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E Toussirot

Publications and source records attributed to E Toussirot.

At least 19 recordsLinked to original sources
PubMed2006

[The immunogenetics of ankylosing spondylitis].

BACKGROUND: Ankylosing spondylitis (AS) is an inflammatory rheumatic disease with axial involvement but its physiopathology remains unexplained. This latter combines genetic and environmental factors as well as an abnormal immune response. CURRENT TOPICS AND IMPORTANT RESULT: This review addresses the different aspects of AS immunogenetic. A genetic background in AS is suggested by familial cases, concordance rate in twins and transmission of the disease in siblings. Ankylosing spondylitis is strongly associated with the expression of the HLA Class I antigen, B27, but also with other genes not yet identified since currently, only chromosomic area have been linked to AS. Studies of candidate genes or genome screening allow to determine these chromosomic regions. HLA-B27 is directly associated with the disease physiopathology as suggested by animal models of rats transgenic for human HLA-B27 and beta2 microglobulin. This HLA molecule have original biological properties, in particular a slow heavy chain folding and the formation of heavy chain homodimers without light chain. However, HLA B27 is a functional molecule and assumes its property of presenting peptide of 9 amino acids to CD8+ T cells. Interaction modelling studies between HLA B27 and peptides have identified peptide and peptide groove amino acid sequences, with the identification of critical positions on the HLA B27 molecule for the peptide interaction. Original biochemical properties of HLA-B27 include diminished bacterial antigen response and CD4+ T lymphocyte stimulation. Innate immunity is also of interest in AS, as suggested by the presence of macrophage and polymorphonuclear neutrophils in AS synovitis, as well as the contribution of Toll-like receptors. FUTURE PROSPECTS AND PROJECTS: Thus in AS, the inflammatory process and then the clinical consequences may be explained by the involvement of HLA-B27, a bacterial antigen presentation, an abnormal immune response and the contribution of innate immunity, T CD4+ but also T CD8+ cells. The original molecular structures of HLA-B27 are certainly involved in this complex physiopathology, but their direct influence on the disease remains to be precised.

Animals↗
PubMed2004

Relationship between growth hormone-IGF-I-IGFBP-3 axis and serum leptin levels with bone mass and body composition in patients with rheumatoid arthritis.

OBJECTIVES: Hormonal factors playing a role in bone mass and body composition have been rarely assessed in rheumatoid arthritis (RA). In this study, we aimed to evaluate the growth hormone (GH)-insulin-like growth factor-I (IGF-I)-insulin-like growth factor binding protein-3 (IGFPB-3) axis and serum leptin levels in patients with RA and to determine whether these hormonal/growth factors may influence bone mass and body composition in RA. METHODS: Serum GH, IGF-I, IGFPB-3 and leptin were evaluated in 38 corticosteroid-treated RA patients, 14 non-RA patients under corticosteroids (corticosteroid controls, CC) and 32 healthy controls (HC). Bone density was evaluated using dual X-ray absorptiometry (DEXA), and expressed as bone mineral density (BMD), and quantitative ultrasound (QUS). Body composition was assessed by DEXA. RESULTS: The three groups differed regarding femoral neck, total body BMD, lean mass and QUS parameters with lower values in the RA group (all P < or = 0.05). Growth hormone was higher in RA patients (P=0.0001) while IGF-I and IGFBP-3 did not differ between the three groups. In RA patients there was a tendency to high serum leptin levels and leptin strongly correlated with fat mass (r=0.83, P<0.0001), but not with bone mass measurements or inflammatory parameters. There were no differences for lean mass, GH and leptin between CC and HC. CONCLUSION: Our results suggest that these GH and leptin modifications could have an influence on both bone mass and body composition in RA.

Absorptiometry, Photon↗
PubMed2003

High serum vascular endothelial growth factor correlates with disease activity of spondylarthropathies.

Angiogenesis is involved in chronic inflammatory joint diseases such as rheumatoid arthritis (RA). Vascular endothelial growth factor (VEGF) plays a crucial role in angiogenesis. The spondylarthropathies (SpA) are characterized by enthesitis and synovitis, in which blood vessels participate. The objective of this study was to investigate serum VEGF levels and their potential associations with disease activity markers for SpA. Sera were collected from 105 patients with SpA (72 with ankylosing spondylitis (AS), four with psoriatic arthritis (PsA), six with reactive arthritis (ReA), eight with enteropathic arthropathy and 15 with undifferentiated SpA), 50 patients with rheumatoid arthritis (RA) and 64 healthy controls. Disease activity in SpA patients was assessed using the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and laboratory parameters of inflammation [erythrocyte sedimentation rate (ESR) and C-reactive protein level (CRP)]. Serum VEGF levels were significantly higher in SpA patients (316.4 +/- 215.6 pg/ml) and RA patients (405.2 +/- 366.5) than in controls (217.3 +/- 145.2) (P = 0.003). In SpA patients, serum VEGF levels correlated with disease activity indices (BASDAI: r = 0.22, P = 0.04; ESR: r = 0.3, P = 0.003; and CRP: r = 0.23, P = 0.02). Serum VEGF levels were not associated with presence of extra-articular manifestations or syndesmophytes or with the grade of sacroiliitis. These results suggest that VEGF and therefore angiogenesis may play a role in SpA pathogenesis and may serve as a disease activity marker in SpAs.

Adult↗
PubMed2002

TAP1 and TAP2 gene polymorphism in rheumatoid arthritis in a population in eastern France.

The 'transporter associated with antigen processing' (TAP) gene products are involved in the processing of endogenous peptides that bind to class I molecules. Polymorphism within these genes could alter the level of the immune response, a phenomenon relevant to the development of autoimmune diseases. In this study, we examined the polymorphism of TAP1 and TAP2 genes in patients with rheumatoid arthritis (RA). TAP1 and TAP2 typing was performed for 138 Caucasian RA patients and 100 healthy controls, all originating from eastern France. TAP1 polymorphic residues at positions 333 and 637 and amino acid variants 379, 565, 651 and 665 in the TAP2 gene were found using amplification refractory mutation system-polymerase chain reaction (ARMS-PCR). This method enabled us to determine four TAP1 alleles (TAP1A to TAP1D) and eight TAP2 alleles (TAP2A to TAP2H). All patients and controls had been HLA-DRB1* genotyped. The polymorphic residues TAP1333 and TAP1637 did not show any difference in their distribution between patients and controls. Similar findings were obtained for TAP2379 and TAP2665. However, we found an increased frequency of Thr homozygosity and heterozygosity at position 565 in the TAP2 gene in RA patients (RA vs. controls: 25.3 vs. 14%; P = 0.032; OR = 2.09; CI = 1.01-4.38). Similarly, the prevalence of subjects who were homozygote and heterozygote for Cys651 was increased in the RA group (RA vs. controls: 36.8 vs. 11%; P = 0.02). The dimorphic site TAP2565 defines TAP2D and TAP2E alleles, while the site at position 651 characterizes TAP2F. Thus, we found that TAP2D and TAP2E alleles were more prevalent in RA, but not significantly so (RA vs. controls: TAP2D: 10 vs. 3.6%; P = 0.24; TAP2E: 3.6 vs. 0%; P = 0.19). Similarly, the frequency of TAP2F was higher in RA patients (24.5%) than in controls (11.3%), but this was not significant after correction (P = 0.029; Pcorr = 0.17). Finally, we found no linkage disequilibrium between DRB1* RA-associated alleles and amino acid substitution Thr565 or TAP2D and TAP2E alleles, whereas Cys651 (and TAP2F) was not independent of DRB1*04, a strongly RA-associated allele. Finally, Thr at position 565 in the TAP2 gene was associated with manifestations of disease severity in only a few patients. Examination of TAP1 and TAP2 gene polymorphisms in RA patients revealed an association between a particular amino acid residue, namely Thr565 in the TAP2 gene, and RA. This association was found to be weak and did not seem to be a predictor for the severity of the disease.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2001

Influence of shared epitope-negative HLA-DRB1 alleles on genetic susceptibility to rheumatoid arthritis.

OBJECTIVE: Most patients with rheumatoid arthritis (RA) express the shared epitope (SE). It is not known whether SE-negative HLA-DRB1 alleles influence the development of RA. This study examined the influence of SE-negative HLA-DR alleles (DRB1*X) on the development of RA in 3 different French populations. METHODS: HLA-DRB1 alleles were defined by polymerase chain reaction with sequence-specific oligonucleotide hybridization or sequence-specific primers. SE-negative alleles were classified according to the electric charge of their P4 pocket. HLA-DRB1 alleles *0103, *0402, *07, *08, *11 (except *1107), *12, and *13 have a neutral or negative P4 charge and are called DRB1*XP4n. HLA-DRB1*03, *0403, *0406, *0407, *0901, *1107, *14, *15, and *16 have a positive P4 charge and are called DRB1*XP4p. RESULTS: Among the SE-negative subjects, DRB1 genotypes with 1 or 2 DRB1*XP4n alleles were significantly overrepresented in the control subjects compared with the RA patients, whereas DRB1*XP4p/XP4p genotypes were equally represented in the patients and controls. In single-dose SE-positive subjects, SE/XP4n genotypes were equally represented in the patients and controls. However, SE/XP4p genotypes were significantly overrepresented in the RA patients. CONCLUSION: The DRB1*X allele polymorphism influences susceptibility to RA. Alleles that have a neutral or negative electric charge in their P4 pocket (DRB1*XP4n), such as DRB1*0103, *0402, *07, *08, *11 (except *1107), *12, and *13, protect against RA. Alleles that have a positive electric charge in their P4 pocket (DRB1*XP4p), such as DRB1*03, *0403, *0406, *0407, *0901, *1107, *14, *15, and *16, have no influence on the predisposition to RA.

Alleles↗
PubMed2001

Fibromyalgia developed after administration of gonadotrophin-releasing hormone analogue.

We report the case of a woman treated with a gonadotrophin-releasing hormone analogue for endometriosis who developed typical clinical features of fibromyalgia, with widespread musculoskeletal pain, sleep difficulties, neuropsychological complaints and tender points on clininal examination. The gonadotrophin-releasing hormone analogue treatment probably induced disturbances in the neuroendocrine system and the secretion of neurotransmitters, and may be suspected to be the cause of this case of fibromyalgia.

Adult↗
PubMed2001

Adult hypophosphatasia. Current aspects.

Hypophosphatasia is an inborn metabolic disorder in which abnormally low levels of the enzyme nonspecific alkaline phosphatase result in defective skeletal and dental mineralization (rickets, fractures, dental abnormalities) and in accumulation of the enzyme substrates (phosphoethanolamine, pyridoxal-5'phosphate and inorganic pyrophosphate). The build-up of inorganic pyrophosphate promotes the development of articular chondrocalcinosis. There are several forms of hypophosphatasia, with wide variations in severity. We report the case of a 53-year-old man with typical manifestations of moderate adulthood hypophosphatasia. Investigations in his family found the disease in a sister and two children. He had two autosomal mutations, which were transmitted recessively. Several mutations of the alkaline phosphatase gene have been identified. The genotype is correlated with the phenotype: some mutations are associated with milder forms and others with more severe forms of the disease.

Age of Onset↗
PubMed2001

Bone density, ultrasound measurements and body composition in early ankylosing spondylitis.

OBJECTIVES: In this cross-sectional study, we evaluated bone density using both dual-energy X-ray absorptiometry (DEXA) and quantitative ultrasound (QUS) techniques and examined the changes in body composition in patients with ankylosing spondylitis (AS). METHODS: Seventy-one patients were compared with seventy-one sex- and age-matched controls. Bone mineral density (BMD) was evaluated at the lumbar spine and femoral neck with a Lunar device. Total body measurements were also performed, giving BMD and bone mineral content (BMC) of the whole body, and fat and lean masses. Broadband ultrasound attenuation (BUA), speed of sound and stiffness were measured at the calcaneus using an Achilles ultrasound device. RESULTS: The patients had significantly lower lumbar spine, femoral neck and total body BMD as compared with controls (all P < 0.05). Total body BMC was also decreased in AS (P = 0.002). On the contrary, fat and lean masses did not differ between patients and controls as observed for QUS values. Mild to good correlations were found between BMD and QUS parameters (r ranging from 0.22 to 0.53; all P < or = 0.01). When applying the World Health Organization (WHO) definition for osteoporosis, we found that 46.5% of patients had lumbar spine osteopenia and/or osteoporosis, while 26.8% had femoral neck osteopenia and/or osteoporosis (controls: 23.9 and 10%; P = 0.001 and 0.08, respectively). No relationships between disease activity (as evaluated by erythrocyte sedimentation rate, serum C-reactive protein levels and BASDAI, a clinical index of disease activity) and BMD measurements were found and only femoral neck BMD correlated with disease duration (r = -0.25; P = 0.04). Finally, the presence of talalgia in AS did not influence the QUS values. CONCLUSION: These results confirm that AS patients have decreased BMD values at both the spine and femur, and also in total body measurements, reflecting a generalized bone loss. On the contrary, soft tissue composition does not seem to be influenced by the disease. QUS parameters were found to be similar between patients and controls, suggesting that the QUS method did not provide additive information to DEXA. As it is thought that QUS provides information about qualitative properties of bone, the normal results of QUS values in our patient series argue against modifications in AS bone micro-architecture.

Absorptiometry, Photon↗
PubMed2001

Therapeutic advances in ankylosing spondylitis.

Ankylosing spondylitis (AS) is a systemic inflammatory rheumatic disease involving spinal and sacroiliac joints. This condition is responsible for back pain, stiffness, but also loss of functional capacity with socio-economic consequences. The management of AS includes patient education, rest, a programme of regular physical exercise, together with the use of NSAIDs. Second-line treatments are required in cases of severe or refractory AS, however only sulfasalazine has proven to benefit AS patients with peripheral arthritis. In spite of this management, the disease may not be adequately controlled, mainly for patients with refractory axial disease, enthesopathy or extra-articular features. Thus, new innovative treatments are needed for AS. It is likely that the new NSAIDs or COX-2 specific inhibitors will certainly take the place of the conventional NSAIDs, with regard to their superior tolerability. Methotrexate is a therapeutic option for AS treatment, but its usefulness in this disease remains to be established in adequate controlled studies. Finally, the TNF-alpha targeting drugs, namely thalidomide and the anti-TNF-alpha mAb, infliximab, have given promising results in the treatment of severe and/or refractory AS patients, however further controlled studies are required. In addition, the long-term use (efficacy and tolerability) of these two agents deserves attention.

Cyclooxygenase Inhibitors↗
PubMed2000

The association of HLA-DM genes with rheumatoid arthritis in Eastern France.

In this study, the polymorphisms of the HLA DMA and DMB genes in patients with rheumatoid arthritis (RA) were examined.DMA and DMB typing was performed in 120 white RA patients from eastern France and 100 healthy controls, using PCR-SSO (sequence specific oligonucleotide probes) method for DMA determination and PCR-RFLP (restriction fragment length polymorphism) method for DMB typing. All patients and controls had been HLA DRB1* genotyped.DMA*0103 was found significantly increased in RA patients (RA vs. controls: 18.3% vs. 4%) (p(corr) = 0.004; OR: 5.39; CI: 1.67-19.23). A decreased frequency of DMA*0102 was also observed in the RA group (RA vs. controls: 18.3% vs. 31%), but not significantly. There were no differences in the prevalence of DMB alleles between RA and controls. The patients and the controls were then stratified according to the expression of the HLA DRB1* RA-linked alleles (DRB1*01 and *04) and this allowed us to find no linkage disequilibrium between DMA*0103 and DRB1*01 or *04 alleles. Finally, most DMA*0103 patients were positive for rheumatoid factors and had extraarticular involvement such as subcutaneous nodules. Thus, our results suggest that DMA*0103 could be an additional genetic factor for RA susceptibility in French whites.

Adolescent↗
PubMed2000

[Infectious osteoarthritis due to Propionibacterium acnes. Two new cases].

INTRODUCTION: Propionibacterium acnes is an anaerobic germ, usually found as a saprophyte of the skin and the mucosa. It may be responsible for iatrogenic or spontaneous osteoarhritis. EXEGESIS: We report two new cases of septic arthritis induced by P. acnes: a case of iatrogenic spondylodiscitis and a case of spontaneous septic arthritis of the lumbar facet joints. The two patients were immunocompetent, without acne. CONCLUSION: Except for patients with criteria of the SAPHO syndrome (synovitis-acne-pustulosis-hyperostosis-osteomyelitis), osteoarthritis caused by P. acnes is increasingly described. The number of these infections is probably underestimated because of the technical problems involved in isolating P. acnes in the laboratory.

Acquired Hyperostosis Syndrome↗