknown, it was our objective to characterise linear B cell epitopes of hnRNP-A2 and to relate the anti-hnRNP-A2 antibody responses to disease activity and clinical features of SLE.
METHODS: Sequential serum samples from 15 patients with SLE and sera from patients with other rheumatic diseases and healthy subjects were investigated by ELISA for autoantibody reactivities against a set of 13 overlapping peptides spanning the RNA-binding region of hnRNP-A2. Antibody reactivity against the complete protein was determined by western immunoblotting and ELISA. SLE disease activity was assessed by European Consensus Lupus Activity Measure scores, by SLE Index scores and the British Isles Lupus Assessment index.
RESULTS: Anti-peptide antibody reactivities were found in 60% of SLE sera but in only 5% of control samples, and were mainly directed to four peptides, one of which (p155-175) appeared to be immunodominant. Antibodies to p155-175 were exclusively seen in patients with SLE and correlated with clinical disease activity as well as kidney and skin involvement. No correlations were found for the other anti-peptide antibody responses.
CONCLUSION: Peptide p155-175 encompasses a disease-specific immunodominant epitope of hnRNP-A2. Since antibodies to p155-175 correlate with disease activity and nephritis, they may be useful as markers for active SLE.
METHODS: Sequential serum samples from 15 patients with SLE and sera from patients with other rheumatic diseases and healthy subjects were investigated by ELISA for autoantibody reactivities against a set of 13 overlapping peptides spanning the RNA-binding region of hnRNP-A2. Antibody reactivity against the complete protein was determined by western immunoblotting and ELISA. SLE disease activity was assessed by European Consensus Lupus Activity Measure scores, by SLE Index scores and the British Isles Lupus Assessment index.
RESULTS: Anti-peptide antibody reactivities were found in 60% of SLE sera but in only 5% of control samples, and were mainly directed to four peptides, one of which (p155-175) appeared to be immunodominant. Antibodies to p155-175 were exclusively seen in patients with SLE and correlated with clinical disease activity as well as kidney and skin involvement. No correlations were found for the other anti-peptide antibody responses.
CONCLUSION: Peptide p155-175 encompasses a disease-specific immunodominant epitope of hnRNP-A2. Since antibodies to p155-175 correlate with disease activity and nephritis, they may be useful as markers for active SLE.
2005
Hayer Silvia, Tohidast-Akrad Makiyeh, Haralambous Silva, Jahn-Schmid Beatrice, Skriner Karl, Trembleau Sylvie, Dumortier Hélène, Pinol-Roma Serafin, Redlich Kurt, Schett Georg, Muller Sylviane, Kollias George, Smolen Josef, Steiner Günter
Dans: Journal of Immunology (Baltimore, Md.: 1950), vol. 175, non 12, p. 8327–8336, 2005, ISSN: 0022-1767.
Résumé | Liens | BibTeX | Étiquettes: Animals, Antibody Formation, arthritis, Autoantibodies, Autoantigens, Dumortier, Gene Expression Regulation, Heterogeneous-Nuclear Ribonucleoprotein Group A-B, Humans, I2CT, Joints, Mice, rheumatoid, Team-Dumortier, Tissue Distribution, transgenic, Tumor Necrosis Factor-alpha
@article{hayer_aberrant_2005,
title = {Aberrant expression of the autoantigen heterogeneous nuclear ribonucleoprotein-A2 (RA33) and spontaneous formation of rheumatoid arthritis-associated anti-RA33 autoantibodies in TNF-alpha transgenic mice},
author = {Silvia Hayer and Makiyeh Tohidast-Akrad and Silva Haralambous and Beatrice Jahn-Schmid and Karl Skriner and Sylvie Trembleau and Hélène Dumortier and Serafin Pinol-Roma and Kurt Redlich and Georg Schett and Sylviane Muller and George Kollias and Josef Smolen and Günter Steiner},
doi = {10.4049/jimmunol.175.12.8327},
issn = {0022-1767},
year = {2005},
date = {2005-12-01},
journal = {Journal of Immunology (Baltimore, Md.: 1950)},
volume = {175},
number = {12},
pages = {8327--8336},
abstract = {Human TNF-alpha transgenic (hTNFtg) mice develop erosive arthritis closely resembling rheumatoid arthritis (RA). To investigate mechanisms leading to pathological autoimmune reactions in RA, we examined hTNFtg animals for the presence of RA-associated autoantibodies including Abs to citrullinated epitopes (anti-cyclic citrullinated peptide), heterogeneous nuclear ribonucleoprotein (hnRNP)-A2 (anti-RA33), and heat shock proteins (hsp) (anti-hsp). Although IgM anti-hsp Abs were detected in 40% of hTNFtg and control mice, IgG anti-hsp Abs were rarely seen, and anti-cyclic citrullinated peptide Abs were not seen at all. In contrast, textgreater50% of hTNFtg mice showed IgG anti-RA33 autoantibodies, which became detectable shortly after the onset of arthritis. These Abs were predominantly directed to a short epitope, which was identical with an epitope previously described in MRL/lpr mice. Incidence of anti-RA33 was significantly decreased in mice treated with the osteoclast inhibitor osteoprotegerin and also in c-fos-deficient mice lacking osteoclasts. Pronounced expression of hnRNP-A2 and a smaller splice variant was seen in joints of hTNFtg mice, whereas expression was low in control animals. Although the closely related hnRNP-A1 was also overexpressed, autoantibodies to this protein were infrequently detected. Because expression of hnRNP-A2 in thymus, spleen, brain, and lung was similar in hTNFtg and control mice, aberrant expression appeared to be restricted to the inflamed joint. Finally, immunization of hTNFtg mice with recombinant hnRNP-A2 or a peptide harboring the major B cell epitope aggravated arthritis. These findings suggest that overproduction of TNF-alpha leads to aberrant expression of hnRNP-A2 in the rheumatoid joint and subsequently to autoimmune reactions, which may enhance the inflammatory and destructive process.},
keywords = {Animals, Antibody Formation, arthritis, Autoantibodies, Autoantigens, Dumortier, Gene Expression Regulation, Heterogeneous-Nuclear Ribonucleoprotein Group A-B, Humans, I2CT, Joints, Mice, rheumatoid, Team-Dumortier, Tissue Distribution, transgenic, Tumor Necrosis Factor-alpha},
pubstate = {published},
tppubtype = {article}
}
Human TNF-alpha transgenic (hTNFtg) mice develop erosive arthritis closely resembling rheumatoid arthritis (RA). To investigate mechanisms leading to pathological autoimmune reactions in RA, we examined hTNFtg animals for the presence of RA-associated autoantibodies including Abs to citrullinated epitopes (anti-cyclic citrullinated peptide), heterogeneous nuclear ribonucleoprotein (hnRNP)-A2 (anti-RA33), and heat shock proteins (hsp) (anti-hsp). Although IgM anti-hsp Abs were detected in 40% of hTNFtg and control mice, IgG anti-hsp Abs were rarely seen, and anti-cyclic citrullinated peptide Abs were not seen at all. In contrast, textgreater50% of hTNFtg mice showed IgG anti-RA33 autoantibodies, which became detectable shortly after the onset of arthritis. These Abs were predominantly directed to a short epitope, which was identical with an epitope previously described in MRL/lpr mice. Incidence of anti-RA33 was significantly decreased in mice treated with the osteoclast inhibitor osteoprotegerin and also in c-fos-deficient mice lacking osteoclasts. Pronounced expression of hnRNP-A2 and a smaller splice variant was seen in joints of hTNFtg mice, whereas expression was low in control animals. Although the closely related hnRNP-A1 was also overexpressed, autoantibodies to this protein were infrequently detected. Because expression of hnRNP-A2 in thymus, spleen, brain, and lung was similar in hTNFtg and control mice, aberrant expression appeared to be restricted to the inflamed joint. Finally, immunization of hTNFtg mice with recombinant hnRNP-A2 or a peptide harboring the major B cell epitope aggravated arthritis. These findings suggest that overproduction of TNF-alpha leads to aberrant expression of hnRNP-A2 in the rheumatoid joint and subsequently to autoimmune reactions, which may enhance the inflammatory and destructive process.
2001
Monneaux F, Dumortier H, Steiner G, Briand J P, Muller S
Murine models of systemic lupus erythematosus: B and Ŧ cell responses to spliceosomal ribonucleoproteins in MRL/Fas(lpr) and (NZB x NZW)F(1) lupus mice Article de journal
Dans: International Immunology, vol. 13, non 9, p. 1155–1163, 2001, ISSN: 0953-8178.
Résumé | Liens | BibTeX | Étiquettes: Animals, Antibody Specificity, B-Lymphocytes, Crosses, Dumortier, fas Receptor, Female, Genetic, Heterogeneous-Nuclear Ribonucleoprotein Group A-B, Heterogeneous-Nuclear Ribonucleoproteins, Histocompatibility Antigens Class II, I2CT, Immunoglobulin G, Inbred MRL lpr, Inbred NZB, Lupus Erythematosus, Mice, Monneaux, Peptide Fragments, Ribonucleoprotein, Ribonucleoproteins, Small Nuclear, Species Specificity, Spliceosomes, Systemic, T-Lymphocytes, Team-Dumortier, U1 Small Nuclear
@article{monneaux_murine_2001,
title = {Murine models of systemic lupus erythematosus: B and Ŧ cell responses to spliceosomal ribonucleoproteins in MRL/Fas(lpr) and (NZB x NZW)F(1) lupus mice},
author = {F Monneaux and H Dumortier and G Steiner and J P Briand and S Muller},
doi = {10.1093/intimm/13.9.1155},
issn = {0953-8178},
year = {2001},
date = {2001-01-01},
journal = {International Immunology},
volume = {13},
number = {9},
pages = {1155--1163},
abstract = {(NZB x NZW)F(1) and MRL/Fas(lpr) lupus mice present a similar phenotype with a spectrum of autoantibodies associated with very severe nephritis. It is thought, however, that in contrast to other lupus-prone mice such as MRL/Fas(lpr) mice, (NZB x NZW)F(1) mice do not generate autoantibodies to ribonucleoproteins (RNP) Sm/RNP. In this study, we demonstrate that contrary to previous reports, the autoimmune response directed against Sm/RNP antigens also occurs in NZB x NZW mice. CD4(+) T cells from unprimed 10-week-old NZB x NZW mice proliferate and secrete IL-2 in response to peptide 131-151 of the U1-70K protein, which is known to contain a T(h) epitope recognized by CD4(+) T cells from MRL/Fas(lpr) mice. Peptide 131-151, which was found to bind I-A(k) and I-E(k) class II MHC molecules, also bound both I-A(d) and I-E(d) molecules. This result led us to also re-evaluate longitudinally the anti-Sm/RNP antibody response in NZB x NZW mice. We found that 25-week-old mice do produce antibodies reacting with several small nuclear and heterogeneous nuclear (hn) RNP proteins, such as SmD1, U1-70K and hnRNP A2/B1 proteins. The fine specificity of these antibodies was studied with overlapping synthetic peptides. The same antigenically positive and negative peptides were characterized in MRL/Fas(lpr) and NZB x NZW mice in the three proteins. This new finding can help to understand the mechanisms involved in the development of the anti-Sm/RNP antibody response and, particularly, the role played by non-MHC genes in this autoimmune response.},
keywords = {Animals, Antibody Specificity, B-Lymphocytes, Crosses, Dumortier, fas Receptor, Female, Genetic, Heterogeneous-Nuclear Ribonucleoprotein Group A-B, Heterogeneous-Nuclear Ribonucleoproteins, Histocompatibility Antigens Class II, I2CT, Immunoglobulin G, Inbred MRL lpr, Inbred NZB, Lupus Erythematosus, Mice, Monneaux, Peptide Fragments, Ribonucleoprotein, Ribonucleoproteins, Small Nuclear, Species Specificity, Spliceosomes, Systemic, T-Lymphocytes, Team-Dumortier, U1 Small Nuclear},
pubstate = {published},
tppubtype = {article}
}
(NZB x NZW)F(1) and MRL/Fas(lpr) lupus mice present a similar phenotype with a spectrum of autoantibodies associated with very severe nephritis. It is thought, however, that in contrast to other lupus-prone mice such as MRL/Fas(lpr) mice, (NZB x NZW)F(1) mice do not generate autoantibodies to ribonucleoproteins (RNP) Sm/RNP. In this study, we demonstrate that contrary to previous reports, the autoimmune response directed against Sm/RNP antigens also occurs in NZB x NZW mice. CD4(+) T cells from unprimed 10-week-old NZB x NZW mice proliferate and secrete IL-2 in response to peptide 131-151 of the U1-70K protein, which is known to contain a T(h) epitope recognized by CD4(+) T cells from MRL/Fas(lpr) mice. Peptide 131-151, which was found to bind I-A(k) and I-E(k) class II MHC molecules, also bound both I-A(d) and I-E(d) molecules. This result led us to also re-evaluate longitudinally the anti-Sm/RNP antibody response in NZB x NZW mice. We found that 25-week-old mice do produce antibodies reacting with several small nuclear and heterogeneous nuclear (hn) RNP proteins, such as SmD1, U1-70K and hnRNP A2/B1 proteins. The fine specificity of these antibodies was studied with overlapping synthetic peptides. The same antigenically positive and negative peptides were characterized in MRL/Fas(lpr) and NZB x NZW mice in the three proteins. This new finding can help to understand the mechanisms involved in the development of the anti-Sm/RNP antibody response and, particularly, the role played by non-MHC genes in this autoimmune response.
2000
Dumortier H, Monneaux F, Jahn-Schmid B, Briand J P, Skriner K, Cohen P L, Smolen J S, Steiner G, Muller S
B and Ŧ cell responses to the spliceosomal heterogeneous nuclear ribonucleoproteins A2 and B1 in normal and lupus mice Article de journal
Dans: Journal of Immunology (Baltimore, Md.: 1950), vol. 165, non 4, p. 2297–2305, 2000, ISSN: 0022-1767.
Résumé | Liens | BibTeX | Étiquettes: Amino Acid Sequence, Animals, Autoantibodies, B-Lymphocytes, Dumortier, Epitope Mapping, Female, Heterogeneous Nuclear, Heterogeneous-Nuclear Ribonucleoprotein Group A-B, Heterogeneous-Nuclear Ribonucleoproteins, Humans, I2CT, Immunoglobulin G, Inbred BALB C, Inbred C57BL, Inbred CBA, Inbred MRL lpr, Injections, Lupus Nephritis, Lymphocyte Activation, Male, Mice, Molecular Sequence Data, Monneaux, Peptide Fragments, Recombinant Proteins, Ribonucleoproteins, RNA, Spliceosomes, Subcutaneous, T-Lymphocytes, Team-Dumortier, transgenic
@article{dumortier_b_2000,
title = {B and Ŧ cell responses to the spliceosomal heterogeneous nuclear ribonucleoproteins A2 and B1 in normal and lupus mice},
author = {H Dumortier and F Monneaux and B Jahn-Schmid and J P Briand and K Skriner and P L Cohen and J S Smolen and G Steiner and S Muller},
doi = {10.4049/jimmunol.165.4.2297},
issn = {0022-1767},
year = {2000},
date = {2000-08-01},
journal = {Journal of Immunology (Baltimore, Md.: 1950)},
volume = {165},
number = {4},
pages = {2297--2305},
abstract = {Autoantibodies directed against spliceosomal heterogeneous nuclear ribonucleoproteins (hnRNPs) are a typical feature of rheumatoid arthritis, systemic lupus erythematosus, and mixed-connective tissue disease. With the aim of investigating a potential pathogenic role of these Abs, we have studied the Ab response to A2/B1 hnRNPs in different murine models of lupus. The specificity of anti-A2/B1 Abs was tested with a series of 14 overlapping synthetic peptides covering the region 1-206 of A2 that contains most of the epitopes recognized by patients' Abs. A major epitope recognized very early during the course of the disease by Abs from most of MRL lpr/lpr mice but not from other lupus mice and from mice of different MHC haplotypes immunized against B1 was identified in residues 50-70. This peptide contains a highly conserved sequence RGFGFVTF also present in other hnRNPs and small nuclear ribonucleoproteins. Abs reacting with a second A2 epitope identified in residues 35-55 were detectable several weeks later, suggesting an intramolecular B cell epitope spreading during the course of the disease. We identified several T cell epitopes within the region 35-175 that generated an effective Th cell response with IL-2 and IFN-gamma secretion in nonautoimmune CBA/J mice sharing the same MHC haplotype H-2k as MRL/lpr mice. None of the peptides stimulated T cells primed in vivo with B1. Because Abs to peptide 50-70 were detected significantly earlier than Abs reacting with other A2 peptides and the protein itself, it is possible that within the protein, this segment contains residues playing an initiator role in the induction of the anti-A2/B1 and antispliceosome Ab response.},
keywords = {Amino Acid Sequence, Animals, Autoantibodies, B-Lymphocytes, Dumortier, Epitope Mapping, Female, Heterogeneous Nuclear, Heterogeneous-Nuclear Ribonucleoprotein Group A-B, Heterogeneous-Nuclear Ribonucleoproteins, Humans, I2CT, Immunoglobulin G, Inbred BALB C, Inbred C57BL, Inbred CBA, Inbred MRL lpr, Injections, Lupus Nephritis, Lymphocyte Activation, Male, Mice, Molecular Sequence Data, Monneaux, Peptide Fragments, Recombinant Proteins, Ribonucleoproteins, RNA, Spliceosomes, Subcutaneous, T-Lymphocytes, Team-Dumortier, transgenic},
pubstate = {published},
tppubtype = {article}
}
Autoantibodies directed against spliceosomal heterogeneous nuclear ribonucleoproteins (hnRNPs) are a typical feature of rheumatoid arthritis, systemic lupus erythematosus, and mixed-connective tissue disease. With the aim of investigating a potential pathogenic role of these Abs, we have studied the Ab response to A2/B1 hnRNPs in different murine models of lupus. The specificity of anti-A2/B1 Abs was tested with a series of 14 overlapping synthetic peptides covering the region 1-206 of A2 that contains most of the epitopes recognized by patients' Abs. A major epitope recognized very early during the course of the disease by Abs from most of MRL lpr/lpr mice but not from other lupus mice and from mice of different MHC haplotypes immunized against B1 was identified in residues 50-70. This peptide contains a highly conserved sequence RGFGFVTF also present in other hnRNPs and small nuclear ribonucleoproteins. Abs reacting with a second A2 epitope identified in residues 35-55 were detectable several weeks later, suggesting an intramolecular B cell epitope spreading during the course of the disease. We identified several T cell epitopes within the region 35-175 that generated an effective Th cell response with IL-2 and IFN-gamma secretion in nonautoimmune CBA/J mice sharing the same MHC haplotype H-2k as MRL/lpr mice. None of the peptides stimulated T cells primed in vivo with B1. Because Abs to peptide 50-70 were detected significantly earlier than Abs reacting with other A2 peptides and the protein itself, it is possible that within the protein, this segment contains residues playing an initiator role in the induction of the anti-A2/B1 and antispliceosome Ab response.