Ágnes Gyetvai

Anti-citrullinated protein/peptide autoantibodies in association with genetic and environmental factors as indicators of disease outcome in rheumatoid arthritis.

Anti-citrullinated protein/peptide antibodies (ACPA) have recently emerged as sensitive and specific serological markers of rheumatoid arthritis (RA), providing superior alternative of the rheumatoid factor (RF) test in the laboratory diagnostics of RA. Citrullination is a post-translational modification of arginine by deimination, physiologically occurring during apoptosis, inflammation or keratinization. The presence of several citrullinated proteins has been demonstrated in the RA synovium. The identification of citrullinated epitopes as targets led to the development of the first and later second-generation anti-cyclic citrullinated peptide (anti-CCP) antibody assays. The anti-Sa antibody has been identified a decade ago; however, recent studies confirmed that anti-Sa is directed against citrullinated vimentin. The determination of ACPA may have important prognostic significance, since ACPA production can precede the onset of clinical RA symptoms by years. ACPA(+) individuals with early, undifferentiated arthritis may have higher risk to develop RA. ACPA has important prognostic role during the progression of RA and it has also been associated with pronounced radiographic progression. ACPA production has been associated with several genetic predisposing factors, including HLA-DRB1 and PTPN22 1858T alleles, as well as with environmental and lifestyle-related factors, primarily smoking and possibly, the use of oral contraceptives and excessive caffeine intake. Thus, the assessment of ACPA, in addition to clinical, radiographic and genetic outcome measures may be important to assess disease prognosis and aids to design effective, early therapeutic strategies.

Functional variants of interleukin-23 receptor gene confer risk for rheumatoid arthritis but not for systemic sclerosis

Objectives: Recently, an association was found between Crohn’s disease and the interleukin-23 receptor (IL-23R) gene. Since the IL-23/IL-17 pathway is known to associate with other autoimmune diseases, including rheumatoid arthritis (RA) and systemic sclerosis (SSc), we hypothesised that IL-23R could be a shared susceptibility gene. Methods: Groups of patients with rheumatoid arthritis (n = 412), systemic sclerosis (n = 224), Crohn’s disease (n = 190) and healthy controls (n = 220) were genotyped for rs10889677 (exon-3’UTR C2370A), rs2201841, and rs1884444 variants; the first two have been shown to confer risk for Crohn’s disease. Results: We observed an increased prevalence of the homozygous rs10889677 AA and homozygous rs2201841 CC genotypes both in the Crohn’s disease and in the RA groups as compared to the controls (12.1%, 11.9% vs 5.91%, p<0.05; and 13.2%, 13.1% vs 5.91%, p<0.05), but not in the SSc patients. Logistic regression analysis revealed that bearing these alleles represent risk for the development of rheumatoid arthritis (χ2 = 5.58, p = 0.018, OR = 2.15, 95% CI 1.14–4.06 for rs10889677; and χ2 = 7.45, p = 0.006, OR = 2.40, 95% CI 1.28–4.51 for rs2201841). The rs1884444 allele, which has been previously reported as neutral for development of Crohn’s disease, was also found neutral for all studied groups in the present study. Conclusions: The data reported here provide direct evidence that some allelic variants or haplogroups of IL-23R represent independent risk factors for rheumatoid arthritis as well as Crohn’s disease, but not for scleroderma.

Interaction of HLA-DRB1*03 and smoking for the development of anti-Jo-1 antibodies in adult idiopathic inflammatory myopathies: a European-wide case study

Objectives HLA-DRB1*03 is strongly associated with anti-Jo-1-positive idiopathic inflammatory myopathies (IIM) and there is now increasing evidence that Jo-1 antigen is preferentially expressed in lung tissue. This study examined whether smoking was associated with the development of anti-Jo-1 antibodies in HLA-DRB1*03-positive IIM. Methods IIM cases were selected with concurrent information regarding HLA-DRB1 status, smoking history and anti-Jo-1 antibody status. DNA was genotyped at DRB1 using a commercial sequence-specific oligonucleotide kit. Anti-Jo-1 antibody status was established using a line blot assay or immunoprecipitation. Results 557 Caucasian IIM patients were recruited from Hungary (181), UK (99), Sweden (94) and Czech Republic (183). Smoking frequency was increased in anti-Jo-1-positive IIM cases, and reached statistical significance in Hungarian IIM (45% Jo-1-positive vs 17% Jo-1-negative, OR 3.94, 95% CI 1.53 to 9.89, p<0.0001). A strong association between HLA-DRB1*03 and anti-Jo-1 status was observed across all four cohorts (DRB1*03 frequency: 74% Jo-1-positive vs 35% Jo-1-negative, OR 5.55, 95% CI 3.42 to 9.14, p<0.0001). The frequency of HLA-DRB1*03 was increased in smokers. The frequency of anti-Jo-1 was increased in DRB1*03-positive smokers vs DRB1*03-negative non-smokers (42% vs 8%, OR 7.75, 95% CI 4.21 to 14.28, p<0.0001) and DRB1*03-positive non-smokers (42% vs 31%, p=0.08). In DRB1*03-negative patients, anti-Jo-1 status between smokers and non-smokers was not significantly different. No significant interaction was noted between smoking and DRB1*03 status using anti-Jo-1 as the outcome measure. Conclusion Smoking appears to be associated with an increased risk of possession of anti-Jo-1 in HLA-DRB1*03-positive IIM cases. The authors hypothesise that an interaction between HLA-DRB1*03 and smoking may prime the development of anti-Jo-1 antibodies.

New classification of the shared epitope in rheumatoid arthritis: impact on the production of various anti-citrullinated protein antibodies

OBJECTIVE HLA-DR [shared epitope (SE)] alleles have recently been re-classified into S1, S2, S3P and S3D groups. S2 and S3P have been associated with increased risk for RA. We assessed the impact of S1, S2, S3P and S3D alleles on anti-citrullinated protein antibody (ACPA) production. Instead of comparing allele-carriers to non-carriers, we studied each allele group individually, using the X/X (non-SE) genotype as reference. METHODS Serum and genomic DNA samples of 91 RA patients and 78 healthy controls were obtained. Various ACPAs and IgM RF were determined by ELISA. HLA-DRB1 genotyping and subtyping was performed by PCR. HLA-DRB1 alleles were re-classified as described above. Correlations between SE and ACPAs were determined. RESULTS Not only S2 and S3P, but, to a lesser extent, S1 and S3D alleles also predisposed to anti-cyclic citrullinated peptide (CCP) production (P < 0.0001, P = 0.004, P = 0.01 and P = 0.027, respectively), with the following hierarchy of association: S2+S3P > S1+S3D > X/X. Similar associations were observed for anti-citrullinated vimentin. Anti-citrullinated fibrinogen (CF) exerted a different association pattern with the strongest correlation with S1 alleles [odds ratio (OR) 16.00; P = 0.05]. In addition, HLA-DRB1*15 alleles may represent a special predisposing effect for anti-CF antibody production. Finally, in this study, RF production was associated only with the HLA-DRB1*0401 SE allele (P = 0.04). CONCLUSIONS Our approach of comparing individual S allele carriers with X/X genotype patients allowed us to perform unequivocal analyses and demonstrate new associations. Thus, novel subgroups of RA could be identified with potential relevance for prognosis and therapy.

Associations of HLA-shared epitope, anti-citrullinated peptide antibodies and lifestyle-related factors in Hungarian patients with rheumatoid arthritis: data from the first Central-Eastern European cohort.

Joint Bone Spine - In Press.Proof corrected by the author Available online since mardi 5 juillet 2011

Human leukocyte antigen-DRB1 and -DQB1 genotyping in lupus patients with and without antiphospholipid syndrome.

We investigated the genetic background regarding major histocompatibility complex (MHC) II alleles in patients with systemic lupus erythematosus (SLE) only, in patients with SLE with secondary antiphospholipid syndrome (SLE+SAPS), and in patients whose clinical course began as primary antiphospholipid syndrome (PAPS) and subsequently progressed to SLE (PAPS+SLE) in order to explain the phenotypical differences found in our previous study. Those with primary or secondary APS present more thrombotic and less inflammatory activity. Fetal wastage was the highest in the PAPS+SLE group. We performed human leukocyte antigen (HLA)‐DRB1 and HLA‐DQB1 genotyping in 63 patients (26, 22, and 15 in SLE only, SLE+SAPS, and PAPS+SLE groups, respectively) and in 57 healthy controls, using PCR with sequence‐specific primers. We found that, as reported in the literature, the occurrence of DRB1*03 and DQB1*0201 alleles was higher in SLE patients than in controls, but these alleles were rare in the PAPS+SLE group (13% in PAPS+SLE vs. 46% in the SLE only group; P= 0.044). HLA‐DRB1*04 alleles were expressed frequently in both primary and secondary APS. DRB1*13, DQB1*06, and DQB1*0302 alleles were present more frequently in the PAPS+SLE patients than in the other groups, while the DQB1*0301 allele was rare. In this study we have shown that the SLE‐associated DRB1*03/DQB1*02 alleles occurred frequently in our lupus patients as well as in SLE patients with secondary APS. In patients who started as PAPS and later progressed to SLE, the allele frequency was fundamentally different. Taken together, our results confirmed that the HLA‐DRB1 and HLA‐DQB1 profile of PAPS and SAPS is different. Therefore it is unlikely that these alleles are responsible for the partly similar phenotype of the two groups.

Different Effects of Bortezomib on the Expressions of Various Protein Kinase C Isoenzymes in T Cells of Patients with Systemic Lupus Erythematosus and in Jurkat Cells

The effects of proteosome inhibitor Bortezomib (BZ) were studied in vitro for 24 h on the protein kinase C (PKC) profiles, rates of proliferation and apoptosis in Jurkat cells and lymphocytes of 10 patients with systemic lupus erythematosus (SLE) and nine healthy subjects. The expressions of PKC proteins, the rates of proliferation and apoptosis were determined. The effects of BZ were different in the Jurkat and lupus T cells. Whereas BZ elevated the expression of PKC θ, δ and ξ isoenzymes in the Jurkat cells, it was unable to do that in the lupus T cells. BZ induced a dose‐dependent increase in the apoptosis of Jurkat cells, while decreased the proliferation. The same effect of BZ was observed on the apoptosis of lymphocytes both in SLE and healthy subjects at concentrations higher than the therapeutic dose. We conclude that BZ treatment in vitro was not able to restore the SLE‐specific defect (decrease) in the expression of PKC isoenzymes in the T cells as it was expected. This can be a limiting factor in the positive clinical effects of BZ in lupus.

Hydrogen Sulfide Abrogates Hemoglobin-Lipid Interaction in Atherosclerotic Lesion

The infiltration of red blood cells into atheromatous plaques is implicated in atherogenesis. Inside the lesion, hemoglobin (Hb) is oxidized to ferri- and ferrylHb which exhibit prooxidant and proinflammatory activities. Cystathione gamma-lyase- (CSE-) derived H2S has been suggested to possess various antiatherogenic actions. Expression of CSE was upregulated predominantly in macrophages, foam cells, and myofibroblasts of human atherosclerotic lesions derived from carotid artery specimens of patients. A similar pattern was observed in aortic lesions of apolipoprotein E-deficient mice on high-fat diet. We identified several triggers for inducing CSE expression in macrophages and vascular smooth muscle cells including heme, ferrylHb, plaque lipids, oxidized low-density lipoprotein, tumor necrosis factor-α, and interleukin-1β. In the interplay between hemoglobin and atheroma lipids, H2S significantly mitigated oxidation of Hb preventing the formation of ferrylHb derivatives, therefore providing a novel function as a heme-redox-intermediate-scavenging antioxidant. By inhibiting Hb-lipid interactions, sulfide lowered oxidized Hb-mediated induction of adhesion molecules in endothelium and disruption of endothelial integrity. Exogenous H2S inhibited heme and Hb-mediated lipid oxidation of human atheroma-derived lipid and human complicated lesion. Our study suggests that the CSE/H2S system represents an atheroprotective pathway for removing or limiting the formation of oxidized Hb and lipid derivatives in the atherosclerotic plaque.

Impaired immunosuppressive effect of bronchoalveolar mesenchymal stem cells in hypersensitivity pneumonitis: Preliminary findings

Bronchoalveolar mesenchymal stem cells (MSCs) play an important role in the maintenance of lung integrity. Therapeutic application of bone marrow‐derived MSCs reduced chronic bronchial inflammation in idiopathic pulmonary fibrosis, and improved the ratio of survivors in sepsis with pneumonia. This study investigated the effect of MSCs from bronchoalveolar lavage fluid (BALF) of hypersensitivity pneumonitis (HP) on T‐cell function under in vitro conditions.