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

Absence of Scleroderma pattern at nail fold capillaroscopy valuable in the exclusion of Scleroderma in unselected patients with Raynaud's Phenomenon

Background: To report the predictive value of nail-fold capillaroscopy (NFC) patterns of vasculopathy for systemic sclerosis (Scleroderma; SSc) in an unselected cohort of patients with Raynaud's phenomenon (RP). Methods: Patients referred to a tertiary SSc clinic with RP were evaluated by light/video-NFC. Clinical diagnosis, details and serology were recorded. Primary RP was defined as RP with no features of connective tissue disease (CTD)/antibody. NFC patterns were determined: normal, non-specific, 'early', 'active' or 'late' SSc patterns. Fulfilment of the VEDOSS or 2013 ACR/EULAR criteria for SSc was determined following NFC assessment. Results: Three hundred forty-seven patients were referred: mean (SD) age 47 (15.2) years. On clinical review, 54 (16 %) did not have RP, 69 (20 %) had primary RP, 52 (15 %) had SSc and 172 (50 %) had secondary RP. NFC SSc pattern was detected in 80 (23 %) patients; 37/52 with SSc, 30/172 with secondary RP, 9/69 with primary RP and 4/54 with no RP. For identifying patients who met either the VEDOSS or 2013 ACR/EULAR criteria for SSc, detection of a SSc NFC pattern had a sensitivity of 71 %, specificity 95 %, positive predictive value 84 % and negative predictive value 90 %. Conclusions: The absence of SSc NFC pattern in patients with RP or suspected CTD is very valuable in the exclusion of SSc

Survival and death causes in 251 systemic sclerosis patients from a single Italian center

Objective: To investigate survival in Italian systemic sclerosis (SSc) patients from a tertiary center, reporting death causes. Materials and methods: We analyzed the charts of 251 SSc patients prospectively enrolled in our Rheumatology Unit from 2000 to 2008. Baseline characteristics were recorded. In 2008 the vital status and the causes of death were assessed. Overall and subgroup survival were analyzed by the Kaplan-Meier method and the log-rank test. Results: In 2008, 82% of patients were alive, 8% were known to have died and 10% were lost to follow-up. Overall 5- and 8-year survival were 94.8% and 77.1%, respectively. Patients with an age greater than the median value of the cohort (χ2=4.4; p=0.036), diffuse cutaneous SSc (χ2=3.9; p=0.048), digital ulcers (χ2=6; p=0.015), articular (χ2=5.3; p=0.021), lung (χ2=5.6; p=0.018) and heart involvement (χ2=9.3; p=0.002) had a poorer survival than patients without these features. The majority of SSc-related deaths (60%) were secondary to interstitial lung disease and heart involvement (both 33.3%); 50% of non-SSc-related deaths were due to cancer. Conclusions: Our study reports an improvement in survival of Italian SSc patients during the last decade with respect to the previous ones. Moreover, a reduction in deaths from renal involvement and an increase in deaths from interstitial lung disease were recorded in Italian SSc patients. Our data are consistent with those from recent survival studies carried out on SSc patients from other geographic areas

Long non-coding RNA HOTAIR drives EZH2-dependent myofibroblast activation in systemic sclerosis through miRNA 34a-dependent activation of NOTCH

Background Systemic sclerosis (SSc) is characterised by autoimmune activation, tissue and vascular fibrosis in the skin and internal organs. Tissue fibrosis is driven by myofibroblasts, that are known to maintain their phenotype in vitro, which is associated with epigenetically driven trimethylation of lysine 27 of histone 3 (H3K27me3). Methods- Full-thickness skin biopsies were surgically obtained from the forearms of 12 adult patients with SSc of recent onset. Fibroblasts were isolated and cultured in monolayers and protein and RNA extracted. HOX transcript antisense RNA (HOTAIR) was expressed in healthy dermal fibroblasts by lentiviral induction employing a vector containing the specific sequence. Gamma secretase inhibitors were employed to block Notch signalling. Enhancer of zeste 2 (EZH2) was blocked with GSK126 inhibitor. Results- SSc myofibroblasts in vitro and SSc skin biopsies in vivo display high levels of HOTAIR, a scaffold long non-coding RNA known to direct the histone methyltransferase EZH2 to induce H3K27me3 in specific target genes. Overexpression of HOTAIR in dermal fibroblasts induced EZH2-dependent increase in collagen and α-SMA expression in vitro, as well as repression of miRNA-34A expression and consequent NOTCH pathway activation. Consistent with these findings, we show that SSc dermal fibroblast display decreased levels of miRNA-34a in vitro. Further, EZH2 inhibition rescued miRNA-34a levels and mitigated the profibrotic phenotype of both SSc and HOTAIR overexpressing fibroblasts in vitro. Conclusions- Our data indicate that the EZH2-dependent epigenetic phenotype of myofibroblasts is driven by HOTAIR and is linked to miRNA-34a repression-dependent activation of NOTCH signalling

SFRP4 Expression Is Linked to Immune-Driven Fibrotic Conditions, Correlates with Skin and Lung Fibrosis in SSc and a Potential EMT Biomarker

Secreted Frizzled Receptor Protein 4 (SFRP4) has been shown to be increased in Scleroderma (SSc). To determine its role in immune-driven fibrosis, we analysed SSc and sclerotic Chronic Graft Versus Host Disease (sclGVHD) biosamples; skin biopsies (n = 24) from chronic GVHD patients (8 with and 5 without sclGVHD), 8 from SSc and 3 healthy controls (HC) were analysed by immunofluorescence (IF) and SSc patient sera (n = 77) assessed by ELISA. Epithelial cell lines used for in vitro Epithelial-Mesenchymal-Transition (EMT) assays and analysed by Western Blot, RT-PCR and immunofluorescence. SclGVHD skin biopsies resembled pathologic features of SSc. IF of fibrotic skin biopsies indicated the major source of SFRP4 expression were dermal fibroblasts, melanocytes and vimentin positive/caveolin-1 negative cells in the basal layer of the epidermis. In vitro studies showed increased vimentin and SFRP4 expression accompanied with decreased caveolin-1 expression during TGFβ-induced EMT. Additionally, SFRP4 serum concentration correlated with severity of lung and skin fibrosis in SSc. In conclusion, SFRP4 expression is increased during skin fibrosis in two different immune-driven conditions, and during an in vitro EMT model. Its serum levels correlate with skin and lung fibrosis in SSc and may function as biomarker of EMT. Further studies are warranted to elucidate the role of SFRP4 in EMT within the pathogenesis of tissue fibrosi

MRI Digital Artery Volume Index (DAVIX) as a surrogate outcome measure of digital ulcer disease in patients with systemic sclerosis: a prospective cohort study

Background Vascular fibrosis is a key manifestation of systemic sclerosis that leads to the narrowing of small and medium arteries, causing vascular clinical manifestations including digital ulcers and pulmonary arterial hypertension. We investigated the potential of the MRI-based Digital Artery Volume Index (DAVIX) as a surrogate outcome measure of vascular fibrosis by using it to quantify and predict the burden of digital ulcer disease in patients with systemic sclerosis. Methods Two independent cohorts of patients participating in the prospective observational study STRIKE were consecutively enrolled from the Scleroderma Clinic of the Leeds Teaching Hospitals Trust, Leeds, UK. Eligible patients were aged 18 years or older and fulfilled the very early diagnosis of systemic sclerosis (VEDOSS) or the 2013 American College of Rheumatology (ACR)–European Alliance of Associations for Rheumatology (EULAR) systemic sclerosis classification criteria. DAVIX was calculated as the percentage mean of the ratio of digital artery volume to finger volume in the four fingers of the dominant hand. Data were collected at baseline and 12-month follow-up, and the primary outcome was the presence of digital ulcers at 12-month follow-up. Findings Between Feb 7, 2018, and April 11, 2022, we included 85 patients in the exploratory cohort and 150 in the validation cohort. In the exploratory cohort, the mean age was 54·5 years (SD 11·6), 75 (88%) of 85 patients were women, ten (12%) were men, and 69 (82%) were White. In the validation cohort, the mean age was 53·5 years (SD 13·8), 136 (91%) of 150 patients were women, 14 (9%) were men, and 127 (85%) were White. In the exploratory cohort, DAVIX was significantly lower in patients with previous or active digital ulcers (0·34% [IQR 0·16–0·69]) than in those without digital ulcer disease (0·65% [0·42–0·88]; p=0·015); this finding was substantiated in the validation cohort (0·43% [0·20–0·73] vs 0·73% [0·53–0·97]; p<0·0001). Patients who developed new digital ulcers during 12-month follow-up had a lower DAVIX (0·23% [0·10–0·66]) than those who did not (0·65% [0·45–0·91]; p=0·0039). DAVIX was negatively correlated with disease duration (r=−0·415; p<0·0001), the ratio of forced vital capacity to the diffusing capacity of the lungs for carbon monoxide (r=−0·334; p=0·0091), nailfold capillaroscopy pattern (r=−0·447; p<0·0001), and baseline modified Rodnan skin score (r=−0·305; p=0·014) and was positively correlated with the diffusing capacity of carbon monoxide (r=0·368; p=0·0041). DAVIX was negatively correlated with change in score on the Scleroderma Health Assessment Questionnaire-Disability Index (r=−0·308; p=0·024), Visual Analogue Scale (VAS) Raynaud's (r=−0·271; p=0·044), and VAS digital ulcers (r=−0·291; p=0·044). Interpretation DAVIX is a promising surrogate outcome measure of digital ulcer disease in patients with systemic sclerosis. The ability of DAVIX to non-invasively predict future digital ulcers and worsening of patient-reported outcomes could aid patient enrichment and stratification in clinical trials. Clinically, DAVIX could offer insights into the assessment of vascular activity. The sensitivity of DAVIX to change over time and with treatment will establish its value as an imaging outcome measure of vascular disease. Funding National Institute for Health Research Biomedical Research Centre and University of Leeds Industry Engagement Accelerator Fund