| 1. |
|
|
| 2. |
- Klareskog, Lars, et al.
(författare)
-
Genes, environment and immunity in the development of rheumatoid arthritis
- 2006
-
Ingår i: Current Opinion in Immunology. - : Elsevier BV. - 0952-7915 .- 1879-0372. ; 18:6, s. 650-655
-
Tidskriftsartikel (refereegranskat)abstract
- The combined role of genes, environment and immunity in the development of rheumatoid arthritis (RA) has been the subject of recent investigations. New data support a gene-environment interaction between smoking and the MHC class II HLA-DRB1 shared epitope (SE) genes in anti-citrulline antibody (anti-CP(+)) RA but not in anti-CP(-) disease. These data from genetic epidemiology, together with information on citrullination in the lungs of smokers, have prompted the formulation of a new etiological hypothesis for anti-CP(+) RA, suggesting that smoking in the context of HLA-DR SE might trigger immunity to citrulline-modified proteins and that this immunity, after several years, might cause arthritis.
|
|
| 3. |
- Klareskog, Lars, et al.
(författare)
-
Immunity to Citrullinated Proteins in Rheumatoid Arthritis
- 2008
-
Ingår i: Annual Review of Immunology. - : Annual Reviews. - 0732-0582 .- 1545-3278. ; 26, s. 651-675
-
Forskningsöversikt (refereegranskat)abstract
- Antibodies to citrullinated proteins (ACPA), i.e., to peptides posttranslationally modified by the conversion of arginine to citrulline, are specific serological markers for rheumatoid arthritis (RA). Studies on anticitrulline immunity, summarized in this review, demonstrate that the criterion-based syndrome RA should be subdivided into at least two distinct subsets (ACPA-positive and ACPA-negative disease). A new etiological model is proposed for ACPA-positive RA, built on MHC class II-dependent activation of adaptive immunity. Fundamentals of this model include the following: (a) ACPA antedate onset of arthritis; (b) ACPA may aggravate arthritis in rodents; (c) ACPA are triggered in the context of genes that confer susceptibility to RA (HLA-DRB1 SE) and by environmental agents triggering RA (smoking or bacterial stimuli); (d) ACPA may complex with citrullinated proteins present in target tissue as part of a multistep process for arthritis development. The model provides a new basis for molecular studies on the pathogenesis of ACPA-positive arthritis.
|
|
| 4. |
- Källberg, Henrik, et al.
(författare)
-
Gene-gene and gene-environment interactions involving HLA-DRB1, PTPN22, and smoking in two subsets of rheumatoid arthritis
- 2007
-
Ingår i: American Journal of Human Genetics. - : Elsevier BV. - 0002-9297 .- 1537-6605. ; 80:5, s. 867-875
-
Tidskriftsartikel (refereegranskat)abstract
- Gene-gene and gene-environment interactions are key features in the development of rheumatoid arthritis (RA) and other complex diseases. The aim of this study was to use and compare three different definitions of interaction between the two major genetic risk factors of RA—the HLA-DRB1 shared epitope (SE) alleles and the PTPN22 R620W allele—in three large case-control studies: the Swedish Epidemiological Investigation of Rheumatoid Arthritis (EIRA) study, the North American RA Consortium (NARAC) study, and the Dutch Leiden Early Arthritis Clinic study (in total, 1,977 cases and 2,405 controls). The EIRA study was also used to analyze interactions between smoking and the two genes. “Interaction” was defined either as a departure from additivity, as interaction in a multiplicative model, or in terms of linkage disequilibrium—for example, deviation from independence of penetrance of two unlinked loci. Consistent interaction, defined as departure from additivity, between HLA-DRB1 SE alleles and the A allele of PTPN22 R620W was seen in all three studies regarding anti-CCP–positive RA. Testing for multiplicative interactions demonstrated an interaction between the two genes only when the three studies were pooled. The linkage disequilibrium approach indicated a gene-gene interaction in EIRA and NARAC, as well as in the pooled analysis. No interaction was seen between smoking and PTPN22 R620W. A new pattern of interactions is described between the two major known genetic risk factors and the major environmental risk factor concerning the risk of developing anti-CCP–positive RA. The data extend the basis for a pathogenetic hypothesis for RA involving genetic and environmental factors. The study also raises and illustrates principal questions concerning ways to define interactions in complex diseases.
|
|
| 5. |
- Källberg, Henrik, et al.
(författare)
-
Smoking is a major preventable risk factor for rheumatoid arthritis : estimations of risks after various exposures to cigarette smoke
- 2011
-
Ingår i: Annals of the Rheumatic Diseases. - : BMJ. - 0003-4967 .- 1468-2060. ; 70:3, s. 508-511
-
Tidskriftsartikel (refereegranskat)abstract
- Background Earlier studies have demonstrated that smoking and genetic risk factors interact in providing an increased risk of rheumatoid arthritis (RA). Less is known on how smoking contributes to RA in the context of genetic variability, and what proportion of RA may be caused by smoking. Objectives To determine the association between the amount of smoking and risk of RA in the context of different HLA-DRB1 shared epitope (SE) alleles, and to estimate proportions of RA cases attributed to smoking. Design, Setting and Participants Data from the Swedish Epidemiological Investigation of Rheumatoid Arthritis (EIRA) case-control study encompassing 1204 cases and 871 controls were analysed. Main Outcome Measure Estimated OR to develop RA and excess fraction of cases attributable to smoking according to the amount of smoking and genotype. Results Smoking was estimated to be responsible for 35% of anticitrullinated protein/peptide antibody (ACPA)positive cases. For each HLA-DRB1 SE genotype, smoking was dose-dependently associated with an increased risk of ACPA-positive RA (p trend <0.001). In individuals carrying two copies of the HLA-DRB1 SE, 55% of ACPA-positive RA was attributable to smoking. Conclusions Smoking is a preventable risk factor for RA. The increased risk due to smoking is dependent on the amount of smoking and genotype.
|
|
| 6. |
- Laki, Judit, et al.
(författare)
-
Very high levels of anti-citrullinated protein antibodies are associated with HLA-DRB1*15 non-shared epitope allele in patients with rheumatoid arthritis
- 2012
-
Ingår i: Arthritis and Rheumatism. - : Wiley. - 0004-3591 .- 1529-0131. ; 64:7, s. 2078-2084
-
Tidskriftsartikel (refereegranskat)abstract
- Objective Production of anticitrullinated protein antibodies (ACPAs) is an important biomarker for rheumatoid arthritis (RA). We undertook this study to determine whether genetic factors (HLADRB1 alleles) are associated with extreme ACPA levels in individuals with ACPA-positive RA, and to ascertain whether there are any phenotypic characteristics associated with these subgroups of RA. Methods HLADRB1 allelic groups were genotyped in 1,073 ACPA-positive RA patients from the Swedish Epidemiological Investigation of Rheumatoid Arthritis study. We found that 283 patients (26.4%) had high ACPA levels (defined as >1,500 units/ml using the Euro-Diagnostica anti-CCP2 test), while the rest of the patients had moderate ACPA levels and served as the comparison group. A replication group consisted of 235 RA patients. Results No significant differences in baseline disease activity were observed between patients with high and those with moderate ACPA levels. However, the HLADRB1*15 allele was associated with high ACPA levels (P = 0.0002). A similar trend was detected in HLADRB1*15positive patients in the replication cohort, with meta-analysis of the discovery and replication cohorts demonstrating an overall effect of HLADRB1*15 on development of high ACPA levels in both the discovery and replication cohorts (P < 0.0001 by Mantel-Haenszel test with a fixed-effects model). Conclusion Our data indicate that HLADRB1*15 may promote the production of high ACPA levels. Due to the high value of ACPA level scores in the 2010 American College of Rheumatology/European League Against Rheumatism classification criteria for RA, the presence of HLADRB1*15 may, at least in part, contribute to fulfilling the criteria for RA. This illustrates the complex nature of the genetic regulation of ACPA levels. Additional mechanistic studies of the regulation of ACPAs and ACPA-positive RA are pending.
|
|
| 7. |
- Lundström, Emeli, et al.
(författare)
-
Opposing effects of HLA-DRB1*13 alleles on the risk of developing anti-citrullinated protein antibody-positive and anti-citrullinated protein antibody-negative rheumatoid arthritis
- 2009
-
Ingår i: Arthritis and Rheumatism. - : Wiley. - 0004-3591 .- 1529-0131. ; 60:4, s. 924-930
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: The effect of non-shared epitope HLA-DRB1 alleles on rheumatoid arthritis (RA) is poorly understood. This study was undertaken to investigate the effects of several HLA-DRB1 alleles, independent of the shared epitope, on the risk of developing anti-citrullinated protein antibody (ACPA)-positive or ACPA-negative RA in a large case-control study. METHODS: HLA typing for the DRB1 gene was performed in 1,352 patients with RA and 922 controls from the Swedish Epidemiological Investigation of Rheumatoid Arthritis study. Relative risks (RRs) and 95% confidence intervals (95% CIs) were calculated. RESULTS: DRB1*13 was found to protect against ACPA-positive RA when stratifying for the shared epitope and using a dominant genetic model (RR 0.41 [95% CI 0.26-0.64]). Furthermore, DRB1*13 neutralized the effect of the shared epitope in ACPA-positive RA (RR 3.91 [95% CI 3.04-5.02] in patients who had the shared epitope but not DRB1*13, and RR 1.22 [95% CI 0.81-1.83] in patients with both the shared epitope and DRB1*13, as compared with patients negative for both the shared epitope and DRB1*13). However, we did not replicate the previous published risk of ACPA-negative RA conferred by DRB1*03 when a dominant genetic model was used (RR 1.29 [95% CI 0.91-1.82]). Similarly, no significant effect of DRB1*03 on RR for ACPA-negative RA was seen using the recessive genetic model (RR 1.18 [95% CI 0.6-2.4]). In contrast, the combination of DRB1*03 and DRB1*13 was significantly associated with increased risk of developing ACPA-negative RA (RR 2.07 [95% CI 1.17-3.67]). CONCLUSION: Our findings indicate that the DRB1*13 allele plays a dual role in the development of RA, by protecting against ACPA-positive RA but, in combination with DRB1*03, increasing the risk of ACPA-negative RA
|
|
| 8. |
- Manivel, Vivek Anand, et al.
(författare)
-
Anticollagen type II antibodies are associated with an acute onset rheumatoid arthritis phenotype and prognosticate lower degree of inflammation during 5 years follow-up
- 2017
-
Ingår i: Annals of the Rheumatic Diseases. - : BMJ. - 0003-4967 .- 1468-2060. ; 76:9, s. 1529-1536
-
Tidskriftsartikel (refereegranskat)abstract
- ObjectiveAntifibrillar collagen type II (anti-CII) antibody-positive patients with rheumatoid arthritis (RA) have early but not late signs of increased inflammation and joint erosions. We wanted to replicate this in a large RA cohort, and to relate to human leukocyte antigen (HLA)-DRB1* alleles.MethodsAnti-CII and anti-cyclic citrullinated peptide (CCP)2 were measured at baseline in 773 patients with RA from the Swedish Epidemiological Investigation in Rheumatoid Arthritis (EIRA) study with clinical follow-up data from the Swedish Rheumatology Quality Register (SRQ) registry, and 1476 with HLA-DRB1* information. Comparisons were done concerning C reactive protein (CRP), erythrocyte sedimentation rate (ESR), tender joint count (TJC), swollen joint count (SJC), Disease Activity Score encompassing 28 joints based on ESR (DAS28), DAS28CRP, pain-Visual Analogue Scale (VAS), global-VAS and Health Assessment Questionnaire Score (HAQ) at eight occasions during 5 years, and association with HLA-DRB1* alleles.ResultsAnti-CII associated with elevated CRP, ESR, SJC, DAS28 and DAS28CRP at diagnosis and up to 6 months, whereas anti-CCP2 associated with SJC and DAS28 from 6 months to 5 years, but not earlier. The anti-CII-associated phenotype was strong, and predominated in anti-CII/anti-CCP2 double-positive patients. Anti-CII was associated with improvements in CRP, ESR, SJC, TJC and DAS28, whereas anti-CCP2 was associated with deteriorations in SJC and DAS28 over time. Anti-CII-positive patients achieved European League Against Rheumatism good or moderate response more often than negative patients. Anti-CII was positively associated with HLA-DRB1*01 and HLA-DRB1*03, with significant interaction, and double-positive individuals had >14 times higher mean anti-CII levels than HLA double negatives. Whereas smoking was associated with elevated anti-CCP2 levels, smokers had lower anti-CII levels.ConclusionsAnti-CII seropositive RA represents a distinct phenotype, in many respects representing the converse to the clinical, genetic and smoking associations described for anticitrullinated protein peptide autoantibodies. Although not diagnostically useful, early anti-CII determinations predict favourable inflammatory outcome in RA.
|
|
| 9. |
- Padyukov, Leonid, et al.
(författare)
-
A genome-wide association study suggests contrasting associations in ACPA-positive versus ACPA-negative rheumatoid arthritis
- 2011
-
Ingår i: Annals of the Rheumatic Diseases. - : BMJ. - 0003-4967 .- 1468-2060. ; 70:2, s. 259-265
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Rheumatoid arthritis (RA) can be divided into two major subsets based on the presence or absence of antibodies to citrullinated peptide antigens (ACPA). Until now, data from genome-wide association studies (GWAS) have only been published from ACPA-positive subsets of RA or from studies that have not separated the two subsets. The aim of the current study is to provide and compare GWAS data for both subsets. Methods and results GWAS using the Illumina 300K chip was performed for 774 ACPA-negative patients with RA, 1147 ACPA-positive patients with RA and 1079 controls from the Swedish population-based case-control study EIRA. Imputation was performed which allowed comparisons using 1 723 056 single nucleotide polymorphisms (SNPs). No SNP achieved genome-wide significance (2.9 x 10(-8)) in the comparison between ACPA-negative RA and controls. A case-case association study was then performed between ACPA-negative and ACPA-positive RA groups. The major difference in this analysis was in the HLA region where 768 HLA SNPs passed the threshold for genome-wide significance whereas additional contrasting SNPs did not reach genome-wide significance. However, one SNP close to the RPS12P4 locus in chromosome 2 reached a p value of 2 x 10(6) and this locus can thus be considered as a tentative candidate locus for ACPA-negative RA. Conclusions ACPA-positive and ACPA-negative RA display significant risk allele frequency differences which are mainly confined to the HLA region. The data provide further support for distinct genetic aetiologies of RA subsets and emphasise the need to consider them separately in genetic as well as functional studies of this disease.
|
|
| 10. |
- Phuong, Thuy Nguyen Thi, et al.
(författare)
-
Clinical characteristics of Vietnamese patients with idiopathic inflammatory myopathies and autoantibodies to aminoacyl-transfer RNA synthetases
- 2021
-
Ingår i: International Journal of Rheumatic Diseases. - : John Wiley & Sons. - 1756-1841 .- 1756-185X. ; 24:5, s. 663-670
-
Tidskriftsartikel (refereegranskat)abstract
- Objective To assess clinical phenotypes of anti-aminoacyl-transfer RNA synthetases (aaRS) autoantibodies in Vietnamese patients of Kinh ethnicity with idiopathic inflammatory myopathies (IIM). Methods In a cross-sectional study 23 patients with anti-aaRS autoantibodies were compared to 36 patients with other myositis-specific antibodies and to 69 seronegative patients with IIM. Assessments included muscle performance, extra-muscular involvement, and disease activity according to the International Myositis Assessment and Clinical Studies (IMACS). Sera were tested by a line immunoassay (Euroline Myositis Profile 4). Results The frequency of anti-Jo-1 antibodies was 56.5%, anti-EJ antibodies 26.1%, and anti-PL-7 antibodies 17.4%, while anti-PL-12 and anti-OJ antibodies were not present in any case. All patients with anti-aaRS autoantibodies had signs of myositis. At time of investigation 22/23 patients had muscle weakness, 52.2% arthritis, 34.8% Raynaud's phenomenon, 73.9% fever, 14.3% mechanic's hands and 56.5% dysphagia. Interstitial lung disease was present in 52.2%, and pulmonary hypertension in 56.5%. The anti-aaRS autoantibody positive group had higher disease activity in the domains of skin and pulmonary disease compared to the seronegative group and had lower disease activity in skeletal disease compared to the anti-melanoma differentiation-associated protein 5-positive patients. The clinical presentation of antisynthetase syndrome was similar between the aaRS autoantibody specificities with the exception of more frequent pulmonary hypertension in anti-Jo-1 positive patients. Conclusions Different aaRS autoantibody specificities may vary between different ethnic populations for reasons that still need to be clarified. Furthermore, the high frequency of pulmonary hypertension is noteworthy but otherwise clinical manifestations associated with aaRS autoantibodies did not differ from other ethnic populations.
|
|
