Prevalence, correlates and clinical usefulness of antibodies to RNA polymerase III in systemic sclerosis: a cross-sectional analysis of data from an Australian cohort

Cancer in connective tissue disease

The association between cancer and autoimmunity is well-recognized, as represented by the increased incidence of cancer among patients with systemic autoimmune diseases; however, the underlying mechanisms remain only partially understood. On the one hand, malignancy may trigger a breakdown of immune tolerance in predisposed individuals, as autoimmune syndromes often emerge shortly after cancer diagnosis, suggesting that tumor antigens might initiate an autoimmune response. However, by involving persistent responses and the creation of a pro-inflammatory environment, the chronic immune activation characteristic of autoimmunity may promote oncogenesis. This scenario is further complicated by the use of immunosuppressive therapies for autoimmune conditions, which, as seen in transplant immunology, are associated with a higher risk of cancer, although data in rheumatology have not yielded definitive conclusions. Connective tissue diseases include systemic lupus erythematosus, primary Sjögren syndrome, idiopathic inflammatory myopathies, systemic sclerosis, mixed connective tissue disease, and undifferentiated forms. These conditions have been variably associated with an increased risk of cancer, both at the time of disease onset and in patients with long-standing autoimmune conditions, providing a paradigm for investigating this complex interplay. Despite recent progress, many unmet needs remain that warrant further research.

Small RNA and Toll-like receptor interactions: origins and disease mechanisms

Advances in small RNA sequencing have revealed diverse small noncoding RNAs (sncRNAs) beyond microRNAs (miRNAs), derived from transfer RNAs (tRNAs), ribosomal RNAs (rRNAs), small nuclear RNAs (snRNAs), and Y RNAs, carrying distinct RNA modifications. These emerging sncRNAs can function beyond RNA interference (RNAi), adopting aptamer-like roles by interacting with Toll-like receptors 7 and 8 (TLR7 and TLR8) via specific sequences, modifications, and structures. We propose a Sequential Activation Hypothesis where initial abnormal sncRNAs - triggered by infections or stresses - activate TLR7/8, leading to autoantibody production against autoantigens like RNA-binding proteins La and Ro. These autoantibody-antigen complexes further promote secondary immunogenic sncRNA production and repetitive TLR7/8 activation, perpetuating a vicious cycle sustaining autoimmunity. TLR7/8's X chromosome location and sex-biased expression contribute to female-dominant autoimmune diseases. Understanding sncRNA-TLR interactions is essential for designing novel therapeutic strategies.

Pilot Study of Diagnostic Performances of Vascular Biomarkers Soluble fms-Like Tyrosine Kinase and Placental Growth Factor in Scleroderma Renal Crisis

Introduction

Scleroderma renal crisis (SRC) is a major vascular complication of systemic sclerosis (SSc), associated with high morbidity and mortality. In this retrospective study, we evaluated the potential prognostic and diagnostic roles of angiogenesis molecules, placental growth factor (PlGF), soluble fms-like tyrosine kinase 1 (sFlt-1) and sFlt1/PlGF ratio as biomarkers in SRC.

Methods

Sera samples from 27 patients with a history of SRC (SSc-SRC+) were collected following event occurence. Biomarker levels were assessed using an electrochemiluminescence immunoassay and compared with age- and sex-matched patients with SSc-SRC- (n = 24), hemolytic uremic syndrome (HUS) (n = 27), malignant hypertension (MHT) (n = 22), and donors (n = 61). Areas under the receiver-operating-characteristic curves (AUC) were used to evaluate diagnostic accuracy. Long-term dialysis risk was evaluated using a Cox model.

Results

The median (interquartile range [IQR]) PlGF (pg/ml) was significantly higher in the serum of patients with SSc-SRC+ (42.1 [21.4-51.8]) compared with donors (14.7 [11.8-17.9]), those with SSc-SRC- (18.5 [14.7-21.5]) (P < 0.0001), those with HUS (22.8 [19.5-29.6]), and those with MHT (25.5 [17.2-39.3]) (P < 0.0001). In a multivariate regression adjusting for multiple confounders, PlGF was associated with higher SRC risk with an odds ratio of 1.08 [1.01-1.22], (P = 0.034). A PlGF level above 24.5 pg/ml revealed an AUC of 0.81 (confidence interval [0.68-0.94]), a specificity of 95%, and a sensitivity of 67% for SRC diagnosis. Eleven patients with SSc-SRC+ reached end-stage kidney failure with significantly higher PlGF (42.9 [22.4-78.2]) compared with patients who were dialysis-free (19.7 [15.6-29.7], P = 0.03).

Conclusion

Serum PlGF may identify the risk of SRC occurrence among patients with SSc with a good specificity and represents a potential tool for long-term dialysis risk evaluation.

Case report: Systemic sclerosis during neoadjuvant therapy for breast cancer in a 59-year-old woman

Systemic sclerosis (SSc) is an autoimmune connective tissue disease with skin fibrosis being the first and most common manifestation. Patients with SSc have a higher risk of developing malignant tumors than the general population. However, the sequence and underlying mechanisms linking SSc to malignancy remain controversial. This article presents the case of a 59-year-old woman who was diagnosed with SSc after developing skin fibrosis during neoadjuvant therapy for breast cancer. Despite aggressive antitumor treatments, including targeted therapy, SSc did not improve and progressed rapidly with increasing dermatofibrosis. Remarkably, the SSc entered remission following the cessation of antitumor therapy. Additionally, we reviewed the literature on SSc and malignant tumors, examined their relationship, and discussed key points regarding their identification and potential for adverse drug reactions.

The association between the neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, and monocyte-to-lymphocyte ratio and systemic sclerosis and its complications: a systematic review and meta-analysis

Introduction

The identification of new, easily measurable biomarkers might assist clinicians in diagnosing and managing systemic sclerosis (SSc). Although the full blood count is routinely assessed in the evaluation of SSc, the diagnostic utility of specific cell-derived inflammatory indices, i.e., neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and monocyte-to-lymphocyte ratio (MLR), has not been critically appraised in this patient group.

Methods

We conducted a systematic review and meta-analysis of studies investigating the NLR, PLR, and MLR, in SSc patients and healthy controls and in SSc patients with and without relevant complications. PubMed, Scopus, and Web of Science were searched from inception to 23 February 2024. Risk of bias and certainty of evidence were assessed using validated tools.

Results

In 10 eligible studies, compared to controls, patients with SSc had significantly higher NLR (standard mean difference, SMD=0.68, 95% CI 0.46 to 0.91, p<0.001; I2 = 74.5%, p<0.001), and PLR values (SMD=0.52, 95% CI 0.21 to 0.83, p=0.001; I2 = 77.0%, p=0.005), and a trend towards higher MLR values (SMD=0.60, 95% CI -0.04 to 1.23, p=0.066; I2 = 94.1%, p<0.001). When compared to SSc patients without complications, the NLR was significantly higher in SSc with interstitial lung disease (ILD, SMD=0.31, 95% CI 0.15 to 0.46, p<0.001; I2 = 43.9%, p=0.11), pulmonary arterial hypertension (PAH, SMD=1.59, 95% CI 0.04 to 3.1, p=0.045; I2 = 87.6%, p<0.001), and digital ulcers (DU, SMD=0.43, 95% CI 0.13 to 0.74, p=0.006; I2 = 0.0%, p=0.49). The PLR was significantly higher in SSc patients with ILD (SMD=0.42, 95% CI 0.25 to 0.59, p<0.001; I2 = 24.8%, p=0.26). The MLR was significantly higher in SSc patients with PAH (SMD=0.63, 95% CI 0.17 to 1.08, p=0.007; I2 = 66.0%, p=0.086), and there was a trend towards a higher MLR in SSc patients with ILD (SMD=0.60, 95% CI -0.04 to 1.23, p=0.066; I2 = 94.1%, p<0.001).

Discussion

Pending the results of appropriately designed prospective studies, the results of this systematic review and meta-analysis suggest that blood cell-derived indices of inflammation, particularly the NLR and PLR, may be useful in the diagnosis of SSc and specific complications.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42024520040.

The association of vasoactive-inotropic score and surgical patients' outcomes: a systematic review and meta-analysis

BACKGROUND

The objective of this study is to conduct a systematic review and meta-analysis examining the relationship between the vasoactive-inotropic score (VIS) and patient outcomes in surgical settings.

METHODS

Two independent reviewers searched PubMed, Web of Science, EMBASE, Scopus, Cochrane Library, Google Scholar, and CNKI databases from November 2010, when the VIS was first published, to December 2022. Additional studies were identified through hand-searching the reference lists of included studies. Eligible studies were those published in English that evaluated the association between the VIS and short- or long-term patient outcomes in both pediatric and adult surgical patients. Meta-analysis was performed using RevMan Manager version 5.3, and quality assessment followed the Joanna Briggs Institute (JBI) Critical Appraisal Checklists.

RESULTS

A total of 58 studies comprising 29,920 patients were included in the systematic review, 34 of which were eligible for meta-analysis. Early postoperative VIS was found to be associated with prolonged mechanical ventilation (OR 5.20, 95% CI 3.78-7.16), mortality (OR 1.08, 95% CI 1.05-1.12), acute kidney injury (AKI) (OR 1.26, 95% CI 1.13-1.41), poor outcomes (OR 1.02, 95% CI 1.01-1.04), and length of stay (LOS) in the ICU (OR 3.50, 95% CI 2.25-5.44). The optimal cutoff value for the VIS as an outcome predictor varied between studies, ranging from 10 to 30.

CONCLUSION

Elevated early postoperative VIS is associated with various adverse outcomes, including acute kidney injury (AKI), mechanical ventilation duration, mortality, poor outcomes, and length of stay (LOS) in the ICU. Monitoring the VIS upon return to the Intensive Care Unit (ICU) could assist medical teams in risk stratification, targeted interventions, and parent counseling.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42022359100.

Distinct Scleroderma Autoantibody Profiles Stratify Patients for Cancer Risk at Scleroderma Onset and During the Disease Course

OBJECTIVES

We examined whether an array of scleroderma autoantibodies associates with risk of cancer and could be useful tools for risk stratification.

METHODS

Scleroderma cancer cases and scleroderma controls without cancer from the Johns Hopkins Scleroderma Center and the University of Pittsburgh Scleroderma Center were studied. Sera were assayed by Lineblot and enzyme-linked immunosorbent assay (ELISA) for autoantibodies against centromere, topoisomerase 1, RNA polymerase (POLR) 3, PM/Scl, Th/To, NOR90, U3 RNP, Ku, Ro52, U1RNP, and RNPC3. Logistic regression models were constructed to examine whether distinct autoantibodies associated with overall cancer at any time and cancer-associated scleroderma (cancer occurring three years before and after scleroderma onset). The effects of having more than one autoantibody on cancer were further examined using random forest analysis.

RESULTS

A total of 676 cases and 687 controls were studied. After adjusting for relevant covariates, anti-POLR3 (odds ratio [OR] 1.47, 95% confidence interval [CI] 1.03-2.11) and monospecific anti-Ro52 (OR 2.19, 95% CI 1.29-3.74) were associated with an increased overall cancer risk, whereas anticentromere (OR 0.69, 95% CI 0.51-0.93) and anti-U1RNP (OR 0.63, 95% CI 0.43-0.93) were associated with lower risk. When examining risk of cancer-associated scleroderma, these immune responses remained associated with increased or decreased risk: anti-POLR3 (OR 2.28, 95% CI 1.33-3.91), monospecific anti-Ro52 (OR 2.58, 95% CI 1.05-6.30), anticentromere (OR 0.39, 95% CI 0.20-0.74), and anti-U1RNP (OR 0.32, 95% CI 0.11-0.93). Anti-Ro52 plus anti-U1RNP or anti-Th/To was associated with decreased cancer risk compared with anti-Ro52 alone.

CONCLUSIONS

These data suggest that five distinct scleroderma immune responses, alone or in combination, may be useful tools to stratify the risk of cancer for scleroderma patients. Further study examining cancer risk in autoantibody subgroups relative to the general population is warranted.

Interferon and autoantigens: intersection in autoimmunity

Interferon (IFN) is a key component of the innate immune response. For reasons that remain incompletely understood, the IFN system is upregulated in several rheumatic diseases, particularly those that feature autoantibody production, such as SLE, Sjögren's syndrome, myositis and systemic sclerosis. Interestingly, many of the autoantigens targeted in these diseases are components of the IFN system, representing IFN-stimulated genes (ISGs), pattern recognition receptors (PRRs), and modulators of the IFN response. In this review, we describe features of these IFN-linked proteins that may underlie their status as autoantigens. Note is also made of anti-IFN autoantibodies that have been described in immunodeficiency states.

Multi-Organ System Screening, Care, and Patient Support in Systemic Sclerosis

Systemic sclerosis (SSc) is a heterogenous systemic autoimmune disease of complex multi-organ manifestations with a disease-specific mortality of >50%. The patient journey is fraught with severe, diverse, and diffuse physical impairment, psychological burden, and diminishing health-related quality of life. SSc remains unfamiliar to many clinicians. Delayed/misdiagnosis, inadequate screening, and attention for common complications with potentially preventable disability/death contribute to patients feeling isolated and unsupported. We present actionable standards including screening, anticipatory guidance, and counseling in patient-centered SSc-care emphasizing psycho-social health as the central goal, whereas robust vigilance and efforts to improve biophysical health and survival are imperatives that support this goal.

Preventative Care in Scleroderma: What Is the Best Approach to Bone Health and Cancer Screening?

Systemic sclerosis (SSc) is a rare multisystem autoimmune disease characterized by fibrosis, vasculopathy, and autoimmunity. Lesser known complications inherent to SSc, such as malignancies and osteoporosis, can lead to decreased quality of life and increased morbidity and mortality. Patients with SSc have a greater risk of developing malignancies than the general population. In addition, they are more likely to be vitamin D deficient and are at great risk of osteoporosis-related fractures. However, these complications can be addressed through preventative measures. The purpose of this review is to provide clinicians with an approach to bone health and cancer screening in SSc.

Autoantibodies against PIP4K2B and AKT3 Are Associated with Skin and Lung Fibrosis in Patients with Systemic Sclerosis

Systemic sclerosis (SSc) is a rare autoimmune systemic disease that leads to decreased survival and quality of life due to fibrosis, inflammation, and vascular damage in the skin and/or vital organs. Early diagnosis is crucial for clinical benefit in SSc patients. Our study aimed to identify autoantibodies in the plasma of SSc patients that are associated with fibrosis in SSc. Initially, we performed a proteome-wide screening on sample pools from SSc patients by untargeted autoantibody screening on a planar antigen array (including 42,000 antigens representing 18,000 unique proteins). The selection was complemented with proteins reported in the literature in the context of SSc. A targeted antigen bead array was then generated with protein fragments representing the selected proteins and used to screen 55 SSc plasma samples and 52 matched controls. We found eleven autoantibodies with a higher prevalence in SSc patients than in controls, eight of which bound to proteins associated with fibrosis. Combining these autoantibodies in a panel could lead to the subgrouping of SSc patients with fibrosis. Anti-Phosphatidylinositol-5-phosphate 4-kinase type 2 beta (PIP4K2B)- and anti-AKT Serine/Threonine Kinase 3 (AKT3)-antibodies should be further explored to confirm their association with skin and lung fibrosis in SSc patients.

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.

Autoantibodies and Cancer Association: the Case of Systemic Sclerosis and Dermatomyositis

Several rheumatic diseases have a perplexing association with cancer. Unraveling this mysterious connection is likely to provide deeper understanding regarding mechanisms governing the onset of both autoimmunity and cancer immunity, in addition to providing clinicians much needed guidance around whom and when to screen for occult malignancy. Systemic sclerosis (scleroderma) and dermatomyositis are two diseases in which the association with internal malignancy is well-described and can be considered as models from which to gain important insights that likely have broader applicability. The past 15 years have witnessed a striking acceleration in understanding how these two diseases are related to cancer emergence-an important crack in this inscrutable armor has been the discovery and characterization of disease-specific autoantigens that are closely tied with risk of cancer emergence. The best-described examples of this are antibodies against anti-RNA polymerase III (anti-POL3) and transcription intermediary factor 1-gamma (anti-TIF1γ). Patients with systemic sclerosis and cancer that are diagnosed within a short time interval of each other frequently have anti-POL3 antibodies. Antibodies against the minor spliceosome protein RNA-Binding Region Containing 3 (RNPC3) are also associated with increased cancer incidence in systemic sclerosis. Similarly, in the dermatomyositis spectrum, the majority of anti-TIF1γ-associated cancers are detected around the time of DM onset (most often within 1 year). Antibodies against Nuclear Matrix Protein 2 are also potentially associated with increased cancer emergence in dermatomyositis. The systemic sclerosis/anti-POL3 connection with close cancer onset led to the first experiments directly supporting the concept that rheumatic disease may in fact be a manifestation of cancer. It is now clear that studying these diseases through the lens of autoantibodies can reveal relationships and insights that would otherwise remain obscured. Extending these studies, new findings show that antibodies against RNA polymerase I large subunit are associated with protection against short interval cancers in anti-POL3-positive systemic sclerosis patients. These insights highlight the fact that autoantigen discovery related to cancer emergence remains an important priority; such new tools will enable the testing of specific hypotheses regarding mechanisms governing disease emergence and development of effective anti-tumor responses. Autoantibody phenotype will likely play an important role in the development of cancer screening guidelines that are critically needed by clinicians taking care of these patients. In this review, we will summarize the current state of knowledge regarding the different ways in which autoantibodies are connected with systemic sclerosis/dermatomyositis and malignancy and highlight potential paths forward.

Kidney transplantation in systemic sclerosis: Advances in graft, disease, and patient outcome

Systemic sclerosis (SSc) is an immune-mediated rheumatic disease characterized by vascular abnormalities, tissue fibrosis, and inflammation. Renal disease occurring in patients with SSc may have a variable clinicopathological picture. However, the most specific renal condition associated with this disease is the scleroderma renal crisis (SRC), characterized by acute onset of renal failure and severe hypertension. SRC develops in about 20% of cases of SSc, especially in those patients with diffuse cutaneous disease. The prognosis of this condition is often negative, with a rapid progression to end-stage renal disease (ESRD). The advent of the antihypertensive angiotensin-converting enzyme inhibitors in 1980 was associated with a significant improvement in patients’ survival and recovery of renal function. However, the prognosis of these patients can still be improved. The dialytic condition is associated with early death, and mortality is significantly higher than among patients undergoing renal replacement therapy (RRT) due to other conditions. Patients with SRC who show no signs of renal functional recovery despite timely blood pressure control are candidates for kidney transplantation (KT). In this review, we reported the most recent advances in KT in patients with ESRD due to SSc, with a particular overview of the risk of disease recurrence after transplantation and the evolution of other disease manifestations.

Systemic Sclerosis-Specific Antibodies: Novel and Classical Biomarkers

Disease-specific autoantibodies are considered the most important biomarkers for systemic sclerosis (SSc), due to their ability to stratify patients with different severity and prognosis. Anti-nuclear antibodies (ANA), occurring in subjects with isolated Raynuad's phenomenon, are considered the strongest independent predictors of definite SSc and digital microvascular damage, as observed by nailfold videocapillaroscopy. ANA are present in more than 90% of SSc, but ANA negativity does not exclude SSc diagnosis: a little rate of SSc ANA negative exists and shows a distinct subtype of disease, with less vasculopathy, but more frequent lower gastrointestinal involvement and severe disease course. Anti-centromere, anti-Th/To, and anti-Topoisomerase I antibodies could be considered as classical biomarkers, covering about 60% of SSc and defining patients with well-described cardio-pulmonary complications. In particular, anti-Topoisomerase I represent a risk factor for development of diffuse cutaneous involvement and digital ulcers in the first 3 years of disease, as well as severe interstitial lung disease (ILD). Anti-RNA polymerase III is a biomarker with new clinical implications: very rapid skin thickness progression, gastric antral vascular ectasia, the occurrence of synchronous cancers, and possible association with silicone breast implants rupture. Moreover, novel SSc specific autoantibodies have been globally described in about 10% of "seronegative" SSc patients: anti-elF2B, anti-RuvBL1/2 complex, anti-U11/U12 RNP, and anti-BICD2 depict specific SSc subtypes with severe organ complications. Many autoantibodies could be considered markers of overlap syndromes, including SSc. Anti-Ku are found in 2-7% of SSc, strictly defining the PM/SSc overlap. They are associated with synovitis, joint contractures, myositis, and negatively associated with vascular manifestation of disease. Anti-U3RNP are associated with a well-defined clinical phenotype: Afro-Caribbean male patients, younger at diagnosis, and higher risk of pulmonary hypertension and gastrointestinal involvement. Anti-PM/Scl define SSc patients with high frequency of ILD, calcinosis, dermatomyositis skin changes, and severe myositis. The accurate detection of autoantibodies SSc specific and associated with overlap syndromes is crucial for patients' stratification. ANA should be correctly identified using indirect immunofluorescent assay and a standardized way of patterns' interpretation. The gold-standard technique for autoantibodies' identification in SSc is still considered immunoprecipitation, for its high sensitivity and specificity, but other assays have been widely used in routine practice. The identification of SSc autoantibodies with high diagnostic specificity and high predictive value is mandatory for early diagnosis, a specific follow-up and the possible definition of the best therapy for every SSc subsets. In addition, the validation of novel autoantibodies is mandatory in wider cohorts in order to restrict the gap of so-called seronegative SSc patients.

Systemic Scleroderma-Definition, Clinical Picture and Laboratory Diagnostics

(1) Background: Scleroderma (Sc) is a rare connective tissue disease classified as an autoimmune disorder. The pathogenesis of this disease is not fully understood. (2) Methods: This article reviews the literature on systemic scleroderma (SSc). A review of available scientific articles was conducted using the PubMed database with a time range of January 1985 to December 2021. (3) Results and Conclusions: The article is a review of information on epidemiology, criteria for diagnosis, pathogenesis, a variety of clinical pictures and the possibility of laboratory diagnostic in the diagnosis and monitoring of systemic scleroderma.

An Intradermal Spindle Cell Lipoma on the Plantar Hallux in a Patient With Scleroderma and Ehlers-Danlos Syndrome: A Case Report

Spindle cell lipoma (SCL) is a rare variant of lipomas, which predominantly occurs in the regions of shoulder and posterior neck but rarely on the toes. Epidemiological studies have demonstrated increased incidence of cancers in patients with scleroderma. A 28-year-old female with scleroderma and Ehlers-Danlos syndrome developed a painful, skin colored, raised, polypoid lesion on the plantar side of the left hallux for several years. The lesion was surgically excised. Pathological evaluation showed intradermal bland spindle cells associated with delicate ropey/refractile collagen bundles with strong and diffuse cytoplasmic expression of CD34 but negative expression of Rb and S-100, which are consistent with SCL. We report a first case of SCL on the plantar hallux in a young female patient with scleroderma and Ehlers-Danlos disease with clinical presentations, histopathology, and treatment to raise awareness of clinicians to this rare variant of lipomas.

Management of Endothelial Dysfunction in Systemic Sclerosis: Current and Developing Strategies

Systemic Sclerosis (SSc) is an autoimmune disease marked by dysregulation of the immune system, tissue fibrosis and dysfunction of the vasculature. Vascular damage, remodeling and inadequate endothelial repair are hallmarks of the disease. Since early stages of SSc, damage and apoptosis of endothelial cells (ECs) can lead to perivascular inflammation, oxidative stress and tissue hypoxia, resulting in multiple clinical manifestations. Raynaud's phenomenon, edematous puffy hands, digital ulcers, pulmonary artery hypertension, erectile dysfunction, scleroderma renal crisis and heart involvement severely affect quality of life and survival. Understanding pathogenic aspects and biomarkers that reflect endothelial damage in SSc is essential to guide therapeutic interventions. Treatment approaches described for SSc-associated vasculopathy include pharmacological options to improve blood flow and tissue perfusion and, more recently, cellular therapy to enhance endothelial repair, promote angiogenesis and heal injuries. This mini-review examines the current knowledge on cellular and molecular aspects of SSc vasculopathy, as well as established and developing therapeutic approaches for improving the vascular compartment.

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.

Association between autoantibodies in systemic sclerosis and cancer in a national registry

OBJECTIVE

A close temporal relationship between systemic sclerosis (SSc) onset and cancer has been reported in anti-RNA polymerase III-positive patients. We investigated the association between cancer and other SSc autoantibodies in a national SSc registry.

METHODS

SSc patients enrolled in the Canadian Scleroderma Research Group registry from 2004 to 2019 were characterized according to autoantibodies to centromere, topoisomerase I/Scl70, RNA polymerase III, fibrillarin, Th/To (hPOP1), PM/Scl, Ku, NOR90, Ro52/TRIM21 and U1RNP. Logistic regression was used to examine the association between a close cancer-SSc interval and autoantibody status, adjusted for age, sex, race and smoking history.

RESULTS

Of 1698 SSc patients, 1481 (87%) had available autoantibody data. Cancer was diagnosed within 2, 3 and 5 years of the first non-Raynaud manifestation in 1.3%, 2.1% and 3.5% of patients. The most frequent cancers diagnosed within 2 years were breast (33%), gynaecological (19%) and haematological (14%) cancers. The risk of cancer within 2 years was increased among anti-topoisomerase I (OR 3.43, 95% CI 1.04-10.05) and anti-U1-RNP-positive patients (OR 5.54, 95% CI 1.16-20.40), but not with anti-RNA polymerase III. None of the anti-fibrillarin, Th/To, PM/Scl, Ku and NOR90-positive patients had cancer within 2 years. Patients with anti-centromere or none of the tested autoantibodies had numerically lower risks of developing cancer within two years.

CONCLUSION

Synchronous cancer was rare in this large cohort of predominantly female and White SSc patients. The risk of cancer within 2 years was increased among anti-topoisomerase I and anti-U1-RNP-positive patients. Screening strategies guided by autoantibodies require further careful consideration.

Journey of a patient with scleroderma from renal failure up to kidney transplantation

The increased awareness of systemic sclerosis (SS) and its pathogenetic background made the management of this disease more amenable than previously thought. However, scleroderma renal crisis (SRC) is a rarely seen as an associated disorder that may involve 2%-15% of SS patients. Patients presented with earlier, rapidly progressing, diffuse cutaneous SS disease, mostly in the first 3-5 years after non-Raynaud clinical manifestations, are more vulnerable to develop SRC. SRC comprises a collection of acute, mostly symptomatic rise in blood pressure, elevation in serum creatinine concentrations, oliguria and thrombotic microangiopathy in almost 50% of cases. The advent of the antihypertensive angiotensin converting enzyme inhibitors in 1980 was associated with significant improvement in SRC prognosis. In a scleroderma patient maintained on regular dialysis; every effort should be exerted to declare any possible evidence of renal recovery. A given period of almost two years has been suggested prior to proceeding in a kidney transplant (KTx). Of note, SS patients on dialysis have the highest opportunity of renal recovery and withdrawal from dialysis as compared to other causes of end-stage renal disease (ESRD). KTx that is the best well-known therapeutic option for ESRD patients can also be offered to SS patients. Compared to other primary renal diseases, SS-related ESRD was considered for a long period of poor patient and allograft survivals. Pulmonary involvement in an SS patient is considered a strong post-transplant independent risk factor of death. Recurrence of SRC after transplantation has been observed in some patients. However, an excellent post-transplant patient and graft outcome have been recently reported. Consequently, the absence of extrarenal manifestations in an SS-induced ESRD patient can be accepted as a robust indicator for a successful KTx.

Updates on genetics in systemic sclerosis

Systemic sclerosis (SSc) is a complex disease, in which an interaction of genetic and environmental factors plays an important role in its development and pathogenesis. A number of genetic studies, including candidate gene analysis and genome-wide association study, have found that the associated genetic variants are mainly localized in noncoding regions in the expression quantitative trait locus and influence corresponding gene expression. The gene variants identified as a risk for SSc susceptibility include those associated with innate immunity, adaptive immune response, and cell death, while there are only few SSc-associated genes involved in the fibrotic process or vascular homeostasis. Human leukocyte antigen class II genes are associated with SSc-related autoantibodies rather than SSc itself. Since the pathways between the associated genotype and phenotype are still poorly understood, further investigations using multi-omics technologies are necessary to characterize the complex molecular architecture of SSc, identify biomarkers useful to predict future outcomes and treatment responses, and discover effective drug targets.

Primary CNS lymphoma in scleroderma: a case series

Many studies have demonstrated an increased risk of cancer in patients with rheumatologic diseases, including systemic sclerosis. Less explored is the role of immunosuppressive therapy as a contributing factor in cancer emergence or detection. This series introduces two cases of patients with systemic sclerosis who demonstrated clinical improvement in their rheumatic disease process with immunosuppression, but both of whom developed neurologic symptoms in the setting of decreasing or discontinuing immunosuppressive therapy, leading to the ultimate diagnosis of Epstein Barr Virus positive (EBV+) diffuse large B cell lymphoma of the CNS. To our knowledge, primary CNS lymphoma has not been previously described in systemic sclerosis patients. Immunosuppressive therapies could promote the development of virus-associated malignancies due to decreased viral clearance. We hypothesize that removing immunosuppression could allow the immune system to generate an inflammatory response to an underlying tumor or viral antigen, contributing to development of neurologic symptoms and detection of underlying disease.

Risk and prognosis factors for systemic sclerosis with lung cancer: A single-centre case-control study in China

OBJECTIVE

To analyse clinical characteristics, risk and prognosis factors for systemic sclerosis (SSc) patients with lung cancer.

METHODS

SSc patients with lung cancer admitted to Peking Union Medical College Hospital from February 1992 to December 2018 were included. Age and sex-matched controls were selected from a pool of SSc patients without lung cancer during the same period. Conditional logistic regression and Cox proportional-hazard regression were used to identify risk factors and prognosis factors. The Kaplan-Meier method was used to draw the survival curve and calculate median survival.

RESULTS

Nineteen SSc patients with lung cancer and 76 controls were included. The mean age at lung cancer diagnosis was 54.4 ± 10.2 years. In all 19 cases the lung cancer had been diagnosed after SSc and the median interval between SSc onset and lung cancer onset was 10.5 years (range 2.0-36.2 years). Among SSc patients with lung cancer, the median follow-up time and median survival were 2.6 years and 1.4 years, respectively. In the sex and age-matched conditional logistic multivariable regression analysis, family history of malignancy (OR 4.930, 95%CI 1.926-12.619, P = .001), ILD (OR 7.701, 95%CI 1.009-58.767, P = .049) were independent risk factors for lung cancer among SSc patients, and considering sex and age of SSc onset, SSc patients with more advanced staging of lung cancer (HR 3.190, 95%CI 1.127-6.126, P = .06) had poorer prognosis.

CONCLUSION

Lung cancer is not uncommon in SSc patients, especially those with family histories of malignancy or ILD. Early detection of lung cancer is of vital importance for better prognosis.

Increased malignancies in our Waikato cohort of patients with systemic sclerosis

BACKGROUND

Systemic sclerosis (SSc) has been associated with an increased risk of malignancy (especially in the skin, lung, breast, and hematological system).

AIM

To determine the risk of malignancies in our SSc cohort.

METHODS

The NZ National Cancer Registry supplied details of all malignancies recorded in patients attending the Waikato Hospital Systemic Sclerosis Clinics from 2005 to 2018. Prospectively gathered clinical data were used to look for associations between clinical variables and malignancy.

RESULTS

Out of the 164 patients in the Waikato SSc cohort, 32 (19.5%) had developed a malignancy. The overall standardized incidence rate was found to be 2.2 (95% CI 1.4-3.4) but was higher for men (4.4, 95% CI 1.4-10.3). The absolute numbers of patients with SSc and malignancies were small and were not adequately powered to investigate the SSc subgroups. The mean age of patients with malignancy was approximately 8 years older than patients without. The most common form of malignancy was skin (14, 43.7%), followed by breast (6, 18.7%), and lymphoma (5, 15.6%).

CONCLUSION

This study found an increased risk of malignancy for patients within the Waikato SSc cohort. Risk was greater in male patients and the mean age of patients with malignancies was approximately 8 years older than those without malignancy.

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.

Soluble Biomarkers for Prediction of Vascular and Gastrointestinal Disease Severity in Patients with Systemic Sclerosis

Purpose of Review

Disease severity biomarkers in patients with systemic sclerosis (SSc) provide an early and noninvasive screening tool to identify patients at increased risk for internal organ involvement that may impact diagnostic testing and treatment decisions. This review will focus on soluble SSc vascular and gastrointestinal disease biomarkers.

Recent Findings

Due to high morbidity and mortality associated with SSc pulmonary hypertension, multiple biomarkers are currently under investigation including serum autoantibodies, chemistries [such as N-terminal pro-brain natriuretic peptide (NT-proBNP)], proteins [midkine (MDK) and follistatin-like 3 (FSTL3)], chemokines [C-X-C motif ligand 4 (CXCL4) and C-C motif ligand 21 (CCL21)], plasma growth factors [vascular endothelial growth factor (VEGF) and placental growth factor (PlGF)], cell adhesion molecules [vascular cell adhesion molecule 1 (VCAM-1)], and endothelial microparticles [CD144+ endothelial microparticle (CD144+ EMP)]. A subset of these have also been proposed as SSc digital ulcer biomarkers [anti-endothelin-1 type A receptor (anti-ETAR), PlGF, and NT-proBNP]. A combination of NT-proBNP and high sensitivity cardiac troponins T (hs-cTnT) and I (hs-cTnI) may be useful for assessing primary SSc cardiac involvement. Putative SSc renal disease biomarkers include VEGF and endostatin levels; while anti-U1 and U3 ribonucleoprotein (anti-U1- and anti-U3-RNP) antibodies and fecal-calprotectin (F-calprotectin) are associated with GI involvement.

Summary

Serum autoantibodies are the mainstay SSc severity biomarkers, but new biomarkers are under investigation.

Advances at the Interface of Cancer and Systemic Sclerosis

The interface between systemic sclerosis (SSc) and cancer has offered valuable insights into our understanding of SSc disease pathogenesis. Defining SSc subgroups both temporally and serologically has been instrumental in stratifying cancer risk, with autoantibodies to RNA polymerase 3 (RNApol3), RNA polymerase I large subunit (RPA194), RNA Binding Region Containing 3 (RNPC3), and centromere identifying subgroups at increased or decreased risk of cancer. Clinically, improved subgrouping of SSc patients provides the opportunity to detect cancer at earlier stages of disease while increasing our efficiency of cancer assessment. Additional studies are needed to define the optimal approach to cancer screening in SSc, and validation studies in different cohorts will be needed to confirm all findings.

Antineutrophil Cytoplasmic Antibody-Associated Glomerulonephritis in a Case of Scleroderma After Recent Diagnosis With COVID-19

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a rare occurrence in systemic sclerosis (SSc) patients. AAV is an inflammatory disease that can lead to kidney failure due to the infiltration of mononuclear cells and the destruction of blood vessels. Also, crescentic glomerulonephritis (GN) has rarely been reported with coronavirus disease 2019 (COVID-19) and acute tubular injury is the most common renal pathology lesion in these patients. We present a rare case of a 46-year-old woman with SSc with new onset of renal failure after a recent diagnosis of COVID-19. Her serology was positive for p-ANCA and myeloperoxidase antibodies. Kidney biopsy was done and showed crescentic GN. We suggest during this pandemic, patients with an immunological disorder that are infected with COVID-19 be closely monitored for any organ involvement.

A 45-Year-Old Man with Scleroderma Renal Crisis Associated with a History of Systemic Sclerosis Sine Scleroderma

Patient: Male, 45-year-old

Final Diagnosis: Systemic sclerosis sine scleroderma

Symptoms: Hypertension • renal failure • shortness of breath

Medication: —

Clinical Procedure: —

Specialty: Nephrology • Rheumatology

Cancer risk in systemic sclerosis: identifying risk and managing high-risk patients

Introduction: Systemic sclerosis (SSc) is associated with a heightened cancer risk compared to the general population. Several pathways including immune system upregulation, cumulative inflammation, environmental factors, and genetic predisposition contribute to the development of both cancer and autoimmunity. Areas covered: This paper provides an overview of studies investigating the relationship between SSc and various types of cancer with a special focus on the identification of patients at higher risk for malignancy development. The demographic, serological, clinical, and disease-related characteristics of SSc individuals who are diagnosed with cancer over the course of their disease are discussed to provide a practical guidance for relevant screening strategies. Expert opinion: Several studies have identified subgroups of SSc patients at higher cancer risk based on the immunological profile (anti-RNAPol III positivity), diffuse disease type, and older age at SSc onset. Additionally, a close temporal association between SSc and cancer onset in certain antibody subsets raises the question as to whether more aggressive screening strategies should be considered. Currently, there are no published studies investigating the cost-effectiveness, efficacy, and safety of a targeted cancer-detection program. Screening procedures should at least follow recommendations for the general population with a special focus on patients at higher risk and specific cancer types.

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.

Biomarkers as an opportunity to stratify for outcome in systemic sclerosis

Systemic sclerosis (SSc) is a highly complex disease whose heterogeneity includes multiple aspects of the condition, such as clinical presentation, progression, extent and type of organ involvement, and clinical outcomes. Thus far, these features remain not easily predictable both at the patient group level and in a given patient with regard to age at onset and clinical course. The unpredictable clinical course represents an obstacle to focusing potentially effective treatment in patients that need it the most. At the time of organ involvement and clinical diagnosis, most of the clinical manifestations are irreversible; therefore, predicting outcomes becomes crucial. This can explain the multiple attempts to identify prognostic, predictive, and monitoring-both soluble and imaging-biomarkers over the past years. They range from the currently most used biomarkers, the autoantibodies associated with disease-specific clinical features and course, to the single recently proposed skin, lung, cardiac involvement biomarkers and to the composite scores capturing multiple aspects of the disease. This review will focus on soluble and imaging biomarkers that recently showed promising evidence for outcome stratification in patients with SSc.

Cancer and Scleroderma

Individuals with scleroderma have an increased risk of cancer compared with the general population. This heightened risk may be from chronic inflammation and tissue damage, malignant transformation provoked by immunosuppressive therapies, or a common inciting factor. In unique subsets of patients with scleroderma, there is a close temporal relationship between the onset of cancer and scleroderma, suggesting cancer-induced autoimmunity. This article discusses the potential mechanistic links between cancer and scleroderma, the serologic and clinical risk factors associated with increased cancer risk in patients with scleroderma, and implications for cancer screening.

Biphasic Temporal Relationship between Cancers and Systemic Sclerosis: A Clinical Series from Montpellier University Hospital and Review of the Literature

Cancer among patients with systemic sclerosis (SSc) would appear to be more prevalent than in the general population. Pathophysiological hypotheses are multiple, involving intertwined factors such as immune system antitumoral response, oxygen species dysregulation, and immunosuppressive treatments. We aimed to identify SSc patients with cancer monitored at our center, describing their clinical and immunological characteristics, such as cancer-specific outcomes. We focused in particular on the temporal relationships between cancer onset and SSc diagnosis. A retrospective study was conducted on SSc patients from Montpellier University Hospital from 2003 to 2018. Clinical characteristics and outcomes of each SSc patient with cancer were recorded. Fifty-five patients with SSc and at least one cancer was included (median age 56 years (47–66)), with a median follow-up time of 11 years (4–15). Sixty-four metachronous malignancies were identified (12 patients had two cancers). Among them, early-onset cancer occurrences (±5 years from SSc diagnosis) included 23 cancers (39% breast cancers, 13% lung cancers, and 13% gastro-intestinal tract cancers). Twenty-two cancers occurred 10 years (±5 years) after SSc diagnosis (14% breast cancers, 23% gastrointestinal (GI) tract cancers, and 18% lung cancers). Patients without any of the two autoantibodies (anti-centromere (ACA) and anti-topoisomerase (ATA-scl70) antibodies) were more prevalent in the early-onset cancer subgroup (14 vs. 6, p = 0.02). This study brought to light two peaks of cancer occurrence in SSc patients. Early-onset cancers were associated with SSc with a specific immunological signature. Late-onset cancers might be the consequence of a subtle interplay between repeated target organ inflammation, immunosuppressant use, mesenchymal cell dysfunction and subsequent genetic alterations.

Analysis of anti-RNA polymerase III antibodies in Chinese Han systemic sclerosis patients

OBJECTIVES

This study aimed to assess the prevalence and clinical correlation of anti-RNA polymerase III antibodies (anti-RNAP III) in Chinese Han systemic sclerosis (SSc) patients.

METHODS

Serum samples from 236 patients with SSc, 125 patients with connective tissue diseases (CTD), and 166 healthy controls (HCs), recruited from Peking Union Medical College Hospital and 21 other medical centers in China, were tested for antibodies to RNA polymerase III by means of a line immunoassay (LIA) or an enzyme-linked immunosorbent assay (ELISA) kit.

RESULTS

Anti-RNAP III antibodies were found in 14/236 SSc patients (5.93%), 1/125 (0.80%) CTD patients, and 0/166 (0.00%) HCs. The prevalence of anti-RNAP III was higher in SSc patients than in the CTD and HC groups (p = 0.02, p = 0.001, respectively). Renal crisis was significantly more common in patients with anti-RNAP III than patients without anti-RNAP III (42.9 vs. 4.1%, p < 0.0001). Gastrointestinal involvement was significantly more common in patients without anti-RNAP III than patients with anti-RNAP III (53.6 vs. 21.4%, p = 0.039). There was good agreement between the ELISA and line immunoassay (LIA) detection capabilities for anti-RNAP III.

CONCLUSIONS

The anti-RNAP III antibody, which was detected by ELISA, has diagnostic value for SSc and predictive value for SSc-related renal crisis. Both ELISA and LIA are very reliable methods for anti-RNAP III.Key Points• The prevalence of anti-RNAP III antibody was determined in Chinese SSc patients and performed ethnic differences.• The clinical association between anti-RNAP III antibody and Chinese SSc patients was evaluated in this research.• Methodological consistency of detection of anti-RNAP III antibody using commercial ELISA and LIA methods was evaluated in this research.

Protective Effect Against Cancer of Antibodies to the Large Subunits of Both RNA Polymerases I and III in Scleroderma

OBJECTIVE

While compelling data suggest a cancer-induced autoimmunity model in scleroderma patients with anti-RNA polymerase III large subunit (anti-RPC155) antibodies, ~85% of these patients do not manifest cancer. This study was undertaken to determine whether additional autoantigens are targeted in anti-RPC155-positive scleroderma patients without detectable cancer.

METHODS

The study included 168 scleroderma patients with anti-RPC155 antibodies (80 with a history of cancer and 88 with no cancer diagnosis after >5 years of follow-up). Thirty-five sera (17 from patients with cancer and 18 from patients without cancer) were randomly selected for autoantibody discovery using immunoprecipitation (IP). An ~194-kd band was enriched in the subgroup without cancer; this was identified as RNA polymerase I large subunit (RPA194).

RESULTS

RPA194 generated by in vitro transcription/translation was used for IPs performed on the entire cohort to test whether anti-RPA194 was enriched among anti-RPC155-positive patients without cancer. Anti-RPA194 antibodies were significantly more common in the group without cancer (16 [18.2%] of 88) than in the group with cancer (3 [3.8%] of 80) (P = 0.003). Patients with both anti-RPA194 and anti-RPC155 were significantly less likely to have severe gastrointestinal disease than patients with anti-RPC155 only (26.3% versus 51.0%; P = 0.043).

CONCLUSION

Anti-RPA194 antibodies are enriched in anti-RPC155-positive scleroderma patients without cancer. Since somatic mutations in the gene encoding RPC155 in cancer in scleroderma patients appears to play a role in immune response initiation against RPC155 in those patients, these data raise the possibility that the development of immune responses to both RPC155 and RPA194 may influence clinical cancer emergence. Further study is required to define whether different autoantibody combinations have utility as tools for cancer risk stratification in scleroderma.

Autoantibodies to a novel Rpp38 (Th/To) derived B-cell epitope are specific for systemic sclerosis and associate with a distinct clinical phenotype

Objective

Detection of antinuclear antibodies and specific autoantibodies is important in the diagnosis and classification of SSc. Several proteins of the Th/To complex, including Rpp25, Rpp38 and hPop1 are the target of autoantibodies in SSc patients. However, very little is known about the epitope distribution of this autoantigen. Consequently, we screened Rpp25, Rpp38 and hPop1 for B cell epitopes and evaluated their clinical relevance.

Methods

Serum pools with (n = 2) and without (n = 1) anti-Th/To autoantibodies were generated and used for epitope discovery. Identified biomarker candidate sequences were then utilized to synthesize synthetic, biotinylated, soluble peptides. The peptides were tested to determine reactivity with sera from SSc cohorts (n = 202) and controls (n = 159) using a chemiluminescence immunoassay. Additionally, samples were also tested for antibodies to full-length recombinant Rpp25 antibodies by chemiluminescence immunoassay.

Results

Several immunodominant regions were found on the three proteins. The strongest reactivity was observed with an Rpp38 peptide (aa 229–243). Autoantibodies to the Rpp38 peptide were detected in 8/149 (5.4%) limited cutaneous SSc patients, but not in any of 159 controls (P = 0.003 by two-sided Fisher's exact probability test). Although reactivity to the novel antigenic peptide was correlated with the binding to Rpp25 (rho = 0.44; P < 0.0001), subsets of patient sera either reacted strongly with Rpp25 or with the novel Rpp38-derived peptide.

Conclusion

A novel Rpp38 epitope holds promise to increase the sensitivity in the detection of anti-Th/To autoantibodies, thus enhancing the serological diagnosis of SSc.

Anti-RNA polymerase III antibody in lupus patients with proteinuria

BACKGROUND

To investigate the relationship between serum anti-ribonucleic acid polymerase III (anti-RNAP3) autoantibodies (Abs) and proteinuria severity in lupus patients.

METHODS

Serum antibodies reacting with anti-RNAP3 were measured in 49 systemic lupus erythematosus (SLE) patients (29 cases of SLE with proteinuria and 20 cases of SLE without proteinuria) and 10 healthy controls (HCs). For the patients, we recorded demographic data, daily urinary protein loss, serum anti-double strand deoxyribonucleic acid (anti-ds-DNA) antibodies, serum creatinine (Cr), estimated glomerular filtrating rate (eGFR), complement 3 (C3), and C4.

RESULTS

Fewer anti-RNAP3 antibodies were found in the SLE patients than in the HCs (p = 0.061). In the SLE with proteinuria group, positive correlations were observed among anti-RNAP3 antibodies and daily urinary protein loss, serum C3, C4, and eGFR, and negative correlations were observed between anti-RNAP3-Abs and anti-ds-DNA-Abs and serum Cr levels. However, these correlations were nonsignificant (p > 0.05).

CONCLUSION

This study demonstrated the possible role of anti-RNAP3 antibodies in SLE patients with proteinuria, as evidenced by their positive and negative relationships with daily urinary protein loss, eGFR, C3, C4, serum Cr, and anti-ds-DNA-Abs. Although these correlations were nonsignificant, our study builds a foundation for future tailored studies, and more in-depth studies with larger samples are warranted to provide more information.

Autoantibodies are present before the clinical diagnosis of systemic sclerosis

Systemic sclerosis (SSc) is a heterogeneous autoimmune disorder associated with vascular dysfunction and fibrotic changes in the skin, vasculature and internal organs. Although serologic abnormalities are an important diagnostic tool for SSc, little is known about whether autoantibodies precede clinical diagnosis. Here we investigated the presence of autoantibodies before SSc diagnosis and assessed whether certain autoantibodies might associate with the future onset of scleroderma renal crisis (SRC), a potentially fatal complication of the disease. Using the Department of Defense Serum Repository, autoantibodies were analyzed from archived, prospectively collected, longitudinal serum samples from sixteen individuals with SRC (SSc/SRC) and thirty cases of SSc without SRC (SSc/no SRC), matched for age, sex, and race. Seventy five percent (12/16) of the SSc/SRC and 40% (12/30) of the SSc/no SRC were seropositive for at least one autoantibody prior to clinical diagnosis (up to 27.1 years earlier, mean = -7.4 years). Although both disease groups demonstrated a heterogeneous immunoreactivity profile against the autoantigen panel, the SSc/SRC subjects showed two enriched clusters with one featuring elevated levels of autoantibodies against Ro52 and/or Ro60 and another with high levels of immunoreactivity against the RNA polymerase complex. Consistent with larger spectrum of immunoreactivity and the elevated levels of autoantibodies in SSc/SRC, the total response against the autoantigen panel from the last time point of the seropositive subjects revealed that the SSc/SRC cohort harbored higher antibody levels (p = 0.02) compared to SSc/no SRC. Overall, our findings demonstrate that relevant seropositive autoantibodies often precede the clinical diagnosis of SSc/no SRC and SSc/SRC.

Intriguing Relationships Between Cancer and Systemic Sclerosis: Role of the Immune System and Other Contributors

Systemic sclerosis (SSc) is an autoimmune connective tissue disorder, characterized by multisystem involvement, vasculopathy, and fibrosis. An increased risk of malignancy is observed in SSc (including breast and lung cancers), and in a subgroup of patients with specific autoantibodies (i.e., anti-RNA polymerase III and related autoantibodies), SSc could be a paraneoplastic syndrome and might be directly related to an immune response against cancer. Herein, we reviewed the literature, focusing on the most recent articles, and shed light onto the potential relationship between cancer and scleroderma regarding temporal and immunological dimensions.

Anticentromere Antibody-positive Scleroderma Renal Crisis Requiring Dialysis

A 70-year-old man with prior Raynaud's phenomena developed hypertension and renal insufficiency. Raynaud's phenomena, finger skin thickening, interstitial lung disease, and positive anticentromere antibody findings indicated systemic sclerosis (SSc). Based on the presence of SSc, severe hypertension with rapidly progressive renal failure, and proliferative and obliterative arteriolar vasculopathy, scleroderma renal crisis (SRC) was diagnosed. Despite good blood pressure control with antihypertensive drugs, hemodialysis was initiated and could not be withdrawn owing to unimproved renal dysfunction. Although SRC in anticentromere antibody-positive limited cutaneous SSc is extremely rare, some patients may develop SRC, and their renal prognosis may be poor.

Anti-RNA polymerase III antibodies in patients with suspected and definite systemic sclerosis: Why and how to screen

Anti-RNA Polymerase III antibodies are the most frequent anti-nuclear antibodies in systemic sclerosis, after anti-centromere and anti-Topoisomerase I. Considering their specificity for systemic sclerosis, they have been included in 2013 American College of Rheumatology/European League Against Rheumatism classification criteria for systemic sclerosis. They were first identified in 1993 using an immunoprecipitation method; the subsequent diffusion of commercial assays, based on the enzyme-linked immunosorbent assay or multiplex line immunoblot techniques, has allowed an increasing number of systemic sclerosis patients to be tested for this autoantibody; nevertheless, the diffusion of this test in systemic sclerosis patients is probably still sub-optimal. Anti-RNA Polymerase III antibodies have been associated with important clinical manifestations: rapid and diffuse cutaneous involvement, joint contractures, scleroderma renal crisis, gastric antral vascular ectasia and malignancies synchronous to systemic sclerosis onset. Moreover, other possible clinical associations, including pulmonary hypertension, still need confirmation. Since the correct approach for screening for anti- RNA Polymerase III antibodies in patients with suspected or definite systemic sclerosis is still debated, possible strategies are proposed here. Moreover, issues that are still controversial are discussed, including the interpretation of multiple simultaneous positivity for anti-RNA Polymerase III antibodies and other autoantibodies in line immunoassay, and the possible relevance of anti-RNA Polymerase III antibodies titre.