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Autoreactive B cell responses targeting nuclear antigens in systemic sclerosis: Implications for disease pathogenesis. Semin Arthritis Rheum 2023; 58:152136. [PMID: 36403538 DOI: 10.1016/j.semarthrit.2022.152136] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 11/01/2022] [Accepted: 11/04/2022] [Indexed: 11/16/2022]
Abstract
A hallmark of disease pathogenesis of systemic sclerosis (SSc) is the presence of autoreactive B cell responses targeting nuclear proteins. Almost all SSc-patients harbour circulating antinuclear autoantibodies of which anti-topoisomerase 1, anti-centromere protein, anti-RNA polymerase III and anti-fibrillarin autoantibodies (ATA, ACA, ARA and AFA, respectively) are the most common and specific for SSc. In clinical practice, autoantibodies serve as diagnostic biomarkers and can aid in the identification of clinical phenotypes of the disease. However, factors driving disease progression in SSc are still poorly understood, and it is difficult to predict disease trajectories in individual patients. Moreover, treatment decisions remain rather empirical, with variable response rates in clinical trials due to patient heterogeneity. Current evidence has indicated that certain patients may benefit from B cell targeting therapies. Hence, it is important to understand the contribution of the antinuclear autoantibodies and their underlying B cell response to the disease pathogenesis of SSc.
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Mouse Models of Skin Fibrosis. Methods Mol Biol 2021; 2299:371-383. [PMID: 34028755 DOI: 10.1007/978-1-0716-1382-5_25] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/14/2023]
Abstract
Systemic sclerosis (SSc) is a rare systemic autoimmune disease associated with a high mortality. The first histopathological hallmarks are vasculopathy and inflammation, followed by fibrosis of the skin and internal organs. The molecular and cellular mechanisms are incompletely understood. Rodent models provide important insights into the pathogenesis of SSc and are a mainstay for the development of novel targeted therapies. Here we describe the mechanistic insights of inducible and genetic models, and also discuss in detail the limitations and pitfalls of the most frequently used SSc mouse models. We also describe protocols for running the established bleomycin-induced scleroderma skin fibrosis model.
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Abstract
Systemic sclerosis (SSc) is a connective tissue disease of unknown etiology that is characterized by fibrosis of the skin and several internal organs, vasculopathy, inflammation and autoimmunity. Animal models have improved our understanding of the pathogenesis of SSc. Many inducible and genetic animal models of SSc have been developed and characterized in the last years. All of these models have different strengths and limitations and mimic different aspects of the pathogenesis of SSc. The purpose of this review is to summarize the characteristics of the various animal models of SSc and to provide an outline of how to use these models to study certain aspects in the pathogenesis of SSc and to test the effects of potential therapeutic approaches.
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Tsujino K, Sheppard D. Critical Appraisal of the Utility and Limitations of Animal Models of Scleroderma. Curr Rheumatol Rep 2015; 18:4. [DOI: 10.1007/s11926-015-0553-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Beyer C, Schett G, Distler O, Distler JHW. Animal models of systemic sclerosis: prospects and limitations. ACTA ACUST UNITED AC 2010; 62:2831-44. [PMID: 20617524 DOI: 10.1002/art.27647] [Citation(s) in RCA: 118] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Richard V, Solans V, Favre J, Henry JP, Lallemand F, Thuillez C, Marie I. Role of endogenous endothelin in endothelial dysfunction in murine model of systemic sclerosis: tight skin mice 1. Fundam Clin Pharmacol 2009; 22:649-55. [PMID: 19049669 DOI: 10.1111/j.1472-8206.2008.00634.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Systemic sclerosis (SSc) is a systemic inflammatory disorder, resulting in severe vascular dysfunction. The endothelin (ET) system has vasoconstrictor and profibrotic properties and has been shown to be activated in SSc. ET antagonists are currently used in SSc-related pulmonary arterial hypertension, but the endothelial impact of ET antagonists remains less known in SSc. We thus assessed the effects of the dual ET(A)-ET(B) antagonist, bosentan, on endothelial dysfunction in a murine model of SSc, the heterozygous tight-skin mice 1 (TSK1(+)). Six-week-old TSK1(+) were either untreated or treated for 6 weeks with bosentan (100 mg/kg/day), and compared with controls. Endothelial function was evaluated in isolated mesenteric resistance arteries, using a small vessel myograph. TSK1(+) displayed endothelial dysfunction, as shown by a decreased response of mesenteric arteries to acetylcholine, especially in the presence of L-nitro-arginine methyl ester (L-NAME), corresponding to NO-independent, prostaglandin-mediated relaxation. The NO-independent relaxation was partially restored in bosentan-treated TSK1(+), and this was abolished by a cyclo-oxygenase inhibitor. Therefore, the murine model of SSc, TSK1(+) exhibits severe endothelial dysfunction of peripheral resistance arteries. The ET antagonist bosentan prevents endothelial alterations, suggesting a major role of ET in the adverse vascular effects of SSc.
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Affiliation(s)
- Vincent Richard
- Inserm U644 & Rouen University Hospital, Institute for Biomedical Research and IFRMP 23, University of Rouen, Rouen, France.
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Hansson M, Abedi-Valugerdi M. Mercuric chloride induces a strong immune activation, but does not accelerate the development of dermal fibrosis in tight skin 1 mice. Scand J Immunol 2004; 59:469-77. [PMID: 15140057 DOI: 10.1111/j.0300-9475.2004.01415.x] [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] [Indexed: 11/29/2022]
Abstract
In susceptible mice, mercuric chloride induces a systemic autoimmune disease characterized by increased serum levels of immunoglobulin (Ig) G1 and IgE, production of anti-nucleolar autoantibodies (ANolA) and formation of renal IgG deposits. We have previously hypothesized that mercury confers more adverse immunological effects on those mouse strains, which are genetically prone to develop spontaneous autoimmune diseases than on normal strains. In this study, we tested our hypothesis in tight skin 1 (Tsk1/+) mice, a murine model for human scleroderma. As a support for our hypothesis, we observed that in Tsk1/+ mice, B cells were spontaneously hyperactive and that treatment with mercury induced a strong immune/autoimmune response in these mice, but not in their non-Tsk (+/+) littermates. This response was characterized by the formation of high numbers of splenic IgG1, IgG2b and IgG3 antibody-secreting cells, increased serum levels of IgE, production of IgG1 antibodies against single-stranded DNA (ssDNA), trinitrophenol (TNP) as well as thyroglobulin and the development of renal IgG1 deposits. Neither Tsk1/+ mice nor F1 hybrid crosses between this strain, and mercury susceptible B10.S (H-2(s)) were able to produce IgG1-ANolA in response to mercury. Moreover, mercury-induced immune activation in Tsk1/+ was not able to potentiate the progression of skin fibrosis in this strain. Thus, exposure to mercury accelerates the immune dysregulation, but not the development of skin fibrosis in Tsk1/+ mice.
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Affiliation(s)
- M Hansson
- Department of Immunology, The Wenner-Gren Institute, Arrhenius Laboratories for the Natural Sciences, Stockholm University, Stockholm, Sweden
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8
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Marie I, Bény JL. Endothelial dysfunction in murine model of systemic sclerosis: tight-skin mice 1. J Invest Dermatol 2002; 119:1379-87. [PMID: 12485443 DOI: 10.1046/j.1523-1747.2002.19614.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We conducted this study to analyze endothelial cell function within intact thoracic aorta of the systemic sclerosis murine model, the heterozygous tight-skin mice 1: (i) assessing the distribution and activation intensity of endothelial cells, responsive to endothelium-dependent vasodilators (acetylcholine, adenosine triphosphate, bradykinin, and substance P) and Iloprost, using laser line confocal microscopy in combination with two Ca2+ fluorescent dyes; (ii) evaluating en-dothelium-dependent vasodilator- and Iloprostinduced relaxation, using isometric tension measurement; and (iii) investigating the role of nitric oxide in mediating relaxation to acetylcholine and adenosine triphosphate. The number of activated endothelial cells was significantly lower in heterozygous tight-skin mice 1, compared with controls, for adenosine triphosphate and Iloprost. Maximal increase of Ca2+ fluorescence intensity ratio in activated endothelial cells was decreased for adenosine triphosphate, bradykinin, and Iloprost, in heterozygous tight-skin mice 1. Adenosine triphosphate- and Iloprost-mediated aortic relaxation was further impaired in heterozygous tight-skin mice 1. Finally, aortic relaxation to acetylcholine and adenosine triphosphate was markedly decreased by nitric oxide synthase inhibitor in heterozygous tight-skin mice 1. This study suggests that endothelial cell receptors for endothelium-dependent vasodilators and Iloprost may not be homogeneously distributed or continuously expressed in thoracic aorta of heterozygous tight-skin mice 1, resulting in endothelium-dependent vasodilatation dysfunction. Moreover, because endothelium-dependent relaxation was highly dependent on nitric oxide release in heterozygous tight-skin mice 1, endothelium-dependent relaxation may differ from that of controls by increased production of nitric oxide. In turn, in heterozygous tight-skin mice 1, the resulting elevated nitric oxide levels may contribute to nitric oxide-mediated free radical endothelial cytotoxicity, although endothelium impairment may be related to other factors, particularly: Fbn-1 gene mutation and transforming growth factor-beta.
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MESH Headings
- Acetylcholine/pharmacology
- Adenosine Triphosphate/pharmacology
- Animals
- Aorta, Thoracic/physiopathology
- Bradykinin/pharmacology
- Calcium/metabolism
- Disease Models, Animal
- Endothelium, Vascular/metabolism
- Endothelium, Vascular/physiopathology
- Iloprost/pharmacology
- In Vitro Techniques
- Isometric Contraction/drug effects
- Mice
- Mice, Inbred C57BL
- Mice, Mutant Strains
- Microscopy, Confocal
- Nitric Oxide/metabolism
- Nitric Oxide Synthase/antagonists & inhibitors
- Scleroderma, Systemic/genetics
- Scleroderma, Systemic/metabolism
- Scleroderma, Systemic/physiopathology
- Skin/pathology
- Substance P/pharmacology
- Vasodilation/drug effects
- Vasodilation/physiology
- Vasodilator Agents/pharmacology
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Affiliation(s)
- I Marie
- Department of Zoology and Animal Biology, University of Geneva, Sciences III, 30 Quai Ernest Ansermet, 1211 Geneva 4, Switzerland.
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Abstract
Animal models of systemic connective tissue diseases have provided valuable insights into the causative mechanisms and the pathogenesis of these diseases, and have provided the means to test potentially useful therapeutic interventions. Although numerous animal models for systemic sclerosis (SSc) have been described, the most extensively studied are murine. One advantage of murine animal models is the large body of genetic information available for the mouse that is not available for other species. No animal model described to date reproduces precisely all manifestations of SSc. However, all animal models display tissue fibrotic changes similar to those present in SSc. The prudent interpretation of the results obtained from the study of animal models has provided substantial and valuable information about the pathogenesis of the human disease.
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Affiliation(s)
- Sergio A Jimenez
- Department of Medicine, Jefferson Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA.
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Dodig TD, Mack KT, Cassarino DF, Clark SH. Development of the tight-skin phenotype in immune-deficient mice. ARTHRITIS AND RHEUMATISM 2001; 44:723-7. [PMID: 11263788 DOI: 10.1002/1529-0131(200103)44:3<723::aid-anr122>3.0.co;2-v] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE To determine if cutaneous thickening, a major phenotypic feature of the tight-skin (Tsk) mutation, could develop in an immune-deficient mouse. METHODS Experimental crosses among different strains of mice were conducted to create mice that were genetically Tsk/+, and that were also homozgyous for a mutation at the Prkdc(scid) locus and thus lacked mature T and B lymphocytes. Skin samples prepared from experimental and control genotypic groups of mice were evaluated for skin thickness. RESULTS The data showed that the Tsk/+ mice developed the Tsk phenotype in the absence of a functional immune system. CONCLUSION Mature T and B cells are not required for the development of the cutaneous thickening in mice carrying the Tsk mutation.
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Affiliation(s)
- T D Dodig
- Veterans Affairs Connecticut Healthcare System, Newington, USA
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Machado C, Andrew DJ. Titin as a chromosomal protein. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2001; 481:221-32; discussion 232-6. [PMID: 10987075 DOI: 10.1007/978-1-4615-4267-4_13] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
We identified titin as a chromosomal protein using a human autoimmune scleroderma serum. We cloned the corresponding gene in the fruitfly, Drosophila melanogaster. We have demonstrated that titin is not only expressed and localized in striated muscle but is also distributed uniformly on condensed mitotic chromosomes using multiple antibodies directed against different domains of both Drosophila and vertebrate titin. Titin is a giant sarcomeric protein responsible for the elasticity of striated muscle. Titin may also function as a molecular scaffold during myofibril assembly. We hypothesize that titin is a component of chromosomes that may function to determine chromosome structure and provide elasticity, playing a role similar to that proposed for titin in muscle. We have identified mutations in Drosophila Titin (D-Titin) and are characterizing phenotypes in muscle and chromosomes.
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Affiliation(s)
- C Machado
- Department of Cell Biology and Anatomy, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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Machado C, Sunkel CE, Andrew DJ. Human autoantibodies reveal titin as a chromosomal protein. J Cell Biol 1998; 141:321-33. [PMID: 9548712 PMCID: PMC2148454 DOI: 10.1083/jcb.141.2.321] [Citation(s) in RCA: 106] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/1997] [Revised: 02/02/1998] [Indexed: 02/07/2023] Open
Abstract
Assembly of the higher-order structure of mitotic chromosomes is a prerequisite for proper chromosome condensation, segregation and integrity. Understanding the details of this process has been limited because very few proteins involved in the assembly of chromosome structure have been discovered. Using a human autoimmune scleroderma serum that identifies a chromosomal protein in human cells and Drosophila embryos, we cloned the corresponding Drosophila gene that encodes the homologue of vertebrate titin based on protein size, sequence similarity, developmental expression and subcellular localization. Titin is a giant sarcomeric protein responsible for the elasticity of striated muscle that may also function as a molecular scaffold for myofibrillar assembly. Molecular analysis and immunostaining with antibodies to multiple titin epitopes indicates that the chromosomal and muscle forms of titin may vary in their NH2 termini. The identification of titin as a chromosomal component provides a molecular basis for chromosome structure and elasticity.
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Affiliation(s)
- C Machado
- Department of Cell Biology and Anatomy, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205-2196, USA
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Kasturi KN, Hatakeyama A, Murai C, Gordon R, Phelps RG, Bona CA. B-cell deficiency does not abrogate development of cutaneous hyperplasia in mice inheriting the defective fibrillin-1 gene. J Autoimmun 1997; 10:505-17. [PMID: 9451590 DOI: 10.1006/jaut.1997.0158] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Tight-skin (TSK) mouse, the experimental model for scleroderma, develops cutaneous hyperplasia, cardiac hypertrophy, pulmonary emphysema and autoimmunity against scleroderma target autoantigens. The cutaneous hyperplasia is associated with the accumulation of microfibrils and elastic fibers in the middle and deep dermis. Fibrillin-1 (Fbn-1) is a major component of the 10-12 nm microfibrils found in the extracellular matrix. In this study we report the identification of a genetic marker in the Fbn-1 gene that can distinguish the mutant phenotype. TSK mice exhibit an unique polymorphism in the Fbn-1 gene. RNA analysis, PCR analysis and sequence determination of the mutant gene showed that the Fbn-1 gene polymorphism is due to intragenic duplication of a segment of the gene coding for 3.0 Kb of mRNA sequence (10 Kb of the genome). Histological analysis of skin samples from F1 progeny obtained by crossing TSK mice with JH-/-, RAG2-/- or vit/vit showed a significant correlation between the inheritance of the defective Fbn-1 gene and the development of cutaneous hyperplasia. Further, our results also show that in mice deficient in mature B cells inheriting the defective Fbn-1 gene, development of cutaneous hyperplasia is not abrogated. Thus, production of autoantibodies or the presence of mature B lymphocytes do not play an integral role in the pathogenesis of cutaneous hyperplasia.
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Affiliation(s)
- K N Kasturi
- Department of Microbiology, Mount Sinai School of Medicine, New York, NY 10029, USA
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Kasturi K, Muryoi T, Shibata S, Hatakeyama A, Murai C, Simakoshi Y, Bona C. Functional properties and molecular characteristics of autoantibodies associated with tight skin syndrome. Ann N Y Acad Sci 1997; 815:253-62. [PMID: 9186662 DOI: 10.1111/j.1749-6632.1997.tb52067.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- K Kasturi
- Department of Microbiology, Mount Sinai School of Medicine, New York, New York 10029, USA
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Frondoza C, Jones L, Rose NR, Hatakeyama A, Phelps R, Bona C. Development of scleroderma-like syndrome in Tsk/+ mice is not enhanced by silicone administration. Curr Top Microbiol Immunol 1996; 210:299-306. [PMID: 8565570 DOI: 10.1007/978-3-642-85226-8_31] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The possible role of silicone in the pathogenesis of a scleroderma-like syndrome is still unresolved. It has been proposed that silicone escaping from breast implants potentiates the progression of the disease. To clarify whether silicone enhances development of fibrotic skin lesions and autoantibodies, we tested its effect on tight skin (TSK/+) mice. TSK/+ mice spontaneously develop skin fibrosis and characteristic autoantibodies which resemble human scleroderma. The results of the present study indicate that silicone administration does not enhance development of skin fibrosis nor synthesis of autoantibodies to RNA polymerase and topoisomerase in TSK/+ mice.
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Affiliation(s)
- C Frondoza
- Johns Hopkins Dept. of Orthopaedic Surgery, USA
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Abstract
Scleroderma or systemic sclerosis (SSc) has been associated with certain class II antigens of the major histocompatibility complex (MHC), including HLA-DR1, DR2, DR3, DR5, and DR52. In general, these earlier HLA correlations were weak and varied considerably among reporting centers and different ethnic populations. More recently, a variety of disease-specific autoantibodies have been discovered including anti-centromere, antitopoisomerase I, and a variety of anti-nucleolar antibodies. These specificities show little overlap among one another, and each are markers for certain clinical features of SSc. At the same time, molecular studies of the MHC have provided more accurate methods for defining specific HLA alleles. Now it is becoming clear that certain HLA class II alleles, especially HLA-DQ, are more strongly associated with autoantibody subsets of SSc than with the disease itself. For example, anticentromere antibodies are strongly associated with HLA-DQB1*0501 (DQ5), DQB1*0301 (DQ7) and other DQB1 alleles possessing a glycine or tyrosine residue in position 26 of the outermost domain. Anti-topoisomerase I antibodies occur in SSc patients with HLA-DQB1*0301 (DQ7), DQB1*0302 (DQ8), DQB1*0601 (DQ6 in Japanese), and other DQB1 alleles possessing a tyrosine residue in position 30. HLA-DQ alleles associated with these autoantibodies tend to be in linkage disequilibrium with the HLA-DR specificities previously associated weakly with SSc itself. Rare multiplex families with SSc also show these same HLA haplotypes co-segregating with autoantibody profiles in affected members. Thus, it appears that MHC alleles play a role in affecting the serological expression of SSc, and the implications of these recent findings are discussed.
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Affiliation(s)
- F C Arnett
- Department of Internal Medicine, University of Texas-Houston Health Science Center 77030, USA
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Abstract
There is much evidence to suggest that scleroderma in human patients is caused by a fundamental defect in the immune system. In tightskin mice, the scleroderma syndrome is associated with autoimmunity, particularly autoantibodies interacting with scleroderma target antigens.
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Affiliation(s)
- C Bona
- Mount Sinai Medical Center, New York
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Kasturi KN, Yio XY, Bona CA. Molecular characterization of J558 genes encoding tight-skin mouse autoantibodies: identical heavy-chain variable genes code for antibodies with different specificities. Proc Natl Acad Sci U S A 1994; 91:8067-71. [PMID: 8058758 PMCID: PMC44546 DOI: 10.1073/pnas.91.17.8067] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Tight-skin mouse, a mutant strain with a single gene defect, develops cutaneous hyperplasia and specific autoantibodies, like humans affected by scleroderma. The autoantibodies produced in the tight-skin mouse are encoded primarily by heavy-chain variable (VH) genes from the J558 family. To understand the genetic basis of production of autoantibodies, we have analyzed the structure of J558 genes encoding these autoantibodies. The results showed that J558 genes encoding these antibodies were not derived from a selected germ-line gene(s) or a single subfamily but were derived from genes belonging to diverse J558 subfamilies. However, two prototype VH genes representing two new subfamilies were found to be repeatedly expressed in their germ-line form in eight independent clones. Autoantibodies with distinct specificities appear to be generated by pairing of similar/identical VH genes with different V kappa genes derived from the same or different families. Fourteen of 18 autoantibodies shared a conserved heptapeptide sequence motif, YNEKFKG, in the second complementarity-determining region of heavy chains. Usage of germ-line genes from diverse J558 subfamilies bearing a common motif to encode autoantibodies suggests a regulatory role for this motif. Thus, selection and expansion of the autoreactive B-cell repertoire in the tight-skin mouse appear to be VH-gene mediated. The frequency of N nucleotide addition at diversity-joining (D-JH) junctions was lower, whereas the frequency of usage of the DFL16 segment was higher. Finally, in contrast to normal and other autoimmune mouse strains, the frequencies of D-D fusions and D inversions were higher in tight-skin mouse total immunoglobulin as well as autoantibody repertoires.
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Affiliation(s)
- K N Kasturi
- Department of Microbiology, Mount Sinai School of Medicine, New York, NY 10029-6574
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Kasturi KN, Shibata S, Muryoi T, Bona CA. Tight-skin mouse an experimental model for scleroderma. Int Rev Immunol 1994; 11:253-71. [PMID: 7523551 DOI: 10.3109/08830189409061731] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- K N Kasturi
- Department of Microbiology, Mount Sinai School of Medicine, New York, NY 10029
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Kasturi KN, Daian C, Saitoh Y, Muryoi T, Bona CA. Tight-skin mouse autoantibody repertoire: analysis of VH and VK gene usage. Mol Immunol 1993; 30:969-78. [PMID: 7688852 DOI: 10.1016/0161-5890(93)90122-r] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
In the previous studies we have shown that tight-skin (TSK) mouse is an experimental model for systemic sclerosis. This mutant mouse develops autoantibodies specific for scleroderma target antigens. To determine whether the expansion of autoantibody repertoire in TSK mouse occurs by selective expansion of certain variable region gene families, and whether CD5+ B cells contribute significantly to the production of autoantibodies, we have analyzed a panel of 60 hybridomas producing autoantibodies specific for scleroderma target autoantigens. Northern analysis of RNAs from these hybridomas showed that 70% were expressing genes from VHJ558 family while genes from 36-09 and J606 families were not at all represented. In contrast, in the cDNA libraries derived from splenic B cells, the expression of VHJ558 and 36-09 gene families were at an expected frequency corresponding to their genomic complexity (44% and 11.6%, respectively). These results demonstrate that there is a strong bias toward the use of J558 genes in TSK mouse autoantibody repertoire. On the other hand the expression of VK gene families was mostly random and corresponded to their frequency in splenic C kappa cDNA library. The pairing of VH:VK genes was stochastic. Analysis of the expression of J segments, however, revealed that JH2 and JK2 were predominantly used in the autoantibodies. Analysis of the expression CD5 mRNA in these hybridomas indicate that CD5+ B cells do not contribute significantly to the autoimmunity in TSK mice. These findings suggest that the expansion of peripheral autoreactive B cells in TSK mouse is determined by their immunoglobulin variable region rather than the genetic properties linked to a particular B cell subset.
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Affiliation(s)
- K N Kasturi
- Department of Microbiology, Mount Sinai School of Medicine, New York, NY 10029
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