SSc-specific Autoantibodies Research Articles

Systemic sclerosis sine scleroderma is more aggressive in children than in adults.

To compare the clinical and laboratory features of paediatric SSc sine scleroderma (ssJSSc) with adult-onset ssSSc. Demographic, clinical and laboratory data of ssJSSc, retrospectively retrieved from our hospital medical records, case reports from the literature and from the Pediatric Rheumatology European Society JSSc registry, were compared with the Padua cohort of adult patients with ssSSc. Patients were defined as having ssSSc if they never had skin involvement but all the following features: (i) RP and/or digital vasculopathy, (ii) positive ANA, (iii) internal organs involvement typical of scleroderma and (iv) no other defined CTD. Eighteen juvenile and 38 adult-onset ssSSc patients, mean disease duration 5.8 and 9.7 years, respectively, entered the study. The frequency of females affected was significantly lower in ssJSSc (38.9% vs 89.5%, P < 0.0001). When compared with adults, ssJSSc displayed fewer SSc-specific capillaroscopy abnormalities (68.8% vs 94.7%, P = 0.02) while having significantly higher vascular (digital pitting scars, ulcers 35.3% vs 10.5%, P = 0.042), respiratory (50.0% vs 23.7%, P = 0.02) and cardiac (50.0% vs 2.6%, P < 0.0001) involvement. The outcome was significantly worse in ssJSSc as six patients (33%) died (n = 3) or reached an end-stage organ failure (n = 3) in comparison with only two deaths (5.3%) in the adult cohort. ACA were significantly lower in children (20.0% vs 68.4%, P = 0.001) while no difference was noted for other SSc-specific autoantibodies. Compared with adults where ssSSc generally has an indolent course, children present with aggressive disease that heralds a worse prognosis characterized by high cardiorespiratory morbidity and mortality.

Prognostic value of anti-IFI16 autoantibodies in pulmonary arterial hypertension and mortality in patients with systemic sclerosis

ObjectivesTo determine the diagnostic value of anti-interferon gamma inducible protein 16 (IFI16) autoantibodies in systemic sclerosis (SSc) patients negative for all tested SSc-specific autoantibodies (SSc-seronegative patients) and to evaluate the clinical significance of these autoantibodies, whether isolated or in the presence of anti-centromere autoantibodies (ACA). MethodsOverall, 58 SSc-seronegative and 66 ACA-positive patients were included in the study. All patients were tested for anti-IFI16 autoantibodies by an in-house direct ELISA. Associations between clinical parameters and anti-IFI16 autoantibodies were analysed. ResultsOverall, 17.2% of SSc-seronegative and 39.4% of ACA-positive patients were positive for anti-IFI16 autoantibodies. Anti-IFI16 autoantibodies were found only in patients within the limited cutaneous SSc (lcSSc) subset. A positive association between anti-IFI16 positivity and isolated pulmonary arterial hypertension (PAH) was found (odds ratio [OR]=5.07; p=0.014) even after adjusting for ACA status (OR=4.99; p=0.019). Anti-IFI16-positive patients were found to have poorer overall survival than negative patients (p=0.032). Cumulative survival rates at 10, 20 and 30 years were 96.9%, 92.5% and 68.7% for anti-IFI16-positive patients vs. 98.8%, 97.0% and 90.3% for anti-IFI16-negative-patients, respectively. Anti-IFI16-positive patients also had worse overall survival than anti-IFI16-negative patients after adjusting for ACA status in the multivariate Cox analysis (hazard ratio [HR]=3.21; p=0.043). ConclusionAnti-IFI16 autoantibodies were associated with isolated PAH and poorer overall survival. Anti-IFI16 autoantibodies could be used as a supplementary marker of lcSSc in SSc-seronegative patients and for identifying ACA-positive patients with worse clinical outcome.

Autoantibodies Targeting G-Protein-Coupled Receptors: Pathogenetic, Clinical and Therapeutic Implications in Systemic Sclerosis.

Systemic sclerosis (SSc) is a multifaceted connective tissue disease whose aetiology remains largely unknown. Autoimmunity is thought to play a pivotal role in the development of the disease, but the direct pathogenic role of SSc-specific autoantibodies remains to be established. The recent discovery of functional antibodies targeting G-protein-coupled receptors (GPCRs), whose presence has been demonstrated in different autoimmune conditions, has shed some light on SSc pathogenesis. These antibodies bind to GPCRs expressed on immune and non-immune cells as their endogenous ligands, exerting either a stimulatory or inhibitory effect on corresponding intracellular pathways. Growing evidence suggests that, in SSc, the presence of anti-GPCRs antibodies correlates with specific clinical manifestations. Autoantibodies targeting endothelin receptor type A (ETAR) and angiotensin type 1 receptor (AT1R) are associated with severe vasculopathic SSc-related manifestations, while anti-C-X-C motif chemokine receptors (CXCR) antibodies seem to be predictive of interstitial lung involvement; anti-muscarinic-3 acetylcholine receptor (M3R) antibodies have been found in patients with severe gastrointestinal involvement and anti-protease-activated receptor 1 (PAR1) antibodies have been detected in patients experiencing scleroderma renal crisis. This review aims to clarify the potential pathogenetic significance of GPCR-targeting autoantibodies in SSc, focusing on their associations with the different clinical manifestations of scleroderma. An extensive examination of functional autoimmunity targeting GPCRs might provide valuable insights into the underlying pathogenetic mechanisms of SSc, thus enabling the development of novel therapeutic strategies tailored to target GPCR-mediated pathways.

Autoantibodies to nuclear valosin-containing protein-like protein: systemic sclerosis-specific antibodies revealed by in vitro human proteome.

To identify and characterize undescribed systemic sclerosis (SSc)-specific autoantibodies targeting nucleolar antigens and to assess their clinical significance. We conducted proteome-wide autoantibody screening (PWAS) against serum samples from SSc patients with nucleolar patterned anti-nuclear antibodies (NUC-ANAs) of specific antibodies (Abs) unknown, utilizing wet protein arrays fabricated from in vitro human proteome. Controls included SSc patients with already-known SSc-specific autoantibodies, patients with other connective tissue diseases and healthy subjects. The selection of nucleolar antigens was performed by database search in the Human Protein Atlas. The presence of autoantibodies was certified by immunoblots and immunoprecipitations. Indirect immunofluorescence assays on HEp-2 cells were also conducted. Clinical assessment was conducted by retrospective review of electronic medical records. PWAS identified three candidate autoantibodies, including anti-nuclear valosin-containing protein-like (NVL) Ab. Additional measurements in disease controls revealed that only anti-NVL Abs are exclusively detected in SSc. Detection of anti-NVL Abs was reproduced by conventional assays such as immunoblotting and immunoprecipitation. Indirect immunofluorescence assays demonstrated homogeneous nucleolar patterns. Anti-NVL Ab-positive cases were characterized by significantly low prevalence of diffuse skin sclerosis and interstitial lung disease, compared with SSc cases with NUC-ANAs other than anti-NVL Abs, such as anti-U3-RNP and anti-Th/To Abs. Anti-NVL Ab is an SSc-specific autoantibody associated with a unique combination of clinical features, including limited skin sclerosis and lack of lung involvement.

Prevalence and Characteristics of Patients With Systemic Sclerosis Fulfilling the 2019 EULAR/American College of Rheumatology Classification Criteria for Systemic Lupus Erythematosus.

There is limited literature describing the overlap of systemic sclerosis (SSc) and systemic lupus erythematosus (SLE), and the studies have employed a range of case definitions. Our study used the new EULAR/American College of Rheumatology (ACR) SLE classification criteria to define SSc-SLE cases among our center's SSc cohort. This is a single-center, retrospective study of a previously described cohort of patients with SSc. Patient data were re-abstracted to evaluate for fulfillment of the 2019 EULAR/ACR classification criteria for SLE. Demographic, laboratory, clinical features, and mortality were compared among patients with SSc-SLE and patients with SSc alone. Among the 402 patients with SSc that were analyzed, 40 (10%) fulfilled the 2019 EULAR/ACR SLE classification criteria. Neuropsychiatric and renal involvement were rare. An initial SLE diagnosis was purported in 43% of the patients with SSc-SLE and 7% of patients with SSc alone (P < 0.001). Patients with SSc-SLE were more likely to be female, African American, and with limited cutaneous SSc. Anti-U1-RNP antibody positivity prevalence was 30% among patients with SSc-SLE and 6.6% among patients with SSc alone (P < 0.001). Death during follow-up occurred in 12 patients (30%) with SSc-SLE and in 81 patients (22%) with SSc alone, but there was no difference in survival among the groups per log rank test (P = 0.404). Ten percent of patients with SSc fulfill the 2019 EULAR/ACR classification criteria for SLE. These patients comprise a distinct demographic, serologic, and clinical phenotype but have similar severe SSc-specific end-organ damage and mortality as patients with SSc alone. Patients with SLE with Raynaud phenomenon should be evaluated for SSc-specific autoantibodies and scleroderma organ involvement.

Extended autoantibody panel in Turkish patients with early-stage systemic sclerosis: Coexpressions and their influences on clinical phenotypes.

To investigate the frequency and clinical relevance of an extended autoantibody profile in patients with systemic sclerosis(SSc). In this cross-sectional study, serum from 100 consecutive patients was subjected to indirect immunofluorescence (IIF)(HEp-20-10/primate liver mosaic) and Systemic Sclerosis Profile by EUROIMMUNto evaluate anti-nuclear antibodies(ANA) and autoantibodies against 13 different autoantibodies in patients with SSc less than 3 years. Ninety-three of 100 patients were positive for ANA byIIF. Fifty-three patients showed single positivity, 26 anti-topoisomerase antibodies (anti-Scl70 ab), 16 anticentromere antibodies (ACAs), six anti-RNA polymerase III antibodies (anti-RNAPIII ab), one anti-Ku antibody, one anti-PM/Scl100 antibody, two anti-PM/Scl75 antibodies, one anti-Ro52 antibody, whereas 32 patients had multiple autoantibody positivities. Among classic SSc-specific autoantibodies, anti-Scl70 and anti-RNAPIII abs showed the highest cooccurrence (n = 4). One patient was simultaneously positive for anti-RNAPIII ab and ACA, and one was positive for ACA and anti-Scl70 ab. The clinical features were not statistically different between single and multiple autoantibody-positivity for classic SSc-specific autoantibodies (ACA, anti-Scl70 ab, and anti-RNAPIII ab), except for digital ulcer in the multiantibody positive ACA group (p = .019). Based on our results, coexpression of autoantibodies is not uncommon in SSc patients. Although autoantibodies specific to SSc in early disease show generally known clinical features, it remains to be investigated how the coexpression of autoantibodies will affect clinical presentation.

Anti-nuclear valosin-containing protein-like autoantibody is associated with calcinosis and higher risk of cancer in systemic sclerosis.

Systemic sclerosis (SSc)-specific autoantibodies allow the diagnosis and predict the prognosis of SSc patients with different clinical characteristics. The aim of this study was to describe new SSc-related autoantibodies by a novel protein immunoprecipitation (IP) assay. Serum samples and clinical data were collected from 307 SSc patients. Antinuclear autoantibodies were tested in all patients by indirect immunofluorescence (IIF) on HEp-2 cells. SSc-specific autoantibodies were evaluated with a commercial immunoblot and chemiluminescence immunoassay, and traditional RNA-IP. Patients negative for all these autoantibodies (n = 51) were further tested with a non-radioactive protein IP assay. Protein bands detected on SDS-PAGE were then analysed by mass spectrometry (MS) and confirmed by western blot (WB). Additional 56 patients with nucleolar pattern by IIF were tested by protein IP-WB. Five patients who underwent protein IP testing showed a 110-115kDa molecular weight band on SDS-PAGE and a homogeneous nucleolar pattern by IIF. MS identified the bands as nuclear valosin-containing protein-like (NVL). An additional positive patient was detected by IP-WB. As compared with the remaining 101 negative patients, anti-NVL positive patients showed a greater prevalence of calcinosis (100% vs 18.9%, P < 0.001), and cancer (66.7% vs 8.9%, P = 0.002), with a particular association with synchronous cancer (OR = 16.3; P = 0.024). We identified NVL as a new autoantibody target by a novel protein IP assay in SSc patients with a homogeneous nucleolar IIF pattern, testing negative for all known SSc-specific autoantibodies by commercial assays and RNA IP. Anti-NVL identifies a new clinical phenotype, characterized by calcinosis and cancer.

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

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. Investigate the prevalence and clinical significance of SSc-specific autoantibodies in seronegative patients with sicca complaints. 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. 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. The high prevalence of Scleroderma-specific autoantibodies in seronegative sicca patients discloses those needing tighter follow-up and systematic treatment.

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.

Ways to predict interstitial lung disease in patients with systemic sclerosis: results of an observational study

In patients with systemic sclerosis (SSc), interstitial lung disease (ILD) is a factor in the decline of functional capacity up to disability and is also the leading cause of death. Therefore, one of the most important tasks in the treatment of this group of patients is not only to detect involvement of respiratory system, but also to predict the likelihood of its development.Objective: to study the possibility of predicting the development of ILD and advanced ILD in patients with SSc.Material and methods. The study included 79 patients with SSc (mean age 64.4±11.5 years; 94.9% women) from the Registry of myositis, SSc and Mixed Connective Tissue Diseases (РЕМИССиС) who underwent high-resolution computed tomography (HRCT) of the lungs. Classification trees (CTr) were constructed to predict the development of widespread ILD using the CHAID algorithm (exhaustive). All patients were tested for antibodies against Scl-70 (anti-Scl-70), CENP-B (anti-CENP-B), and PmScl (anti-PmScl).Results and discussion. ILD signs according to HRCT were detected in 53 patients. Fibrotic (34.2%) and cellular (15.2%) types of nonspecific interstitial pneumonia were the most common, and common interstitial pneumonia was less frequent (11.4%).The presence of ILD and advanced ILD (involvement of more than 20% of the lung parenchyma) were significantly associated with the detection of any autoantibodies, except anti-centromere antibodies, an increase in pulmonary artery systolic pressure, a decrease in forced vital capacity, diffusing capacity of the lungs, blood oxygen saturation at rest, and all parameters of six-minute walk test (6MWT), and complaints of shortness of breath. In addition, the presence of extensive ILD was also significantly associated with diffuse SSc and with SSc without skin manifestations.In establishing the CTr, it was found that the development of widespread ILD was unlikely in individuals who were able to walk more than 440 m in 6MWT and had neither anti-Scl-70 nor anti-PmScl.Significant associations were also found between the radiological pattern of ILD and the types of disease-specific antibodies.Conclusion. The 6MWT data in conjunction with the results of testing for SSc-specific autoantibodies provide a very accurate prediction of the presence and extent of ILD. It is advisable to include these indicators in the algorithm for screening and monitoring patients with SSc.

The diagnostic and prognostic value of a line immunoblot assay in Taiwanese patients with systemic sclerosis

Background and aimsWe aimed to evaluate the diagnostic performance and prognostic value of disease-specific antibodies and anti-Ro52 using a commercial line immunoblot assay (LIA) in Taiwanese patients with systemic sclerosis (SSc). Materials and methodsWe retrospectively enrolledall individuals at the Taichung Veterans General Hospital. We evaluated the diagnostic performance of LIA, anti-nuclear antibody (ANA) by indirect immunofluorescence (IIF) and also the association between the autoantibodies and the clinical phenotype using multivariable logistic regression. ResultsThe LIA exhibited a sensitivity of 65.4% and a specificity of 65.4%, at the optimal cutoff values of 2 + signal intensity. By taking the result of ANA into consideration, the optimal cutoff point was redefined as 1+. We observed a higher risk of diffuse cutaneous SSc (dcSSc) in those with negative autoantibodies, positive anti-Scl-70, anti-RNA polymerase III, and anti-Ro-52. Interstitial lung disease (ILD) was associated with negative autoantibodies, as well as positive anti-Scl-70 and anti-Ro52. Anti-Ro52 positivity was also associated with pulmonary arterial hypertension (PAH) and gastrointestinal tract involvement. ConclusionThe presence of anti-Ro52 or the absence of SSc-specific autoantibodies may potentially indicate advanced diseases in patients with SSc. The incorporation of both IIF and LIA testing may improve the diagnostic specificity of SSc.

Molecular typing of HLA-class II alleles reveals an association with autoantibodies and disease subsets of systemic sclerosis in a North Indian (Kashmir) population

To identify specific human leukocyte antigen (HLA)-Class II (DRB/DQB1/DPB1) alleles associated with systemic sclerosis (SSc) and to explore their relation with SSc autoantibodies, clinical manifestations, and disease subsets. HLA-class II alleles (DRB1/DRB3/DRB4/DRB5/DQB1) were determined by DNA typing in 80 SSc cases and 60 matched controls and HLA-DPB1 in 40 SSc patients and 30 controls by allele-specific-polymerase chain reaction with sequence-specific primers (PCR-SSP). The mean age of SSc patients was 36.9 ± 9.4 years; 76 females and 4 males (F:M 19:1) and a disease duration of 5.3 ± 3.3 years, they were 43(53.7%) limited and 37(46.2%) diffuse subtypes. SSc was significantly associated with DRB1*11, DRB1*01, DQB1*04, and DQB1*03*03 in a >4-fold manner, whereas DPB1*04 had a >7-fold increased risk compared to controls. There was a strong association between DRB1*11 (p = 0.04), DQB1*03*03 (p = 0.005), and DPB1*13 (p = 0.009) with anti-topoisomerase I (anti-topoI) whereas the frequency of DRB1*01 (p < 0.0001) was increased in patients with anti-centromere (ACA) positive SSc compared those negative (56% vs 25%; p < 0.0001). DRB1*03, DRB1*15, and DQB1*03*01 were SSc protective alleles in patients with positive ACA. Anti-topo I was associated with interstitial lung disease (ILD) (p < 0.01), whereas ACA with pulmonary arterial hypertension (PAH) (p = 0.01) and protection against ILD (p < 0.001). In addition, HLA-DRB1*03, DQB1*03*01and DPB1*03 were more frequent in patients with ILD than in patients without. Associations between specific HLA-class II alleles with certain SSc-specific autoantibodies (anti-topo I and ACA) were identified. Specific HLA associations with clinical and serological subtypes could serve as biomarkers of disease severity and progression in SSc.

Progression from suspected to definite systemic sclerosis and the role of anti-topoisomerase I antibodies

IntroductionEarly diagnosis of systemic sclerosis (SSc) is important to start therapeutic interventions timely. Important risk factors for progression to SSc are the SSc-specific autoantibodies, of whom anti-centromere antibodies (ACA) and...

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

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

Increased L-Selectin on Monocytes Is Linked to the Autoantibody Profile in Systemic Sclerosis.

Monocytes are known to be implicated in the pathogenesis of systemic sclerosis (SSc), as they exert prominent migratory, adhesive, and chemotactic properties. The aim of our study was to characterize the surface expression of adhesion/chemotactic molecules (CD62L, CD11b, CCR2, CCR5) on the SSc monocytes and determine correlations with the clinical presentation of SSc. We included 38 SSc patients and 36 healthy age-and sex-matched controls. Isolated monocytes, as well as in vitro serum-treated monocytes, were analyzed by flow cytometry; additionally, soluble CD62L was measured in serum. We found increased soluble CD62L in the SSc serum samples and increased CD62L on the surface of the SSc monocytes in the in the same set of patients. Among samples with determined SSc-specific autoantibodies, the surface CD62L was the lowest in patients positive for anti-PM/Scl autoantibodies and the highest in patients with anti-topoisomerase I autoantibodies (ATA). The treatment of isolated healthy monocytes with ATA-positive SSc serum resulted in increased surface CD62L expression. Moreover, surface CCR5 was reduced on the monocytes from SSc patients with interstitial lung disease but also, along with CCR2, negatively correlated with the use of analgesics/anti-inflammatory drugs and immunosuppressants. In conclusion, increased CD62L on SSc monocytes, particularly in ATA-positive patients, provides new insights into the pathogenesis of SSc and suggests CD62L as a potential therapeutic target.

Systemic Sclerosis in Zimbabwe: Autoantibody Biomarkers, Clinical, and Laboratory Correlates.

IntroductionSystemic sclerosis (SScl) is an autoimmune disease whose prevalence is rarely reported in Africa. Autoantibodies are the biomarkers of the condition, precede overt disease and determine disease phenotypes. SSc specific autoantibodies also vary between racial groupings. Objective: To investigate the clinical and laboratory characteristics of Zimbabwean patients who were reactive SSc specific autoantibodies.Materials and Method240 patients, 173 of them female with SSc specific autoantibodies were included. Autoantibodies were detected by indirect immunofluorescence microscopy and immunoblotting using a panel of 13 SScl (Euroimmun Ag., Germany). Demographic, clinical and laboratory parameters relevant to the monitoring of SScl were captured. These included pulmonary function tests, hematology, clinical chemistry, serology and thyroid function tests. Allergy skin prick tests (SPT) to inhalant and food allergen sources were conducted when indicated.ResultsAll the 240 patients (median age was 36 years) expressed SSc specific autoantibodies. 86% were Black, 11% White and 3% Asian and a fifth (20%) were younger than 16 years. Eleven (4.6%) fulfilled the ACR/EULAR classification of SSc. Clinically they had limited cutaneous (n=6), diffuse cutaneous (n=3) and SScl/inflammatory myopathy overlap (n=2). The most frequently detected antibodies anti-RNA polymerase III (RNAP) 55%, anti-Th/To (28%) anti-RNAP 11 (22%), anti-CENPB (18%) and anti-Scl-70/ATA (13%). Racial variations in the expression of these antibodies were apparent between Black, White and Asian patients. The majority (95%), who did not fulfil the ARA/EULAR criteria were symptomatic. Raynaud’s Phenomenon was documented in 24%. Respiratory symptoms included coughing, dyspnea and wheezing. There was a restrictive ventilatory defect with increased FEV1/FVC ratio. Pruritus, urticaria and skin depigmentation were the main cutaneous features while constipation, bloating, Gastroesophageal reflux disease (GERD) and abdominal pain dominated GI symptoms. Mean blood pressure readings while normal varied with biomarkers. Haematology and biochemistry parameters were within normal reference ranges.ConclusionThe expression of SSc specific autoantibodies is common and associated with known SSc symptoms. The types and frequency of autoantibodies varied with racial groupings. A fifth of the patients were children below the age of 16 years.

Oxidative Stress Induced by Reactive Oxygen Species (ROS) and NADPH Oxidase 4 (NOX4) in the Pathogenesis of the Fibrotic Process in Systemic Sclerosis: A Promising Therapeutic Target.

Numerous clinical and research investigations conducted during the last two decades have implicated excessive oxidative stress caused by high levels of reactive oxygen species (ROS) in the development of the severe and frequently progressive fibrotic process in Systemic Sclerosis (SSc). The role of excessive oxidative stress in SSc pathogenesis has been supported by the demonstration of increased levels of numerous biomarkers, indicative of cellular and molecular oxidative damage in serum, plasma, and other biological fluids from SSc patients, and by the demonstration of elevated production of ROS by various cell types involved in the SSc fibrotic process. However, the precise mechanisms mediating oxidative stress development in SSc and its pathogenetic effects have not been fully elucidated. The participation of the NADPH oxidase NOX4, has been suggested and experimentally supported by the demonstration that SSc dermal fibroblasts display constitutively increased NOX4 expression and that reduction or abrogation of NOX4 effects decreased ROS production and the expression of genes encoding fibrotic proteins. Furthermore, NOX4-stimulated ROS production may be involved in the development of certain endothelial and vascular abnormalities and may even participate in the generation of SSc-specific autoantibodies. Collectively, these observations suggest NOX4 as a novel therapeutic target for SSc.

Peripheral blood leucocyte telomere length is associated with progression of interstitial lung disease in systemic sclerosis

BackgroundPeripheral blood leucocyte telomere length (PBL-TL) is associated with outcomes in patients with idiopathic pulmonary fibrosis. Whether PBL-TL is associated with progression of systemic sclerosis-associated interstitial lung disease (SSc-ILD) is...

Autoantibody profiles delineate distinct subsets of scleromyositis.

Scleromyositis remains incompletely characterized owing in part to its heterogeneity. The purpose of this study was to explore the role of autoantibody profiles to define subsets of scleromyositis. Subjects with scleromyositis from a prospective cohort were divided into three groups based on autoantibody profiles: subjects with SSc-specific autoantibodies (anti-centromere, -topoisomerase 1, -RNA polymerase III, -Th/To, -fibrillarin), subjects with SSc-overlap autoantibodies (anti-PM/Scl, -U1RNP, -Ku) and subjects without SSc-related autoantibodies. Clinical features, laboratory tests and histopathological findings were retrieved and compared between groups. Of 42 scleromyositis subjects (79% female, mean age at diagnosis 55 years, mean disease duration 3.5 years), 8 (19%) subjects had SSc-specific autoantibodies, 14 (33%) SSc-overlap autoantibodies and 20 (48%) had no SSc-related autoantibodies. One-third had no skin involvement, a finding more frequent in the SSc-overlap subjects and those without SSc-related autoantibodies. Proximal and distal weakness was common and head drop/bent spine was found in 50% of the SSc-specific and 35% of the subjects without SSc-related autoantibodies. Of note, the group without SSc-related autoantibodies had the only cases of severe cardiac systolic dysfunction (n = 1) and scleroderma renal crisis (n = 1), as well as three out of the four cancers and three out of the four deaths. In this carefully phenotyped series of scleromyositis subjects, absence of SSc-related autoantibodies was common and associated with distinct features and poor prognosis. Future studies are needed to validate these results and possibly identify novel autoantibodies or other biomarkers associated with scleromyositis.

Systematic Analysis of the Literature in Search of Defining Systemic Sclerosis Subsets.

Systemic sclerosis (SSc) is a multisystem disease with heterogeneity in presentation and prognosis.An international collaboration to develop new SSc subset criteria is underway. Our objectives were to identify systems of SSc subset classification and synthesize novel concepts to inform development of new criteria. Medline, Cochrane MEDLINE, the Cumulative Index to Nursing and Allied Health Literature, EMBASE, and Web of Science were searched from their inceptions to December 2019 for studies related to SSc subclassification, limited to humans and without language or sample size restrictions. Of 5686 citations, 102 studies reported original data on SSc subsets. Subset classification systems relied on extent of skin involvement and/or SSc-specific autoantibodies (n = 61), nailfold capillary patterns (n = 29), and molecular, genomic, and cellular patterns (n = 12). While some systems of subset classification confer prognostic value for clinical phenotype, severity, and mortality, only subsetting by gene expression signatures in tissue samples has been associated with response to therapy. Subsetting on extent of skin involvement remains important. Novel disease attributes including SSc-specific autoantibodies, nailfold capillary patterns, and tissue gene expression signatures have been proposed as innovative means of SSc subsetting.