The clinical relevance of autoantibodies in scleroderma

Autoantibodies in systemic sclerosis overlap syndrome and their correlation with organ damage and survival

BACKGROUND

Systemic sclerosis (SSc) often overlaps with other autoimmune diseases. More complex autoantibody profiles may be observed in SSc overlap syndrome (SSc OS). To determine the clinical significance of autoantibodies in SSc OS and classify the patients more accurately for better disease assessments, we analysed the correlation between serological profiles, organ involvements and outcomes.

METHODS

A retrospective cohort study was conducted in Peking University People's Hospital. Chi-square tests and analysis of variance were used to analyse univariate comparisons of clinical symptoms, organ involvement and laboratory indicators. Survival was evaluated using Cox proportional hazards model.

RESULTS

Among 141 cases, anti-Ro-52 was the most common antibody, followed by anti-centromere antibody and anti-Scl-70 antibody. We analysed the correlation between autoantibodies and vital organ damage in SSc OS patients, and compared the differences across four SSc OS subgroups (SSc SLE, SSc RA, SSc PM/DM and SSc SS) to demonstrate the correlation between autoantibodies and clinical characteristics and organ damage. Cox regression analysis showed that scleroderma renal crisis (SRC) (p = .004) and pulmonary arterial hypertension (PH) (p = .010) were independent risk factors for survival.

CONCLUSIONS

Autoantibodies are associated with clinical features, organ involvement and prognosis in SSc OS patients. Anti-Scl-70 antibody is associated with interstitial lung disease (ILD) and SRC, while ACA is a protective factor of ILD. SRC and PH are risk factors associated with death.

Biomarkers reflecting the pathogenesis, clinical manifestations, and guide therapeutic approach in systemic sclerosis: a narrative review

Systemic sclerosis (SSc) is a progressive autoimmune disorder that mainly affects the skin. There are other clinical manifestations as renal, pulmonary, cardiovascular, and gastrointestinal tract involvements. Based on the skin involvement there are two subtypes of SSc, as limited cutaneous SSc (lSSc) which involves the acral part of the body and diffuse cutaneous SSc (dSSc) resulting in significant skin thickening of the body. Despite of the extensive research the pathomechanism is not fully clarified, how Ssc develops, moreover identifying biomarkers to predict the clinical outcome and prognosis still remains challenging. Circulating biomarkers can be crucial to define the diagnosis, to predict the prognosis and monitor the clinical course. However, only some patients are responsive to the therapy in SSc, and there is a need to reach the ideal therapy for any individual to prevent or slow down the progression in early stages of the disease. In this narrative review, our purpose was to summarize the potential biomarkers in Ssc, describe their role in the diagnosis, pathomechanism, clinical course, organ manifestations, as well as the response to the therapy. Biomarkers assessment aids in the evaluation of disease progression, and disease outcome.

Assessing disease activity in scleroderma-related interstitial lung disease: a review and practical guide to management

Systemic sclerosis (SSc) is a heterogeneous disease with a propensity to involve multiple organ systems. There is a significant proportion of these patients with interstitial lung disease (ILD) who are at risk of mortality and morbidity. There are limited available tools to assess the severity of parenchymal lung involvement and are subject to confounding factors, including the presence of pulmonary hypertension and concomitant smoking history. The diagnostic tools include careful clinical history, examination, thoracic imaging, and pulmonary function tests. One of the limitations of assessing disease severity in SSc-ILD is the lack of standardized definitions for disease activity and serum biomarkers to predict future progression. Although there has been significant progress in managing SSc-related ILD over the last couple of decades with a few randomized double-blind clinical trials assessing the role of immunosuppression (mainly Cyclophosphamide and Mycophenolate Mofetil), the efficacy of these therapies is at best modest and is associated with significant toxicities. Furthermore, Nintedanib has shown promise in reducing forced vital capacity decline in SSc-ILD and in progressive fibrotic-ILD of a range of etiologies. Data are emerging for therapies like Rituximab and Tocilizumab, and we are likely to see further evidence of similar drugs being efficacious in this disease cohort. A relatively simplified algorithm is proposed in this review to guide clinicians dealing with ILD and SSc. It is imperative that clinicians take a multi-disciplinary approach to managing this complex disease in a changing therapeutic landscape.

T cells promote distinct transcriptional programs of cutaneous inflammatory disease in human skin structural cells

T cells and structural cells coordinate appropriate inflammatory responses and restoration of barrier integrity following insult. Dysfunctional T cell activity precipitates tissue pathology that occurs alongside disease-associated alterations of structural cell subsets, but the mechanisms by which T cells promote these changes remain unclear. We show that subsets of circulating and skin-resident CD4+ T cells promote distinct transcriptional outcomes in human keratinocytes and dermal fibroblasts that correspond with divergent T cell cytokine production. Using these transcriptional signatures, we identify T cell-dependent outcomes associated with inflammatory skin disease, including a set of Th17 cell-induced genes in keratinocytes that are enriched in the skin during psoriasis and normalized by anti-IL-17 therapy, and a skin-resident T cell-induced gene module enriched in scleroderma-associated fibroblasts. Interrogating clinical data using T cell-derived structural cell gene networks enables investigation of the immune-dependent contribution to inflammatory disease and the heterogeneous patient response to biologic therapy.

Imaging of Pulmonary Manifestations of Connective Tissue Disease

The majority of connective tissue diseases (CTDs) are multisystem disorders that are often heterogeneous in their presentation and do not have a single laboratory, histologic, or radiologic feature that is defined as the gold standard to support a specific diagnosis. Given this challenging situation, the diagnosis of CTD is a process that requires the synthesis of multidisciplinary data which may include patient clinical symptoms, serologic evaluation, laboratory testing, and imaging. Pulmonary manifestations of connective tissue disease include interstitial lung disease as well as multicompartmental manifestations. These CT imaging patterns and features of specific diseases will be discussed in this article.

Biomarkers in the Pathogenesis, Diagnosis, and Treatment of Systemic Sclerosis

Systemic sclerosis (SSc) is a complex autoimmune disease characterized by vascular damage, vasoinstability, and decreased perfusion with ischemia, inflammation, and exuberant fibrosis of the skin and internal organs. Biomarkers are analytic indicators of the biological and disease processes within an individual that can be accurately and reproducibly measured. The field of biomarkers in SSc is complex as recent studies have implicated at least 240 pathways and dysregulated proteins in SSc pathogenesis. Anti-nuclear antibodies (ANA) are classical biomarkers with well-described clinical classifications and are present in more than 90% of SSc patients and include anti-centromere, anti-Th/To, anti-RNA polymerase III, and anti-topoisomerase I antibodies. Transforming growth factor-β (TGF-β) is central to the fibrotic process of SSc and is intimately intertwined with other biomarkers. Tyrosine kinases, interferon-1 signaling, IL-6 signaling, endogenous thrombin, peroxisome proliferator-activated receptors (PPARs), lysophosphatidic acid receptors, and amino acid metabolites are new biomarkers with the potential for developing new therapeutic agents. Other biomarkers implicated in SSc-ILD include signal transducer and activator of transcription 4 (STAT4), CD226 (DNAX accessory molecule 1), interferon regulatory factor 5 (IRF5), interleukin-1 receptor-associated kinase-1 (IRAK1), connective tissue growth factor (CTGF), pyrin domain containing 1 (NLRP1), T-cell surface glycoprotein zeta chain (CD3ζ) or CD247, the NLR family, SP-D (surfactant protein), KL-6, leucine-rich α2-glycoprotein-1 (LRG1), CCL19, genetic factors including DRB1 alleles, the interleukins (IL-1, IL-4, IL-6, IL-8, IL-10 IL-13, IL-16, IL-17, IL-18, IL-22, IL-32, and IL-35), the chemokines CCL (2,3,5,13,20,21,23), CXC (8,9,10,11,16), CX3CL1 (fractalkine), and GDF15. Adiponectin (an indicator of PPAR activation) and maresin 1 are reduced in SSc patients. A new trend has been the use of biomarker panels with combined complex multifactor analysis, machine learning, and artificial intelligence to determine disease activity and response to therapy. The present review is an update of the various biomarker molecules, pathways, and receptors involved in the pathology of SSc.

Identification of Anti-SNRPA as a Novel Serological Biomarker for Systemic Sclerosis Diagnosis

Systemic sclerosis (SSc) is a systemic autoimmune disorder that leads to vasculopathy and tissue fibrosis. A lack of reliable biomarkers has been a challenge for clinical diagnosis of the disease. We employed a protein array-based approach to identify and validate SSc-specific autoantibodies. Phase I involved profiled autoimmunity using human proteome microarray (HuProt arrays) with 90 serum samples: 40 patients with SSc, 30 patients diagnosed with autoimmune diseases, and 20 healthy subjects. In Phase II, we constructed a focused array with candidates identified antigens and used this to profile a much larger cohort comprised of serum samples. Finally, we used a western blot analysis to validate the serum of validated proteins with high signal values. Bioinformatics analysis allowed us to identify 113 candidate autoantigens that were significantly associated with SSc. This two-phase strategy allowed us to identify and validate anti-small nuclear ribonucleoprotein polypeptide A (SNRPA) as a novel SSc-specific serological biomarker. The observed positive rate of anti-SNRPA antibody in patients with SSc was 11.25%, which was significantly higher than that of any disease control group (3.33%) or healthy controls (1%). In conclusion, anti-SNRPA autoantibody serves as a novel biomarker for SSc diagnosis and may be promising for clinical applications.

Prevalence and Clinical Implications of Scleroderma-Specific Autoantibodies in Seronegative Patients with Sicca Complaints

Introduction

Previous studies have revealed the presence of anticentromere antibodies in patients with Sjögren's syndrome (SS), predominantly in those serologically negative for antibodies against Ro/SSA and La/SSB antigens (seronegative). The prevalence and clinical significance of specific autoantibodies for Systemic Sclerosis (SSc) in seronegative patients with sicca complaints (dry eyes, dry mouth) have not yet been studied.

Aim of the study

Investigate the prevalence and clinical significance of SSc-specific autoantibodies in seronegative patients with sicca complaints.

Methods

Among 212 patients with sicca symptoms that were investigated at the Laboratory of Physiology, Medical School of Athens, National and Kapodistrian University of Athens between the years 2017-2020 for the presence of antibodies against Ro/SSA and La/SSB antigens, we found 106 patients that did not meet the criteria for SS following a thorough investigation. We have already performed serological tests of 13 specific autoantibodies for Scleroderma by using the test EUROLINE Systemic Sclerosis (Nucleoli) profile (IgG) (EUROIMMUNE Medizinische Labordiagnostika AG) in 51 of these patients. Additionally, their demographic, clinical, and laboratory data have been recorded.

Results

The presence of the specific SSc-specific autoantibodies was noticed in 29/51 patients (57%). More precisely, in 7/29 patients (24%) we recorded NOR90 as well as Th/To, in 5/29 (17%) Ku & Ro52, in 4/29 (14%) CENP-B, in 3/29 (10%) CENP-A & RP155, in 2/29 (7%) RP11 & PM/Scl 75 and finally in 1/29 (3.5%) Scl70, PM/Scl 100 & Fibrillarin respectively. The subsequent follow-up of these patients revealed signs of pulmonary hypertension and interstitial lung disease in some cases.

Conclusions

The high prevalence of Scleroderma-specific autoantibodies in seronegative sicca patients discloses those needing tighter follow-up and systematic treatment.

Microparticles: potential new contributors to the pathogenesis of systemic sclerosis?

BACKGROUND

Microparticles (MPs) are membrane-derived vesicles released from cells undergoing activation or apoptosis with diverse proinflammatory and prothrombotic activities, that have been implicated in the pathogenesis of systemic sclerosis (SSc). We aimed to evaluate the plasma levels of platelet-derived microparticles (PMPs), endothelial cell-derived microparticles (EMPs), and monocyte-derived microparticles (MMPs) in SSc patients, and the association between MPs and the clinical features of SSc.

METHODS

In this cross-sectional study, 70 patients with SSc and 35 age- and sex-matched healthy controls were evaluated. Clinical and nailfold capillaroscopy (NFC) data were obtained from all patients. Plasma levels of PMPs (CD42⁺/31⁺), EMPs (CD105⁺), and MMPs (CD14⁺) were quantified by flow cytometry.

RESULTS

Patients were mainly females (90%), with a mean age of 48.9 years old. PMP, EMP, and MMP levels were significantly increased in SSc patients compared to controls (79.2% ± 17.3% vs. 71.0% ± 19.8%, p = 0.033; 43.5% ± 8.7% vs. 37.8% ± 10.4%, p = 0.004; and 3.5% ± 1.3% vs. 1.1% ± 0.5%, p < 0.0001, respectively). PMP levels were significantly higher in patients with positive anti-topoisomerase-I antibodies (p = 0.030) and in patients with a disease duration > 3 years (p = 0.038). EMP levels were lower in patients with a higher modified Rodnan skin score (p = 0.015), and in those with an avascular score > 1.5 in NFC (p = 0.042).

CONCLUSION

The increased levels of PMPs, EMPs and MMPs in scleroderma patients might indicate a possible role for these agents in the pathogenesis of this challenging disease.

Progressive Systemic Sclerosis With Negative Antinuclear Antibodies and Absence of Raynaud’s Phenomenon: A Case Report and Literature Review

Systemic sclerosis (SSc) is typically characterized by positive antinuclear antibodies (ANA) and Raynaud's phenomenon (RP). We present the case of a male patient with progressive diffuse skin tightening, interstitial lung disease (ILD), pericardial tamponade, renal failure, and gastrointestinal dysmotility who was diagnosed with severe, rapidly progressive SSc despite negative ANA, absent RP, and a negative malignancy workup. The patient's clinical course was complicated by scleroderma renal crisis (SRC) requiring dialysis and eventual kidney transplantation. He also had severe gastrointestinal dysmotility requiring gastrostomy tube placement and total parenteral nutrition. Multiple agents were required for treatment, including mycophenolate mofetil (MMF) and rituximab. The patient eventually had improvement in his skin fibrosis and has been doing well in follow-up after kidney transplantation. Treatment of SSc can be challenging given the heterogeneity of the disease, and recognition of this subset of SSc patients is needed to help prevent early mortality among them.

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.

Normotensive scleroderma renal crisis as the presenting symptom of systemic sclerosis sine scleroderma: A case report

Scleroderma renal crisis is a rare but serious complication of systemic sclerosis. It is usually associated with marked hypertension and carries significant risk for morbidity and mortality. Its occurrence prior to the development of skin sclerosis is exceedingly rare. We report a case of a patient who presented with recurrent pericardial effusion and later tested positive for anti-nuclear and anti-topoisomerase antibodies. He later developed normotensive renal crisis as confirmed by kidney biopsy despite complete absence of skin involvement. To our knowledge, this is the first published case of a patient presenting with normotensive renal crisis without any skin involvement.

Worsening premature death burden gap from systemic sclerosis in men and black persons: A US nationwide population-based study

Objective

Male sex and black race incur poor prognosis in systemic sclerosis (SSc). There is no nationwide population-based assessment of premature SSc death burden by sex and race.

Methods

This is a population-based study comprising all recorded SSc deaths across the United States. We constructed histograms depicting the number of SSc deaths for each age by sex and race, and calculated the cumulative percent death at each age and the median age of death. We determined the odds ratios for the risk of premature death from SSc by sex and race. We then calculated the percent of total SSc deaths for different age groups by sex and race from 1970 to 2015. We performed chi-square test with Yates's correction and quantified the odds ratio (OR) with 95% confidence interval (CI).

Results

The median age of SSc death was 63 years in males versus 68 years in females, and 57 years in blacks versus 70 years in whites. The odds for SSc death before 65 years age was 1.8 (95% CI, 1.6-2.0) for males compared with females and 5.1 (95% CI, 4.4-6.0) for blacks compared with whites. The higher odds for premature death in males than in females was similar for both races. Differences in the proportions of premature deaths from 1970 to 2015 increased between males and females (-5% to 17%) and between blacks and whites (14% to 36%).

Conclusion

Males and black persons die of SSc at younger ages. The worsening premature death burden gap between the two sexes and races over the last five decades is troublesome.

Diagnostic accuracy and predictive value of autoantibody profiles in patients with systemic sclerosis: a single-center study

OBJECTIVE

To determine diagnostic accuracy and evaluate the predictive value of autoantibody profiles in patients with systemic sclerosis (SSc).

METHODS

A total of 140 patients with SSc (125 female, mean age 54.2 ± 14.2 years) were analyzed by a multiplex line immunoassay (Euroimmun) for autoantibodies against 12 SSc-related antigens. Associations between the presence of the autoantibodies and demographic clinical manifestations of patients with SSc were investigated.

RESULTS

The sensitivity and specificity of this assay were as follows: 32.9% and 99.4% for anti-Scl-70, 29.3% and 88.9% for anti-CENP A, 28.6% and 87.8% for anti-CENP B, 7.1% and 97.8% for anti-RP11, 5.7% and 100% for anti-RP155, 2.9% and 99.4% for anti-NOR 90, 2.9% and 98.9% for anti-Th/To, 1.4% and 96.7% for anti-PM-Scl-100, 5.0% and 98.3% for anti-PM-Scl-75, and 2.9% and 97.2% for anti-Ku, respectively. Anti-Scl-70 was significantly associated with sine scleroderma (P = 0.003), digital ulcers (P = 0.047), and Raynaud's phenomenon as the first clinical manifestation of onset (P = 0.017). SSc-ILD was more common in patients with anti-Scl-70 (P = 0.029) and less frequent in patients with anti-CENP A (P < 0.001) and anti-CENP B (P < 0.001). There was a significant association between PAH with anti-CENP A (P = 0.008) and anti-CENP B (P = 0.025). Renal involvement was significantly related to anti-NOR90 (P = 0.026) and anti-Th/To (P = 0.026).

CONCLUSIONS

This study confirmed the important role of autoantibodies in accurately diagnosing SSc. The autoimmune profile of patients with SSc was related to specific disease manifestations. Key Points • Autoantibody profiles were useful for diagnosing SSc and predicting clinical features of 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.

Toward Molecular Stratification and Precision Medicine in Systemic Sclerosis

Systemic sclerosis (SSc), a complex multi-systemic disease characterized by immune dysregulation, vasculopathy and fibrosis, is associated with high mortality. Its pathogenesis is only partially understood. The heterogenous pathological processes that define SSc and its stages present a challenge to targeting appropriate treatment, with differing treatment outcomes of SSc patients despite similar initial clinical presentations. Timing of the appropriate treatments targeted at the underlying disease process is critical. For example, immunomodulatory treatments may be used for patients in a predominantly inflammatory phase, anti-fibrotic treatments for those in the fibrotic phase, or combination therapies for those in the fibro-inflammatory phase. In advancing personalized care through precision medicine, groups of patients with similar disease characteristics and shared pathological processes may be identified through molecular stratification. This would improve current clinical sub-setting systems and guide personalization of therapies. In this review, we will provide updates in SSc clinical and molecular stratification in relation to patient outcomes and treatment responses. Promises of molecular stratification through advances in high-dimensional tools, including omic-based stratification (transcriptomics, genomics, epigenomics, proteomics, cytomics, microbiomics) and machine learning will be discussed. Innovative and more granular stratification systems that integrate molecular characteristics to clinical phenotypes would potentially improve therapeutic approaches through personalized medicine and lead to better patient outcomes.

Clinical and radiological features of lung disorders related to connective-tissue diseases: a pictorial essay

Connective tissue diseases (CTDs) include a spectrum of disorders that affect the connective tissue of the human body; they include autoimmune disorders characterized by immune-mediated chronic inflammation and the development of fibrosis. Lung involvement can be misdiagnosed, since pulmonary alterations preceded osteo-articular manifestations only in 20% of cases and they have no clear clinical findings in the early phases. All pulmonary structures may be interested: pulmonary interstitium, airways, pleura and respiratory muscles. Among these autoimmune disorders, rheumatoid arthritis (RA) is characterized by usual interstitial pneumonia (UIP), pulmonary nodules and airway disease with air-trapping, whereas non-specific interstitial pneumonia (NSIP), pulmonary hypertension and esophageal dilatation are frequently revealed in systemic sclerosis (SSc). NSIP and organizing pneumonia (OP) may be found in patients having polymyositis (PM) and dermatomyositis (DM); in some cases, perilobular consolidations and reverse halo-sign areas may be observed. Systemic lupus erythematosus (SLE) is characterized by serositis, acute lupus pneumonitis and alveolar hemorrhage. In the Sjögren syndrome (SS), the most frequent pattern encountered on HRCT images is represented by NSIP; UIP and lymphocytic interstitial pneumonia (LIP) are reported with a lower frequency. Finally, fibrotic NSIP may be the interstitial disease observed in patients having mixed connective tissue diseases (MCTD). This pictorial review therefore aims to provide clinical features and imaging findings associated with autoimmune CTDs, in order to help radiologists, pneumologists and rheumatologists in their diagnoses and management.

Contribution of HLA and KIR Alleles to Systemic Sclerosis Susceptibility and Immunological and Clinical Disease Subtypes

Systemic sclerosis (SSc) is an autoinflammatory, fibrotic condition of unknown aetiology. The presence of detectable autoantibodies against diverse nuclear antigens, as well as strong HLA associations with disease, suggest autoimmune involvement, however the links between endogenous and exogenous risk factors and SSc pathology remain undetermined. We have conducted a genetic analysis of HLA inheritance in two independent and meta-analysed cohorts of 1,465 SSc cases and 13,273 controls, including stratified association analyses in clinical and autoantibody positive subgroups of disease. Additionally, we have used patient genotypes to impute gene dosages across the KIR locus, encoding paired activating and inhibitory lymphocyte receptors for Class I HLA ligands, to conduct the largest analysis of KIR-HLA epistatic interactions in SSc to date. We confirm previous Class II HLA associations with SSc risk and report a new Class I association with haplotype HLA-B*44:03-HLA-C*16:01 at genome-wide significance (GWS). We further report statistically significant HLA associations with clinical and serological subtypes of disease through direct case-case comparison, and report a new association of HLA-DRB1*15:01, previously shown to bind topoisomerase-1 derived peptides, with anti-topoisomerase (ATA) positive disease. Finally, we identify genetic epistasis between KIRs and HLA class I ligands, suggesting genetic modulation of lymphocyte activation may further contribute to an individual’s underlying disease risk. Taken together, these findings support future functional investigation into endogenous immunological and environmental stimuli for disrupted immune tolerance in SSc.

Nailfold capillaroscopy for the early diagnosis of the scleroderma spectrum of diseases in patients without Raynaud's phenomenon

BACKGROUND

The utility of nailfold capillaroscopy in the evaluation of patients without Raynaud's phenomenon is unclear.

OBJECTIVE

This study aims to compare the utility of nailfold capillaroscopy for the early diagnosis of the scleroderma-spectrum of diseases in patients who present with Raynaud's phenomenon, undifferentiated non-Raynaud's phenomenon features and positive systemic sclerosis-associated antibodies without scleroderma-spectrum of disease features.

METHODS

Eligible patients were divided into three referral criteria groups: (I) Raynaud's phenomenon; (II) Undifferentiated non-Raynaud's phenomenon features and (III) Positive systemic sclerosis-associated autoantibodies without features to suggest scleroderma-spectrum of diseases. This includes systemic sclerosis, mixed connective tissue disease and dermatomyositis. The association between baseline scleroderma pattern on nailfold capillaroscopy (systemic sclerosis-nailfold capillaroscopy) and final diagnosis at follow-up was determined using logistic regression analysis. Test characteristics of nailfold capillaroscopy were compared and stratified by referral groups.

RESULTS

Of 95 patients followed-up for a mean of 1.6 years, 28 (29.5%) patients developed scleroderma-spectrum of diseases, 36 (37.9%) patients had suspected/other connective tissue disease and 27 (28.4%) patients had no connective tissue disease. Baseline systemic sclerosis-nailfold capillaroscopy was significantly associated with the development of scleroderma-spectrum of diseases in patients from Group I (odds ratio, 7.1, p = 0.01) and Group II (odds ratio 7.3, p = 0.005). In Group II patients, nailfold capillaroscopy had a sensitivity, specificity, positive and negative predictive values of 71.4%, 76.5%, 55.6% and 86.7%, respectively. Specificity (81.8%) and PPV (69.2%) were the highest in Group I patients. Nailfold capillaroscopy had the highest negative predictive value in Group III (100%), followed by Group II (86.7%) and Group I (78.3%) patients.

CONCLUSION

In addition to evaluating patients with Raynaud's phenomenon, nailfold capillaroscopy was useful in the evaluation and exclusion of scleroderma-spectrum of diseases in patients with undifferentiated non-Raynaud phenomenon features and those with systemic sclerosis-associated antibodies without features to suggest scleroderma-spectrum of diseases.

Systemic sclerosis in Asians: Are there racial differences?

Systemic sclerosis is a multisystemic autoimmune disease characterized by vasculopathy and fibrosis. Racial factors exert a significant influence on the epidemiology, clinical manifestations, antibody profile, mortality and genetic factors in systemic sclerosis. In this review, we examined Asian systemic sclerosis cohorts reported in Asia and multi-racial cohort studies to evaluate the disease characteristics and outcomes of systemic sclerosis in Asians. Asian patients have distinct genetic susceptibility to systemic sclerosis, younger age of systemic sclerosis onset, higher frequency of diffuse skin involvement, different autoantibody profiles such as higher frequency of anti-Scl70 and anti-U1-RNP antibodies, and more severe clinical phenotype. There was a suggestion of poorer survival among Asians that may be contributed by more severe disease, socioeconomic factors and differences in healthcare systems. Recognizing the influence of racial differences in systemic sclerosis disease course is important as it has implications for appropriate treatment, monitoring and prognostication.

Exosome circRNAs and ceRNA network profiles in different ANA sera

Increasing evidences show that circRNAs are associated with some autoimmunity diseases either as a biomarker or therapeutic target. Exosomes containing nucleic acids and proteins are found in sera of series diseases and could serve as either diagnostic or therapeutic target. ANA serves as first common diagnostic test for autoimmunity disease, different ANA staining reflecting different types of autoimmunity disease. Till now, whether different ANA sera exosomes express different circRNAs and relevant ceRNA networks are still shortage of investigation. This study analyzed circRNAs, miRNAs, and their interaction networks in different ANA sera exosomes by high-throughput sequencing. It found no significant difference of total circRNAs and miRNAs amount across different ANA sera exosomes. However, significant differences were found of circRNAs, miRNA constituents, function analysis by KEGG and GO, and their ceRNA networks including miRNA-circRNA and miRNA-mRNA among different ANA sera exosomes, suggesting sera exosome circRNAs as either biomarker or mechanism of autoimmunity diseases.

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.

Clinical characteristics associated with small airways disease in systemic sclerosis

Objective:

Pulmonary manifestations of systemic sclerosis are a major cause of morbidity and mortality. Small airways disease can cause dyspnea and pulmonary function test abnormalities. We aimed to determine the prevalence of small airways disease and describe the characteristics associated with small airways disease in a cohort of systemic sclerosis patients.

Methods:

We performed a retrospective cohort study of adults with systemic sclerosis who met American College of Rheumatology/European League Against Rheumatism 2013 classification criteria and were evaluated at our institution between November 2000 and November 2015. Patients with prior lung transplantation were excluded. Small airways disease was defined as the presence of one or more of the following: airway-centered fibrosis on surgical lung biopsy, forced expiratory volume at 25–75% ⩽ 50% on pulmonary function tests, and/or high-resolution computed tomography scan of the chest with bronchiolitis, mosaic attenuation, or air trapping on expiratory views. The primary outcome was small airways disease diagnosis. We performed multivariable logistic regression to determine the association of clinical variables with small airways disease.

Results:

One-hundred thirty-six systemic sclerosis patients were included; 55 (40%) had small airways disease. Compared to those without small airways disease, a significantly greater proportion of those with small airways disease had interstitial lung disease, chronic obstructive pulmonary disease, pulmonary hypertension, and gastroesophageal reflux disease. On multivariable analysis, pulmonary hypertension (odds ratio = 2.91, 95% confidence interval = 1.11–7.65, p-value = 0.03), gastroesophageal reflux disease (odds ratio = 2.70, 95% confidence interval = 1.08–6.79, p-value = 0.034), and anti-topoisomerase I (anti-Scl-70) antibody positivity (odds ratio = 0.42, 95% confidence interval = 0.19–0.93, p-value = 0.033) were associated with diagnosis of small airways disease.

Conclusion:

Small airways disease is prevalent among systemic sclerosis patients; those with pulmonary hypertension or gastroesophageal reflux disease may have a higher risk of small airways disease.

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.

High-Resolution Computed Tomography and Lung Ultrasound in Patients with Systemic Sclerosis: Which One to Choose?

Imaging plays a pivotal role in systemic sclerosis for both diagnosis management of pulmonary complications, and high-resolution computed tomography (HRCT) is the most sensitive technique for the evaluation of systemic sclerosis-associated interstitial lung disease (SSc-ILD). Indeed, several studies have demonstrated that HRCT helps radiologists and clinicians to make a correct diagnosis on the basis of recognised typical patterns for SSc-ILD. Most SSc patients affected by ILD have a non-specific interstitial pneumonia pattern (NISP) on HRCT scan, whilst a minority of cases fulfil the criteria for usual interstitial pneumonia (UIP). Moreover, several recent studies have demonstrated that lung ultrasound (LUS) is an emergent tool in SSc diagnosis and follow-up, although its role is still to be confirmed. Therefore, this article aims at evaluating the role of LUS in SSc screening, aimed at limiting the use of CT to selected cases.

High-Resolution Computed Tomography: Lights and Shadows in Improving Care for SSc-ILD Patients

The diagnosis and classification of systemic sclerosis-associated interstitial lung disease (SSc-ILD) is essential to improve the prognosis of systemic sclerosis (SSc) patients. The risk-stratification of disease severity and follow-up requires a multidisciplinary approach, integrating high-resolution computed tomography (HRTC) of the lung, pulmonary function tests (PFT), along with clinical and symptomatic evaluations. The use of HRCT in detecting SSc-ILD is not so much based on a definitive validation, but rather reflects the widespread clinician recognition of dissatisfaction with other modalities. However, due to the heterogeneity of SSc-ILD and the potential absence of symptoms in early or mild disease, it is prudent to consider as many parameters as possible in the assessment and monitoring of newly diagnosed patients. An early diagnosis meets the primary goal, i.e., the prevention of disease progression. The current first line treatment regimens are mainly centered on immunosuppressive therapy. This review assesses the role HRCT plays in optimizing care and improving clinical outcomes in SSc-ILD patients.

Trends in Systemic Sclerosis Mortality Over Forty-Eight Years, 1968-2015: A US Population-Based Study

OBJECTIVE

To identify secular trends associated with systemic sclerosis (SSc) mortality over a 48-year period.

METHODS

Using national mortality data compiled by the Centers for Disease Control and Prevention's Wide-Ranging Online Data for Epidemiologic Research, and population data from the US Census Bureau, we calculated an age-standardized mortality rate (ASMR) for SSc and non-SSc (all other causes), and we also calculated the ratio of the SSc ASMR to the non-SSc ASMR for each year from 1968 to 2015. We then used a joinpoint regression model to evaluate mortality trends overall and by sex and race.

RESULTS

From 1968 to 2015, there were 46,798 deaths with SSc recorded as the "underlying" cause of death and 106,058,839 non-SSc deaths. There were an additional 9,063 deaths with SSc recorded as a "contributing" cause of death from 1999 to 2015. Whereas the non-SSc ASMR decreased throughout the 48-year time period, the SSc ASMR increased from 1968 to 2000, followed by decreases each year from 2001 to 2015. The SSc ASMR also decreased for deaths where SSc was a contributing cause from 1999 to 2015. Women and Black persons had higher SSc ASMRs and SSc ASMR to non-SSc ASMR ratios than men and White persons, respectively. Additionally, SSc ASMRs and SSc ASMR to non-SSc ASMR ratios increased at higher rates in women and White persons than in men and Black persons, respectively, during the initial three decades.

CONCLUSION

Mortality attributable to SSc increased from 1968 to 2000, followed by a steady decline from 2001 to 2015. However, SSc mortality relative to non-SSc mortality remains high. SSc mortality has disproportionately changed by sex and race over the 48-year period assessed in the present study.

Anticentromere antibody induced by immunization with centromere protein and Freund's complete adjuvant may interfere with mouse early-stage embryo

BACKGROUND

Anticentromere antibody (ACA) is a member of the antinuclear antibody spectrum (ANAs) which has been speculated to be associated with subfertility. Thus, the present study aimed to investigate the induction of ACA production and its potential interference with early-stage embryos.

METHODS

Recombinant centromere protein-A (CENP-A) or centromere protein-B (CENP-B) and complete Freund's adjuvant (CFA) were used to immunize mice. Serum ACA level was then evaluated by using an indirect immunofluorescence test. Immunofluorescence assay was performed to detect IgG in follicles in ovarian tissues and early-stage embryos.

RESULTS

Following treatment, serum positive ACA was observed in mice treated with CENP and CFA. Furthermore, IgG were detected in follicular fluid and early-stage embryos from mice treated with CENP and CFA.

CONCLUSIONS

This study preliminarily indicated that ACA induced by CENP and CFA may penetrate into the living embryos of early-stage in mice.

Autoantibodies targeting telomere-associated proteins in systemic sclerosis

OBJECTIVES

Systemic sclerosis (SSc) is an autoimmune fibrotic disease affecting multiple tissues including the lung. A subset of patients with SSc with lung disease exhibit short telomeres in circulating lymphocytes, but the mechanisms underlying this observation are unclear.

METHODS

Sera from the Johns Hopkins and University of California, San Francisco (UCSF) Scleroderma Centers were screened for autoantibodies targeting telomerase and the shelterin proteins using immunoprecipitation and ELISA. We determined the relationship between autoantibodies targeting the shelterin protein TERF1 and telomere length in peripheral leucocytes measured by qPCR and flow cytometry and fluorescent in situ hybridisation (Flow-FISH). We also explored clinical associations of these autoantibodies.

RESULTS

In a subset of patients with SSc, we identified autoantibodies targeting telomerase and the shelterin proteins that were rarely present in rheumatoid arthritis, myositis and healthy controls. TERF1 autoantibodies were present in 40/442 (9.0%) patients with SSc and were associated with severe lung disease (OR 2.4, p=0.04, Fisher's exact test) and short lymphocyte telomere length. 6/6 (100%) patients with TERF1 autoantibodies in the Hopkins cohort and 14/18 (78%) patients in the UCSF cohort had a shorter telomere length in lymphocytes or leukocytes, respectively, relative to the expected age-adjusted telomere length. TERF1 autoantibodies were present in 11/152 (7.2%) patients with idiopathic pulmonary fibrosis (IPF), a fibrotic lung disease believed to be mediated by telomere dysfunction.

CONCLUSIONS

Autoantibodies targeting telomere-associated proteins in a subset of patients with SSc are associated with short lymphocyte telomere length and lung disease. The specificity of these autoantibodies for SSc and IPF suggests that telomere dysfunction may have a distinct role in the pathogenesis of SSc and pulmonary fibrosis.

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.

Anti-centromere antibody levels and isotypes and the development of systemic sclerosis

Objective

Little is known on the disease course of very early systemic sclerosis (SSc). Among the information yet to be elucidated is whether anticentromere antibody (ACA) isotype levels can serve as biomarkers for future SSc development and for organ involvement. This study was undertaken to evaluate whether IgG, IgM, and IgA ACA levels in IgG ACA–positive patients are associated with disease severity and/or progression from very early SSc to definite SSc.

Methods

IgG ACA–positive patients from 5 different cohorts who had very early SSc or SSc fulfilling the American College of Rheumatology (ACR)/European Alliance of Associations for Rheumatology (EULAR) 2013 criteria were included. A diagnosis of very early SSc was based on the presence of IgG ACAs and Raynaud’s phenomenon, and/or puffy fingers and/or abnormal nailfold capillaroscopy, but not fulfilling the ACR/EULAR 2013 criteria for SSc. Multivariable regression analyses were performed to determine the association between baseline ACA isotype levels and progression to definite SSc with organ involvement.

Results

Six hundred twenty‐five IgG ACA–positive patients were included, of whom 138 (22%) fulfilled the criteria for very early SSc and 487 (78%) had definite SSc. Levels of IgG ACAs (odds ratio 2.5 [95% confidence interval 1.8–3.7]) and IgM ACAs (odds ratio 1.8 [95% confidence interval 1.3–2.3]) were significantly higher in patients with definite SSc. Of 115 patients with very early SSc with follow‐up, progression to definite SSc occurred within 5 years in 48 (42%). Progression to definite SSc was associated with higher IgG ACA levels at baseline (odds ratio 4.3 [95% confidence interval 1.7–10.7]).

Conclusion

ACA isotype levels may serve as biomarkers to identify patients with very early SSc who are at risk for disease progression to definite SSc.

Broadening our understanding of genetic risk for scleroderma/systemic sclerosis by querying the chromatin architecture surrounding the risk haplotypes

BACKGROUND

Genetic variants in the human leukocyte antigen (HLA) locus contribute to the risk for developing scleroderma/systemic sclerosis (SSc). However, there are other replicated loci that also contribute to genetic risk for SSc, and it is unknown whether genetic risk in these non-HLA loci acts primarily on the vasculature, immune system, fibroblasts, or other relevant cell types. We used the Cistrome database to investigate the epigenetic landscapes surrounding 11 replicated SSc associated loci to determine whether SNPs in these loci may affect regulatory elements and whether they are likely to impact a specific cell type.

METHODS

We mapped 11 replicated SNPs to haplotypes and sought to determine whether there was significant enrichment for H3K27ac and H3K4me1 marks, epigenetic signatures of enhancer function, on these haplotypes. We queried pathologically relevant cell types: B cells, endothelial cells, fibroblasts, monocytes, and T cells. We then identified the topologically associated domains (TADs) that encompass the SSc risk haplotypes in primary T cells to identify the full range of genes that may be influenced by SSc causal SNPs. We used gene ontology analyses of the genes within the TADs to gain insight into immunologic functions that might be affected by SSc causal SNPs.

RESULTS

The SSc-associated haplotypes were enriched (p value < 0.01) for H3K4me1/H3K27ac marks in monocytes. Enrichment of one of the two histone marks was found in B cells, fibroblasts, and T cells. No enrichment was identified in endothelial cells. Ontological analyses of genes within the TADs encompassing the risk haplotypes showed enrichment for regulation of transcription, protein binding, activation of T lymphocytes, and proliferation of immune cells.

CONCLUSIONS

The 11 non-HLA SSc risk haplotypes queried are highly enriched for H3K4me1/H3K27ac-marked regulatory elements in a broad range of immune cells and fibroblasts. Furthermore, in immune cells, the risk haplotypes belong to larger chromatin structures encompassing genes that regulate a wide array of immune processes associated with SSc pathogenesis. Though importance of the vasculature in the pathobiology of SSc is widely accepted, we were unable to find evidence for genetic influences on endothelial cell function in these regions.

Anticentromere antibody induced by immunization with centromere protein a and Freund's complete adjuvant may interfere with mouse oocyte meiosis

BACKGROUND

Anticentromere antibody (ACA) is a member of the antinuclear antibody (ANA) family, and recent studies have found that ACA may be associated with oocyte maturation disorders; however, the possible mechanism behind this phenomenon remains unknown. We conducted this study to investigate whether ACA could penetrate into the living oocytes and interfere with oocyte meiosis in a mouse model.

METHODS

We divided mice into three groups: human recombinant centromere protein-A (human CENP-A, HA) and complete Freund's adjuvant (CFA) were used to immunize mice for the study group (HA + CFA), and mice injected with CFA (CFA group) or saline (Saline group), respectively, served as controls. After immunization, serum anti-CENP-A antibody was detected by indirect immunofluorescence assay (IIFT) and enzyme-linked immunosorbent assay (ELISA). Chromosome alignment and intracellular IgG localization in MI- and MII-stage oocytes were investigated by immunofluorescence analysis.

RESULTS

Positive ACAs were successfully induced by immunization with CENP-A and CFA, and results showed that the serum level of anti-CENP-A antibody was significantly higher in the HA + CFA group compared with the control groups. There was marked increase of chromosome misalignments in MI and MII oocytes in the HA + CFA group compared to the control groups. However, no oocytes from any of the three groups showed intracellular antibody immunofluorescence.

CONCLUSIONS

The development and maturation of oocytes were impaired in peripheral ACA positive mice, which exhibited severe chromosomal misalignments in metaphase meiosis; however, no evidence of ACAs entering the oocytes was observed, thus the underlying mechanism needs further exploration.

Scleroderma in Cairns: an epidemiological study

BACKGROUND

Systemic sclerosis (SSc) refers to an autoimmune fibrosing disorder with high disease burden and mortality. The prevalence of 23/100 000 in South Australia (SA) is among the highest documented, but anecdotally it is higher still in Cairns.

AIMS

To ascertain the prevalence of SSc in Cairns and surrounding regions, and to compare the demographic and clinical characteristics of patients with SSc in Cairns with those in SA.

METHODS

Patients with SSc in Cairns were ascertained through hospital records and by referrals from specialist physicians in the region. These patients were interviewed and completed a structured questionnaire. Their physical findings and autoantibodies were recorded. These patients were compared with the SA patients enrolled in the Australian Scleroderma Cohort Study.

RESULTS

A total of 81 patients was identified in Cairns, giving an estimated cross-sectional prevalence of 33.7/100 000. Among 65 patients interviewed in Cairns, 23 were born in Cairns, 16 had migrated to Cairns to ameliorate their Raynaud phenomenon and 26 for other reasons. The clinical features in both cohorts were similar, although Cairns had a lower prevalence of digital ulcers (30.8% vs 46.6%; odds ratio (OR) = 0.5035, 95% confidence interval (CI): 0.2839-0.8929, P = 0.0271) and higher prevalence of calcinosis (29.2% vs 17.0%; OR = 2.005, 95% CI: 1.055-3.382).

CONCLUSIONS

The higher prevalence of SSc in Cairns is partly, but not completely, due to migration. Differences in clinical features are not entirely explained by the warmer climate. There is a need for greater rheumatologic services in the Cairns region.

Anti-vinculin autoantibodies in systemic sclerosis: a step toward a novel biomarker?

Gastrointestinal (GI) disease is common in systemic sclerosis, and novel biomarkers are needed to identify and monitor these patients. Dr. Suliman and colleagues identify anti-vinculin autoantibodies in a subset of systemic sclerosis patients which associate with GI symptom severity, although more work is needed to determine their clinical utility.

Role of circulating endothelial cells in assessing the severity of systemic sclerosis and predicting its clinical worsening

Endothelial damage and fibro-proliferative vasculopathy of small vessels are pathological hallmarks of systemic sclerosis (SSc). The consequence is the detachment of resident elements that become circulating endothelial cells (CECs). The aim of our study was to evaluate the potential of CECs as biomarker in SSc. We enrolled 50 patients with limited cutaneous (lcSSc) and diffuse cutaneous (dcSSc) subset of SSc, who underwent clinical evaluation to establish the organ involvement. CECs were measured by flow-cytometry utilizing a polychromatic panel. An evident difference was observed in CEC counts comparing controls to SSc patients (median 10.5 vs. 152 cells/ml, p < 0.0001) and for the first time, between the two subsets of disease (median lcSSc 132 vs. dcSSc 716 CEC/ml, p < 0.0001). A significant correlation was established between CECs and some SSc clinical parameters, such as digital ulcers, skin and pulmonary involvement, presence of Scl-70 antibodies, nailfold videocapillaroscopy patterns and EUSTAR activity index. After 12 months, CECs correlated with clinical worsening of patients, showing that a number higher than 414 CEC/ml is a strong negative prognostic factor (RR 5.70). Our results indicate that CECs are a direct indicator of systemic vascular damage. Therefore, they can be used as a reliable marker of disease severity.

Suspected Aripiprazole-induced neutropenia in a geriatric patient: a case report

Background

Aripiprazole, a third-generation antipsychotic medication, has been used to treat a range of psychiatric disorders. According to the U.S. Food and Drug Administration’s prescribing information, the most common adverse reactions in adult patients in clinical trials (≥10%) were nausea, vomiting, constipation, headache, dizziness, akathisia, anxiety, and insomnia. While hematological adverse effects may occur with aripiprazole, there is very limited information in the published literature on such adverse outcomes.

Case presentation

A 68-year-old Caucasian male with treatment resistant depression was hospitalized for suicidal ideation. The patient developed neutropenia after aripiprazole was introduced as an augmentation agent. The neutropenia was reversible with discontinuation of the medication.

Conclusions

To our knowledge, we describe the first case report of suspected neutropenia-induced by aripiprazole use in a geriatric patient. While hematological adverse reactions are rare, we recommend adding CBC to the standard adverse systemic reaction monitoring of antipsychotic medications, particularly among the elderly.

Potential Biomarkers in Systemic Sclerosis: A Literature Review and Update

Systemic sclerosis (SSc) is a chronic autoimmune disease characterized by dysregulation of the immune system, vascular damage, and fibrosis of the skin and internal organs. Patients with SSc show a heterogeneous phenotype and a range of clinical courses. Therefore, biomarkers that are helpful for precise diagnosis, prediction of clinical course, and evaluation of the therapeutic responsiveness of disease are required in clinical practice. SSc-specific autoantibodies are currently used for diagnosis and prediction of clinical features, as other biomarkers have not yet been fully vetted. Krebs von den Lungen-6 (KL-6), surfactant protein-D (SP-D), and CCL18 have been considered as serum biomarkers of SSc-related interstitial lung disease. Moreover, levels of circulating brain natriuretic peptide (BNP) and N-terminal pro-brain natriuretic peptide (NT-proBNP) can provide diagnostic information and indicate the severity of pulmonary arterial hypertension. Assessment of several serum/plasma cytokines, chemokines, growth factors, adhesion molecules, and other molecules may also reflect the activity or progression of fibrosis and vascular involvement in affected organs. Recently, microRNAs have also been implicated as possible circulating indicators of SSc. In this review, we focus on several potential SSc biomarkers and discuss their clinical utility.

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.

Firm Cutaneous Nodule on the Dorsal Hand: A Case Report on Fibroblastic Rheumatism

Fibroblastic rheumatism (FR) is a rare dermatoarthropathy of unknown etiology. It is characterized by the onset of firm cutaneous nodules in patients with rheumatologic symptoms such as arthralgias or symmetric polyarthritis. Clinicopathologic correlation is critical in establishing the diagnosis, as the clinical manifestations can resemble other fibrosing conditions. In this report, we review the clinical and histologic features of FR, as well as conditions similar to those of the case we present, with dermatologic and rheumatologic manifestations. As part of our research, a PubMed search of the following terms was performed: "arthralgia, arthritis, arthropathy, cutaneous, disease, fibroblast, fibrosing, nodule, rheumatism, and rheumatology". This report discusses a unique case of FR diagnosed in a 37-year-old man with a single cutaneous nodule.

The Transcription Factor SCX is a Potential Serum Biomarker of Fibrotic Diseases

Fibrosing diseases are causes of morbidity and mortality around the world, and they are characterized by excessive extracellular matrix (ECM) accumulation. The bHLH transcription factor scleraxis (SCX) regulates the synthesis of ECM proteins in heart fibrosis. SCX expression was evaluated in lung fibroblasts and tissue derived from fibrotic disease patients and healthy controls. We also measured SCX in sera from 57 healthy controls, and 56 Idiopathic Pulmonary Fibrosis (IPF), 40 Hypersensitivity Pneumonitis (HP), and 100 Systemic Sclerosis (SSc) patients. We report high SCX expression in fibroblasts and tissue from IPF patients versus controls. High SCX-serum levels were observed in IPF (0.663 ± 0.559 ng/mL, p < 0.01) and SSc (0.611 ± 0.296 ng/mL, p < 0.001), versus controls (0.351 ± 0.207 ng/mL) and HP (0.323 ± 0.323 ng/mL). Serum levels of the SCX heterodimerization partner, TCF3, did not associate with fibrotic illness. IPF patients with severely affected respiratory capacities and late-stage SSc patients presenting anti-topoisomerase I antibodies and interstitial lung disease showed the highest SCX-serum levels. SCX gain-of-function induced the expression of alpha-smooth muscle actin (α-SMA/ACTA2) in fibroblasts when co-overexpressed with TCF3. As late and severe stages of the fibrotic processes correlated with high circulating SCX, we postulate it as a candidate biomarker of fibrosis and a potential therapeutic target.

Etiology, Risk Factors, and Biomarkers in Systemic Sclerosis with Interstitial Lung Disease

Systemic sclerosis (SSc) is a complex, multiorgan, autoimmune disease. Lung fibrosis occurs in ∼80% of patients with SSc; 25% to 30% develop progressive interstitial lung disease (ILD). The pathogenesis of fibrosis in SSc-associated ILD (SSc-ILD) involves cellular injury, activation/differentiation of mesenchymal cells, and morphological/biological changes in epithelial/endothelial cells. Risk factors for progressive SSc-ILD include older age, male sex, degree of lung involvement on baseline high-resolution computed tomography imaging, reduced Dl_CO, and reduced FVC. SSc-ILD does not share the genetic risk architecture observed in idiopathic pulmonary fibrosis (IPF), with key risk factors yet to be identified. Presence of anti-Scl-70 antibodies and absence of anti-centromere antibodies indicate increased likelihood of progressive ILD. Elevated levels of serum Krebs von den Lungen-6 and C-reactive protein are both associated with SSc-ILD severity and predict SSc-ILD progression. A promising prognostic indicator is serum chemokine (C-C motif) ligand 18. SSc-ILD shares similarities with IPF, although clear differences exist. Histologically, a nonspecific interstitial pneumonia pattern is commonly observed in SSc-ILD, whereas IPF is defined by usual interstitial pneumonia. The course of SSc-ILD is variable, ranging from minor, stable disease to a progressive course, whereas all patients with IPF experience progression of disease. Although appropriately treated patients with SSc-ILD have better chances of stabilization and survival, a relentlessly progressive course, akin to IPF, is seen in a minority. Better understanding of cellular and molecular pathogenesis, genetic risk, and distinctive features of SSc-ILD and identification of robust prognostic biomarkers are needed for optimal disease management.

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.

Comparative analysis of affected and unaffected areas of systemic sclerosis skin biopsies by high-throughput proteomic approaches

Background

Pathogenesis and aetiology of systemic sclerosis (SSc) are currently unclear, thus rendering disease prognosis, diagnosis and treatment challenging. The aim of this study was to use paired skin biopsy samples from affected and unaffected areas of the same patient, in order to compare the proteomes and identify biomarkers and pathways which are associated with SSc pathogenesis.

Methods

Biopsies were obtained from affected and unaffected skin areas of SSc patients. Samples were cryo-pulverised and proteins were extracted and analysed using mass spectrometry (MS) discovery analysis. Differentially expressed proteins were revealed after analysis with the Progenesis QIp software. Pathway analysis was performed using the Enrichr Web server. Using specific criteria, fifteen proteins were selected for further validation with targeted-MS analysis.

Results

Proteomic analysis led to the identification and quantification of approximately 2000 non-redundant proteins. Statistical analysis showed that 169 of these proteins were significantly differentially expressed in affected versus unaffected tissues. Pathway analyses showed that these proteins are involved in multiple pathways that are associated with autoimmune diseases (AIDs) and fibrosis. Fifteen of these proteins were further investigated using targeted-MS approaches, and five of them were confirmed to be significantly differentially expressed in SSc affected versus unaffected skin biopsies.

Conclusion

Using MS-based proteomics analysis of human skin biopsies from patients with SSc, we identified a number of proteins and pathways that might be involved in SSc progression and pathogenesis. Fifteen of these proteins were further validated, and results suggest that five of them may serve as potential biomarkers for SSc.

Genetic Susceptibility to Systemic Sclerosis in the Greek-Cypriot Population: A Pilot Study

Background: Systemic Sclerosis (SSc), also known as scleroderma, is an autoimmune rheumatic disease, which is clinically subdivided into two major subgroups; limited (lcSSc) and diffuse cutaneous scleroderma (dcSSc). Even though the SSc etiologies remains unclear, some HLA and non-HLA genetic variants have been associated with the disease. Aim: This study was designed to evaluate the associations between several HLA-related genetic variants and SSc in the Greek-Cypriot population. Methods: Forty-one SSc patients and 164 controls were genotyped at 18 selected single nucleotide polymorphisms (SNPs) using restriction fragment length polymorphism analyses, Sanger sequencing, and a multiplex SNaPshot minisequencing assay. Logistic regression analysis under the log-additive model was used to evaluate all possible associations between these SNPs and SSc; nominal statistical significance was assumed at p < 0.05. Results: Associations of SSc with SNPs rs3117230, rs3128930, and rs3128965 within the HLA-DPB1 and HLA-DPB2 regions were observed in the Greek-Cypriot population at the level of p < 0.05. However, none of these associations survived a Bonferroni correction. The direction of the effect is consistent with the direction reported in previous studies. In addition, allele frequencies of the majority of the selected SNPs in the Greek-Cypriot population are similar to those reported in the European population. Conclusion: This study initiates the genetic investigation of SSc in the Greek-Cypriot population, a relatively small newly investigated population. Further investigation with a larger sample size and/or additional SSc susceptibility loci may confirm the association of some of these variants with SSc in the Greek-Cypriot population that could potentially be used for predictive testing.

Autoantibodies as biomarkers for interstitial lung disease in idiopathic inflammatory myositis and systemic sclerosis: The case of anti-eIF2B antibodies

Objectives

Serum autoantibodies are pivotal for the early detection of systemic autoimmune rheumatic diseases such as Systemic Sclerosis (SSc) and Poly/Dermatomyositis (PM/DM), and in some cases are associated with organ complications such as interstitial lung disease (ILD). A paradigmatic example is provided by the autoantibody against the Eukaryotic Initiation Factor 2B (eIF2B) that has been recently detected in SSc.

Methods

Sera from 118 patients with SSc, 8 Poly/Dermatomyositis, 2 overlap SSc/Polymyositis, 4 undifferentiated connective tissue disease-UCTD and 3 healthy controls were tested first by indirect immunofluorescence for anti-nuclear antibodies-ANA pattern. Further, we employed protein-radioimmunoprecipitation (IP) and IP- Western Blot for the detection and confirmation of anti-eIF2B antibodies. Serum findings were further correlated with the clinical features of patients.

Results

We identified 3 SSc cases (2.5%) positive for anti-eIF2B antibodies while this autoantibody was not detected in control sera. Using protein-IP all three patients manifested the 38kD protein which is the antigenic target of anti-eIF2B antibodies, and this was associated with a cytoplasmic pattern at indirect immunofluorescence. The presence of anti-eIF2B was associated with ILD and a diffuse SSc variant, in one case in association with anti-Scl70/topoI.

Conclusions

Our data confirm that a small subgroup (2.5%) of patients with SSc have detectable anti-eIF2B with cytoplasmic-positive staining at immunofluorescence and this reactivity is associated with ILD.