Antibodies In Systemic Sclerosis Research Articles

Diversity and Epitope Spreading of Anti-RNA Polymerase III Antibodies in Systemic Sclerosis: A Potential Biomarker for Skin and Lung Involvement.

Epitope spreading (ES), involving autoantibodies, plays a crucial role in the development and persistence of autoimmune reactions in various autoimmune diseases. This study aimed to investigate the relationship between ES of anti-RNA polymerase III (RNAP III) antibodies (ARAs) and the clinical manifestations of systemic sclerosis (SSc). We investigated whether intermolecular ES occurs in the subunits of the RNAP III complex and whether intramolecular ES targets the major antigen, RNA polymerase III subunit A(RPC1), in patients with SSc. To achieve this, we synthesized 17 full-length subunit proteins of the RNAP III complex and 5 truncated forms of RPC1 in vitro using a wheat germ cell-free translation system. Subsequently, we prepared antigen-binding plates and measured autoantibodies in the serum of patients with SSc. Autoantibodies against different RNAP III complex subunits were found in patients who were ARA-positive with SSc. The intermolecular ES indicators significantly correlated with the modified Rodnan skin thickness score (mRSS) and surfactant protein-D, a biomarker of interstitial lung disease. However, the extent of disease on high-resolution computed tomography or pulmonary function tests did not show any significant correlation. Intramolecular ES indicator against RPC1 were significantly correlated with mRSS and renal crisis. Furthermore, longitudinal assessment of ES in RNAP III complex subunits correlated with mRSS and exhibited potential as a disease activity biomarker. Our findings indicate a correlation between ES levels and the severity of skin sclerosis or the risk of other complications in SSc. This study suggests that measuring ES in SSc serves as a novel biomarker for disease activity.

Phage Immunoprecipitation-Sequencing Reveals CDHR5 Autoantibodies in Select Patients With Interstitial Lung Disease.

Interstitial lung diseases (ILDs) are a heterogeneous group of disorders that can develop in patients with connective tissue diseases. Establishing autoimmunity in ILD impacts prognosis and treatment. Patients with ILD are screened for autoimmunity by measuring antinuclear autoantibodies, rheumatoid factors, and other nonspecific tests. However, this approach may miss autoimmunity that manifests as autoantibodies to tissue antigens not previously defined in ILD. We use Phage Immunoprecipitation-Sequencing (PhIP-Seq) to conduct an autoantibody discovery screen of patients with ILD and controls. We screened for novel autoantigen candidates using PhIP-Seq. We next developed a radio-labeled binding assay and validated the leading candidate in 398 patients with ILD recruited from two academic medical centers and 138 blood bank individuals that formed our reference cohort. PhIP-Seq identified 17 novel autoreactive targets, and machine learning classifiers derived from these targets discriminated ILD serum from controls. Among the 17 candidates, we validated CDHR5 and found CDHR5 autoantibodies in patients with rheumatologic disorders and importantly, patients not previously diagnosed with autoimmunity. Using survival and transplant free-survival data available from one of the two centers, patients with CDHR5 autoantibodies showed worse survival compared with other patients with connective tissue disease ILD. We used PhIP-Seq to define a novel CDHR5 autoantibody in a subset of select patients with ILD. Our data complement a recent study showing polymorphisms in the CDHR5-IRF7 gene locus strongly associated with titer of anticentromere antibodies in systemic sclerosis, creating a growing body of evidence suggesting a link between CDHR5 and autoimmunity.

Application of Immunoblot assay (ANA 23 Profile) for detection of autoantibodies in systemic sclerosis

Objective: Examine the clinical and subclinical characteristics and the rate of autoantibodies in systemic sclerosis (SSc) using Immunoblot technique (ANA 23 Profile). Research subjects and methods: Cross-sectional descriptive study of 57 patients diagnosed with SSc according to the 2013 American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) criteria and were tested for autoantibodies using the Immunoblot technique (ANA 23 Profile) at the National Hospital of Dermatology and Venereology. Results: Among 57 SSc patients, the female/male ratio was 5/1. The average age of disease onset was 49.3±13.3, with 57.9% of patients over the age of 50. Diffuse SSc was the most common (70%). Raynaud was the most common symptom (98.2%), followed by gastroesophageal reflux (86%), and pulmonary fibrosis (70.2%). Heart and kidney damage were less frequently observed, accounting for 15.8 and 5.3%, respectively. Positive rates of the three major antibodies in SSc included anti-Scl-70 antibody (63.2%), anti-centromere antibody (17.5%), and anti-RNA polymer III antibody (12.3%), respectively. Scl-70 autoantibodies were mainly found in diffuse skin types (91.7%) while CENP autoantibodies were mainly found in localised skin types (90%) with p<0.05. RNAP III antibodies were mainly found in diffuse skin types (85.7%), however, this difference was not statistically significant (p>0.05). Conclusion: The presence of Scl-70 was related to the diffuse skin types while the presence of CENP was related to localised skin types.

Clinical correlates of a subset of anti-fibroblast antibodies in systemic sclerosis

Anti-fibroblast antibodies (AFA) have been reported in systemic sclerosis (SSc) and are known to promote fibroblast activation. Aim of this study was to characterize the fine specificity of AFA and to analyze any correlations with clinical parameters associated to fibrosis. To this end, AFA were affinity-purified from a patient with diffuse cutaneous SSc (dcSSc) and interstitial lung disease (ILD). Panning of a phage display peptide library with purified AFA identified the motif <KxywxQ>. The peptide p121, bearing the AFA-specific motif, was used in ELISA to screen sera from 186 SSc patients and 81 healthy donors. Anti-p121 Ab serum levels were statistically higher in SSc than in healthy groups, and directly associated with dcSSc, reduced FVC (FVC < 70), and ILD. Given these clinical correlates, this study lays the groundwork for the identification of the antigen recognized by anti-p121 Ab, which might represent a novel therapeutic target for ILD.

Anti-carbamylated protein antibodies in systemic sclerosis

BackgroundTo investigate the presence of different isotypes of anti-carbamylated protein (CarP) antibodies in systemic sclerosis (SSc) patients and its association with skin involvement.MethodsSera of 194 SSc patients from the Leiden CCISS cohort, fulfilling ACR/EULAR 2013 criteria and a clinical diagnosis of SSc, 83 patients with other connective tissue diseases/Raynaud’s Phenomenon, 24 rheumatoid arthritis patients and 98 age and sex-matched healthy controls were tested for the presence of anti-CarP IgG, IgA and IgM, determined by ELISA. Clinical characteristics, that were evaluated in SSc patients, included age, anti-topoisomerase antibodies (ATA), anti-centromere antibodies (ACA) and modified Rodnan Skin Score (mRSS).ResultsThe SSc patients were 55 (SD:13) years and 155 (80%) were female. Forty-four (23%) patients tested positive for ATA, and 80 (42%) ACA. The median mRSS was 2 (range: 0; 47).Prevalence of anti-CarP IgG was higher in SSc patients than in healthy controls (8% vs 3%, p = 0.007. Prevalence of anti-CarP IgA and IgM and levels of anti-CarP isotypes were comparable between SSc patients and healthy controls.Fifteen (8%) SSc patients tested positive for anti-CarP IgG, 16 (8%) for anti-CarP IgA, and 36 (19%) for anti-CarP IgM. There were no significant correlations between age and levels of anti-CarP isotypes. No correlation between anti-CarP IgG levels and mRSS was found (r = 0.141, p = 0.049), nor for anti-CarP IgM and IgA levels. Anti-CarP IgA levels were higher in ATA compared to ACA positive SSc patients (ATA: 616 aU/ml [359; 1103]; ACA: 424 aU/ml [300; 673], p = 0.015).ConclusionSSc patients can test positive for Anti-CarP IgG, IgA and IgM. We do not observe a relevant clinical association between anti-CarP antibody response and skin involvement in SSc.

Antivinculin Antibodies in Systemic Sclerosis: Associations With Slow Gastric Transit and Extraintestinal Clinical Phenotype.

The gastrointestinal (GI) tract is commonly affected in systemic sclerosis (SSc). A positive association between antivinculin antibody levels and GI symptom severity is reported in SSc. We sought to examine whether antivinculin antibodies associate with measures of GI dysmotility and extraintestinal clinical phenotype in SSc. A total of 88 well-characterized patients with SSc and GI disease were assayed for antivinculin antibodies by enzyme-linked immunosorbent assay. Whole-gut scintigraphy, GI symptom scores, and clinical features of SSc were compared between patients with and without antibodies. Twenty of 88 (23%) patients had antivinculin antibodies, which were more prevalent in patients with slow gastric transit (35% versus 22%). In the univariate analyses, patients who were positive for antivinculin antibodies were more likely to have limited cutaneous disease (odds ratio [OR] 9.60 [95% confidence interval (95% CI) 1.19, 77.23]) and thyroid disease (OR 4.09 [95% CI 1.27, 13.21]). Such patients were also less likely to have lung involvement based on a Medsger Severity Score of ≥2 (OR 0.25 [95% CI 0.07, 0.92]). Higher levels of antivinculin autoantibodies were associated with less gastric emptying (β coefficient -3.41 [95% CI -6.72, -0.09]). The association between antivinculin antibodies and each of these clinical features remained significant in the multivariable model. In particular, the presence of antivinculin antibodies (β coefficient -6.20 [95% CI -12.33, -0.063]) and higher levels of antivinculin antibodies (β coefficient -3.64 [95% CI -7.05, -0.23]) were each significantly associated with slower gastric transit. Antivinculin antibodies associate with slower gastric transit in SSc and may provide insight into GI complications of SSc.

Anti-U11/U12 Antibodies as a Rare but Important Biomarker in Patients with Systemic Sclerosis: A Narrative Review

Anti-nuclear (ANA) are present in approximately 90% of systemic sclerosis (SSc) patients and are key biomarkers in supporting the diagnosis and determining the prognosis of this disease. In addition to the classification criteria autoantibodies for SSc [i.e., anti-centromere, anti-topoisomerase I (Scl-70), anti-RNA polymerase III], other autoantibodies have been associated with important SSc phenotypes. Among them, anti-U11/U12 ribonucleoprotein (RNP) antibodies, also known as anti-RNPC-3, were first reported in a patient with SSc, but very little is known about their association and clinical utility. The U11/U12 RNP macromolecular complex consists of several proteins involved in alternative mRNA splicing. More recent studies demonstrated associations of anti-anti-U11/U12 antibodies with SSc and severe pulmonary fibrosis as well as with moderate to severe gastrointestinal dysmotility. Lastly, anti-U11/U12 autoantibodies have been strongly associated with malignancy in SSc patients. Here, we aimed to summarize the knowledge of anti-U11/U12/RNPC-3 antibodies in SSc, including their seroclinical associations in a narrative literature review.

The impact of sex and anti-topoisomerase I antibodies in systemic sclerosis.

The study of sex-based differences in people with systemic sclerosis has grown in the past decade.1–5 Nevertheless, the genetic, biological, environmental, and socioeconomic factors driving these disparities and the resulting clinical implications have not been thoroughly investigated.

Anti-Th/To antibodies in systemic sclerosis: analysis of long-term follow-up of pulmonary involvement, organ damage accrual and mortality in an Italian cohort with a case-control study.

In systemic sclerosis (SSc) American patients, anti-Th/To antibodies were reported to be associated with interstitial lung disease (ILD) and pulmonary arterial hypertension (PAH). Few data in European patients are available, so we aimed at describing the clinical associations of anti-Th/To antibodies, focusing on ILD outcome, organ damage and mortality in an Italian single-centre cohort. Case-control study: anti-Th/To+ SSc patients vs. anti-topoisomerase (anti-topo)1+, anticentromere (ACA)+ and quadruple-negative (anti-topo 1-, ACA-, anti-RNAP3-, anti-Th/To-) SSc patients (1:3; matched for sex and age at SSc onset). Organ damage was assessed with the SCTC-Damage Index. Thirteen anti-Th/To+ patients were evaluated: 100% had limited cutaneous involvement; 46% digital ulcers; none had PAH, synovitis, joint contractures. As compared to anti-topo 1+ and quadruple-negative patients, anti-Th/To+ patients developed less frequently ILD (40% vs. 85% and 84%), that required less immunosuppression (8% vs. 41% and 44%), and rarely had functional worsening (15.4% at 5 years), without development of long-term complications (no need for O2, pulmonary hypertension, death). In anti-Th/To+ patients, the Damage Index was lower than in anti-topo 1+ and quadruple-negative patients at various timepoints, and remained low during the long-term follow-up (median: 16 years). The 5- and 10-year survival of anti-Th/To+ patients was 92% and 72%, respectively, and did not differ from those of the SSc matched patients; none of the anti-Th/To+ patients died due to SSc, while mortality was mainly related to cancer. In this study, anti-Th/To+ patients showed a mild SSc phenotype, characterised by low organ damage, favourable ILD outcome and good survival.

Biological and clinical insights from a randomized phase 2 study of an anti-oncostatin M monoclonal antibody in systemic sclerosis.

The cytokine oncostatin M (OSM) is implicated in the pathology of SSc. Inhibiting OSM signalling using GSK2330811 (an anti-OSM monoclonal antibody) in patients with SSc has the potential to slow or stop the disease process. This multicentre, randomized, double-blind, placebo-controlled study enrolled participants ≥18 years of age with active dcSSc. Participants were randomized 3:1 (GSK2330811:placebo) in one of two sequential cohorts to receive GSK2330811 (cohort 1: 100 mg; cohort 2: 300 mg) or placebo s.c. every other week for 12 weeks. The primary endpoint was safety; blood and skin biopsy samples were collected to explore mechanistic effects on inflammation and fibrosis. Clinical efficacy was an exploratory endpoint. Thirty-five participants were randomized to placebo (n = 8), GSK2330811 100 mg (n = 3) or GSK2330811 300 mg (n = 24). Proof of mechanism, measured by coordinate effects on biomarkers of inflammation or fibrosis, was not demonstrated following GSK2330811 treatment. There were no meaningful differences between GSK2330811 and placebo for any efficacy endpoints. The safety and tolerability of GSK2330811 were not favourable in the 300 mg group, with on-target, dose-dependent adverse events related to decreases in haemoglobin and platelet count that were not observed in the 100 mg or placebo groups. Despite a robust and novel experimental medicine approach and evidence of target engagement, anticipated SSc-related biologic effects of GSK2330811 were not different from placebo and safety was unfavourable, suggesting OSM inhibition may not be a useful therapeutic strategy in SSc. ClinicalTrials.gov, NCT03041025; EudraCT, 2016-003417-95.

Scleroderma-specific autoantibodies: Should they be included in the diagnostic work-up for Sjögren's syndrome?

ObjectivesSicca complaints are a frequent reason for rheumatologic consultation. Testing for specific antibodies against Ro/SSA and La/SSB antigens and minor salivary gland (MSG) biopsy are among the main tools implemented in the diagnostic work-up. Anticentromere antibodies and sicca manifestations are frequently detected in Sjögren's syndrome (SS) and systemic sclerosis (SSc), respectively. Herein, we aimed to determine the frequency and clinical associations of a wide spectrum of scleroderma (SSc)-specific autoantibodies in consecutive patients referred for evaluation of possible SS. MethodsDemographic, clinico-pathological, and laboratory data were recorded in 216 consecutive patients with sicca complaints. All study participants were tested for SSc-specific autoantibodies (against CENP, PM/Scl, Scl-70, Ku, NOR90, RP11, RP155, fibrillarin, PDGFR, and Th/To) using a commercially available immunoblot kit. According to band intensity, the identified autoantibodies were further classified in those with strong and medium titers. ResultsSSc-specific autoantibodies were detected in 41.7% (90/216) patients evaluated (19% at strong, 22.7% at medium titers) without significant differences between anti-Ro/SSA positive and negative groups. At strong titers was significantly higher in patients with MSG biopsies fulfilling SS histopathological criteria (30% vs 12.5%, p = 0.009). This association remained significant after adjustment for antibodies against Ro/SSA and La/SSB autoantigens [OR 95% (CI): 4.1 (1.5–10.6)]. ConclusionSSc-specific autoantibodies are frequently detected among patients presenting with sicca complaints and at strong but not medium titers are independently associated with MSG biopsy positivity. Taken together, these data imply a useful role of SSc antibody testing in the diagnostic work-up and possibly in the classification criteria for SS.

Fibrillarin antibodies in systemic sclerosis.

Fibrillarin antibodies in systemic sclerosis.

Anti-RNA polymerase III antibodies in systemic sclerosis: Multicentric study from Argentina

ObjectiveTo describe the frequency of anti-RNA polymerase III antibody in patients with Systemic Sclerosis (SSc) of a group of healthcare centres from Argentina and to explore differences among patients with positive and negative anti-RNA polymerase III antibody. Patients and methodsData from clinical records, anamnesis and physical examination were collected from 135 patients with SSc (ACR/EULAR 2013). A serum sample from each patient was obtained for the detection of anti-RNA polymerase III IgG antibodies by ELISA. ResultsIn all, 97.8% were women and the median age at diagnosis was 53 years (range 12–87), 77.7% had limited cutaneous SSc (lcSSC), 19,3% patients had diffuse cutaneous SSc (dcSSC) and 2.9% had scleroderma sine scleroderma. The 67.5% of the patients were from a Mestizos or Amerindian ethnic group. Anti-RNA polymerase III was positive in 5.9% of the patients. In 36 patients, the anticentromere (ACA) and anti-Scl70 antibodies were negative; anti-RNA polymerase III was positive in 16.7% of these 36 patients. Pitting scars and pulmonary artery hypertension were more frequent in anti-RNA polymerase III positive patients who were also older at diagnosis. No association with gastric antral vascular ectasia was found. The only patient with scleroderma renal crisis was anti-RNA polymerase III positive. ConclusionsAnti-RNA polymerase III frequency found in this study was one of the lowest reported, which could be related to the predominance of the Amerindian and Mestizo ethnic group. It is possible that the detection of anti RNA polymerase III allows better classification of SSc patients, to know their prognosis and to improve their follow-up, therefore more studies are needed.

Clinical significance of anti-NOR90 antibodies in systemic sclerosis and idiopathic interstitial pneumonia.

Anti-NOR90 antibodies are usually found in patients with SSc; however, their clinical relevance remains obscure. We developed an ELISA for measuring them to investigate the clinical features of patients with anti-NOR90 antibodies. Serum samples from 1252 patients with various conditions from Nagoya University Hospital and 244 patients with idiopathic interstitial pneumonia (IIP) from Tosei General Hospital were included. Anti-NOR90 antibodies were assayed by an ELISA using the recombinant protein produced by in vitro transcription/translation. Five (0.4%) patients in the Nagoya University Hospital cohort had anti-NOR90 antibodies. One patient with diffuse cutaneous SSc, three with limited cutaneous SSc, and one with Raynaud's disease were positive for anti-NOR90 antibodies. Anti-NOR90 antibodies were found more frequently in patients with systemic scleroderma-spectrum disorders (SSDs) than without SSDs (5/316 vs 0/936, P <0.00101) and were found more frequently in patients with SSc than without SSc (4/249 vs 0/528, P <0.0104) in the systemic autoimmune rheumatic diseases cohort. Three of the four anti-NOR90-positive SSc patients had interstitial lung disease (ILD), and two of those four had cancer. Three (1.2%) patients in the Tosei General Hospital cohort had anti-NOR90 antibodies. All three of the anti-NOR90-positive IIP patients had gastrointestinal tract involvement, and two of those three had cancer or skin lesions observed in SSc. Although anti-NOR90 antibodies are rarely found in clinics, our ELISA is useful for their detection. Further studies are needed to confirm the association of anti-NOR90 antibodies with ILD and cancer in SSc and IIP patients.

Anti-Polymyositis/Scl Antibodies in Systemic Sclerosis: Clinical Associations in a Multicentric Spanish Cohort and Review of the Literature.

To assess the clinical profile of patients with anti-polymyositis/Scl (PM/Scl) antibodies in a cohort of Spanish patients with systemic sclerosis. From the Spanish Scleroderma Study Group database, we selected patients in whom PM/Scl antibodies had been tested. We compared demographic, clinical, laboratory, and survival data between patients with and without PM/Scl antibodies. Seventy-two of 947 patients (7.6%) tested positive for PM/Scl antibodies. Patients with PM/Scl antibodies presented initially with more puffy fingers and arthralgias but less Raynaud phenomenon. Regarding cumulative manifestations, myositis and arthritis were more prevalent in patients with PM/Scl antibodies, as well as pulmonary fibrosis. On the contrary, patients with PM/Scl antibodies had less pulmonary hypertension. No difference in terms of survival at 5 and 10 years was noticed between the 2 groups. In systemic sclerosis patients from Spain, PM/Scl antibodies are associated with a distinct clinical profile. However, PM/Scl antibodies did not influence survival.

Significance of anti-tubulin-α-1C autoantibody in systemic sclerosis

OBJECTIVE To detect the serum level of a novel autoantibody, anti-tubulin-α-1C, in patients with systemic sclerosis (SSc) and to investigate its clinical significance. METHODS Anti-tubulin-α-1C antibody levels were determined by enzyme-linked immunosorbent assay (ELISA) in 62 patients with SSc, 38 systemic lupus erythematosus (SLE), 24 primary Sjogren's syndrome (pSS) patients, and 30 healthy controls (HCs). Erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), immunoglobulin A(IgA), immunoglobulin M (IgM), immunoglobulin G (IgG), C3, C4, rheumatoid factor (RF), antinuclear antibody(ANA), anti-centromere antibodies(ACA), anticardiolipin (aCL), anti-dsDNA antibody, anti-Sm antibody, anti-RNP antibody, anti-Scl-70 antibody, anti-Ro52 antibody, anti-SSA antibody, anti-SSB antibody, centromere protein A(CENP-A), centromere protein B (CENP-B) were measured by standard laboratory techniques. Raynaud's phenomenon and modified Rodnan skin score(MRSS) were recorded to evaluate the disease status of SSc. Independent sample t test, Chi square test, Mann-Whitney U test, Spearman rank correlation were used for statistical analyses. RESULTS The serum anti-tubulin-α-1C antibody concentration in SSc group was 81.24±34.38, the serum anti-tubulin-α-1C antibody concentration in SLE group was 87.84±38.52, the serum anti-tubulin-α-1C antibody concentration in pSS group was 59.79±25.24, and the serum anti-tubulin-α-1C antibody concentration in healthy group was 39.37±18.7. Multivariate analysis revealed that anti-tubulin-α-1C antibody levels were significantly increased in the SSc and SLE patients. The expression level of anti-tubulin-α-1C antibody in SSc was higher compared with the pSS group and the health control group (P < 0.01). Further analysis demonstrated that the elevated anti-tubulin-α-1C antibody were correlated with the SSc inflammation and disease activity markers ESR(r=0.313, P=0.019), The levels of anti-tubulin-α-1C antibody were also significantly correlated with MRSS(r=0.636, P < 0.01). The best cut-off value for the diagnose of SSc was 76.77 as mean+2SD value. The proportion of Raynaud's phenomenon was higher in the group of anti-tubulin-α-1C autoantibody-postive SSc patients than that in anti-tubulin-α-1C autoantibody negative group(71.4% vs. 37.5%, P=0.039). The proportions of anti-Scl-70 antibody, anti-CENP antibody and anti-cardiolipin antibody were higher in the group of anti-tubulin-α-1C autoantibody-postive SSc patients than in the anti-tubulin-α-1C autoantibody negative group (37.9% vs. 15.2%, 34.5% vs. 12.1%, 13.8 vs. 0, respectively, all P < 0.05). CONCLUSION Based on this explorative stu-dy, the level of anti-tubulin-α-1C antibody increased in the serum of the patients with SSc. There were correlations between anti-tubulin-α-1C autoantibody and clinical and laboratory indicators of the SSc patients. It may become a novel biomarker indicative of active SSc and could be applied in future clinical practice.

The prevalence and significance of anti-PM/Scl antibodies in systemic sclerosis.

Anti-PM/Scl (a-PM/Scl) antibodies are found in different systemic autoimmune diseases such as polymyositis, dermatomyositis, systemic sclerosis (SSc) and overlap syndromes. According to literature, they are detected in approx. 2% of SSc patients, but their presence is more common in SSc with myositis overlap. The aim of the study was to assess the prevalence of a-PM/Scl in patients with SSc and to identify differences in the clinical profile of the disease in patients with the presence of a-PM/Scl. The study was performed on 126 European Caucasian SSc patients (98 females and 28 males) hospitalized consecutively in the Department of Rheumatology and Connective Tissue Diseases. The study group was analyzed for the potential presence of a-PM/Scl using a commercial test - EUROLINE Systemic Sclerosis Profile. The detection and interpretation were carried out electronically using the specific Euroimmun - EUROLineScan programme. The subtype of SSc, incidence of internal organ involvement and serological profile were determined in the entire group. Due to the presence of a-PM/Scl, patients were divided into two groups: a-PM/Scl (+) SSc - 22 patients and a-PM/Scl (-) SSc - 104 patients. A-PM/Scl was detected in 22/126 patients with SSc (17.5%). A strong correlation was found between a-PM/Scl and myalgia or myositis (p = 0.0379), hand joints contractures (p = 0.0002) and the prevalence of overlap syndrome (p = 0.0142). There were no relationships between the presence of a-PM/Scl and subtypes of SSc, other organ involvement, digital ulcers or calcinosis. Anti-PM/Scl antibodies are fairly common in patients with systemic sclerosis. In SSc, anti-PM/Scl antibodies are frequently associated with myalgia or myositis, hand joint contractures and an overlap syndrome.

Extended myositis-specific and -associated antibodies profile in systemic sclerosis: A cross-sectional study

In systemic sclerosis (SSc) and idiopathic inflammatory myopathies (IIM), auto-antibodies are used in daily practice as potent biomarkers of clinical phenotypes. This study aimed at estimating the prevalence of myositis-specific (MSA) and myositis-associated (MAA) auto-antibodies in a well-characterised SSc patients cohort using two different immunoblot assays, and studying their clinical associations. In this cross-sectional study, the sera of 300 consecutive patients were tested at the same time with myositis antibodies Euroimmun® and D-tek® immunoblot assays. Prevalence of MSA/MAA, MSA and MAA were 17.0%, 8.0% and 9.7%, respectively. When combining results of both tests, anti-PM/Scl 100 were found in 5.0% (95% confidence interval 2.8; 8.1); anti-PM/Scl 75 and anti-TIF1γ in 3.7% (1.8; 6.5); anti-Ku 3.0% (1.4; 5.6); anti-MDA5 in 1.3% (0.4; 3.4); anti-Mi-2 β, anti-NXP2, anti-PL-7 and anti-SRP in 0.7% (0.08; 2.4); anti-EJ and anti-PL-12 in 0.3% (0.01; 1.8) of patients. No reactivity against SAE1, Jo-1 or OJ was observed. Anti-PM/Scl 75 antibodies were associated with interstitial lung disease (80% vs. 42%) and myositis (27% vs. 3%); anti-Ku antibodies were associated with myositis (33% vs. 3%). In this cross-sectional study of 300 SSc patients, the prevalence of MSA/MAA, MSA and MAA using immunoblot assays were 17.0%, 8.0% and 9.7%, respectively. MAA positivity was associated with ILD and myositis, but this study did not highlight any clinical associations with MSA positivity.

Prevalence and clinical association of the presence of anti-neutrophilic cytoplasmic antibody in systemic sclerosis.

IntroductionAnti-neutrophilic cytoplasmic antibody (ANCA) has been reported in systemic sclerosis (SSc). Some clinical features of SSc can also be presented with ANCA-associated vasculitis. Objectives were to determine the prevalence and clinical associations with ANCA among Thais with SSc.Material and methodsA cross-sectional study of Thai adult SSc patients was conducted. According to the sample size calculation, 185 patients were included. Clinical and laboratory tests for serology and others for evaluation of the clinical association with ANCA were done simultaneously on the study date.ResultsThe female to male ratio was 2 : 1. The majority had the diffuse SSc subset (71.2%). The respective prevalence of having a) at least 1 serological test for ANCA (viz., perinuclear ANCA, cytoplasmic ANCA, anti-myeloperoxidase, or anti-proteinase3), b) positive for either p-ANCA or c-ANCA, c) positive for either anti-MPO or anti-PR3, d) p-ANCA and anti-MPO and e) c-ANCA and anti-PR3 was 21.6% (95% CI: 15.9–28.3), 11.9% (95% CI: 7.6–17.4) and 13.0% (95% CI: 8.5–18.7) and 1% (95% CI: 0.1–3.9). By multivariate analysis, the erythrocyte sedimentation rate elevation was significantly associated with the presence of the antibody (OR = 11.36, 95% CI: 1.44–83.65), while elevation of high sensitivity cardiac troponin-T (hs-cTnT) was significantly associated with the presence of either p-ANCA or c-ANCA (OR = 4.25, 95% CI: 1.41–15.34). None of the patients had clinical features of systemic vasculitis.ConclusionsAround one-fifth of SSc patients have detectible ANCA without any features of vasculitis. The presence of ANCA is associated with inflammation and myocardial injury. ANCA is not antibody specific for vasculitis in SSc.

Clinical consequences of the presence of anti-RNA Pol III antibodies in systemic sclerosis.

IntroductionAnti-RNA polymerase III (a-RNA Pol III) antibodies are marker antibodies in patients with systemic sclerosis (SSc).AimTo assess the prevalence of a-RNA Pol III in patients with SSc and to identify the differences in the disease picture in SSc patients with and without a-RNA Pol III antibodies.Material and methodsThe study was performed in 126 SSc patients. The subtype of SSc, incidence of internal organ involvement, malignancy, death and serological profiles were determined in the entire group. The study groups were studied according to the presence of antibodies by applying the commercial test – EUROLINE SSc Profile. Due to the presence of a-RNA Pol III, patients were divided into two groups: the a-RNA Pol III (+) SSc group of 19 patients and the a-RNA Pol III (–) SSc group of 107 patients.ResultsA-RNA Pol III were present in 19/126 patients with SSc (15%), 13/19 (68.4%) patients had no other SSc marker antibodies. A-RNA Pol III were more common in patients with diffuse cutaneous SSc (p = 0.049). We showed a significant positive association between a-RNA Pol III and occurrence of malignancy (p = 0.007), scleroderma renal crisis (p = 0.001) and decreased DLCO (p = 0.007).ConclusionsAnti-a-RNA Pol III antibodies are common in patients with SSc, particularly with a diffuse subtype. In more than 50% of patients with a-RNA Pol III antibodies, they may be present as the sole marker of antibodies. In SSc, a-RNA Pol III antibodies are frequently associated with malignancy occurrence, kidney and lung involvement.