Autoantibody profiles in systemic sclerosis: Predictive value for clinical evaluation and prognosis

Managing Symptoms of Systemic Sclerosis for the Allergist-Immunologist

PURPOSE OF REVIEW

Systemic sclerosis (SSc) is a chronic, multisystem, autoimmune disease characterized by fibrosis, vasculopathy and immune system dysregulation. We provide a comprehensive review of features of systemic sclerosis that can potentially present to the allergist.

RECENT FINDINGS

A thorough understanding of the management options is crucial for clinicians involved in the care of patients with SSc to optimize clinical outcomes. Management of systemic sclerosis has drastically changed in the last decade and continues to evolve. This review provides an overview of management strategies for the various symptoms including skin, upper and lower airway, gastrointestinal and vascular manifestations. Institution of treatment early in the disease, including referral to rheumatology or specialized scleroderma centers, can help to both prevent and manage disease complications, and improve patient quality-of-life. While the landscape of systemic sclerosis management has evolved, we continue to recognize that there is still a need for better biomarkers and targeted therapies.

Significance of Systemic Scleroderma-Specific Autoantibodies in Idiopathic Interstitial Pneumonia

Objective Patients with idiopathic interstitial pneumonia (IIP) often test positive for systemic scleroderma-specific autoantibodies (SSc-Ab), even if they do not meet the diagnostic criteria for systemic scleroderma (SSc). However, the significance of SSc-Ab in IIP is unknown. Methods We retrospectively studied the medical records of all patients suspected of interstitial lung disease (ILD) who visited our center between January 2016 and December 2021. We evaluated the association between SSc-Ab subtypes and clinical characteristics, prognosis, and incidence of acute exacerbation (AE) of IIP. Among 571 patients suspected of having IIP and SSc-Ab measured, we excluded cases with clear causes of ILD or those diagnosed with other diseases and analyzed 386 cases diagnosed as IIP. Results Among 386 IIP patients, 48 were SSc-Ab positive (platelet-derived growth factor receptor (PDGFR) in 0, Th/To in 10, anti-nucleolar organizer region 90 antibodies (NOR90) in 12, fibrillarin in five, RP155 in 14, RP11 in three, CENP A in seven, CENP B in 10, and Scl-70 in six). There was no significant difference in survival rate or incidence of AE between patients with or without SSc-Ab. Multivariate logistic regression analysis showed that age and malignancy were significant risk factors for death, whereas age, male sex, and anti-fibrillarin antibodies were significant risk factors for AE of IIP. Conclusion None of the SSc-Abs were associated with the risk of mortality, and anti-fibrillarin antibodies, along with age and male sex may contribute to the risk of AE of IIP, predicting severe lung involvement and warranting multidisciplinary treatment and careful follow-up.

Emerging diagnostic and therapeutic challenges for skin fibrosis in systemic sclerosis

Systemic sclerosis (also called scleroderma, SSc) is a chronic autoimmune disorder characterized by excessive collagen deposition leading to skin fibrosis and various internal organ manifestations. The emergent diagnostics and therapeutic strategies for scleroderma focus on early detection and targeted interventions to improve patient outcomes and quality of life. Diagnostics for SSc have evolved significantly in recent years, driven by advancements in serological markers and imaging techniques. Autoantibody profiling, especially antinuclear antibodies (ANA) and specific scleroderma-associated autoantibodies, aids in identifying subsets of scleroderma and predicting disease progression. Furthermore, novel imaging modalities, such as high-frequency ultrasonography and optical coherence tomography, enable early detection of skin fibrosis and internal organ involvement, enhancing the diagnostic precision and allowing for tailored management. Therapeutic strategies for SSc are multifaceted, targeting immune dysregulation, vascular abnormalities, and fibrotic processes. Emerging biologic agents have shown promise in clinical trials, including monoclonal antibodies directed against key cytokines involved in fibrosis, such as transforming growth factor-β (TGF-β) and interleukin-6 (IL-6). Additionally, small-molecule inhibitors that disrupt fibrotic pathways, like tyrosine kinase inhibitors, have exhibited potential in limiting collagen deposition and preventing disease progression. Stem cell therapy, cell ablation and gene editing techniques hold great potential in regenerating damaged tissue and halting fibrotic processes. Early intervention remains crucial in managing SSc, as irreversible tissue damage often occurs in advanced stages. Novel diagnostic methods, such as biomarkers and gene expression profiling, are being explored to identify individuals at high risk for developing progressive severe disease and intervene proactively. Furthermore, patient-tailored therapeutic approaches, employing a combination of immunosuppressive agents and targeted anti-fibrotic therapies, are being investigated to improve treatment efficacy while minimizing adverse effects. The emergent diagnostics and therapeutic strategies in scleroderma are transforming the management of this challenging disease. Nevertheless, ongoing research and clinical trials are needed to optimize the efficacy and safety of these novel approaches in the complex and diverse spectrum of SSc manifestations.

GWAS for systemic sclerosis identifies six novel susceptibility loci including one in the Fcγ receptor region

Here we report the largest Asian genome-wide association study (GWAS) for systemic sclerosis performed to date, based on data from Japanese subjects and comprising of 1428 cases and 112,599 controls. The lead SNP is in the FCGR/FCRL region, which shows a penetrating association in the Asian population, while a complete linkage disequilibrium SNP, rs10917688, is found in a cis-regulatory element for IRF8. IRF8 is also a significant locus in European GWAS for systemic sclerosis, but rs10917688 only shows an association in the presence of the risk allele of IRF8 in the Japanese population. Further analysis shows that rs10917688 is marked with H3K4me1 in primary B cells. A meta-analysis with a European GWAS detects 30 additional significant loci. Polygenic risk scores constructed with the effect sizes of the meta-analysis suggest the potential portability of genetic associations beyond populations. Prioritizing the top 5% of SNPs of IRF8 binding sites in B cells improves the fitting of the polygenic risk scores, underscoring the roles of B cells and IRF8 in the development of systemic sclerosis. The results also suggest that systemic sclerosis shares a common genetic architecture across populations.

Absence of interstitial lung disease at initial visit may predict a favorable outcome for Japanese patients with systemic sclerosis with anti-topoisomerase I antibody

Interstitial lung disease (ILD) is recognized a prognostic factor and leading cause of death in patients with systemic sclerosis (SSc). The aim of the present study is to clarify factors at an initial visit that are associated with the deterioration of ILD in SSc patients with anti-topoisomerase I (anti-topo I) antibodies. This was a single-center, retrospective, observational study. Fifty-three consecutive SSc patients with anti-topo I antibodies were included in this study. Of the 53 patients, 43 had ILD at their initial visit, whereas 10 did not. We examined the clinical and immunological factors at an initial visit that were associated with the deterioration of ILD. The deterioration of ILD was defined as the administration of intravenous cyclophosphamide (IVCY) therapy. In this cohort, 45 (85%) patients had ILD at the time of the final observation, and only two who did not have ILD at their initial visit developed ILD during the follow-up period. Until the final observation, 26 (49%) patients received IVCY therapy for the progression of ILD. The age at onset, disease duration, SSc subtype, and skin score were similar between patients with and those without IVCY therapy. Approximately 60% (26 of 43) of patients with ILD at their initial visit received IVCY therapy. On the other hand, none of the 10 patients without ILD at their initial visit received IVCY therapy. Our multivariate analyses using Cox proportional hazards regression model revealed that the presence of ILD at an initial visit was an independent factor associated with the introduction of IVCY therapy (odds ratio, 2.8e+7 [95% confidence interval, 1.8e+17-uncalculated], p = 0.0048). Although anti-topo I antibodies are strongly associated with ILD, it was unlikely for SSc patients with anti-topo I antibodies to receive IVCY therapy when they did not have ILD at an initial visit.

Role of rituximab in the treatment of systemic sclerosis: A literature review

This literature review aimed to evaluate the effectiveness of rituximab (RTX) in patients with systemic sclerosis (SSc). PubMed was searched for articles, published through 31 March 2022, on any controlled studies using RTX in the treatment of SSc. Of 85 identified articles, 9 were selected by title/abstract screening and full text examination. All nine articles reported outcomes of forced vital capacity (%FVC), and seven reported those of modified Rodnan skin scores (mRSS). The results showed that among the seven controlled studies evaluating skin lesions in patients with SSc, four showed a significant improvement of mRSS by RTX when compared with a control group, whereas three showed no significant effect. Among the nine controlled studies evaluating lung lesions, five showed a significant improvement of %FVC compared with a control group, whereas four showed no significant effect. In conclusion, RTX may be effective in the treatment of skin and lung lesions in patients with SSc. The profiles of SSc patients for whom RTX was indicated were unclear, although patients with diffuse cutaneous SSc and those positive for anti-topoisomerase I antibody were considered potential targets. Additional studies are needed to assess the long-term effectiveness of RTX in the treatment of patients with SSc.

Autoantibodies Which Bind to and Activate Keratinocytes in Systemic Sclerosis

Systemic sclerosis (SSc) is a multisystem connective tissue disease characterised by pathological processes involving autoimmunity, vasculopathy and resultant extensive skin and organ fibrosis. Recent studies have demonstrated activation and aberrant wound healing responses in the epithelial layer of the skin in this disease, implicating the epithelial keratinocytes as a source of pro-fibrotic and inflammatory mediators. In this paper, we investigated the role of Immunoglobulin G (IgG) autoantibodies directed against epithelial cells, as potential initiators and propagators of pathological keratocyte activation and the ensuing SSc fibrotic cascade. A keratinocyte cell-based ELISA is used to evaluate the binding of SSc IgG. SSc skin biopsies were stained by immunofluorescence for the presence of IgG in the keratinocyte layer. Moreover, IgG purified from SSc sera was evaluated for the potential to activate keratinocytes in tissue culture and to induce TLR2 and 3 signalling in reporter cell lines. We demonstrate enhanced binding of SSc IgG to keratinocytes and the activation of these cells leading to the release of IL-1α, representing a potential initiating pathway in this disease.

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.

Interference of B lymphocyte tolerance by prolactin in rheumatic autoimmune diseases

Systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and systemic sclerosis (SSc) are the most common rheumatic autoimmune diseases/disorders (RADs) that affect autologous connective tissues as a result of the breakdown of the self-tolerance mechanisms of the immune system. Prolactin, a glycoprotein hormone, has been known for its crucial role in the pathogenesis of these rheumatic autoimmune diseases. In addition to regulating lymphocyte proliferation and antibody synthesis, prolactin is also responsible for regulating cytokine production. Moreover, it contributes to the breakdown of central and peripheral tolerance mechanisms of B lymphocytes. Given the crucial role of prolactin in the pathogenesis of the mentioned RADs, prolactin may contribute to their pathogenesis by the breakdown of tolerance. In the present study, the key role of prolactin to the breakdown of B lymphocyte tolerance and its possible implication for the pathogenesis of these diseases is discussed. Current literature supports prolactin's role in the breakdown of B lymphocyte central and peripheral tolerance mechanisms, such apoptosis, receptor editing, and also anergy. Therefore, prolactin may contribute to the pathogenesis of RADs by the breakdown of B lymphocyte tolerance. However, more investigations, particularly in RA and SSc animal models, are required to precisely address the pathologic role of prolactin.

Umbilical-Cord-Derived Mesenchymal Stromal Cells Modulate 26 Out of 41 T Cell Subsets from Systemic Sclerosis Patients

Systemic sclerosis (SSc) is an immune-mediated disease wherein T cells are particularly implicated, presenting a poor prognosis and limited therapeutic options. Thus, mesenchymal-stem/stromal-cell (MSC)-based therapies can be of great benefit to SSc patients given their immunomodulatory, anti-fibrotic, and pro-angiogenic potential, which is associated with low toxicity. In this study, peripheral blood mononuclear cells from healthy individuals (HC, n = 6) and SSc patients (n = 9) were co-cultured with MSCs in order to assess how MSCs affected the activation and polarization of 58 different T cell subsets, including Th1, Th17, and Treg. It was found that MSCs downregulated the activation of 26 out of the 41 T cell subsets identified within CD4⁺, CD8⁺, CD4⁺CD8⁺, CD4^-CD8^-, and γδ T cells in SSc patients (HC: 29/42) and affected the polarization of 13 out of 58 T cell subsets in SSc patients (HC: 22/64). Interestingly, SSc patients displayed some T cell subsets with an increased activation status and MSCs were able to downregulate all of them. This study provides a wide-ranging perspective of how MSCs affect T cells, including minor subsets. The ability to inhibit the activation and modulate the polarization of several T cell subsets, including those implicated in SSc's pathogenesis, further supports the potential of MSC-based therapies to regulate T cells in a disease whose onset/development may be due to immune system's malfunction.

Clinical and serological correlation of systemic sclerosis in Moroccan patients

Objective

SSc is a CTD characterized by excessive fibrosis of the skin and internal organs, along with microvascular damage, and is often associated with typical autoantibodies. The aim of this study was to analyse the correlation between specific autoantibody profiles, clinical and paraclinical features in Moroccan patients with SSc.

Methods

We analysed the presence of specific autoantibodies in 46 SSc patients using IIF on HEp-2 cells and immunodot. We then correlated the types of autoantibodies with clinical and laboratory manifestations.

Results

Among our patients, 86.9% were females. The mean age of patients at diagnosis was 50.21 years, with an average delay to diagnosis of 5 years. The main clinical manifestations found were RP (89.2%), sclerodactyly (84.8%), proximal scleroderma (67.4%), gastrointestinal involvement (50%) and interstitial lung disease (30.4%). According to the specific autoantibody profile, 14 patients were anti-topo I positive (30.4%), 8 anti-RNP (68 kDa/A/C) positive (17.4%) and 6 anti-RNA polymerase III positive (13%). We found a significant association of anti-RNA polymerase III with sclerodactyly and pulmonary arterial hypertension (P < 0.05). We also found an association between anti-topo I and interstitial lung disease in 30.4% of patients. There was no significant association between the positivity for the autoantibodies and other diagnosed clinical manifestations.

Conclusion

Some clinical manifestations of SSc might be positively correlated with the presence of specific autoantibodies. Environmental factors, ethnicity and gene interaction might also influence this correlation.

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.

Autoantibodies and Clinical Correlations in Polish Systemic Sclerosis Patients: A Cross-Sectional Study

We evaluated the prevalence of systemic sclerosis (SSc)-related autoantibodies and their clinical significance and compared the sensitivity of two line immunoblot assays on a prospective study group of 96 Polish SSc patients (ACR-EULAR 2013 criteria) whose sera were assessed by indirect immunofluorescence (HEp-2 and monkey liver) and line immunoblot assays: ANA Profile 3 and Systemic Sclerosis Profile by EUROIMMUN (Lübeck, Germany). Organ involvement was evaluated according to the EUSTAR Minimal Essential Data Set. The following autoantibodies’ prevalence was found: Scl-70 (36%), Ro-52 (28%), CENP-B (22%), CENP-A (20%), PM-Scl-75 (20%), PM-Scl-100 (14%), fibrillarin (7%), Th/To (7%), RNA polymerase III 11 kDa (5%), RNA polymerase III 155 kDa (3%), PDGFR (3%), NOR-90 (2%), and Ku (1%). Significant associations between the autoantibodies’ presence and organ involvement were found: ATA (dcSSc > lcSSc, less prevalent muscle weakness), Ro-52 (gangrene, DLCO < 60), CENP-B and A (lcSSc > dcSSc, normal CK), CENP-B (rarer digital ulcers and joint contractures), PM-Scl-100 and 75 (PM/SSc overlap, CK increase, muscle weakness, muscle atrophy), PM-Scl-100 (dcSSc unlikely), PM-Scl-75 (lung fibrosis), fibrillarin (muscle atrophy, proteinuria, conduction blocks, palpitations), Th/To (proteinuria, arthritis, muscle weakness, and rarer esophageal symptoms), RNA Polymerase III 11 kDa (arterial hypertension, renal crisis), RNA polymerase III 155 kDa (renal crisis), and PDGFR (dcSSc, tendon friction rubs). Additionally, the Systemic Sclerosis Profile was significantly more sensitive in detecting SSc-related autoantibodies than ANA Profile 3 (p = 0.002). In conclusion, individual autoantibodies associated with specific characteristics of SSc.

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.

Clinical and Autoantibody Associations in Antinuclear Antibody-Positive Systemic Sclerosis Lacking Prototypic Autoantibodies

Background/Objectives:

The subset of ANA-positive patients with systemic sclerosis (SSc) who lack prototypic SSc-specific autoantibodies (centromere, topoisomerase, RNA polymerase III, “triple negative SSc”) is poorly characterized. We assessed clinical features and prevalence of additional autoantibodies in these patients.

Methods:

In this case series patients with ANA+ and triple negative SSc antibodies were identified from two independent SSc cohorts (n=280) and demographic and clinical data were obtained over two years. Sera were screened for ANA and autoantibodies were examined by immunoblots. Significance was assessed through Fisher’s exact test and Student’s T-test.

Results:

Forty ANA+ triple negative SSc patients (14% of the two SSc cohorts) were identified. Mean age was 53 ± 14.5 years, 53% had limited disease, average disease duration was 9 ± 9.7 years, and MRSS was 7.6 ± 6.8. 47.5% of the patients had digital ulcers, 60% had interstitial lung disease and 15% had pulmonary hypertension. The most common immunofluorescence patterns were speckled and mixed speckled/nucleolar. Of 29 autoantibodies tested, the most prevalent were Ro-52 (50%), Th/To (40%), MDA5 (35%), SAE1 (28%). Ro-52 was associated with ILD (RR 2.67, p<0.001) and elevated CK (RR 2.64, p<0.05), and PM-75 was associated with digital ulcers (RR 2.18, p<0.05).

Conclusions:

ANA+ triple negative SSc patients represent an understudied and heterogeneous population of patients with a high prevalence of Ro-52 antibodies, an enrichment for myositis specific antibodies, and increased risk of interstitial lung disease. These patients are seen relatively frequently and should be regularly assessed for evidence of myopathy and lung involvement.

Differential immune response to xenobiotic-modified self-molecule in simple and connective tissue disease-associated primary biliary cholangitis

BACKGROUND AND AIMS

Our previous studies demonstrated that 2-octynoic acid (2OA) might alter the conformational structure of the inner lipoic acid (LA) binding domain (ILD) in the E2 subunit of pyruvate dehydrogenase complex (PDC-E2), leading to the loss of immune tolerance in simple primary biliary cholangitis (S-PBC). Here, we further explore if this etiological mechanism also accounts for connective tissue disease-associated PBC (CTD-PBC).

METHODS

Intein-mediated protein ligation was used to prepare ILD, LA-ILD and 2OA-ILD, and their reactivity with serum samples from 124 S-PBC and 132 CTD-PBC patients was examined. The antibodies to LA, 2OA, LA-ILD and 2OA-ILD, the isotypes of antibodies to LA, 2OA and ILD, were comparatively detected between the two patient groups by enzyme-linked immunosorbent assay and immunoblotting.

RESULTS

Both the percentage and reactivity of antibody to 2OA in S-PBC were significantly higher than in CTD-PBC. Antibodies to 2OA and to LA between the two groups separately shared the same characteristics. Remarkably, coexistence of the antibodies to LA-ILD and to 2OA, and coexistence of the antibodies to LA and to 2OA in S-PBC were both significantly more frequent than in CTD-PBC, whereas the percentage of anti-LA antibody without anti-2OA antibody in S-PBC was markedly lower than in CTD-PBC. Moreover, the isotype of antibody to LA was predominantly IgG in CTD-PBC, whilst this isotype was mainly IgM in S-PBC.

CONCLUSION

Xenobiotic 2OA might play less important pathogenic role in CTD-PBC than in S-PBC, suggesting that different underlying mechanisms are involved in their immune intolerance to PDC-E2.

The mosaic of autoimmunity - Finally discussing in person. The 13th international congress on autoimmunity 2022 (AUTO13) Athens

While autoimmunity is a branch of medicine linked to every single organ system via direct and indirect pathways, meeting in person to discuss autoimmunity during the 13^th international congress on autoimmunity (AUTO13) with participants from all over the world had a very good reason. The mechanisms involved in autoimmune diseases are of extreme importance and in fact critical in understanding the course of diseases as well as selecting proper therapies. COVID-19 has served as a great example of how autoimmunity is deeply involved in the disease and directly correlated to severity, morbidity, and mortality. For instance, initially the term cytokine storm dominated, then COVID-19 was addressed as the new member of the hyperferritinemic syndrome, and also the use of immunosuppressants in patients with COVID-19 throughout the pandemic, all shed light on the fundamental role of autoimmunity. Unsurprisingly, SARS-CoV-2 was called the “autoimmune virus” during AUTO13. Subsequently, the correlation between autoimmunity and COVID-19 vaccines and post-COVID, all were discussed from different autoimmune aspects during the congress. In addition, updates on the mechanisms of diseases, autoantibodies, novel diagnostics and therapies in regard to autoimmune diseases such as antiphospholipid syndrome, systemic lupus erythematosus, systemic sclerosis and others, were discussed in dedicated sessions. Due to the magnificence of the topics discussed, we aimed to bring in our article hereby, the pearls of AUTO13 in terms of updates, new aspects of autoimmunity, and interesting findings. While more than 500 abstract were presented, concluding all the topics was not in reach, hence major findings were summarized.

Kidney Involvement in Systemic Sclerosis

Background: Systemic sclerosis is a chronic multisystem autoimmune disease, characterized by diffuse fibrosis and abnormalities of microcirculation and small arterioles in the skin, joints and visceral organs. Material and Methods: We searched for the relevant articles on systemic sclerosis and kidney involvement in systemic sclerosis in the NIH library of medicine, transplant, rheumatologic and nephrological journals. Results: Half of patients with systemic sclerosis have clinical evidence of kidney involvement. Scleroderma renal crisis represents the most specific and serious renal event associated with this condition. It is characterized by an abrupt onset of moderate to marked hypertension and kidney failure. Early and aggressive treatment is mandatory to prevent irreversible organ damage and death. The advent of ACE-inhibitors revolutionized the management of scleroderma renal crisis. However, the outcomes of this serious complication are still poor, and between 20 to 50% of patients progress to end stage renal disease. Conclusions: Scleroderma renal crisis still represents a serious and life-threatening event. Thus, further studies on its prevention and on new therapeutic strategies should be encouraged.

Autoantibodies versus Skin Fibrosis Extent in Systemic Sclerosis: A Case-Control Study of Inverted Phenotypes

Objective: to describe the prevalences, characteristics, and survivals of patients with anti-topoisomerase 1 antibodies (ATA) and limited cutaneous systemic sclerosis (lSSc) and anti-centromere antibodies (ACA) and diffuse cutaneous systemic sclerosis (dSSc). Methods: patients with ATA lSSc or with ACA dSSc were included in a case-control retrospective study. Results: In our cohort of scleroderma, the prevalence of ACA dSSc and ATA lSSc was 1.1% (12/1040) and 8.9% (93/1040), respectively. ACA dSSc patients had less interstitial lung disease (ILD) (5 (41.7) vs. 74 (79.6); p < 0.01), more cardiac involvement, and more muscle involvement (3 (25) vs. 4 (4.3); p = 0.03 and 4 (33.3) vs. 4 (7.5); p = 0.02,) than ATA dSSc patients. ATA lSSc patients had a higher modified Rodnan skin score than ACA lSSc patients (4 [2−7.5] vs. 2 [0−5]; p < 0.01) and less cardiac or muscle involvement than ATA dSSc patients (6 (6.5) vs. 19 (20.4%); p < 0.01 and 15 (16.1) vs. 54 (58.1); p < 0.0001, respectively). The cumulative 5-year survival rate was 71% in ACA dSSc patients, 95% in ATA lSSc patients, 84% in ACA lSSc patients, and 66% in ATA dSSc patients (p < 0.0001). Conclusion: ATA lSSc and ACA dSSc have specific characteristics when compared to ATA dSSc or ACA lSSc. ATA lSSc patients have more ILD than ACA lSSc patients, and ATA dSSc patients have the worst prognosis. Overall, inverted phenotypes show the value of a patient assessment combining antibody and skin subset and should be considered as a separate group.

The Effect of Anti-Scl-70 Antibody Determination Method on Its Predictive Significance for Interstitial Lung Disease Progression in Systemic Sclerosis

OBJECTIVE

The objective of this study was to assess the predictive significance of anti-Scl-70 (anti-topoisomerase I) antibodies, as determined by three different methods, for decline in forced vital capacity (FVC) within the first year of follow-up in patients with systemic sclerosis (SSc)-related interstitial lung disease (ILD).

METHODS

Patients in the Genetics Versus Environment in Scleroderma Outcome Study cohort who had ILD (verified by imaging) and available FVC% at enrollment, plus 12 to 18 months thereafter, were examined. All patients had a disease duration of 5 years or less at enrollment. The annualized percentage change in FVC% at 1 year follow-up was the outcome variable. Anti-Scl-70 antibodies were determined by passive immunodiffusion (ID) against calf thymus extract, chemiluminescent immunoassay (CIA), and line blot immunoassay (LIA).

RESULTS

Ninety-one patients with a mean disease duration of 2.36 years were included. Anti-Scl-70 antibodies by ID predicted a faster rate of FVC% decline (b = -0.06, P = 0.04). None of the other clinical or serological variables significantly predicted ILD progression. Interestingly, anti-Scl-70 antibodies as determined by CIA and LIA were not significant predictors of FVC decline (P = 0.26 and 0.64, respectively). The observed level of agreement between ID and LIA was moderate (κ = 0.568), whereas it was good between ID and CIA (κ = 0.66).

CONCLUSION

Anti-Scl-70 antibodies determined by ID predicted faster FVC decline in patients with SSc-related ILD. Notably, both CIA and LIA for the same antibody did not predict rate of FVC decline at their current cutoffs of positivity. The discrepancy observed between anti-Scl-70 antibody assays can have relevant implications for clinical care and trial enrichment strategies in SSc-ILD.

PDGF/PDGFR: A Possible Molecular Target in Scleroderma Fibrosis

Systemic sclerosis (SSc) is a clinically heterogeneous disorder of the connective tissue characterized by vascular alterations, immune/inflammatory manifestations, and organ fibrosis. SSc pathogenesis is complex and still poorly understood. Therefore, effective therapies are lacking and remain nonspecific and limited to disease symptoms. In the last few years, many molecular and cellular mediators of SSc fibrosis have been described, providing new potential options for targeted therapies. In this review: (i) we focused on the PDGF/PDGFR pathway as key signaling molecules in the development of tissue fibrosis; (ii) we highlighted the possible role of stimulatory anti-PDGFRα autoantibodies in the pathogenesis of SSc; (iii) we reported the most promising PDGF/PDGFR targeting therapies.

Autoantibody profiles associated with morbidity and mortality in scleroderma renal crisis

OBJECTIVE

To investigate the association of autoantibodies with scleroderma renal crisis (SRC) among Japanese patients.

METHODS

The clinical characteristics and mortality of 330 patients with systemic sclerosis (SSc) at Kyoto University Hospital were retrospectively analyzed, focusing on anti-topoisomerase I, anti-centromere, anti-RNA polymerase III (RNAPIII), and anti-U1-RNP. Logistic regression analyses were performed to examine the association of autoantibodies with the development and mortality of SRC.

RESULTS

SRC was observed in 24 out of 330 SSc patients, including anti-topoisomerase I (n = 12/24, 50%), anti-RNAPIII (n = 7/24, 29%), anti-U1-RNP (n = 5/24, 21%), and anti-centromere (n = 3/24, 13%). Anti-U1-RNP (odds ratio [95% confidence interval], 3.63 [1.11-10.2]), anti-topoisomerase I (3.22 [1.37-7.57]), and anti-RNAPIII (3.29 [1.16-8.70]) were associated with the development of SRC. Furthermore, anti-topoisomerase I (6.00 [1.11-41.1]) was associated with the 1-year mortality of SRC. The 1-year survival rate after the onset of SRC among all patients and those positive for anti-topoisomerase I was 54% and 33%, respectively. In contrast, the survival rate in patients negative for anti-topoisomerase I was 75%, of which the survival rate of patients positive for anti-RNAPIII and anti-centromere was 83% and 100%, respectively.

CONCLUSION

Specific SSc-related autoantibodies were associated with the morbidity and mortality of SRC.

Anti-Ro/SS-A Antibody is Associated with Worse Pulmonary Outcome and Reduced Overall Survival in Systemic Sclerosis

OBJECTIVE

We sought to determine the association of anti-Ro/SS-A antibody with organ involvement and disease outcome, in patients with systemic sclerosis (SSc).

METHODS

A retrospective, long-term study of a cohort of incident patients diagnosed with SSc, and continuously followed at our rheumatology clinic during 1990-2018.

RESULTS

Included were 105 patients with known anti-Ro/SS-A antibody status, 92.4% female, mean age at diagnosis 52.0±15.6 years, and median follow-up 10 years; 64% were diagnosed with limited cutaneous SSc, 18% with diffuse cutaneous SSc, and 18% had SSc siné scleroderma or undetermined disease type. Anti-Ro/SS-A antibody tested positive in 21% of patients. In univariate analysis, anti-Ro/SS-A antibody-positivity was significantly associated with SSc overlap with Sjogren's syndrome (p <0.001). Pulmonary function tests (PFT) deterioration at last encounter was significantly associated with anti-Ro/SS-A antibody-positivity. In multivariate regression for anti-Ro/SS-A antibody-positive SSc patients and disease outcome (adjusted for age>50 years, smoking, and baseline predicted forced vital capacity (pFVC) < 80%), positive anti-Ro/SS-A antibody was significantly associated with higher all-cause mortality rate (HR 5.17, CI 95% 1.18-22.67, p=0.029), and greater deterioration of pFVC defined as decrement of last available pFVC compared to first available pFVC of ≥10% (HR 3.65, CI 95% 1.07-12.38, p=0.038).

CONCLUSIONS

Anti-Ro/SS-A antibody is an independent risk factor for worse pulmonary outcome and higher all-cause mortality in patients with SSc, independent of SSc clinical and/or serological subtype.

Insights into origins and specificities of autoantibodies in systemic sclerosis

PURPOSE OF REVIEW

Autoantibodies are hallmark findings in systemic sclerosis (SSc), often present prior to disease onset. Clinical diagnosis and prognosis of SSc have long relied on the antitopoisomerase - anticentromere - anti-RNA polymerase antibody trichotomy. However, many more autoantibodies found in SSc are being actively investigated for insights into triggering events, mechanisms of tolerance break, and connections to tissue damage. This review examines recent studies on SSc autoantibodies and the early events that lead to their development.

RECENT FINDINGS

Recent work has elucidated potential connections between human cytomegalovirus infection, silicone breast implants, and malignancy to SSc autoantibody development. At the level of the dendritic cell:T cell interaction, where tolerance is broken, new studies identified shared motifs in the peptide-binding domains of SSc-associated human leukocyte antigen alleles. Immunological analysis of SSc patient B cells has uncovered several anomalies in the regulatory capacities of SSc naïve and memory B cell populations. Expanding efforts to uncover new SSc autoantibodies revealed anti-CXCL4, anticollagen V, and other autoantibodies as potential players in disease pathogenesis.

SUMMARY

Further research into the role of autoantibodies in SSc development may uncover new mechanism-guided therapeutic targets. In addition, a better understanding of autoantibody associations with SSc disease outcomes will improve clinical care.

Identification of potential autoantigens in anti-CCP-positive and anti-CCP-negative rheumatoid arthritis using citrulline-specific protein arrays

The presence or absence of autoantibodies against citrullinated proteins (ACPAs) distinguishes two main groups of rheumatoid arthritis (RA) patients with different etiologies, prognoses, disease severities, and, presumably, disease pathogenesis. The heterogeneous responses of RA patients to various biologics, even among ACPA-positive patients, emphasize the need for further stratification of the patients. We used high-density protein array technology for fingerprinting of ACPA reactivity. Identification of the proteome recognized by ACPAs may be a step to stratify RA patients according to immune reactivity. Pooled plasma samples from 10 anti-CCP-negative and 15 anti-CCP-positive RA patients were assessed for ACPA content using a modified protein microarray containing 1631 different natively folded proteins citrullinated in situ by protein arginine deiminases (PADs) 2 and PAD4. IgG antibodies from anti-CCP-positive RA plasma showed high-intensity binding to 87 proteins citrullinated by PAD2 and 99 proteins citrullinated by PAD4 without binding significantly to the corresponding native proteins. Curiously, the binding of IgG antibodies in anti-CCP-negative plasma was also enhanced by PAD2- and PAD4-mediated citrullination of 29 and 26 proteins, respectively. For only four proteins, significantly more ACPA binding occurred after citrullination with PAD2 compared to citrullination with PAD4, while the opposite was true for one protein. We demonstrate that PAD2 and PAD4 are equally efficient in generating citrullinated autoantigens recognized by ACPAs. Patterns of proteins recognized by ACPAs may serve as a future diagnostic tool for further subtyping of RA patients.

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

OBJECTIVE

Anti-NOR90 antibodies are usually found in patients with systemic sclerosis (SSc); however, their clinical relevance remains obscure. We developed an enzyme-linked immunosorbent assay (ELISA) for measuring them to investigate the clinical features of patients with anti-NOR90 antibodies.

METHODS

Serum samples from 1,252 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.

RESULTS

Five (0.4%) patients in the Nagoya University Hospital cohort had anti-NOR90 antibodies. One patient with diffuse cutaneous SSc, 3 with limited cutaneous SSc, and 1 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 4 anti-NOR90-positive SSc patients had interstitial lung disease (ILD), and 2 of those 4 had cancer. Three (1.2%) patients in the Tosei General Hospital cohort had anti-NOR90 antibodies. All 3 of the anti-NOR90-positive IIP patients had gastrointestinal tract involvement, and 2 of those 3 had cancer or skin lesions observed in SSc.

CONCLUSIONS

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.

Assessment of antinuclear antibodies (ANA): National recommendations on behalf of the Croatian society of medical biochemistry and laboratory medicine

Antinuclear antibodies (ANA) represent a family of autoantibodies targeting ubiquitous cellular constituents and are a hallmark of systemic inflammatory autoimmune rheumatic diseases named connective tissue diseases (CTD). The gold standard method for ANA determination is indirect immunofluorescence (IIF) on the human laryngeal epidermoid carcinoma cell line type 2 substrate (HEp-2), but with increasing demand for ANA testing, novel methods eased for automation emerged, which allows testing by staff less experienced in this specific field of laboratory diagnostic. In 2016 The working group (WG) for laboratory diagnostics of autoimmune diseases as part of the Committee for the Scientific Professional Development of the Croatian Society of Medical Biochemistry and Laboratory Medicine (CSMBLM) published the data of a survey regarding general practice in laboratory diagnostics of autoimmune diseases in Croatia. Results indicated high diversity in the performance of autoantibody testing as well as reporting of the results and indicated the need of creating recommendations for the assessment of ANA that would help harmonize diagnostics of systemic autoimmune rheumatic diseases in Croatia. This document encompasses twenty-seven recommendations for ANA testing created concerning indications for ANA testing, preanalytical, analytical, and postanalytical issues, including rational algorithm and quality control assurance. These recommendations are based on the relevant international recommendations and guidelines for the assessment of ANA testing and relevant literature search and should help to harmonize the approach in ANA testing and clarify differences in interpretation of the results obtained using different methods of determination.

Evaluation of a novel particle-based multi-analyte technology for the detection of anti-fibrillarin antibodies

Systemic sclerosis (SSc) is a heterogeneous autoimmune disease associated with several anti-nuclear antibodies (ANA), including those in the classification criteria (anti-centromere, anti-topoisomerase I (Scl-70), anti-RNA Pol III). However, the presence of less common antibodies such as anti-fibrillarin (U3-RNP) that generate a clumpy nucleolar pattern by HEp-2 indirect immunofluorescence assay (IFA, ICAP AC-9) are considered disease specific and are with clinical subsets of SSc, therefore playing a role in diagnosis and prognosis. A specific and sensitive anti-fibrillarin assay would be an important addition to serological diagnosis and evaluation of SSc. The goal of this study was to evaluate a new particle-based multi-analyte technology (PMAT) for the measurement of anti-fibrillarin antibodies. A total of 149 patient samples were collected including 47 samples from France (Lyon and Paris, n = 32) and Italy (Careggi Hospital, Florence, n = 15) selected based on AC-9 HEp-2 IFA staining (> 1:640, clumpy nucleolar pattern) and 102 non-SSc controls (inflammatory bowel disease (IBD) n = 20, Sjögren's syndrome (SjS) n = 20, infectious disease (ID) n = 7, systemic lupus erythematosus (SLE) n = 17, rheumatoid arthritis (RA) n = 17, and healthy individuals (HI) n = 21). All samples were tested on the anti-fibrillarin PMAT assay (research use only, Inova Diagnostics, USA). Additionally, the 47 anti-fibrillarin positive samples were also tested on PMAT assays for detecting other autoantibodies in ANA-associated rheumatic diseases (AARD). Anti-fibrillarin antibody data performed by fluorescence enzyme immunoassay (FEIA, Thermo Fisher, Germany) was available for 34 samples. The anti-fibrillarin PMAT assay was positive in 31/32 (96.9%, France) and 12/15 (80.0%, Italy) of samples preselected based on the AC-9 IIF pattern (difference p = 0.09). Collectively, the PMAT assay showed 91.5% (95% confidence interval (CI): 80.1-96.6%) sensitivity with 100.0% (95% CI: 96.4-100.0%) specificity in non-SSc controls. Strong agreement was found between PMAT and FEIA with 100.0% positive qualitative agreement (34/34) and quantitative agreement (Spearman's rho = 0.89, 95% CI: 0.77.9-0.95%, p < 0.0001). Although most anti-fibrillarin positive samples were mono-specific (69.8%), some expressed additional antibodies (namely Scl-70, centromere, dsDNA, Ro52, Ro60, SS-B, Ribo-P, DFS70, and EJ). In conclusion, this first study on anti-fibrillarin antibodies measured using a novel PMAT assay shows promising results where the new PMAT assay had high level of agreement to FEIA for the detection of anti-fibrillarin antibodies. The availability of novel AFA assays such as PMAT might facilitate the clinical deployment, additional studies, standardization efforts, and potentially consideration of AFA for next generations of the classification criteria.

Pharmacological Interventions for Pulmonary Involvement in Rheumatic Diseases

Among the diverse forms of lung involvement, interstitial lung disease (ILD) and pulmonary arterial hypertension (PAH) are two important conditions in patients with rheumatic diseases that are associated with significant morbidity and mortality. The management of ILD and PAH is challenging because the current treatment often provides only limited patient survival benefits. Such challenges derive from their common pathogenic mechanisms, where not only the inflammatory processes of immune cells but also the fibrotic and proliferative processes of nonimmune cells play critical roles in disease progression, making immunosuppressive therapy less effective. Recently, updated treatment strategies adopting targeted agents have been introduced with promising results in clinical trials for ILD ad PAH. This review discusses the epidemiologic features of ILD and PAH among patients with rheumatic diseases (rheumatoid arthritis, myositis, and systemic sclerosis) and the state-of-the-art treatment options, focusing on targeted agents including biologics, antifibrotic agents, and vasodilatory drugs.

Metabolic mediators determine the association of antinuclear antibody subtypes with specific clinical symptoms in systemic sclerosis

PURPOSE

The aim of this study was to investigate the possible link between different types of systemic sclerosis-specific antinuclear antibodies, adipokines and endothelial molecules which were recently found to have a pathogenic significance in systemic sclerosis.

MATERIALS/METHODS

Serum concentration of adiponectin, resistin, leptin, endothelin-1, fractalkine and galectin-3 were determined in the sera of patients with systemic sclerosis (n ​= ​100) and healthy controls (n ​= ​20) using ELISA.

RESULTS

The following associations between antinuclear antibodies and increased serum concentrations were identified: anticentromere antibodies with endothelin-1 (p ​< ​0.0001; mean level in patients 2.21 vs control group 1.31 ​pg/ml), anti-topoisomerase I antibodies with fractalkine (p ​< ​0.0001; 3.68 vs 1.68 ​ng/ml) and galectin-3 (p ​= ​0.0010, 6.39 vs 3.26 ​ng/ml). Anti-RNA polymerase III antibodies were associated with increased resistin (p ​< ​0.0001; 15.13 vs 8.54 ​ng/ml) and decreased adiponectin (p ​< ​0.0001; 2894 vs 8847 ​ng/ml).

CONCLUSION

In systemic sclerosis metabolic and vascular factors may serve as mediators between immunological abnormalities and non-immune driven clinical symptoms.

The clinical and laboratory features associated with cancer in patients with primary biliary cholangitis: a longitudinal survey-based study

OBJECTIVES

To analyze the clinical and laboratory features of primary biliary cholangitis (PBC) patients complicated with cancer, and explore the potential factors associated with cancer.

METHODS

We consecutively enrolled PBC patients from January 2002 to February 2016 in Peking Union Medical College Hospital and performed a structured interview, systemic rheumatologic evaluation, and laboratory tests. The risk factors associated with cancer were analyzed with univariate and multivariable logistic regression and proportional hazard model.

RESULTS

Among the 580 PBC patients enrolled, 51 cancers were identified in 51 patients (8.8%), including 45 (88.2%) solid tumors and 6 (11.8%) hematologic malignancies. Patients with cancer were older (62.1 ± 9.6 vs. 55.4 ± 11.6 years, p < 0.01) than patients without cancer. Additionally, positive anti-centromere antibody (ACA) was more frequently observed in patients without cancer (25.9% vs 4.3%, p = 0.019) compared with patients with cancer diagnosed after establishing PBC. The median follow-up after the diagnosis of PBC was 4 years (IQR 2.0-6.6). Furthermore, multivariable logistic regression confirmed that older age was associated with cancer in PBC patients (odds ratio (OR) = 1.045, 95% confidence interval (CI): 1.006-1.085), and positive ACA was a protective factor (OR = 0.116, 95% CI: 0.015-0.876). Additionally, proportional hazard model analysis revealed that age was a risk factor (hazard ratio = 1.045, 95% CI: 1.012-1.080), and positive ACA was a protective factor (hazard ratio = 0.232, 95% CI: 0.055-0.977) for cancer.

CONCLUSIONS

Both solid tumor and hematologic malignancy were prevalent in PBC patients. Older age was associated with cancer, and positive ACA was a protective factor of cancer in PBC patients. Key Points • Patients with PBC could present with both solid tumors and hematologic malignancies. • Multivariable logistic regression and proportional hazard model analysis revealed that age was a risk factor as we know, and positive ACA was a protective factor.

Scleroderma-specific autoantibodies embedded in immune complexes mediate endothelial damage: an early event in the pathogenesis of systemic sclerosis

BACKGROUND

Consistently with their diagnostic and prognostic value, autoantibodies specific for systemic sclerosis (SSc) embedded in immune complexes (ICs) elicited a pro-inflammatory and pro-fibrotic cascade in healthy skin fibroblasts, engaging Toll-like receptors (TLRs) via their nucleic acid components. The objective of this study was to investigate the pathogenicity of SSc-ICs in endothelial cells.

METHODS

ICs were purified from the sera of SSc patients bearing different autoantibody specificities (antibodies against DNA topoisomerase I, centromeric proteins, RNA polymerase, and Th/To), patients with systemic lupus erythematosus (SLE) and primary anti-phospholipid syndrome (PAPS), or healthy controls (NHS) using polyethylene glycol precipitation. Human umbilical vein endothelial cells (HUVECs) were incubated with ICs, positive and negative controls. mRNA levels of endothelin-1 (et-1), collagenIα1 (colIα1), interferon (IFN)-α, and IFN-β were investigated by real-time PCR; et-1 and il-6 mRNA levels were assessed after pre-treatment with bafilomycin. ICAM-1 expression was evaluated by cell ELISA; secretion of IL-6, IL-8, and transforming growth factor (TGF)-β1 in culture supernatants was measured by ELISA. The expression of Fcγ receptors (CD64, CD32, and CD16) was assessed in endothelial cells at FACS analysis. Intracellular signaling pathways culminating with NFκB, p38MAPK, SAPK-JNK, and Akt were assessed by Western blotting. Healthy skin fibroblasts were stimulated with supernatants from HUVECs incubated with ICs, and TGF-β1 secretion and mRNA levels of colIα1 and matrix metalloproteinase (mmp)-1, protein expression of α smooth muscle actin (α-SMA), and IL-6 were evaluated by Western blotting; et-1 mRNA levels were assessed in fibroblasts pre-treated with IL-6 and TGF-β inhibitors and stimulated with ATA-ICs.

RESULTS

All SSc stimulated IL-6 secretion; ACA-ICs and anti-Th/To-ICs increased ICAM-1 expression; all SSc-ICs but anti-Th/To-ICs augmented IL-8 levels; all SSc-ICs but ACA-ICs and ARA-ICs upregulated et-1, and all SSc-ICs but ARA-ICs affected TGF-β1 secretion. colIα1, IFN-α, and IFN-β mRNA levels were not affected by any SSc-IC. FcγRII (CD32) and FcγRIII (CD16) were not detectable on HUVECs, while FcγRI (CD64) was minimally expressed. A differential modulation of tlr expression was observed: tlr2, tlr3, and tlr4 were upregulated by ATA-ICs and ACA-ICs, while anti-Th/To-ICs resulted in tlr9 upregulation. Pre-treatment with bafilomycin did not affect the upregulation of et-1 and il-6 induced by ATA-ICs, ACA-ICs, and anti-Th/To-ICs; a 23% reduction in both genes was reported for ARA-ICs. All SSc-ICs activated p38MAPK and Akt, and all SSc-ICs but ARA-ICs yielded the activation of NFκB; ATA-ICs and ACA-ICs increased the activation rate of both subunits of SAPK-JNK. When healthy skin fibroblasts were stimulated with supernatants from HUVECs incubated with SSc-ICs, TGF-β1 secretion, colIα1, α-SMA, and IL-6 expression levels were significantly modulated. Pre-treatment with IL-6 and TGF-β inhibitors prevented et-1 upregulation induced by ATA-ICs by 85% and 77%, respectively.

CONCLUSIONS

These data provide the first demonstration of the pathogenicity of ICs from scleroderma patients with different autoantibodies on the endothelium. Endothelial activation induced by SSc-ICs ultimately led to a pro-fibrotic phenotype in healthy skin fibroblasts.

Antinuclear Antibodies in Systemic Sclerosis: an Update

Systemic sclerosis is an autoimmune disease characterized by fibrosis of skin and internal organs, vasculopathy, and dysregulation of immune system. A diagnostically important feature of immunological abnormalities in systemic sclerosis is the presence of circulating antinuclear antibodies, which may be detected in 90-95% of patients with either of the four main laboratory methods: immunofluorescence, enzyme-linked immunosorbent assay, immunodiffusion, and immunoblotting. There are several antinuclear antibodies specific for systemic sclerosis. These include antibodies against topoisomerase (anti-TOPO I), kinetochore proteins (ACA), RNA polymerase enzyme (anti-RNAP III), ribonuclear proteins (anti-U11/U12 RNP, anti-U1 RNP, anti-U3 RNP) and nucleolar antigens (anti-Th/To, anti-NOR 90, anti-Ku, antiRuvBL1/2, and anti-PM/Scl). Autoantibodies specific for systemic sclerosis have been linked to distinct clinical features. Therefore, detecting a particular antibody type is important in predicting a possible organ involvement and prognosis and may have an impact on monitoring and treatment.

Prevalence and clinical characteristics of earlobe crease in systemic sclerosis: Possible association with vascular dysfunction

Patients with systemic sclerosis (SSc) develop various vasculopathy-induced vascular disorders such as Raynaud's phenomenon, abnormal nail-fold capillaries, persistent digital ischemia, digital ulcers (DU), and sometimes develop renal crisis and pulmonary artery hypertension (PAH), affecting prognosis. Earlobe crease (ELC), also known as Frank's sign, is a wrinkle extending from the tragus to the outer border of the earlobe and is generally recognized as the sign of cardiovascular events. However, no previous study analyzed the association between ELC and SSc. In this study, we examined the prevalence and clinical characteristics of ELC in SSc patients. We analyzed 145 Japanese SSc patients and found that the prevalence of ELC in SSc patients was 23.4% (43/145), similar to that previously reported in the general population without SSc. Using univariate analysis, we found that SSc patients with ELC were characterized by old age, high incidence of DU, ILD and PAH, and high complication of coronary artery diseases (CAD) compared with SSc patients without ELC. In multivariate analysis, ELC was significantly associated with old age and incidence of DU. PAH tended to correlate with ELC without statistical significance. These results suggest that ELC may be associated with vascular disorders in SSc patients. This is the first report concerning the prevalence and clinical characteristics of ELC in patients with SSc. ELC is very easy to detect in clinical practice and helps physicians to identify SSc patients at risk of developing vascular disorders such as DU and PAH.

Performance evaluation of a commercial line blot assay system for detection of myositis- and systemic sclerosis-related autoantibodies

INTRODUCTION/OBJECTIVES

A line blot (LB) assay is a multi-analyte platform capable of simultaneously detecting multiple anti-nuclear antibody specificities. Here, we evaluated the performance of a commercial LB assay developed for the identification of myositis- or systemic sclerosis (SSc)-related autoantibodies (autoAbs).

METHOD

We screened 300 serum samples from patients with various connective tissue diseases using an LB assay and compared the results of myositis- or SSc-related autoAbs with those identified by RNA and protein immunoprecipitation (IP) assays or indirect immunofluorescence (IIF).

RESULTS

The IP assays revealed anti-Jo-1 Abs in 14 patients, anti-EJ Abs in 12, anti-PL-7 Abs in 8, anti-PL-12 Abs in 4, anti-Mi-2 Abs in 6, anti-SRP Abs in 8, anti-topoisomerase I Abs in 54, anti-RNA polymerase III Abs in 24, anti-U3 RNP Abs in 9, anti-Th/To Abs in 9, anti-Ku Abs in 14 and anti-hUBF Abs in 4, whereas IIF identified anti-centromere in 35. Good agreement between the IP assays and the LB assay was found only for anti-Jo-1 and anti-centromere antibodies. When a cut-off was adjusted to reconcile with the results of IP assays, the detection performance of LB assay was improved for anti-EJ, anti-PL-7, anti-PL-12, anti-SRP, anti-topoisomerase I and anti-RNA polymerase III Abs. However, the results of anti-Mi-2, anti-U3 RNP, anti-Th/To, anti-hUBF and anti-Ku Abs remained discordant between the LB assay and IP assays at all cut-off levels.

CONCLUSIONS

Detection of myositis- or SSc-related autoAbs using a commercial LB assay requires great caution since it can yield analytically false-positive or false-negative results. Key Points • A line blot (LB) assay is a multi-analyte platform capable of simultaneously detecting multiple antibodies with anti-nuclear specificities. • Detection of myositis- or systemic sclerosis-related autoantibodies using a commercial LB assay requires great caution since it can yield analytically false-positive or false-negative results.

Successful Treatment of Pulmonary Arterial Hypertension in Systemic Sclerosis with Anticentriole Antibody

Systemic sclerosis (SSc) is characterized by skin sclerosis and multiple organ damages which may cause mortality and is usually accompanied with several specific autoantibodies, each of which is associated with characteristic complications. Among them, anticentriole antibody is recently reported to be highly associated with SSc-associated pulmonary arterial hypertension (SSc-PAH). In general, several vasodilators are used as therapeutic drugs for SSc-PAH, whereas immunosuppressive therapies are not. Here, we report the case of a 62-year-old female with anticentriole antibody-positive SSc-PAH treated with immunosuppressants and vasodilators. She presented with two-year exertional dyspnea and was diagnosed with PAH and SSc owing to the centriole staining pattern and other symptoms without digital sclerosis. Oral vasodilators were initially administered but were not sufficiently effective on dyspnea. Immunosuppressants such as prednisolone and cyclophosphamide were started. Both of them improved mean pulmonary arterial pressure and 6-minute walk distance, and the anticentriole antibody also disappeared. In this case, SSc-PAH with anticentriole antibody was properly diagnosed and immunosuppressants and vasodilators improved the hemodynamics of PAH with anticentriole antibody and stably maintained it and, in addition, reduced the titer of anticentriole antibody. This indicates that anticentriole antibody might represent a good responsive group to therapies among subgroups of patients with SSc-PAH.

Characteristics of Systemic Sclerosis patients with positive anti-Th/To antibodies: About 6 patients and literature review

Among the antibodies described in Systemic Sclerosis (SSc), anti-Th/To antibodies (anti-Th/To) are rare and have been poorly studied. Thus, little is known about the profile of anti-Th/To positive patients. From our local Biobank (Marseille, France), we retrospectively selected data for 6 patients positive for anti-Th/To with an Immunodot assay. All of them suffered from SSc, sharing clinical and biological common features such as a limited cutaneous form of SSc, a decreased lung diffusing capacity and a speckled nuclear nucleolar immunofluorescence pattern of antinuclear antibodies screening on HEp-2 cells. In order to further characterize patients positive for anti-Th/To, we performed a thorough literature review. From 402 studied patients positive for anti-Th/To, we confirmed that these antibodies are associated with the limited cutaneous form of the disease (88% of the patients), and with an SSc related-pulmonary involvement (50%). The review analysis pointed out the rarity of the anti-Th/To with an estimated mean frequency of 3.4% of all SSc patients worldwide, their usual exclusivity with respect to the specific antibodies of scleroderma, and their high specificity (around 98%) for the diagnosis of SSc.

Proteomics characterization of CENP-B epitope in Moroccan scleroderma patients with anti-centromere autoantibodies

BACKGROUND

Anti-centromere auto-antibodies (ACA) have been described as a marker in Systemic sclerosis (SSc) disease. CENP-B is the major centromere auto-antigen recognized by SSc patients with positive ACA. Our aim was to characterize the major epitope involved in the anti-CENP-B immune response of Moroccan SSc patients.

PATIENTS AND METHOD

For identification of SSc biomarkers, 80 sera from patients with SSc and systemic lupus erythematosus (SLE) were screened by indirect immunofluorescence test (IIF) to assess the presence of ANA reactivity. Immunoblotting analysis was performed for 11 sera with positive ACA using the N-terminal and C-terminal region of CENP-B protein as antigens.

RESULTS

29 out of 30 (96, 66 %) patients with SSc had positive ANA. 11 out of 30 (36, 67 %) patients were ACA positive and 6 of them produced auto-antibodies against Nt-CENPB antigen. Two of these 6 Nt-CENPB positive sera produced also other auto-antibodies associated to primary biliary cirrhosis. None of all sera tested showed reactivity against Ct-CENPB.

CONCLUSION

Our data showed, for the first time in Morocco, that the Nt-CENPB contains a major epitope for Moroccan SSc patients. These findings could provide additional information that would contribute to improving the diagnosis and management of these patients.

[Treatment of systemic sclerosis-associated interstitial lung disease]

BACKGROUND

Systemic sclerosis (SSc) is a fibrosing autoimmune disease of the connective tissue. In addition to skin fibrosis, pulmonary involvement and interstitial lung disease (ILD) in particular are the most common and severe manifestations of SSc. The disease is associated with a substantial risk of morbidity and mortality, especially in progressive ILD. In the last 5 years new treatment concepts for SSc-ILD have been investigated in numerous clinical studies.

MATERIAL AND METHODS

This review is based on a literature search in PubMed, focusing on the most relevant papers published up to the end of 2018 with the keywords "SSc" and "treatment".

RESULTS

The treatment of SSc-ILD has changed over the last few years due to the results of many clinical studies. The updated guidelines of the European League Against Rheumatism (EULAR) recommend the use of cyclophosphamide or hematopoietic stem cell transplantation. Data for a positive influence on SSc-ILD are also available for mycophenolate, tocilizumab and anabasum. Because of the pathophysiological similarities to idiopathic pulmonary fibrosis, the use of the antifibrotic agents nintedanib and pirfenidone is currently being investigated in randomized, multicenter clinical trials and could be a novel and promising therapeutic strategy.

CONCLUSION

Current drug studies may provide innovative therapeutic perspectives for SSc-ILD and could significantly improve the prognosis of affected patients in the future.

Systemic Sclerosis Associated Interstitial Lung Disease: New Directions in Disease Management

A subgroup of patients with systemic sclerosis (SSc) develop interstitial lung disease (ILD), characterized by inflammation and progressive scarring of the lungs that can lead to respiratory failure. Although ILD remains the major cause of death in these individuals, there is no consensus statement regarding the classification and characterization of SSc-related ILD (SSc-ILD). Recent clinical trials address the treatment of SSc-ILD and the results may lead to new disease-altering therapies. In this review, we provide an update to the diagnosis, management and treatment of SSc-ILD.

Renal pathology and clinical associations in systemic sclerosis: a historical cohort study

Background

The information guiding the treatment decision(s) for renal diseases in systemic sclerosis (SSc) is the renal pathological finding. This study aimed to evaluate the renal pathological diagnosis and its clinical feature among SSc.

Method

A historical cohort study was performed on adult Thai SSc patients who underwent renal biopsy during January 2005-December 2016. The renal pathologic findings and patient clinical characteristics were reviewed. Chi-square or Fisher's exact test was applied to analyze the association between clinical manifestation and renal pathology.

Results

Of the 26 SSc patients identified (77% female), 46% had the diffuse cutaneous SSc subtype. The mean age at the time of biopsy was 53.2±14.4 years and median duration of disease was 2.4 years (IQR 0.5-7.0). Rapidly progressive glomerulonephritis (RPGN) was the most common renal manifestation (53.9%) followed by nephrotic syndrome (19.2%) and nephritis (11.5%). The pathological diagnosis included lupus nephritis (LN) class IV (26.9%), LN class V (19.2%), scleroderma renal crisis (SRC; 19.3%), progressive renal disease in scleroderma (7.7%), and IgA nephropathy (7.7%). The nephrotic syndrome was the most common renal feature among LN class V patients, whereas RPGN was the commonest renal presentation among LN class IV and SRC patients (p=0.001). Dialysis treatment at the time of kidney biopsy was significantly higher in SRC patients than in the other groups (p<0.001). The SRC tended to have more frequent cardiac involvement, pulmonary fibrosis, and shorter disease duration than the other groups.

Conclusion

This is the first report of renal pathologic findings in Thai SSc patients. RPGN is the commonest renal manifestation among SSc who underwent kidney biopsy; for whom LN was the most common pathological finding. Nephrotic syndrome is a clinical feature of glomerular diseases other than renal involvement in SSc.

[Cancers in systemic sclerosis : risk factors, impact on survival and literature review]

INTRODUCTION

Patients with systemic sclerosis (SSc) have an increased risk of malignancy. In this study, we aimed to analyze the prevalence of cancer, the risk factors and the impact on overall survival.

PATIENTS AND METHODS

We analyzed clinical (history of cancer, toxic exposition, organ involvement), immunological and treatment data in a monocentric cohort of SSc patients followed between January 2004 and December 2017.

RESULTS

Two hundred and ten patients with SSc were included. During the follow-up, twenty-one patients (10 %) were diagnosed with malignancies. The underlying malignancies were breast adenocarcinoma (n=6, 28%), lung cancer (n=6, 28%), colorectal (colic adenocarcinoma, carcinoid tumor of the appendix), ovarian and cervix uteri, melanoma, kidney and papillary thyroid carcinoma (one of each). The median time between the first visit and the diagnosis of cancer was 4 [2-10] years. The overall survival in SSc patients with cancer was not significantly different from patients without cancer, with median survival during the first quartile (75%) at 12 years for patients with cancer and 11.6 years for those without cancer (P=0.9). The history of renal scleroderma crisis (HR 10.99, IC95% [1.95-62.07]; P=0.006) and the presence of anti-topoisomerase I antibodies (HR 5.5, IC95% [1.40-21.67]; P=0.01) were associated with an increased risk of cancer, whereas the presence of gastroesophageal reflux was inversely associated with the cancer occurrence (HR 0.22, IC95% [0.056-0.867]; P=0.03).

CONCLUSION

The history of renal scleroderma crisis and the positivity of anti-topoisomerase I antibodies were associated with an increased risk of cancer in SSc patients in this monocentric study.

Skin thickness score as a surrogate marker of organ involvements in systemic sclerosis: a retrospective observational study

Background

Previous studies have shown the relationship between higher skin thickness score and the existence of organ involvements in systemic sclerosis (SSc). Here, we firstly investigated the correlation between skin thickness score and quantitative measurements of each organ involvement in Japanese patients with SSc.

Methods

All Japanese SSc patients hospitalized to our clinic for initial evaluation of SSc were selected. Skin thickness was evaluated by modified Rodnan total skin thickness score (mRSS). Relationship between mRSS and prevalence or incidence of organ involvements was examined by logistic analyses. Correlation between mRSS and quantitative measurements of organ involvements was examined by correlation analyses and regression analyses.

Results

We recruited 198 patients into our study. The mean disease duration was 7.3 years with the mean follow-up duration of 3.2 years. Multivariate logistic regression analyses revealed that higher mRSS is related to higher prevalence of interstitial lung disease (P < 0.05), restrictive impairment (P < 0.01), and diffusion impairment (P < 0.05) of the lung. Correlation analyses revealed mRSS negatively correlates with forced vital capacity (P < 0.001) and diffusing capacity (P < 0.001) of the lung. Correlation between longitudinal change of mRSS and that of forced vital capacity (P < 0.05) or diffusing capacity (P < 0.001) of the lung was also demonstrated.

Conclusions

Skin thickness score significantly correlates with quantitative measurements of lung involvement in Japanese patients with SSc.

Demographic and clinical characteristics of spinal calcinosis in systemic sclerosis: Possible association with peripheral angiopathy

The objective was to evaluate the demographic and clinical characteristics of systemic sclerosis (SSc) patients with spinal calcinosis. Paraspinal and intraspinal calcinosis was assessed blindly by orthopedic surgeons specializing in spinal diseases using chest high-resolution computed tomography (CT) that was performed for the screening and prospecting of interstitial lung disease in 159 Japanese SSc patients. Among these patients, we identified 27 (17%) with spinal calcinosis, and the most common site was cervical level at 77.8% (21/27). The frequency of spinal calcinosis in the late stage was higher than in the early stage (44.4% vs 29.6%). Multiple calcinosis was identified in 18.5% (5/27). The frequency of paraspinal calcinosis only was 59.3%, intraspinal calcinosis only 18.5%, and both intraspinal and paraspinal calcinosis 22.2%. Among SSc patients, 4.4% (7/159) had CT-based evidence of spinal cord compression. Among cases with spinal cord compression, only one had neurological symptoms, and surgical removal improved the symptoms. The other six SSc patients with spinal calcinosis (3.8% of 159) had no symptoms. Male sex (29.6%) and severe peripheral vasculopathy such as digital ulcers (55.6%) and acro-osteolysis (33.3%) were significantly more frequent in the SSc patients with spinal calcinosis than in the SSc patients without spinal calcinosis (10.6%, 32.6% and 14.4%, respectively). Our results suggest that severe peripheral vasculopathy may be associated with the development of spinal calcinosis. Because SSc patients are prone to spinal calcinosis, when SSc patients claim symptoms such as pain, numbness and movement disorder of the extremities, spinal calcinosis is a complication that should be taken into consideration.