Coexistence of antitopoisomerase I and anticentromere antibodies in patients with systemic sclerosis

Pulmonary manifestations and prognosis of a cohort of patients with interstitial lung disease and positive to anti-Th/To autoantibodies

INTRODUCTION

Th/To autoantibody may be relevant in evaluating patients with interstitial lung disease (ILD) because the clinical diagnosis of systemic sclerosis (SSc) may not be evident. The study's objective was to describe manifestations and evolution of pulmonary function in a cohort of ILD patients positive for Th/To autoantibodies.

METHODS

ILD patients positive for anti-Th/To autoantibody were enrolled in this protocol. Baseline clinical features were registered, and survival analysis was performed to identify risk factors associated with worse survival.

RESULTS

Fifty-two patients positive for anti-Th/To autoantibodies with ILD were included. Only 21% of the patients fulfilled the ACR/EULAR 2013 systemic sclerosis classification criteria, and 63.4% fulfilled the IPAF ATS/ERS 2015 criteria. Twenty-five percent of the patients died during follow-up. Respiratory failure was the principal cause of death. Twenty-nine patients (56%) were positive for other hallmark SSc autoantibodies. The most frequent HRCT pattern was nonspecific interstitial pneumonia (NISP). Survival was strongly associated to the systolic pulmonary arterial pressure (sPAP), male sex and the extent of fibrosis in HRCT; besides, patients positive for other hallmark SSc autoantibodies had worse survival compared to those positive only to anti-Th/To. Seventy-six percent of them behaved as fibrotic progressive pulmonary disease, with an absolute decline of the FVC of at least 5%.

CONCLUSIONS

Only a small proportion of ILD patients positive for Th/To meet the criteria to be classified as SSc; however, most met criteria for IPAF. A high proportion of patients behave as progressive fibrotic pulmonary disease. Survival is associated with sPAP, the extent of lung disease, and the presence of other hallmark SSc autoantibodies.

The Autoantibody Array Assay: A Novel Autoantibody Detection Method

Systemic sclerosis (SSc) and dermatomyositis (DM) are autoimmune collagen diseases. Specific autoantibodies are known to be involved in their pathogeneses, each presenting with a different clinical manifestation. Although immunoprecipitation is the gold standard method for detecting autoantibodies, it is difficult to perform in all cases owing to the use of radioisotopes. In this study, we developed a new detection method for SSc and DM autoantibodies (A-cube) using cell-free protein synthesis and examined its validity. Proteins were synthesized using wheat germ cell-free protein synthesis. A total of 100 cases of SSc, 50 cases of DM, and 82 healthy controls were examined. The validity of the method was examined by a comparison with existing test results. Anti-centromere antibody, anti-topoisomerase I antibody, anti-RNA polymerase III antibody, anti-U1RNP anti-body, anti-Jo-1 antibody, anti-TIF1γ antibody, anti-Mi-2 antibody, and anti-ARS antibody were tested for. The results suggested that A-cube is comparable with existing testing methods or has a high sensitivity or specificity. In addition, there was a case in which the diagnosis was reconsidered using the A-cube. The quality of the A-cube was ensured, and its usefulness for a comprehensive analysis was demonstrated. The A-cube can therefore contribute to the clinical assessment and treatment of SSc and DM.

Advanced Autoantibody Testing in Systemic Sclerosis

Systemic sclerosis is a systemic autoimmune rheumatic disease characterized by immune abnormalities, leading to vasculopathy and fibrosis. Autoantibody testing has become an increasingly important part of diagnosis and prognostication. Clinicians have been limited to antinuclear antibody (ANA), antitopoisomerase I (also known as anti-Scl-70) antibody, and anticentromere antibody testing. Many clinicians now have improved access to an expanded profile of autoantibody testing. In this narrative review article, we review the epidemiology, clinical associations, and prognostic value of advanced autoantibody testing in people with systemic sclerosis.

Autoreactive B cell responses targeting nuclear antigens in systemic sclerosis: Implications for disease pathogenesis

A hallmark of disease pathogenesis of systemic sclerosis (SSc) is the presence of autoreactive B cell responses targeting nuclear proteins. Almost all SSc-patients harbour circulating antinuclear autoantibodies of which anti-topoisomerase 1, anti-centromere protein, anti-RNA polymerase III and anti-fibrillarin autoantibodies (ATA, ACA, ARA and AFA, respectively) are the most common and specific for SSc. In clinical practice, autoantibodies serve as diagnostic biomarkers and can aid in the identification of clinical phenotypes of the disease. However, factors driving disease progression in SSc are still poorly understood, and it is difficult to predict disease trajectories in individual patients. Moreover, treatment decisions remain rather empirical, with variable response rates in clinical trials due to patient heterogeneity. Current evidence has indicated that certain patients may benefit from B cell targeting therapies. Hence, it is important to understand the contribution of the antinuclear autoantibodies and their underlying B cell response to the disease pathogenesis of SSc.

Mouth opening in systemic sclerosis: Its course over time, determinants and impact on mouth handicap

Objective

Decreased maximal mouth opening is a common and disabling manifestation in systemic sclerosis patients. We aimed to study the course of maximal mouth opening, determinants of smaller maximal mouth opening over time and the burden of smaller maximal mouth opening on mouth handicap.

Methods

Consecutive systemic sclerosis patients participating in the prospective Leiden Combined Care in systemic sclerosis cohort were included. Annual clinical assessment included maximal mouth opening measurement and mouth handicap evaluation (Mouth Handicap in Systemic Sclerosis scale). Presence of microstomia (maximal mouth opening < 30 mm) was studied. Maximal mouth opening over time was assessed on group level and for all patients individually. Baseline characteristics were analysed for their association with smaller maximal mouth opening over time (linear mixed-effects models). Furthermore, cross-sectional association between maximal mouth opening with Mouth Handicap in Systemic Sclerosis scale was assessed (linear regression analysis).

Results

A total of 382 systemic sclerosis patients were studied with median follow-up time of 2.0 years (interquartile range = 0.0-3.0). At baseline, mean maximal mouth opening was 42.2 ± 8.0 mm and 7% suffered from microstomia. Annual decrease of > 5.0 mm in maximal mouth opening during follow-up occurred in 63 patients and was accompanied by increase in disease severity. Disease characteristics at baseline independently predictive for smaller maximal mouth opening over time were: more extended skin subtype; peripheral vasculopathy; pulmonary, renal and gastrointestinal involvement. Smaller maximal mouth opening was significantly associated with more reported mouth handicap.

Conclusion

The course of maximal mouth opening is stable in a majority of systemic sclerosis patients. Still, maximal mouth opening over time was smaller in patients with more severe organ involvement. Although microstomia was infrequent, a smaller maximal mouth opening was significantly associated with more mouth handicap, indicating the importance to address maximal mouth opening in routine care of systemic sclerosis patients.

Comprehensive autoantibody profiles in systemic sclerosis: Clinical cluster analysis

Background

Systemic sclerosis (SSc) belongs to the group of connective tissue diseases and is associated with the occurrence of disease-specific autoantibodies. Although it is still controversial whether these antibodies contribute to pathogenesis, there are new insights into the development of these specific antibodies and their possible pathophysiological properties. Interestingly, they are associated with specific clinical manifestations, but for some rarer antibodies this association is not fully clarified. The aim of this study is a comprehensive analysis of the serum autoantibody status in patients with SSc followed by correlation analyses of autoantibodies with the clinical course of the disease.

Methods

Serum from SSc patients was analyzed using a line blot (EUROLINE, EUROIMMUN AG) for SSc-related autoantibodies. Autoantibodies to centromere, Topo-1, antimitochondrial antibodies (AMA) M2 subunit, angiotensin II type 1 receptors (AT1R) and endothelin-1 type-A-receptors (ETAR) were also determined by ELISA. We formed immunological clusters and used principal components analysis (PCA) to assign specific clinical characteristics to these clusters.

Results

A total of 372 SSc patients were included. 95.3% of the patients were antinuclear antibody positive and in 333 patients at least one SSc specific antibody could be detected. Four immunological clusters could be found by PCA. Centromere, Topo-1 and RP3 all formed own clusters, which are associated with distinct clinical phenotypes. We found that patients with an inverted phenotype, such as limited cutaneous SSc patients within the Topo-1 cluster show an increased risk for interstital lung disease compared to ACA positive patients. Anti-AT1R and anti-ETAR autoantibodies were measured in 176 SSc patients; no association with SSc disease manifestation was found. SSc patients with AMA-M2 antibodies showed an increased risk of cardiovascular events.

Conclusion

In our in large cluster analysis, which included an extended autoantibody profile, we were able to show that serologic status of SSc patients provides important clues to disease manifestation, co-morbidities and complications. Line blot was a reliable technique to detect autoantibodies in SSc and detected rarer autoantibodies in 42% of our patients.

Combinations of scleroderma hallmark autoantibodies associate with distinct clinical phenotypes

Systemic sclerosis (SSc) is characterized by the presence of SSc-specific or SSc-associated antibodies (SSc-Abs): anti-topoisomerase I (ATA), anti-centromere (ACA), anti-RNA polymerase III (ARA), anti-U3RNP (U3RNP), anti-U1RNP (U1RNP), anti-PmScl (PmScl), anti-Ku (Ku) and anti-Th/To (Th/To), each being associated with specific clinical features and prognosis. The detection of more than one SSc-Abs in SSc patients is rare and only few data about these patients' clinical phenotype is available. The aim of our study was to evaluate the frequency and the disease's features associated with the presence of > 1 SSc-Abs positivity in a large cohort of SSc patients. The autoantibody profiles of 2799 SSc patients from February 2001 to June 2017 were retrospectively reviewed. Patients with > 1 SSc-Abs were identified. Clinical features were collected and compared to a large historical cohort of SSc patients with single SSc-Ab positivity. SSc patients were excluded if previously treated with rituximab, intravenous immunoglobulins or stem cell transplantation. Non-parametric tests were used for statistical analysis. Nearly 5% of SSc patients from our cohort had ≥ 2 autoantibody positivity, and 2.3% (n = 72) had ≥ 2 SSc-Abs positivity. Th e most common combination was U1RNP and ATA (35%). These patients were younger than patients with single autoantibody positivity and showed more commonly a diffuse cutaneous SSc form. They also had higher rates of overlap features compared to ATA patients. Other combinations included U1RNP and ACA (13%), ATA and ACA (7%) and U1RNP and PmScl (5%). In our study we observed that, while infrequently, SSc patients can present with a combination of two SSc-Abs and that the double positivity can influence their clinical phenotype compared to patients with single SSc-Ab positivity. The importance of re-testing SSc-Abs in patients with changing clinical phenotypes was also highlighted, as this may confer a differing risk stratification.

Coexistence of anti-topoisomerase I and anticentromere antibodies in a patient with systemic sclerosis. Efficacy of treatment combining rituximab and nintedanib. A case report

In the diagnostic of systemic sclerosis (SSc), both anti-centromere (ACA) and anti-topoisomerase I (ATA) antibodies are considered mutually exclusive, though their coexistence has been also reported in some patients. Notably, nintedanib has been approved for the treatment of interstitial lung disease associated to SSc. Herein, we present the clinical case of a 41-year-old woman with SSc who shows an immunological seroconversion (from ACA positivity to a coexistence of ACA and ATA antibodies) together with changes in her clinical phenotype. Besides, the patient responds positively to the treatment of her lung involvement with a combination of immunomodulators and antifibrotic agents.

Combining multi-antigenic immunodot with indirect immunofluorescence on HEp-2 cells improves the diagnosis of systemic sclerosis

Systemic sclerosis (SSc) is associated, in nearly all patients, with autoantibodies (Ab). Accordingly, and in order to identify major (anti-CEN A/B and anti-Topo I) but also minor Abs, the usefulness of combining indirect immunofluorescence (IIF) on HEp-2 cells with an 11 multi-antigenic SSc immunodot was explored. 1689 samples tested at the request of clinicians, were evaluated retrospectively. The positivity rate was 28.8% and the diagnosis of SSc was supported for 232 samples. Two groups of Abs were considered: group 1, Abs (anti-CENP A/B, anti-Topo I) present at elevated levels in SSc patients; group 2, Abs for which the Ab specificity (odds ratio and/or positive predictive value) was improved by using IIF on HEp-2 cells (RNA-Polymerase III, fibrillarin, Th/T0, PM-Scl). Altogether, this study highlights the utility of combining IIF on HEp-2 cells with the SSc immunodot as the first line of an SSc Abs detection/SSc diagnostic strategy.

Long-term evaluation of temporomandibular disorders in association with cytokine and autoantibody status in young women

Temporomandibular disorders (TMD) is a chronic pain disease affecting 4-60% of general population. Its suggested etiology includes mechanical overloading to related structures, psychosocial factors, and genetic vulnerability. However, its pathogenesis is yet to be fully understood, especially in cases with a higher level of pain and more associated comorbidities. Recently chronic systemic inflammation and possible autoimmunity has been indicated in several pain conditions as the underlying mechanism of chronicity but this aspect has not been rigorously investigated in TMD. This article focuses on analyzing the levels of cytokines, chemokines, autoantibodies and nonspecific inflammatory markers and comparing their levels according to pain severity and duration in 66 female TMD patients in their 20 s and investigating their association with clinical indices of TMD and comorbidities. The high pain disability group showed decreased range of jaw function and more pain on palpation of capsule areas compared to the low pain disability group. Comorbidities such as anxiety and sleep disturbance were also significantly more prevalent. The level of IL-8 and IgG were significantly higher in the high pain disability group. IL-2, -8, -13, IFN- γ, RANTES, PGE2, and thrombopoietin levels showed a significant effect on indices reflecting jaw function, generalized pain intensity, and health related quality of life. Such results imply that longer pain duration and higher pain intensity is associated with higher levels of systemic inflammation suggesting the possible role of immunologic disturbance as an underlying factor of chronic TMD pain and warranting further investigation for its consideration in diagnosis and treatment.

Anti-nuclear autoantibodies in systemic sclerosis : News and perspectives

Systemic sclerosis is a connective tissue disorder characterized by microvascular damage and excessive fibrosis of the skin and internal organs. One hallmark of the immunological abnormalities in systemic sclerosis is the presence of anti-nuclear antibodies, which are detected in more than 90% of patients with systemic sclerosis. Anti-centromere antibodies, anti-DNA topoisomerase I antibodies, and anti-RNA polymerase III antibodies are the predominant anti-nuclear antibodies found in systemic sclerosis patients. Other systemic sclerosis-related anti-nuclear antibodies include those targeted against U3 ribonucleoprotein, Th/To, U11/U12 ribonucleoprotein, and eukaryotic initiation factor 2B. Anti-U1 ribonucleoprotein, anti-Ku antibodies, anti-PM-Scl, and anti-RuvBL1/2 antibodies are associated with systemic sclerosis overlap syndrome. Anti-human upstream binding factor, anti-Ro52/TRIM21, anti-B23, and anti-centriole antibodies do not have specificity to systemic sclerosis, but are sometimes detected in sera from patients with systemic sclerosis. Identification of each systemic sclerosis-related antibody is useful to diagnose and predict organ involvement, since the particular type of systemic sclerosis-related antibodies is often predictive of clinical features, severity, and prognosis. The clinical phenotypes are largely influenced by ethnicity. Currently, an immunoprecipitation assay is necessary to detect most systemic sclerosis-related antibodies; therefore, the establishment of an easy, reliable, and simple screening system is warranted.

A cross-sectional study of autoantibody profiles in the Waikato systemic sclerosis cohort, New Zealand

The autoantibody profiles in New Zealand systemic sclerosis patients have not previously been reported. The aim of this study was to evaluate the autoantibody profiles of patients in the Waikato Hospital Systemic Sclerosis Clinic cohort. The EUROLINE (IgG) Systemic Sclerosis panel test kit (which tests for Scl-70, CENP-A, CENP-B, RP11, RP155, Fib, NOR90, Th/To, PM100, PM75, Ku, PDGFR and Ro-52) was selected for the purpose of this study. All patients attending the Waikato Hospital Systemic Sclerosis clinic were invited to participate. These patients were categorised by systemic sclerosis subtypes [1]. Results were compared with previously published data, including the EUSTAR database. Sixty patients (56 female) were recruited, with a median age of 61 years (range 29-81 years). Forty-one had limited cutaneous systemic sclerosis (lcSSc). Of these lcSSc patients, 31 (75.6%) were positive for CENP-A and CENP-B (anti-centromere) antibodies, 12 (29.3%) for Ro-52 antibodies, 5 (12.2%) for RP11 and RP155, 4 (9.8%) for Scl-70 and 1 (2.4%) each for anti-Fib and Th/To antibodies. Fifteen patients had diffuse cutaneous systemic sclerosis (dcSSc), of which 7 patients (47.6%) were positive for RP11 and RP155, 4 (26.7%) for Scl-70. Three dcSSc patients did not have either of these two major antibodies, but of these 15 dcSSc patients, 4 patients (26.7%) were positive also for Ro-52, 2 (13.3%) for anti-Ku, and 1 (6.7%) each for anti-Fib and NOR90. Four patients had overlap syndrome (OLS), 1 had CENP-A and CENP-B antibodies, 1 had Ro-52 autoantibodies 1 had anti-Ku antibodies. Three patients had no autoantibodies. This is the first study to look at the autoantibody profile of SSc patients in New Zealand. A higher prevalence of antibodies against centromere and RNA polymerase III was demonstrated in our group compared with the EUSTAR database suggesting that antibody prevalence may vary geographically.

The value of pattern capillary changes and antibodies to predict the development of systemic sclerosis in patients with primary Raynaud's phenomenon

The aim of this study is to assess the prognostic value of major provisional criteria for the development of systemic sclerosis (SSc) in primary Raynaud's phenomenon (RP) patients. We retrospectively studied the chart of 497 patients with primary RP in whom anticentromere (ACA) and antitopoisomerase I (ATA) antibodies tests and a capillary reading were available. Sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratios (LHR+), negative likelihood ratios (LHR-), odds ratio (OR), and area under the receiver operating characteristics curve (AUC) of those criteria were assessed to predict the development of SSc. During the average follow-up of 2.3 ± 1.9 years, 159 (32 %) patients evolved to SSc, 245 (49.3 %) evolved to other connective tissue diseases, and 93 (18.7 %) patients did not progress. The SSc pattern predicted SSc satisfactorily (LHR+ 4.12, LHR- 0.07, OR 63, AUC 0.819; P < 0.001). ACA were not significantly associated with the development of SSc (LHR+ 1.19, LHR- 0.9, OR 1.32, AUC 0.538, P = 0.156). ATA were significantly associated with the development of SSc (LHR+ 9.32, LHR- 0.67, OR 15.13, AUC 0.777; P < 0.001). Both SSc pattern and ACA or ATA were significantly associated with the development of SSc (LHR+ 2.98, LHR- 0.70, OR 4.2, AUC 0.674; P < 0.001 vs. LHR+ 16, LHR- 0.68, OR 24, AUC 0.819; P < 0.001, respectively). SSc pattern or ATA as independent risk factors, as well as following two parameters together (SSc pattern and ATA or SSc pattern and ACA) were good predictors for the development of SSc.

Systemic sclerosis: demographic, clinical and serological features in 100 Iranian patients

To evaluate demographic, clinical and laboratory features associated with scleroderma-specific auto-antibodies. Sera of 100 patients with systemic sclerosis (SSc) were analyzed by an indirect immunofluorescence technique with HEp-2 cells as a substrate. Specific ANA such as anti-centromere antibodies (ACA), anti-topoisomerase (TOPO), anti-RNA polymerase III (Pol 3), anti-U3-RNP (U3-RNP), anti-Th/To (Th/To) and anti-PM/Scl (PM/Scl) were detected by line immunoassay and anti-U1-RNP (U1-RNP) by ELISA. Frequency of clinical features associated with a specific antibody group was reported cumulatively over the follow-up period. Frequency of specific clinical features was compared across the two disease subtype including limited cutaneous (lcSSc) or diffuse cutaneous (dcSSc) as well as the auto-antibody groups. Ninety-four percent of patients were ANA positive with significant higher skin score, Raynauds and digital ulcer/gangrene. Anti-TOPO was detected in 71% of all patients, in 90.5% of dcSSC and in 65.8% of lcSSc. Anti-TOPO was significantly associated with dcSSc, higher skin score, digital ulcer/gangrene, pulmonary fibrosis, DLCO <70%. U1-RNP antibody was associated with lower fibrosis in lung. ACA was positive in 7% of patients and exclusively in those with lcSSc. We did not find association between gender and presence of auto-antibodies. Anti-TOPO antibody had a high prevalence in contrast to low prevalence of ACA antibody. There were no differences in clinical subtypes of the disease in patients with positive anti-TOPO and positive ACA. Differences in prevalence of auto-antibodies are suggestive of further genetic study.

Clinical Correlates of CENP-A and CENP-B Antibodies in a Large Cohort of Patients with Systemic Sclerosis

Objective.

To study the clinical phenotypes of centromeric proteins (CENP)-A- and CENP-B-positive patients with systemic sclerosis (SSc) and to compare them to anticentromere antibody (ACA)-positive and negative SSc patients.

Methods.

Sera samples were collected from 802 patients with SSc enrolled in a multicenter cohort study. Antibodies to CENP-A and B were detected by ELISA, and ACA by indirect immunofluorescence. Associations with clinical and other serological manifestations of SSc were investigated.

Results.

CENP-A antibodies were detected in 276 (34%), CENP-B in 286 (36%), and ACA in 279 (35%) patients. Patients having ACA, CENP-A, and/or CENP-B resembled each other and differed from the remainder of the cohort in the following respects: older chronologically and at disease onset; more commonly women; more likely to have limited disease and lower skin scores; less likely to have finger ulcers, digital tuft resorption, or finger contractures; more likely to have pulmonary hypertension; less likely to have interstitial lung disease, scleroderma renal crisis, inflammatory arthritis, and inflammatory myositis; and having lower overall disease severity. CENP-A and/or B status was predictive of the extent of skin involvement over time. Patients with limited disease who were CENP-A-negative at baseline were more likely to progress to diffuse disease compared to CENP-A-positive patients (OR 2.55, 95% CI 1.37, 4.85, p = 0.004).

Conclusion.

Clinical immunology laboratories are increasingly using high-throughput ELISA tests for CENP antibodies, with or without ACA detected by indirect immunofluorescence. The phenotype of CENP-A and/or B-positive patients is generally similar to that associated with ACA.

Capturing the heterogeneity in systemic sclerosis with genome-wide expression profiling

Heterogeneity in the clinical presentation and basic science findings of systemic sclerosis (SSc) has hindered the understanding of pathogenesis and development of effective treatments. Genome-wide profiling of SSc has measured this heterogeneity. Gene expression studies of diffuse SSc skin have shown reproducible, disease-specific gene expression signatures when compared with healthy controls and, surprisingly, disease-specific gene expression was found in both lesional and non-lesional skin. SSc-specific gene expression in peripheral blood cells and the lungs has also been demonstrated. Hypothesis-driven approaches that assess the contribution of individual pathways provide insight into the etiology of gene expression subsets.

Analysis of Class II human leucocyte antigens in Italian and Spanish systemic sclerosis

OBJECTIVE

To determine the role of Class II HLAs in SSc patients from Italy and Spain and in SSc patients of Caucasian ancestry.

METHODS

Nine hundred and forty-four SSc patients (Italy 392 patients; Spain 452 patients) and 1320 ethnically matched healthy controls (Italy 398 patients; Spain 922 patients) were genotyped up to the fourth digit by PCR with sequence-specific oligonucleotides for HLA-DRB1, DQA1 and DQB1 loci. Patients included 390 ACA-positive and 254 anti-topo I-positive subjects. Associations between SSc or SSc-specific antibodies and HLA alleles or HLA haplotypes were sought via the chi-square test after 10 000-fold permutation testing. A meta-analysis including this study cohort and other Caucasoids samples was also conducted.

RESULTS

In both the cohorts, the strongest association was observed between the HLA-DRB1*1104 allele and SSc or anti-topo I antibodies. The HLA-DRB1*1104 -DQA1*0501 -DQB1*0301 haplotype was overrepresented in Italian [odds ratio (OR) = 2.069, 95% asymptotic CIs (CI(95)) 1.486, 2.881; P < 0.001] and in Spanish patients (OR = 6.707, CI(95) 3.974, 11.319; P < 0.001) as well as in anti-topo-positive patients: Italy (OR = 2.642, CI(95) 1.78, 3.924; P < 0.001) and Spain (OR = 20.625, CI(95) 11.536, 36.876; P < 0.001). In both the populations we also identified an additional risk allele (HLA-DQB1*03) and a protective allele (HLA-DQB1*0501) in anti-topo-positive patients. The meta-analysis showed different statistically significant associations, the most interesting being the differential association between HLA-DRB1*01 alleles and ACAs (OR = 1.724, CI(95) 1.482, 2.005; P < 0.001) or topo I antibodies (OR = 0.5, CI(95) 0.384, 0.651; P < 0.001).

CONCLUSIONS

We describe multiple robust associations between SSc and HLA Class II antigens in Caucasoids that may help to understand the genetic architecture of SSc.

Frequency of disease-associated and other nuclear autoantibodies in patients of the German Network for Systemic Scleroderma: correlation with characteristic clinical features

Introduction

In the present study, we analysed in detail nuclear autoantibodies and their associations in systemic sclerosis (SSc) patients included in the German Network for Systemic Scleroderma Registry.

Methods

Sera of 863 patients were analysed according to a standardised protocol including immunofluorescence, immunoprecipitation, line immunoassay and immunodiffusion.

Results

Antinuclear antibodies (ANA) were detected in 94.2% of patients. In 81.6%, at least one of the autoantibodies highly associated with SSc or with overlap syndromes with scleroderma features was detected, that is, anti-centromere (35.9%) or anti-topoisomerase I (30.1%), followed in markedly lower frequency by antibodies to PM-Scl (4.9%), U1-ribonucleoprotein (U1-RNP) (4.8%), RNA polymerases (RNAPs) (3.8%), fibrillarin (1.4%), Ku (1.2%), aminoacyl-transfer RNA synthetases (0.5%), To (0.2%) and U11-RNP (0.1%). We found that the simultaneous presence of SSc-associated autoantibodies was rare (1.6%). Furthermore, additional autoantibodies were detected in 55.4% of the patients with SSc, of which anti-Ro/anti-La, anti-mitochondrial and anti-p25/p23 antibodies were most frequent. The coexistence of SSc-associated and other autoantibodies was common (43% of patients). SSc-associated autoantibodies disclosed characteristic associations with clinical features of patients, some of which were previously not acknowledged.

Conclusions

This study shows that five autoantigens (that is, centromere, topoisomerase I, PM-Scl, U1-RNP and RNAP) detected more than 95% of the known SSc-associated antibody responses in ANA-positive SSc patients and characterise around 79% of all SSc patients in a central European cohort. These data confirm and extend previous data underlining the central role of the determination of ANAs in defining the diagnosis, subset allocation and prognosis of SSc patients.

Anti-Scl-70 (topo-I) antibodies in SLE: Myth or reality?

Autoantibodies to topoisomerase I (topo-I, also referred to as Scl-70, ATA) have historically been considered a specific marker for systemic sclerosis (SSc). Although found in approximately 20% of SSc sera, other evidence indicated that ATA also occur in up to 25% of systemic lupus erythematosus (SLE). Given that SLE is approximately 100 times more prevalent than SSc, the number of ATA positive SLE patients is at least 2-3 orders of magnitude greater than the prevalence of ATA in SSc. These observations have raised questions about the disease specificity and clinical value of ATA. Therefore, our objective was to analyse the prevalence of ATA in different disease conditions with a special focus on SLE employing a systematic literature review (meta-analysis) in combination with our experimental investigations.

Clinical and serological evaluation of a novel CENP-A peptide based ELISA

Introduction

Anti-centromere antibodies (ACA) are useful biomarkers in the diagnosis of systemic sclerosis (SSc). ACA are found in 20 to 40% of SSc patients and, albeit with lower prevalence, in patients with other systemic autoimmune rheumatic diseases. Historically, ACA were detected by indirect immunofluorescence (IIF) on HEp-2 cells and confirmed by immunoassays using recombinant CENP-B. The objective of this study was to evaluate a novel CENP-A peptide ELISA.

Methods

Sera collected from SSc patients (n = 334) and various other diseases (n = 619) and from healthy controls (n = 175) were tested for anti-CENP-A antibodies by the novel CENP-A enzyme linked immunosorbent assay (ELISA). Furthermore, ACA were determined in the disease cohorts by IIF (ImmunoConcepts, Sacramento, CA, USA), CENP-B ELISA (Dr. Fooke), EliA^® CENP (Phadia, Freiburg, Germany) and line-immunoassay (LIA, Mikrogen, Neuried, Germany). Serological and clinical associations of anti-CENP-A with other autoantibodies were conducted in one participating centre. Inhibition experiments with either the CENP-A peptide or recombinant CENP-B were carried out to analyse the specificity of anti-CENP-A and -B antibodies.

Results

The CENP-A ELISA results were in good agreement with other ACA detection methods. According to the kappa method, the qualitative agreements were: 0.73 (vs. IIF), 0.81 (vs. LIA), 0.86 (vs. CENP-B ELISA) and 0.97 (vs. EliA^® CENP). The quantitative comparison between CENP-A and CENP-B ELISA using 265 samples revealed a correlation value of rho = 0.5 (by Spearman equation). The receiver operating characteristic analysis indicated that the discrimination between SSc patients (n = 131) and various controls (n = 134) was significantly better using the CENP-A as compared to CENP-B ELISA (P < 0.0001). Modified Rodnan skin score was significantly lower in the CENP-A negative group compared to the positive patients (P = 0.013). Inhibition experiments revealed no significant cross reactivity of anti-CENP-A and anti-CENP-B antibodies. Statistically relevant differences for gender ratio (P = 0.0103), specific joint involvement (Jaccoud) (P = 0.0006) and anti-phospholipid syndrome (P = 0.0157) between ACA positive SLE patients and the entire SLE cohort were observed.

Conclusions

Anti-CENP-A antibodies as determined by peptide ELISA represent a sensitive, specific and independent marker for the detection of ACA and are useful biomarkers for the diagnosis of SSc. Our data suggest that anti-CENP-A antibodies are a more specific biomarker for SSc than antibodies to CENP-B. Furthers studies are required to verify these findings.

Low prevalence of anti-RNA polymerase III antibodies in a French scleroderma population: anti-RNA polymerase III scleroderma

BACKGROUND

Anti-RNA polymerase III antibodies (anti-RNAP III) have been reported as potential immune markers of Systemic Sclerosis (SSc). Until now, their clinical use was disregarded because of technical difficulties to perform immunoprecipitation. Recently, ELISA kits became commercially available allowing an easy detection of anti-RNAP III. We intended to clarify the relevance of these antibodies in the diagnosis of SSc by ELISA detection.

METHODS

The prevalence of anti-RNAP III was analyzed using two ELISA kits in 50 consecutive SSc patients from Marseilles in South of France. Controls included 66 patients with other systemic autoimmune diseases, 34 viral diseases and 50 healthy subjects. Positive results with at least one ELISA kit were controlled by immunoprecipitation which is the reference assay.

RESULTS

In this study, positivity for anti-centromere and/or anti-topoisomerase I antibodies was observed in 84% of SSc patients. The prevalence of anti-RNAP III in SSc patients was 0% to 6% (3/50) depending on the ELISA kit and only 2% by immunoprecipitation. Concerning controls, two rheumatoid arthritis patients were positive using ELISA (6%), including one with immunoprecipitation confirmation. No anti-RNAP III was detected in systemic lupus erythematosus patients. Three blood donors and one viral disease control were positive using ELISA, but all were negative by immunoprecipitation.

CONCLUSIONS

Anti-RNAP III was rarely detected in a French population of SSc patients. Their prevalence was even lower than the one observed in rheumatoid arthritis controls. Therefore local immunologic profiles should be established before deciding a change in clinical practice for SSc immune screening.

Ethnic Influence on Disease Manifestations and Autoantibodies in Chinese-Descent Patients with Systemic Sclerosis

Objective.

To investigate ethnic influence on disease manifestations and autoantibody profile in patients of Chinese descent with systemic sclerosis (SSc).

Methods.

In a retrospective study of a multiethnic SSc cohort followed over a 17-year period, disease manifestations and autoantibody profile of patients of European and Chinese descent were compared.

Results.

There were 300 patients of European descent and 36 of Chinese descent, with similar proportions of women (81% and 72%, respectively) and patients with diffuse SSc (50% and 56%). Patients of Chinese descent [mean age ± standard deviation (SD) 52 ± 16 yrs; p = 0.05] were diagnosed at an older age compared to patients of European descent (mean ± SD 46 ± 12 yrs). Patients of Chinese descent compared to those of European descent had less frequent joint (69% vs 86%; p = 0.01) and gastrointestinal involvement (78% vs 94%; p = 0.004), but increased prevalence of myositis (17% vs 5%; p = 0.01). Patients of Chinese descent had less frequent digital ulceration (36% vs 55%; p = 0.04), and an absence of renal crisis. The frequency of cardiac and pulmonary involvement was similar in both groups. More patients of Chinese than of European descent were positive for anti-topoisomerase-I (47% vs 27%; p = 0.02), anti-Ro (36% vs 10%; p = 0.001), and anti-U1RNP (17% vs 5%; p = 0.03) antibodies. The observed differences for anti-topoisomerase-I, anti-Ro, and joint and gastrointestinal manifestations persisted in the subgroup analysis of patients matched for sex, disease subtype, and age at diagnosis.

Conclusion.

Patients of Chinese descent have milder SSc disease with less frequent joint and gastrointestinal manifestations, less severe vasculopathy, but increased prevalence of myositis and certain autoantibodies. Research is needed to identify determinants (genetic, environmental, and cultural factors) of the relationship between ethnicity and disease.

Clinical associations of anti-CENP-B and anti-Scl70 antibody levels measured by multiplexed fluorescent microsphere immunoassay in systemic sclerosis

The aim of this study was to assess the association between anti-CENP-B and anti-Scl70 antibody levels, measured by multiplexed fluorescent microsphere immunoassay, and the clinical features in patients affected by systemic sclerosis. Clinical evaluation of 80 scleroderma patients was performed in order to evaluate disease activity and organ involvement. Scleroderma-specific autoantibodies were detected using multiplexed fluorescent microsphere immunoassay. Unexpectedly, 11 patients resulted positive for both anti-Scl70 and anti-CENP-B antibodies; six cases showed a weak positivity for one of the two autoantibodies and a stronger positivity for the other one; five cases showed an intense positivity for both autoantibodies. This latter subgroup was excluded from the analysis of the associations between autoantibody levels and the clinical features. In the anti-CENP-B positive patients higher antibody levels were associated with a less extensive skin involvement in comparison with the cases affected by a more extensive skin involvement (521 +/- 208 vs 395 +/- 166 U/ml, respectively, P 0.038). In the anti-Scl70 positive patients autoantibody levels were directly correlated with skin involvement (P 0.018), showing higher levels in patients with a more extensive skin involvement in comparison with cases characterized by less extensive skin involvement (734 +/- 135 vs 490 +/- 183 U/ml, respectively, P 0.001). The findings of our study supports the association between autoantibody profile and disease severity in systemic sclerosis. In particular high levels of anti-Scl70 antibodies are associated with a worse cutaneous involvement, while high levels of anti-CENP-B antibodies seem to have a protective effect on skin manifestations.

Clinical characteristics of patients with both anti-U1RNP and anti-centromere antibodies

OBJECTIVE

To clarify the clinical characteristics of patients having both anti-U1RNP antibodies (anti-U1RNP) and anti-centromere antibodies (ACA) in comparison to subjects having either anti-U1RNP or ACA alone.

SUBJECTS AND METHODS

One hundred and fifty-six subjects who had anti-U1RNP and/or ACA were enrolled. They were classified into three groups: anti-U1RNP alone group (n = 64); ACA alone group (n = 82); and anti-U1RNP+ACA group (n = 10). The anti-U1RNP alone and ACA alone groups were also divided into the low-titre and the high-titre subgroups, respectively. The frequencies of the specific clinical findings and laboratory data were compared among the groups or subgroups.

RESULTS

The frequencies of persistent proteinuria or lupus nephritis (LN, 50.0%) and primary biliary cirrhosis (PBC, 30.0%) in the anti-U1RNP+ACA group were higher than that in the anti-U1RNP alone group (17.2%, p<0.01; 3.1%, p = 0.075; respectively). The frequencies of systemic lupus erythematosus (SLE, 60.0%), persistent proteinuria or LN (50.0%), anti-Ro (70.0%), and anti-La (30.0%) in the anti-U1RNP+ACA group were higher than those in the ACA alone group (11.0%, p<0.01; 4.9%, p<0.001; 23.2%, p<0.01; and 6.1%, p = 0.085; respectively). The frequency of systemic sclerosis (SSc) in the high-titre subgroup (30.0%) was higher than that in the low-titre subgroup (11.8%) in the anti-U1RNP alone group, without significance (p = 0.072). The frequency of interstitial pneumonia in the high-titre subgroup (26.8%) was higher than that in the low-titre subgroup (2.4%) in the ACA alone group (p<0.01).

CONCLUSIONS

The clinical characteristics of patients with anti-U1RNP+ACA were clarified in comparison to subjects having either anti-U1RNP or ACA alone.

Activity and potential role of licofelone in the management of osteoarthritis

Osteoarthritis is the most common form of arthritis. It is a progressive joint disease associated with aging. It may be found in the knees, hips, or other joints. It is estimated that costs associated with osteoarthritis exceed 2% of the gross national product in developed countries. Nonsteroidal anti-inflammatory drugs (NSAIDs) are a mainstay in the treatment of inflammatory disease and are among the most widely used drugs worldwide. The main limitation in using NSAIDs consists in their side-effects, including gastrointestinal ulcerogenic activity and bronchospasm. The mechanism of action of these drugs is attributed to the inhibition of cyclooxygenase (COX), and, consequently, the conversion of arachidonic acid into prostaglandins. It is hypothesized that the undesirable side-effects of NSAIDs are due to the inhibition of COX-1 (constitutive isoform), whereas the beneficial effects are related to the inhibition of COX-2 (inducible isoform). Arachidonic acid can also be converted to leukotrienes (LTs) by the action of 5-lipoxygenase (5-LOX). Licofelone, a LOX/COX competitive inhibitor, decreases the production of proinflammatory leukotrienes and prostaglandins (which are involved in the pathophysiology of osteoarthritis and in gastrointestinal (GI) damage induced by NSAIDs) and has the potential to combine good analgesic and anti-inflammatory effects with excellent GI tolerability. Preliminary data with this drug seem promising, but further well-designed clinical trials of this agent in the elderly will be necessary before a final evaluation is possible.

Sklerodermie-assoziierte Autoantikörper – klinische und diagnostische Relevanz

In systemic sclerosis (SSc) and its variants, autoantibodies are the best known immunological aberration. In more than 95% of the patients, antinuclear antibodies or other autoantibodies can be detected. In about 90% of SSc patients with antinuclear antibodies, scleroderma associated autoantibodies highly specific for systemic sclerosis are found. These autoantibodies usually exclude each other in individual patients, and they are detectable early, persisting during the course of the disease. SSc patients characterized by scleroderma associated autoantibodies belong to disease subsets which are relatively homogeneous in clinical, genetic and prognostic terms. Besides these diagnostically relevant autoantibodies, numerous additional ones have also been described. These are neither SSc specific nor mutually exclusive, and their antigens have only been partially characterized. Some, however, are thought to be relevant to the as yet unanswered question of whether autoantibodies are directly involved in SSc pathogenesis.

Autoantibodies in systemic sclerosis

OBJECTIVES

To describe the clinical, laboratory, and prognostic features associated with the scleroderma-specific autoantibodies.

METHODS

Using the Pittsburgh Scleroderma Databank, all consecutive patients seen between 1980 and 1995 who had autoantibody studies performed were studied. Anticentromere antibodies (ACA), antitopoisomerase (TOPO), anti-U1-RNP (U1-RNP), anti-RNA Polymerase III (Pol 3), anti-U3-RNP (U3-RNP), anti-Th/To (Th/To), and anti-Pm/Scl (Pm/Scl) were determined according to previously described methods. The frequency of clinical features, organ system outcomes, and survival within the patients with a specific antibody were cumulative over the course of the disease. The frequency of a specific feature was compared across groups to identify significant manifestations and outcomes in patients with a specific antibody.

RESULTS

Some demographic, clinical, and organ system findings were associated with the specific antibody, and other features with the scleroderma subtype (limited cutaneous or diffuse cutaneous scleroderma). U3-RNP, U1-RNP, and TOPO were seen more commonly in African-American patients, and ACA was seen in older, female Caucasians. Muscle inflammation was seen in patients with U1-RNP and U3-RNP. Digital tip ulcers and digital tuft resorption were seen more frequently in those with ACA and TOPO. A vasculopathy causing pulmonary hypertension typically occurs with ACA and pulmonary fibrosis with TOPO; however, both types of lung disease were seen in patients with nucleolar antibodies, Th/To and U3-RNP. Importantly, severe interstitial fibrosis was rarely seen in cases with Pol 3. Renal crisis was strongly associated with Pol 3. Survival within limited scleroderma was decreased in the Th/To patients compared with ACA patients. Within the diffuse scleroderma group, patients with Pol 3 had the best survival.

CONCLUSIONS

Scleroderma autoantibodies are associated with very specific demographic, clinical, organ system, and survival features.

RELEVANCE

The determination of scleroderma autoantibodies may be helpful in assessing the prognosis, monitoring, and treatment of scleroderma patients.

Intérêt des anticorps antinucléaires pour le diagnostic, la classification et le pronostic de la sclérodermie systémique

PURPOSE

Systemic sclerosis (SSc) like other connective tissue diseases is characterized by the occurrence of antinuclear auto-antibodies (ANA). We reviewed the diagnostic value and prognostic value of ANA in SSc.

CURRENT KNOWLEDGE AND KEY POINTS

LeRoy proposed new criteria of limited forms of SSc which take into account the immunological profile of the patients. Anticentromere, antitopoisomerase I, antifibrillarin, anti-PM-Scl, antifibrillin or anti-RNA-polymerase I or III are considered as specific anti-autobodies. Whereas anticentromere antibodies are more associated with limited SSc and antitopoisomerase I with diffuse SSc, other auto-antibodies were associated with other organ involvement : anti-RNA-polymerase I or III and renal crisis, anti-U1-RNP and pulmonary hypertension and pulmonary fibrosis, etc. Patient with persistent antitopoisomerase I antibodies have a poor survival, those with antitopoisomerase antibodies that disappear with time have a better prognosis.

FUTURE PROSPECTS AND PROJECTS

A better identification of the patients with SSc, an individual biological profile and organ involvement may help better management of the disease and better access to clinical trials. The development of new immunological tests and their clinical application should help us in that way.

Nailfold videocapillaroscopic patterns and serum autoantibodies in systemic sclerosis

BACKGROUND

Microvascular lesions are a predominant feature in systemic sclerosis (SSc) and seem to play a central pathogenetic role. Recently, we graded scleroderma microangiopathy by nailfold videocapillaroscopy (NVC) into three NVC patterns (early, active and late). The aim of the present study was to confirm, in a larger number of SSc patients, the presence of three patterns of microvascular damage, and to detect any possible relationship between these patterns and both specific serum autoantibodies and the subsets of cutaneous involvement.

METHODS

Two hundred and forty-one consecutive patients (227 women and 14 men) affected by SSc were recruited. One hundred and forty-eight patients were affected by limited cutaneous SSc (lSSc) and 93 patients by diffuse cutaneous SSc (dSSc). The ages at onset of Raynaud's phenomenon (RP) and SSc, the durations of RP and SSc, ANA and antitopoisomerase I (anti-Scl70) and anticentromere (ACA) antibodies were investigated in all patients. The SSc patients were subdivided on the basis of the NVC pattern into three groups.

RESULTS

A statistically significant correlation was found between the NVC patterns and the durations of both RP and SSc (P<0.001). Enlarged and giant capillaries, together with haemorrhages, constituted the earliest NVC finding in SSc (early NVC pattern). These abnormalities were mostly expressed in the active NVC pattern. Loss of capillaries, ramified capillaries and vascular architectural disorganization were increased in the late NVC pattern. Age and the duration of both RP and SSc were lower in 24 patients complaining of RP alone. Anti-Scl70 antibodies were statistically less frequent in the early vs both the active and the late NVC pattern, whereas no significant correlation was found between the presence of anti-Scl70 antibodies and the duration of either RP or SSc. ACA positivity was more frequent in patients with longer RP duration. Patients with lSSc had shorter SSc duration and showed the early or active NVC pattern more frequently. Conversely, patients with dSSc showed longer disease duration and mostly showed the late NVC pattern.

CONCLUSIONS

NVC is an appropriate tool for differential diagnosis between primary and secondary RP through the clear recognition of the early NVC scleroderma pattern. This study confirms, in a large number of SSc patients, the existence of three distinct NVC patterns that might reflect the evolution of SSc microangiopathy. The presence of anti-Scl70 antibodies seems be related to earlier expression of the active and late NVC patterns of SSc microvascular damage. The presence of ACA seems to be related to delayed expression of the late NVC pattern.

Autoimmunity in scleroderma: the origin, pathogenetic role, and clinical significance of autoantibodies

PURPOSE OF REVIEW

Systemic sclerosis, or scleroderma, is a systemic autoimmune disease manifest by vascular damage and fibrosis within the skin and visceral organs. Whereas scleroderma is a heterogenous disorder in terms of disease symptoms and clinical course, scleroderma-specific autoantibody profiles associate strongly with distinct clinical phenotypes, making serologic testing of great diagnostic aid. This review will focus on the clinical significance and the potential pathogenic role of autoantibodies in scleroderma.

RECENT FINDINGS

Novel autoantibody and phenotype associations discovered within the past year underscore the clinical utility of systemic sclerosis-associated autoantibodies. Whereas autoantibodies are generally believed to indicate the presence of ongoing tissue damage, some research suggests that the humoral immune response may play a role in generating such damage.

SUMMARY

Improvements in multiplex autoantibody assays will aid in the diagnosis and prognosis of the complications associated with systemic sclerosis. Continued research into autoantibody/phenotype associations could also yield critical insights into the pathogenesis of, and suggest novel therapeutic targets for, this chronic, debilitating disease.

Musculoskeletal involvement in scleroderma

Scleroderma can be accompanied by arthralgias, inflammatory arthritis, flexion contractures, nerve entrapment, myositis, or myopathy. Antibodies in scleroderma can occur in other connective tissue diseases; overlap syndromes between scleroderma and Sjogren's syndrome, lupus, and rheumatoid arthritis are reported. Many of the musculoskeletal symptoms in scleroderma are treated symptomatically; most treatments are not proven in randomized controlled trials in these patients. Musculoskeletal manifestations are a major cause of morbidity and disability in scleroderma.

Development of a CENP-A/CENP-B-specific immune response in a patient with systemic sclerosis

Antibodies directed against an epitope motif on CENP-A have been shown to cross-react with mimotopes on other autoantigens and on Epstein-Barr nuclear antigen 1 (EBNA-1), suggesting a molecular mimicry. We describe here the gradual development of an anticentromere immune response in a patient with systemic sclerosis, which started from an antihistone response and was not mediated by molecular mimicry. Via an epitope on histone H3, the antibody response spread to a homologous epitope in the H3 homology domain of CENP-A. This was followed by an intramolecular epitope spreading to N-terminal peptides of CENP-A containing the known epitope motif G-P-X(1)-R-X(2). From there it spread to corresponding epitopes on CENP-B and to mimotopes of the major CENP-A epitope motif on other autoantigens including EBNA-1. Whether the D-penicillamine treatment received by this patient was involved in the triggering of this cascade remains a matter of speculation.