Identification of susceptibility loci for Takayasu arteritis through a large multi-ancestral genome-wide association study.

Takayasu arteritis is a rare inflammatory disease of large arteries. We performed a genetic study in Takayasu arteritis comprising 6,670 individuals (1,226 affected individuals) from five different populations. We discovered HLA risk factors and four non-HLA susceptibility loci in VPS8, SVEP1, CFL2, and chr13q21 and reinforced IL12B, PTK2B, and chr21q22 as robust susceptibility loci shared across ancestries. Functional analysis proposed plausible underlying disease mechanisms and pinpointed ETS2 as a potential causal gene for chr21q22 association. We also identified >60 candidate loci with suggestive association (p < 5 × 10-5) and devised a genetic risk score for Takayasu arteritis. Takayasu arteritis was compared to hundreds of other traits, revealing the closest genetic relatedness to inflammatory bowel disease. Epigenetic patterns within risk loci suggest roles for monocytes and B cells in Takayasu arteritis. This work enhances understanding of the genetic basis and pathophysiology of Takayasu arteritis and provides clues for potential new therapeutic targets.

Criteria sets for primary Sjogren's syndrome are not adequate for those presenting with extraglandular organ involvements as their dominant clinical features.

Patients with primary Sjogren's syndrome (pSS) may go undiagnosed or be misclassified due to the insidious nature and wide spectrum of the disease. The available several classification criteria emphasize glandular findings. We aimed to analyze the efficiency of various classification criteria sets in patients diagnosed on the clinical basis by expert opinion and to compare those pSS patients who fulfilled these criteria with those who did not. This is a multicenter study in which 834 patients from 22 university-based rheumatology clinics are included. Diagnosis of pSS was made on the clinical basis by the expert opinion. In this study, we only interviewed patients once and collected available data from the medical records. The European criteria, American-European Consensus Group (AECG) and American College of Rheumatology (ACR) Sjogren's criteria were applied. Majority of the patients were women (F/M was 20/1). The median duration from the first pSS-related symptom to diagnosis was significantly shorter in men (2.5 ± 2.3 vs 4.3 ± 5.9 years) (p = 0 < 0.016). When the European, AECG and ACR Sjogren's criteria were applied, 666 patients (79.9%) satisfied at least one of them. In total, 539 patients (64.4%) satisfied the European, 439 (52.6%) satisfied the AECG, and 359 (43%) satisfied the ACR criteria. Among the entire group, 250 patients (29.9%) satisfied all and 168 (20.1%) met none of the criteria. The rates of extraglandular organ involvements were not different between patients who met at least one of the criteria sets and those who met none. There is an urgent need for the modification of the pSS criteria sets to prevent exclusion of patients with extraglandular involvements as the dominant clinical features.

Identification of multiple genetic susceptibility loci in Takayasu arteritis.

Takayasu arteritis is a rare inflammatory disease of large arteries. The etiology of Takayasu arteritis remains poorly understood, but genetic contribution to the disease pathogenesis is supported by the genetic association with HLA-B*52. We genotyped ~200,000 genetic variants in two ethnically divergent Takayasu arteritis cohorts from Turkey and North America by using a custom-designed genotyping platform (Immunochip). Additional genetic variants and the classical HLA alleles were imputed and analyzed. We identified and confirmed two independent susceptibility loci within the HLA region (r(2) < 0.2): HLA-B/MICA (rs12524487, OR = 3.29, p = 5.57 × 10(-16)) and HLA-DQB1/HLA-DRB1 (rs113452171, OR = 2.34, p = 3.74 × 10(-9); and rs189754752, OR = 2.47, p = 4.22 × 10(-9)). In addition, we identified and confirmed a genetic association between Takayasu arteritis and the FCGR2A/FCGR3A locus on chromosome 1 (rs10919543, OR = 1.81, p = 5.89 × 10(-12)). The risk allele in this locus results in increased mRNA expression of FCGR2A. We also established the genetic association between IL12B and Takayasu arteritis (rs56167332, OR = 1.54, p = 2.18 × 10(-8)).

Salivary and serum B-cell activating factor (BAFF) levels after hydroxychloroquine treatment in primary Sjögren's syndrome.

PURPOSE: Some evidence implicates a role of hydroxychloroquine (HQ) in the management of Sjögren's syndrome. This study evaluated the effect of HQ on saliva B-cell activating factor (BAFF) levels as well as health related quality of life (QoL) in patients with primary Sjögren's syndrome (pSS). MATERIALS AND METHODS: Ten pSS patients who had been treated with HQ for at least 2 years and 15 healthy controls (HC) were included in the study. First, HQ was withdrawn for 12 weeks, then baseline evaluation was performed. Subsequently, HQ was restarted and further evaluations were carried out after 12 and 24 weeks of HQ treatment. Oral infection foci were eliminated by dental and periodontal treatments in both groups before enrollment. BAFF levels were evaluated with ELISA in serum and unstimulated mixed saliva. Salivary flow rates of patients and the control group were measured as well. Oral health quality of life (QoL) was evaluated by an oral health impact profile-14 (OHIP-14) questionnaire. RESULTS: Salivary BAFF levels (median: 12.39 ng/ml) were significantly decreased by using HQ both at 12 (2.78 ng/ml, P = 0.008) and 24 weeks (0.54 ng/ml, P = 0.011). Similarly, decreases in serum BAFF levels (5.23 ng/ml) were seen at 12 and 24 weeks after HQ treatment (2.18 ng/ml, P = 0.008 and 0.0 ng/ml, P = 0.012, respectively). Serum and salivary BAFF levels were significantly lower in healthy controls (0.37 ng/ml and 0.0 ng/ml, resp.) compared to those of pSS before HQ therapy (P = 0.006 and P = 0.001, resp.). Unstimulated salivary flows were similar in patients treated with HQ after 12 (0.38 ml/min) and 24 weeks (0.50 ml/min) (P = 0.51) but higher than the patients' rate at baseline (0.04 ml/min) (P = 0.008). CONCLUSION: Salivary and serum BAFF levels were lowered in patients with pSS when treated with HQ. In addition, decreased disease activity and increased salivary flows can be achieved with HQ in pSS patients.

PDCD1 polymorphisms are not associated with Takayasu's arteritis in Turkey.

OBJECTIVES: Takayasu's arteritis (TA) is a chronic arterial inflammation of unknown etiology involving mainly the aorta and its major branches. Based on the associations of programmed death-1 (PD-1) protein encoding gene (PDCD1) with connective tissue diseases and vasculitides, PDCD1 polymorphisms are studied for susceptibility to TA in this study. METHODS: The study group is made up of TA patients (n=229) fulfilling the 1990 ACR classification criteria and compared to 193 healthy controls (HC). PD-1.3, PD-1.5 and PD-1.6 single nucleotide polymorphisms of PDCD1 gene are genotyped by polymerase chain reaction and restriction analysis (PCR-RFLP). RESULTS: The distribution of PD-1.5 polymorphism in TA patients and HC revealed a similar presence of TT genotype in patients and controls (13.3% vs. 11.4%). PD-1.3 and PD-1.6 were less polymorphic and did not differ between the groups. Rare AA genotype of PD-1.3 (1.4% vs. 1.0%) and AG genotype of PD-1.6 was again similarly (22.4% vs. 19.2%) present in TA and HC. CONCLUSIONS: PD-1.3, 1.5 and 1.6 polymorphisms of PDCD1 gene, which were shown to be associated with various autoimmune disorders and vasculitides, are not associated with a susceptibility to TA in Turkish population.

Induced sputum as a method for detection of systemic sclerosis-related interstitial lung disease.

Inducted sputum (IS) is a non-invasive procedure that can be used for collection of airway secretions. The aim of our study is to evaluate the clinical usefulness of IS for detection of airway inflammation in systemic sclerosis (SSc). Bronchoalveolar lavage and IS were performed to 20 patients with SSc. Eighteen patients who were referred to pulmonary medicine for bronchoalveolar lavage due to other reasons were also recruited for cell counts comparisons. Spirometry, echocardiography and thorax CT (HRCT) imaging were also performed to all patients. Mean macrophage and lymphocyte counts were found to be increased in IS of SSc patients compared with that of control (58.4 ± 14.5% vs. 31.3 ± 16.3%, 30.2 ± 15.4% vs. 15.0 ± 11.5% P < 0.001), whereas mean neutrophil count was lower in the SSc patients (4.1 ± 4.5% vs. 17.2 ± 13.1%, P < 0.05). Significant correlations were noted between BAL and IS findings for macrophage (r = 0.55, P = 0.02) lymphocyte (r = 0.65, P < 0.01) and total cell counts (r = 0.45, P = 0.06). IS is an easy and reliable method for the detection of alveolitis and can be used for early detection of lung involvement in scleroderma.

Hydroxychloroquine improves dry eye symptoms of patients with primary Sjogren's syndrome.

The objective of the study is to investigate the effect of hydroxychloroquine (HCQ) on subjective and objective parameters of dry eye in patients with primary Sjogren's disease and to evaluate the association of tear fluid B-cell activating factor (BAFF) level with the response. Thirty-two patients with primary Sjogren's disease were enrolled in this prospective study. All patients included in the study completed at least a 48-month run-in period of using hydroxychloroquine. Patients were then instructed to drop the treatment for 3 months. Baseline and post cessation of treatment (baseline and 3 months) evaluations included, subjective symptom scoring, fluorescein and lissamine green staining, Schirmer's test, tear break-up time (BUT) and tear fluid BAFF assessments. Significant worsening was observed in, tear break up-time (TBUT) (7.9 ± 3.4 vs. 5.9 ± 2.9, P < 0.001) lissamine green of staining of the ocular surface (1.3 ± 0.9 vs. 1.8 ± 0.8, P < 0.01) and corneal fluorescein staining scores (2.2 ± 2.1 vs. 4.6 ± 3.3, P < 0.003) between on and off HCQ treatment, respectively. Similarly, gritty sensation and burning sensation were significantly changed at week 12 compared to baseline evaluation (1.18 ± 1.02 vs. 1.7 ± 1.05, P < 0.007 and 1.1 ± 1.0 vs. 1.6 ± 1.2, P < 0.0, respectively). Disease duration significantly correlated with baseline OSDI (r = 0.38, P < 0.04) and the average daily use of artificial tears (r = 0.36, P < 0.04). The mean BAFF levels were 0.8 ± 0.5 and 4.0 ± 0.7 ng/ml for baseline and week 12 evaluation, respectively (P < 0.0001). The results of this study suggest that HCQ may alleviate symptoms and signs of dry eye in pSS and decreases tear fluid BAFF levels.

Assessment of disease activity and progression in Takayasu's arteritis with Disease Extent Index-Takayasu.

OBJECTIVE: Disease Extent Index-Takayasu (DEI.Tak) is a new index developed for the follow-up of Takayasu's arteritis (TA), assessing only clinical findings without the requirement of imaging. We investigated the effectiveness of DEI.Tak in assessing disease activity and progression by comparing with physician's global assessment (PGA) and active disease criteria defined by Kerr et al. METHODS: The initial DEI.Tak forms were filled in for 145 TA patients cross-sectionally to detect the baseline damage and after 29.8 (31) months (n = 105, 144 visits) only by including the new/worsening symptoms within the past 6 months. RESULTS: At baseline, all patients had a DEI.Tak >0 [mean (s.d.): 7.6 (4.2)]. At this evaluation, 62% of the patients had active, 16.2% had persistent and 21.8% had inactive disease according to the PGA. At follow-up, in 69% of the patients the DEI.Tak score was 0. However, 14% of them were accepted as having active and 17% persistent disease according to PGA. In contrast, 18% with a DEI.Tak ≥ 1 were inactive according to PGA. Patients with active or persistent disease with PGA had higher DEI.Tak compared with inactives [1.3 (1.9), 1 (1.3) vs 0.2 (0.6), respectively; P < 0.001]. According to Kerr's criteria 27% were active. The total agreement between DEI.Tak and Kerr's criteria was 94% (κ = 0.85). Compared with PGA, Kerr's criteria had a total agreement of 74% and DEI.Tak 68%. CONCLUSION: During follow-up, most TA patients showed no clinical activity with DEI-Tak. Although the agreement between Kerr's criteria and DEI.Tak seemed very good, using Kerr's criteria instead of DEI.Tak increased the consistency with PGA, which could be explained by the influence of imaging data and acute-phase reactant levels on the physician's decisions.

Identification of Susceptibility Loci in IL6, RPS9/LILRB3, and an Intergenic Locus on Chromosome 21q22 in Takayasu Arteritis in a Genome-Wide Association Study.

OBJECTIVE: Takayasu arteritis is a rare large vessel vasculitis with incompletely understood etiology. This study was undertaken to perform the first unbiased genome-wide association analysis of Takayasu arteritis. METHODS: Two independent cohorts of patients with Takayasu arteritis from Turkey and North America were included in our study. The Turkish cohort consisted of 559 patients and 489 controls, and the North American cohort consisted of 134 patients and 1,047 controls of European ancestry. Genotyping was performed using the Omni1-Quad and Omni2.5 genotyping arrays. Genotyping data were subjected to rigorous quality control measures and subsequently analyzed to discover genetic susceptibility loci for Takayasu arteritis. RESULTS: We identified genetic susceptibility loci for Takayasu arteritis with a genome-wide level of significance in IL6 (rs2069837) (odds ratio [OR] 2.07, P = 6.70 × 10(-9)), RPS9/LILRB3 (rs11666543) (OR 1.65, P = 2.34 × 10(-8)), and an intergenic locus on chromosome 21q22 (rs2836878) (OR 1.79, P = 3.62 × 10(-10)). The genetic susceptibility locus in RPS9/LILRB3 lies within the leukocyte receptor complex gene cluster on chromosome 19q13.4, and the disease risk variant in this locus correlates with reduced expression of multiple genes including the inhibitory leukocyte immunoglobulin-like receptor gene LILRB3 (P = 2.29 × 10(-8)). In addition, we identified candidate susceptibility genes with suggestive levels of association (P < 1 × 10(-5)) with Takayasu arteritis, including PCSK5, LILRA3, PPM1G/NRBP1, and PTK2B. CONCLUSION: Our findings indicate novel genetic susceptibility loci for Takayasu arteritis and uncover potentially important aspects of the pathophysiology of this form of vasculitis.

Takayasu's arteritis is associated with HLA-B*52, but not with HLA-B*51, in Turkey.

INTRODUCTION: HLA-B*51 and HLA-B*52 are two close human leukocyte antigen (HLA) allele groups with minor amino acid differences. However, they are associated with two different vasculitides (HLA-B*51 in Behçet's disease and HLA-B*52 in Takayasu's arteritis (TAK)) and with major clinical and immunological differences. In this study, we aimed to screen a large cohort of TAK patients from Turkey for the presence of HLA-B*51 and HLA-B*52 as susceptibility and severity factors. METHODS: TAK patients (n = 330) followed at a total of 15 centers were included in the study. The mean age of the patients was 37.8 years, and 86% were women. DNA samples from the patients and healthy controls (HC; n = 210) were isolated, and the presence of HLA-B*51 or HLA-B*52 was screened for by using PCR with sequence-specific primers. RESULTS: We found a significant association of HLA-B*52 with TAK (20.9% vs HC = 6.7%, P = 0.000, OR = 3.7, 95% CI = 2.02 to 6.77). The distribution of HLA-B*51 did not differ between TAK patients and HCs (22.7% vs 24.8%, OR = 0.9, 95% CI = 0.60 to 1.34). The presence of HLA-B*52 decreased in late-onset patients (> 40 years of age; 12.0%, P = 0.024, OR = 0.43, 95% CI = 0.20 to 0.91). Patients with angiographic type I disease with limited aortic involvement also had a lower presence of HLA-B*52 compared to those with all other disease subtypes (13.1% vs 26%, P = 0.005, OR = 0.43, 95% CI = 0.23 to 0.78). CONCLUSIONS: In this study, the previously reported association of TAK with HLA-B*52 in other populations was confirmed in patients from Turkey. The functional relevance of HLA-B*52 in TAK pathogenesis needs to be explored further.

Tear osmolarity measurements in dry eye related to primary Sjögren's syndrome.

BACKGROUND: To evaluate the tear osmolarity in patients with dry eye syndrome related to primary Sjögren's Syndrome (SS). MATERIALS AND METHODS: Twenty eyes of 10 patients with dry eye and primary SS (Group 1) and 20 eyes of 20 subjects who do not have dry eye syndrome (Group 2) were included in this cross-sectional study. In all eyes, ophthalmic examination was performed in the same order: International Ocular Surface Disease Index survey, visual acuity assessment, conjunctival hyperemia scoring, tear osmolarity measurement with TearLab(™) Osmolarity System, tear film break-up time assessment, corneal fluorescein staining scoring, ocular surface Lissamine Green staining scoring, anesthetized Schirmer test. Dry eye severity was graded according to Dry Eye Workshop (DEWS) classification system. RESULTS: Four eyes with grade 1, four eyes with grade 2, seven eyes with grade 3, and five eyes with grade 4 dryness, according to DEWS system, were included. The mean tear osmolarity value was 301.9 ± 11.40 mOsm/L (range: 290-328) in Group 1, and 294.85 ± 8.33 mOsm/L (range: 283-311) in Group 2 (p = 0.03). In Group 1, tear osmolarity values were positively correlated with OSDI scores (r(18) = 0.55, r(2) = 0.31, p = 0.01), DEWS classification grades (r(18) = 0.73, r(2) = 0.54, p < 0.01), temporal and total corneal staining scores (r(18) = 0.67, r(2) = 0.44, p < 0.01, and r(18) = 0.51, r(2) = 0.26, p = 0.02, respectively), temporal conjunctival staining scores (r(18) = 58, r(2) = 0.34, p < 0.01); and negatively correlated with anesthetized Schirmer test results (r(18) = -0.62, r(2) = 0.38, p < 0.01) and TFBUT (r(18) = -0.50, r(2) = 0.25, p = 0.02). CONCLUSIONS: Tear osmolarity values were found to be greater in patients with dry eye syndrome related to primary SS compared to control subjects, and positively correlated with the severity of dry eye.

TRAF1/C5, eNOS, C1q, but not STAT4 and PTPN22 gene polymorphisms are associated with genetic susceptibility to systemic lupus erythematosus in Turkey.

A significant source of variability in the literature on systemic lupus erythematosus (SLE) susceptibility genes has been the inability to replicate genetic findings across different racial or ethnic groups. We investigated whether a single nucleotide polymorphism (SNP) of the STAT4 (rs7574865), PTPN22 (rs2476601), TRAF1/C5 (rs10818488), and C1q (rs292001) genes as well as the 27-bp VNTR polymorphism on intron 4 of eNOS, previously associated with SLE in other populations, are also associated with SLE risk in Turkey. A group of 158 SLE patients and 155 healthy controls were included in this study. A genetic association of the TRAF1/C5, C1q, and eNOS gene polymorphism, but not of STAT4 and PTPN22, was found to confer a degree of risk for SLE. These data highlight the importance of comparative studies in different populations to confirm the previously detected genetic associations.

Comparative performance analysis of 4 different anti-citrullinated protein assays in the diagnosis of rheumatoid arthritis.

OBJECTIVE: To evaluate the diagnostic performances of 2 recently developed assays, third-generation anti-cyclic citrullinated peptide (anti-CCP3) and anti-mutated citrullinated vimentin (anti-MCV), in comparison to conventional second-generation anti-cyclic citrullinated peptide (anti-CCP2) assay; and to assess a novel fully automated, random-access AxSYM anti-CCP assay for early diagnosis of rheumatoid arthritis (RA). METHODS: A cohort of 176 patients was enrolled in our study; 93 were diagnosed as having RA. The non-RA group consisted of 83 patients including 38 with systemic lupus erythematosus, 17 with primary Sjögren's syndrome, 11 with osteoarthritis, and 17 healthy controls. All were tested for presence of anti-CCP2, anti-CCP3, AxSYM anti-CCP, anti-MCV, and rheumatoid factor (RF)-IgM according to the manufacturers' instructions. RESULTS: Diagnostic performance of the assays revealed the highest area under the curve for the novel AxSYM anti-CCP [89.1; 95% confidence interval (CI) 84.3-93.8], followed by anti-CCP3 (86.7; 95% CI 81.6-91.9), anti-CCP2 (82; 95% CI 75.8-88.3), and anti-MCV (71.9; 95% CI 64.4-79.5). The sensitivities and specificities were 60.2% and 98.8% for anti-CCP2, 61.3% and 97.6% for anti-CCP3, 80.6% and 84.3% for AxSYM anti-CCP, 49.8% and 91.6% for anti-MCV, and 67.8% and 91.6% for RF-IgM, respectively. CONCLUSION: At cutoff of 5 U/ml, AxSYM anti-CCP emerged as a highly sensitive first-line early diagnostic tool for RA, with the greatest discrimination power, above 16 U/ml, in case of positive result. Using a single easily performed automated assay at 2 determined decision limits we were able to diagnose 81% of cases of RA and missing only 1.2%.

Mannose binding lectin levels in spondyloarthropathies.

OBJECTIVE: Mannose binding lectin (MBL), a member of the collectin family proteins, is a major molecule of the innate immune system; MBL deficiency is associated with increased susceptibility to infections. As gastrointestinal and genitourinary infections are suggested to be among the etiological factors of spondyloarthropathies (SpA), we investigated MBL deficiency in ankylosing spondylitis (AS) and undifferentiated SpA (uSpA). METHODS: One hundred seven patients with AS, 43 patients with uSpA, and 74 healthy controls were studied. Disease activity, radiological scores, and demographic features were recorded. MBL levels were measured with standard ELISA kits. RESULTS: Median MBL levels in AS, uSpA, and controls were 2705 (range 0-5861) ng/ml, 2897 (36-7586) ng/ml, and 3468 (0-7950) ng/ml, respectively. No significant differences were observed in median MBL levels and the prevalence of MBL deficiency between the groups. Bath AS Radiological Index scores were not affected by MBL levels. However, although statistically not significant, radiographic damage quantified by modified Stoke AS Spine Score (mSASSS) was 3 times higher in AS patients with MBL deficiency. Disease activity, clinical picture, and therapies were not associated with MBL levels. CONCLUSION: In AS patients with MBL deficiency, there was a tendency towards a more severe radiographic progression detected by mSASSS.

Comparative analysis of autoantibodies against a-fodrin in serum, tear fluid, and saliva from patients with Sjögren's syndrome.

OBJECTIVE: To evaluate levels of IgA and IgG antibodies against a-fodrin in serum, tear fluid, and saliva and compare them with anti-Ro and anti-La antibody levels in the same samples of patients with Sjögren's syndrome (SS). METHODS: Samples from 25 patients with SS (17 primary and 8 secondary), 8 patients with systemic lupus erythematosus (SLE), and 7 patients with rheumatoid arthritis (RA) as well as 20 healthy blood donor controls were collected. Antibodies were measured using ELISA. RESULTS: Although 40% of patients with primary SS had IgG anti-a-fodrin in their sera, it was also found in 36% and 32% of samples of their tear fluid and saliva, respectively. IgA a-fodrin antibodies were detected in 32% of SS sera, 20% of tear fluid samples, and 32% of saliva samples. Although the level of IgG anti-a-fodrin was significantly greater in serum, tear fluid, and saliva of SS patients compared to controls (p < 0.001), a significant difference was observed only in serum and saliva. While anti-Ro was detected in 48%, 56%, and 24% of serum, tear fluid, and saliva samples, respectively, anti-La was found in 40%, 44%, and 28%. Significant association was observed between serum IgG antibodies against a-fodrin and dry eye symptom score and rose bengal staining score. A negative association was also noted between tear IgA antibodies against a-fodrin and Schirmer I test. CONCLUSION: Correlation of IgG and IgA antibodies against a-fodrin with the severity of eye involvement suggests that these autoantibodies may be considered activation markers of SS.