Early Diffuse Systemic Sclerosis Research Articles

P147 M2 macrophage associated fibrosis in early stage systemic sclerosis: an update on plasma biomarkers

Abstract Background/Aims Systemic sclerosis is an autoimmune connective tissue disease characterised by vasculopathy and fibrosis. The CCN family of matricellular proteins have a regulatory role in inflammation and fibrosis. CD206, an M2 macrophage surface marker, is cleaved by metalloproteases to release soluble form of CD206; this acts as an active disease marker in systemic sclerosis. We investigated the profile of CCN2 and CCN3 in the presence of soluble CD206 (sCD206) in patients with early and late stage diffuse systemic sclerosis (dcSSc). Methods Patients with a diagnosis of dcSSc at the UCL Centre for Rheumatology and Connective Tissue Diseases were recruited. Informed consent was obtained from patients and healthy controls (HC). Blood samples were taken from which plasma was isolated and stored at -80 °C prior to assay. Expression of CCN2, CCN3, and sCD206 was measured in these plasma samples by ELISA. Study participants were categorised into healthy controls (n = 20), early stage dcSSc (n = 20) and late dcSSc (n = 20), with early stage defined as the blood sample taken within two years since diagnosis, and late stage defined as over five years since diagnosis. Results Plasma CCN2, CCN3 and sCD206 levels were significantly higher in early dcSSc patients, when compared to HC. CCN2 was raised in early dcSSc patients (early dcSSc mean 20,221pg/ml, SD 16,503, p < 0.05) with concentration in late disease matching that of HC (late dcSSc 12,893pg/ml, HC 11,289pg/ml). CCN3 was significantly higher in early and late disease when compared to HC (early mean 16,526pg/ml, late 12,838pg/ml, HC 4,201pg/ml, p < 0.05). sCD206 levels were higher in early dcSSc (mean 5356pg/ml, SD 3154, p < 0.05), with there being no significance between levels in late dcSSc (mean 4184pg/ml, SD 3900, p > 0.05) and HC (mean 3319pg/ml, SD 1925). CCN2 expression was higher compared to that of CCN3 in early disease, with CCN2:CCN3 ratio elevated in early dcSSc (mean 3.17, SD 8.26) compared to late dcSSc (mean 1.26, SD 0.99) and HC. Conclusion This investigation demonstrates that upregulation of CCN2 and CCN3 expression has a regulatory role in fibrosis in early stage dcSSc. These biomarkers of M2 macrophage associated fibrosis are to be correlated with their clinical phenotype and have potential for a role in targeted treatment of systemic sclerosis. Disclosure L.A. Leeves: None. Z. Kannan: None. Y. Ali: None. L. Pan: None. T. Malley: None. D. Abraham: None. A. Leask: None. B. Riser: None. B. Ahmed Abdi: None. R.J. Stratton: None.

Flemish network on rare connective tissue diseases (CTD): patient pathways in systemic sclerosis. First steps taken

ABSTRACT Despite the low prevalence of each rare disease, the total burden is high. Patients with rare diseases encounter numerous barriers, including delayed diagnosis and limited access to high-quality treatments. In order to tackle these challenges, the European Commission launched the European Reference Networks (ERNs), cross-border networks of healthcare providers and patients representatives. In parallel, the aims and structure of these ERNs were translated at the federal and regional levels, resulting in the creation of the Flemish Network of Rare Diseases. In line with the mission of the ERNs and to ensure equal access to care, we describe as first patient pathways for systemic sclerosis (SSc), as a pilot model for other rare connective and musculoskeletal diseases. Consensus was reached on following key messages: 1. Patients with SSc should have multidisciplinary clinical and investigational evaluations in a tertiary reference expert centre at baseline, and subsequently every three to 5 years. Intermediately, a yearly clinical evaluation should be provided in the reference centre, whilst SSc technical evaluations are permissionably executed in a centre that follows SSc-specific clinical practice guidelines. In between, monitoring can take place in secondary care units, under the condition that qualitative examinations and care including interactive multidisciplinary consultations can be provided. 2. Patients with early diffuse cutaneous SSc, (progressive) interstitial lung disease and/or pulmonary arterial hypertension should undergo regular evaluations in specialised tertiary care reference institutions. 3. Monitoring of patients with progressive interstitial lung disease and/or pulmonary (arterial) hypertension will be done in agreement with experts of ERN LUNG.

Outcomes in progressive systemic sclerosis treated with autologous hematopoietic stem cell transplantation compared with combination therapy.

Autologous hematopoietic stem cell transplantation (AHSCT) has been shown to improve long-term survival for early diffuse progressive SSc compared with CYC. CYC, however, does not provide a long-term benefit in SSc. The combination of MMF and rituximab is a potent alternative regimen. We aimed to retrospectively compare the outcomes of SSc patients who underwent AHSCT to patients who met the eligibility criteria for AHSCT but received upfront combination therapy with MMF and rituximab. Repeated assessments of modified Rodnan Skin Score (mRSS), forced vital capacity (FVC), and diffusing capacity (DLCO) values were conducted. Clinical improvement was defined as an mRSS decrease >25% or an FVC increase >10%. Event-free survival (EFS) was defined in the absence of persistent major organ failure or death. Twenty-one SSc patients in the combination therapy group were compared with 16 in the AHSCT group. Age, sex and disease duration were similar between the two groups. Clinical improvement at 12 months was seen in 18 (86%) patients in the combination group compared with 13 (81%) in the AHSCT group (P = 0.7). The hazard ratio for EFS at 24 months favoured the combination group (HR = 0.09, P = 0.04). During follow-up, both groups exhibited a significant and comparable reduction in mRSS and an increase in FVC values at each time interval up to 24 months. MMF and rituximab compared with AHSCT in SSc patients eligible for AHSCT resulted in similar skin and lung clinical improvement with a better safety profile at 24 months.

Elevated interleukin-11 in systemic sclerosis and role in disease pathogenesis.

Systemic sclerosis (SSc) is an autoimmune connective tissue disease in which there is elevated inflammation, aberrant cytokine expression, and subsequent fibrosis. Interleukin-11 (IL-11) is a recently described profibrotic cytokine that can mediate fibrosis in the heart, lungs, and skin and is upregulated by transforming Growth Factor-β (TGF-β1). The objective of this study was to quantify the serum levels of IL-11 in early diffuse SSc patients. Also, if IL-11 could regulate the alarmin IL-33 in dermal fibroblasts was quantified. Early diffuse SSc patient sera was isolated and IL-11 was quantified by specific commercial ELISA compared to healthy control (n = 17). Healthy dermal fibroblasts were cultured in vitro and then serum starved and incubated with or without recombinant IL-11. At specific early and late time points the supernatant was quantified for the alarmin IL-33 by specific ELISA. In early diffuse SSc patients it was demonstrated that they have elevated IL-11 in their sera. In a subgroup of SSc patients with interstitial lung disease (ILD) this elevation was particularly pronounced compared to those devoid of fibrotic lung disease. In vitro incubation of healthy dermal fibroblasts led to a significant induction of IL-33 cytokine release into the cell media. IL-11 is a profibrotic cytokine that is elevated in early diffuse SSc and is particularly elevated in those with ILD. This suggests that IL-11 could be a possible biomarker of ILD in SSc. It was also found that IL-11 led to release of the cytokine alarmin IL-33 in fibroblasts at earlier time points but not late time points, suggesting early stimulation elicits an inflammatory response in the local microenvironment but prolonged stimulation leads to fibrosis.

Native T1 mapping in early diffuse and limited systemic sclerosis, and its association with diastolic function

BackgroundSystemic sclerosis (SSc) is divided into diffuse and limited cutaneous SSc (dcSSc and lcSSc). The dcSSc subtype has more severe internal organ damage. This study aimed to assess whether cardiovascular magnetic resonance (CMR) parametric mapping could detect early cardiac involvement and evaluate differences between these two subtypes. MethodsEighty SSc patients (37 dcSSc and 43 lcSSc) underwent CMR at 3.0 T (Philips Healthcare, Best, The Netherlands) in our hospital between July 2018 and July 2021. We analyzed myocardial damage by CMR parametric mapping and compared it with clinical data. ResultsThe median duration of the disease was 10.2 months. The left ventricular ejection fraction was preserved in both groups. DcSSc had significantly higher native T1 (1333.4 ± 71.2 ms vs. 1295.0 ± 42.7 ms, p = 0.006) and extracellular volume fraction (32.6 ± 4.1 % vs. 30.3 ± 4.0 %, p = 0.018) in the mid-ventricular septum as compared to lcSSc, although there were no differences in T2 values. Native T1 values were positively correlated with the E/e’ ratio and left atrial volume indices evaluated by transthoracic echocardiography in overall SSc and dcSSc, but not in lcSSc. Logistic regression analysis revealed that native T1 was an independent predictor of left ventricular diastolic dysfunction in SSc patients (odds ratio, 1.194; 95 % confidence interval, 1.021–1.396; p = 0.026). Native T1 was higher in SSc patients with progressive skin lesions. Additionally, there were positive correlations between brain natriuretic peptide, New York Heart Association functional classification, and native T1. ConclusionsCMR parametric mapping is a useful tool for detecting myocardial changes. Native T1 was the most sensitive parameter for identifying diffuse myocardial changes in the early stages of SSc and was associated with left ventricular diastolic function. DcSSc had more severe myocardial involvement than lcSSc; therefore, the use of CMR parametric mapping may aid in its prediction.

State-of-the-art evidence in the treatment of systemic sclerosis.

Systemic sclerosis (SSc) is a rare autoimmune connective tissue disease with multi-organ involvement, fibrosis and vasculopathy. Treatment in SSc, including early diffuse cutaneous SSc (dcSSc) and the use of organ-specific therapies, has improved, as evident from randomized clinical trials. Treatments for early dcSSc include immunosuppressive agents such as mycophenolate mofetil, methotrexate, cyclophosphamide, rituximab and tocilizumab. Patients with rapidly progressive early dcSSc might be eligible for autologous haematopoietic stem cell transplantation, which can improve survival. Morbidity from interstitial lung disease and pulmonary arterial hypertension is improving with the use of proven therapies. Mycophenolate mofetil has surpassed cyclophosphamide as the initial treatment for SSc-interstitial lung disease. Nintedanib and possibly perfinidone can be considered in SSc pulmonary fibrosis. Pulmonary arterial hypertension is frequently treated with initial combination therapy (for example, with phosphodiesterase5 inhibitors and endothelin receptor antagonists) and, if necessary, the addition of a prostacyclin analogue. Raynaud phenomenon and digital ulcers are treated with dihydropyridine calcium channel blockers (especially nifedipine), then phosphodiesterase5 inhibitors or intravenous iloprost. Bosentan can reduce the development of new digital ulcers. Trial data for other manifestations are mostly lacking. Research is needed to develop targeted and highly effective treatments, best practices for organ-specific screening and early intervention, and sensitive outcome measurements.

A data-driven approach finds RNA polymerase III antibody and tendon friction rubs as enrichment tools for early diffuse scleroderma trials.

Clinical trials in early diffuse SSc have consistently shown a placebo group response with a declining modified Rodnan skin score (mRSS), with negative outcomes. Our objective was to identify strategies using clinical characteristics or laboratory values to improve trial design. We identified early diffuse SSc patients first seen at the University of Pittsburgh from 1980-2015. Eligible patients had ≥3 visits, with at least two mRSS scores within the first year of follow-up. We performed Kaplan-Meier analyses, group-based trajectory analysis of mRSS scores, followed by multivariable regression analysis and classification tree analysis. We applied the results to the abatacept in early diffuse systemic sclerosis (ASSET) trial outcome data. We identified 403 patients with <18 months, and 514 with <36 months disease duration. The median number of mRSS follow-up scores was 14 (interquartile range 8, 25). All methodologic approaches identified skin thickness progression rate, RNA polymerase III (RNAP3) antibody positivity and presence of tendon friction rubs (TFR) as predictors of mRSS trajectory over 5 years of follow-up, and thereby as potential enrichment variables. When applied to the ASSET data, adjustment for both RNAP3 and TFR demonstrated reduction of the placebo mRSS response, particularly at 6 months. A significant difference in the ACR Composite Response Index in Systemic Sclerosis (CRISS) score was found with adjustment by RNAP3 at 6 months, and TFR or RNAP3 at 12 months. Adjustment for both RNAP3 and TFR predicts mRSS trajectory and diminished the mRSS decline in ASSET placebo group, and identified significant differences in CRISS. RNAP3, particularly, is a stratification or enrichment approach to improve early diffuse SSc trial design.

Interleukin-36α is elevated in diffuse systemic sclerosis and may potentiate fibrosis.

Systemic sclerosis (SSc) is an autoimmune prototypical connective tissues disease that results in alterations in vasculature, inflammation and fibrosis of the skin. Interleukin-1 family cytokines has been implicated in the disease including IL-1. IL-36α is an IL-1 family member that is clearly implicated in psoriatic skin disease but its role in systemic sclerosis disease is not clear. The aim of this work is to evaluate the levels and role of IL-36α in systemic sclerosis. Early diffuse SSc patients sera was isolated along with healthy controls and IL-36 levels quantified by ELISA. In vitro analysis was also undertaken with primary dermal fibroblasts with recombinant IL-36α and keratinocyte cells were also incubated with IL-36α. Cytokines were measured by ELISA. Serum IL-36 was significantly elevated compared to healthy controls. Elevated neutrophil elastase was also elevated in the matched sera. IL-36 was not directly pro-fibrotic in dermal fibroblasts but did induce pro-inflammatory cytokines that were dependant on the MAPK pathway for their release. IL-36α also led to release of CCL20 and CCL2 in keratinocytes which may potentiate fibrosis. IL-36α is elevated in SSc serum and whilst not directly pro-fibrotic it may through keratinocytes, potentiate fibrosis through keratinocyte-immune fibroblast cross-talk.

POS0069 LONGITUDINAL CHANGES ON QUANTITATIVE CHEST HIGH-RESOLUTION COMPUTED TOMOGRAPHY IN EARLY DIFFUSE SYSTEMIC SCLEROSIS-RELATED INTERSTITIAL LUNG DISEASE AFTER AUTOLOGOUS HEMATOPOIETIC STEM CELL TRANSPLANTATION.

BackgroundSince Burt et al. first demonstrated in the ASSIST trial (1) that lung disease high-resolution computed tomography (HRCT) volumetric measurement decreased in autologous hematopoietic stem cell transplantation (aHSCT) recipients and increased in controls receiving cyclophosphamide iv one year after starting treatment, limited data have been reported concerning the evolution of Systemic Sclerosis-Interstitial Lund disease (SSc-ILD) since and its relationship with the evolution of esophageal volume is unknown.ObjectivesTo evaluate High-Resolution Computed Computed Tomography (HRCT) interstitial lung disease (ILD) and esophageal involvement in early diffuse systemic sclerosis (dSSc)-patients before and after autologous Hematopoietic Stem Cell Transplantation (aHSCT).MethodsOverall chest HRCT, lung function and skin score changes were evaluated in 33 consecutive dSSc-patients before and after aHSCT during yearly routine follow-up between January 2000 and september 2016.Two independent radiologists blindly assessed the ILD extent using semi-quantitative Goh and Wells method (2), the widest esophageal diameter (WED) and the esophageal volume (EV) on HRCT. Patients were retrospectively classified as radiological responders or non-responders at 24 months after aHSCT according to the stability or a 5% or more decrease of HRCT ILD extent. Two by two time points comparisons after versus before aHSCT were performed using linear regressions. Survival rates were assessed for all patients by Kaplan-Meier method.ResultsTwenty-four months after aHSCT, HRCT median [IQR] ILD (-2 [-10.3; 0] points, p=0.0002) and ground-grass opacities (-2.1 [-8.3; 0] points, p=0.02) extent scores had improved, with 18 patients radiological responders (probability of response 0.78, 95% CI (0.58;0.90), whereas median WED (from 24.5 [18; 29] to 28 [19; 33] mm; p= 0.005) and EV (from 19 [13; 33] to 30 [13; 58] mm3, p=0.01) increased significantly. Kaplan-Meier analyses showed a trend towards better 5 years survival rates (100% versus 60%; HR 0.23 95%CI 0.03 to 1.62, P = 0.11) among radiological responders versus non-responders at 24 months.ConclusionReal-world data analysis confirmed significant HRCT SSc-ILD improvement 24 months after aHSCT, although esophageal dilatation worsened requiring specific attention.

Advances in the Treatment of Systemic Sclerosis

Although systemic sclerosis (SSc) is currently incurable, there have been recent advances in treatment. This review article begins by providing a brief background to SSc in terms of disease subtyping and autoantibodies, because both predict disease trajectory and help clinicians to select appropriate monitoring and treatment protocols. Broad principles of management are then described: ‘disease-modifying’ therapies and therapies directed at reducing disease burden and/or progression of SSc-related digital vascular disease and of internal organ involvement. Next, advances in the management of digital vasculopathy, pulmonary arterial hypertension (PAH), interstitial lung disease (ILD) and early diffuse cutaneous SSc are discussed in turn, for example: (a) increased use of phosphodiesterase inhibitors and endothelin receptor antagonists for digital vasculopathy; (b) early recognition and treatment of PAH, including with combination therapies; (c) increased use of mycophenolate mofetil and of nintedanib in ILD; and (d) immunosuppression now as standard practice in early diffuse cutaneous SSc, and autologous haematopoietic stem cell transplantation for highly selected patients with progressive diffuse disease. Finally, future challenges are discussed, including ensuring that all patients with SSc are monitored and treated according to best practice guidelines, and whenever possible giving patients the opportunity to participate in clinical trials.

Large-scale analysis of longitudinal skin gene expression in systemic sclerosis reveals relationships of immune cell and fibroblast activity with skin thickness and a trend towards normalisation over time

ObjectivesDetermine relationships between skin gene expression and systemic sclerosis (SSc) clinical disease features, and changes in skin gene expression over time.MethodsA total of 339 forearm skin biopsies were obtained from...

Endothelial CCR6 expression due to FLI1 deficiency contributes to vasculopathy associated with systemic sclerosis

BackgroundWe have recently demonstrated that serum CCL20 levels positively correlate with mean pulmonary arterial pressure in patients with systemic sclerosis (SSc). Considering a proangiogenic effect of CCL20 on endothelial cells via CCR6, the CCL20/CCR6 axis may contribute to the development of SSc vasculopathy. Therefore, we explored this hypothesis using clinical samples, cultured cells, and murine SSc models.MethodsThe expression levels of CCL20 and CCR6 in the skin, mRNA levels of target genes, and the binding of transcription factor FLI1 to the target gene promoter were evaluated by immunostaining, quantitative reverse transcription PCR, and chromatin immunoprecipitation, respectively. Vascular permeability was evaluated by Evans blue dye injection in bleomycin-treated mice. Angiogenic activity of endothelial cells was assessed by in vitro angiogenesis assay.ResultsCCL20 expression was significantly elevated in dermal fibroblasts of patients with early diffuse cutaneous SSc, while CCR6 was significantly up-regulated in dermal small vessels of SSc patients irrespective of disease subtypes and disease duration. In human dermal microvascular endothelial cells, FLI1 siRNA induced the expression of CCR6, but not CCL20, and FLI1 bound to the CCR6 promoter. Importantly, vascular permeability, a representative SSc-like vascular feature of bleomycin-treated mice, was attenuated by Ccr6 siRNA treatment, and CCR6 siRNA suppressed the angiogenic activity of human dermal microvascular endothelial cells assayed by in vitro tube formation.ConclusionsThe increased expression of endothelial CCR6 due to FLI1 deficiency may contribute to the development of SSc vasculopathy.

Circulating Gremlin-1 is elevated in systemic sclerosis patients.

Introduction:Systemic sclerosis is an autoimmune connective tissue disease in which there is activation of the immune system, vascular disease and fibrosis. Activation of quiescent fibroblasts to myofibroblasts is key to disease pathogenesis. Gremlin-1 is a bone morphogenetic protein antagonist which is important in development and we recently reported in skin fibrosis. The aim of this study was to determine the serum circulating levels of Gremlin-1 in early diffuse systemic sclerosis.Methods:Twenty-one early diffuse systemic sclerosis patients (less than 2 years from first non-Raynaud’s symptom) were included and age and sex-matched healthy controls. Serum was isolated from blood and measured with a specific enzyme-linked immunoassay for Gremlin-1. Clinical variables were also measured.Results:Significantly elevated Gremlin-1 was found in sera of early diffuse systemic sclerosis patients (p < 0.001). In patients with interstitial lung disease, this compared to systemic sclerosis without evidence of interstitial lung disease, Gremlin-1 was significantly elevated (p < 0.0007). A correlation was found between circulating Gremlin-1 and modified Rodnan Skin Score, albeit weak.Discussion:In early diffuse systemic sclerosis patients, elevated Gremlin-1 is found in serum. This is particularly prominent in systemic sclerosis–associated interstitial lung disease. This suggests that Gremlin-1 may be a biomarker for systemic sclerosis interstitial lung disease.

Sensitivity to change of joint count composite indices in 72 patients with systemic sclerosis.

We validated the responsiveness of joint count composite indices (JCCIs) in 72 patients with systemic sclerosis (SSc). Changes in Disease Activity Score of 28 Joints using ESR and CRP (DAS28-ESR, DAS28-CRP), Simplified Disease Activity Index (SDAI) and the Clinical Disease Activity Index (CDAI) were evaluated in a one-year follow-up study. Charts of patients including swollen/tender joint counts, laboratory signs of inflammation, and visual analogue scales referring to disease activity, severity and pain were also blindly categorized by two rheumatologists as improved, unchanged or deteriorated. These categories were used as references for the determination of effect size (ES) and standardised response mean (SRM). Articular inflammation improved in 15, deteriorated in 12, and remained unchanged in 45 (63%) patients with SSc based on the concordant opinion of two clinical investigators. All four JCCIs were sensitive to changes (ES>1; SRM>1). The correlation between changes in JCCIs and the physicians' evaluation was high (r >0.68; p<0.001). Arthritis was predominantly prone to change in patients with high JCCIs, impaired functional status, anti-RNA polymerase III antibodies and patients on DMARD therapy. Synovitis was more prevalent in patients with early diffuse SSc, and tended to improve during the follow-up. All four JCCIs were sensitive to changes, if tender/swollen joints were present at baseline. Articular inflammation was most prone to change in patients with high JCCIs, impaired functional status and already decreased health-related quality of life at baseline.

Clinical characteristics, visceral involvement, and mortality in at-risk or early diffuse systemic sclerosis: a longitudinal analysis of an observational prospective multicenter US cohort

BackgroundEarly diffuse cutaneous systemic sclerosis (dcSSc) has the highest case fatality among rheumatic diseases. We report baseline characteristics, current immunosuppressive therapies, progression of skin and internal organ involvement, and mortality in a multicenter prospective cohort from the United States (US) of America.MethodsWe performed a longitudinal analysis of participants from 12 US centers, from April 2012 to July 2020. All participants had early dcSSc or were at-risk for dcSSc, with ≤2 years since the first non-Raynaud’s phenomenon (RP) symptom.ResultsThree hundred one patients were included with a baseline median disease duration of 1.2 years since RP and a mean modified skin score of 21.1 units. At baseline, 263 (87.3%) had definite dcSSc and 38 (12.7%) were classified as at-risk; 112 (49.6%) patients were positive for anti-RNA polymerase III antibodies. The median follow-up duration was 24.5 months (IQR = 10.3–40.7 months). One hundred ninety (63.1%) participants were treated with an immunosuppressive therapy, of which mycophenolate mofetil was most used at baseline and follow-up. Of 38 who were classified as at-risk at baseline, 27 (71%) went on to develop dcSSc; these patients were characterized by higher baseline mean HAQ-DI (0.8 versus 0.4, p = 0.05) and higher baseline mRSS (8.8 versus 4.4, p < 0.01) in comparison with those who remained as limited cutaneous SSc. In the overall cohort, 48 participants (21.1%) had clinically significant worsening of skin fibrosis, mainly occurring in the first year of follow-up; 41 (23.3%) had an absolute forced vital capacity decline of ≥10%. Twenty participants (6.6%) died, of which 18 died in the first 3 years of follow-up. Cardiac involvement (33.3%), gastrointestinal dysmotility (22.2%), and progressive interstitial lung disease (ILD) (16.7%) were the main causes of death.ConclusionThis US cohort highlights the management of early SSc in the current era, demonstrating progression of skin and lung involvement despite immunosuppressive therapy and high mortality due to cardiac involvement.

Analysis of PI3K Pathway Associated Molecules Reveals Dysregulated Innate and Adaptive Functions of B Cells in Early Diffuse Cutaneous Systemic Sclerosis.

B cell activation is an early event in the development of systemic sclerosis (SSc). The classical activation of B cells downstream of the B-cell receptor (BCR) involves the phosphatidylinositol-3 kinase (PI3K) pathway that integrates the effects of multiple co-stimulatory receptors. Our analysis of PI3K pathway associated molecules in peripheral blood B cells of early diffuse cutaneous SSc (dcSSc) patients showed altered mRNA expression of Toll-like receptor (TLR) homolog CD180, TLR4, complement component 3, IL-4 receptor and secreted phosphoprotein 1 (SPP1). Parallel to this, we found elevated basal SPP1 secretion in dcSSc B cells, but, with BCR + IL-4 receptor co-stimulation, we could not induce further secretion. CD180 stimulation alone resulted in NF-κB activation in more B cells than CD180 + BCR co-stimulation both in dcSSc and healthy control (HC), but the co-engagement increased the phosphorylation of NF-κB only in dcSSc B cells. Additionally, in contrast with HC B cells, the lower basal production of IL-10 by dcSSc B cells could not be elevated with CD180 stimulation. Furthermore, activation via CD180 increased the percentage of CD86+ switched memory (CD27+IgD−) B cells in dcSSc compared to HC. Our results suggest that alternative B cell activation and CD180 dysfunction cause imbalance of regulatory mechanisms in dcSSc B cells.

IL11 is elevated in systemic sclerosis and IL11-dependent ERK signalling underlies TGFβ-mediated activation of dermal fibroblasts.

ObjectivesInterleukin 11 (IL11) is highly upregulated in skin and lung fibroblasts from patients with systemic sclerosis (SSc). Here we tested whether IL11 is mechanistically linked with activation of human dermal fibroblasts (HDFs) from patients with SSc or controls.MethodsWe measured serum IL11 levels in volunteers and patients with early diffuse SSc and manipulated IL11 signalling in HDFs using gain- and loss-of-function approaches that we combined with molecular and cellular phenotyping.ResultsIn patients with SSc, serum IL11 levels are elevated as compared with healthy controls. All transforming growth factor beta (TGFβ) isoforms induced IL11 secretion from HDFs, which highly express IL11 receptor α-subunit and the glycoprotein 130 (gp130) co-receptor, suggestive of an autocrine loop of IL11 activity in HDFs. IL11 stimulated ERK activation in HDFs and resulted in HDF-to-myofibroblast transformation and extracellular matrix secretion. The pro-fibrotic action of IL11 in HDFs appeared unrelated to STAT3 activity, independent of TGFβ upregulation and was not associated with phosphorylation of SMAD2/3. Inhibition of IL11 signalling using either a neutralizing antibody against IL11 or siRNA against IL11RA reduced TGFβ-induced HDF proliferation, matrix production and cell migration, which was phenocopied by pharmacological inhibition of ERK.ConclusionsThese data reveal that autocrine IL11-dependent ERK activity alone or downstream of TGFβ stimulation promotes fibrosis phenotypes in dermal fibroblasts and suggest IL11 as a potential therapeutic target in SSc.

Defining the optimal disease duration of early diffuse systemic sclerosis for clinical trial design.

Clinical trials in early diffuse cutaneous systemic sclerosis (SSc) using the modified Rodnan skin score (mRSS) as the primary outcome measure have most often been negative. We wanted to assess how the definition of disease onset (first SSc manifestation vs first non-Raynaud manifestation) and varying lengths of disease duration at trial entry as an inclusion criteria functioned. Our objective was to optimize trial inclusion criteria. We used the prospective, observational University of Pittsburgh Scleroderma Cohort to identify early diffuse SSc patients first evaluated between 1980 and 2015. All had <3 years from first SSc (n = 481) or first non-Raynaud manifestation (n = 514) and three or more mRSS scores. We used descriptive, survival and group-based trajectory analyses to compare the different definitions of disease onset and disease duration as inclusion criteria for clinical trials. There was no appreciable difference between using first SSc manifestation compared with first non-Raynaud manifestation as the definition of disease onset. Compared with other disease durations, <18 months of disease had >70% of patients fitting into trajectories with worsening cutaneous disease over 6 months of follow-up. Longer disease durations demonstrated the majority of patients with trajectories showing an improvement in mRSS (regression to the mean) over 6 months. Regardless of whether the first SSc or first non-Raynaud manifestation is used to define disease onset, duration of <18 months at enrolment is preferable. A longer disease duration criterion more frequently results in regression to the mean of the mRSS score, and likely contributes to negative trial outcomes.

Lymphocyte subset abnormalities in early diffuse cutaneous systemic sclerosis

BackgroundAbnormalities in lymphocyte surface markers and functions have been described in systemic sclerosis (SSc), but conflicting results abound, and these studies often examined patients with heterogeneous disease duration, severity, clinical phenotype, and concurrent immunosuppressive agents. We studied a clinically homogeneous group of early diffuse cutaneous SSc patients not exposed to immunosuppressive drugs who were enrolled in a clinical trial and compared their immune parameters to healthy control subjects.MethodsLymphocyte subsets were enumerated by multi-parameter flow cytometry of peripheral blood mononuclear cells at baseline visit. Production of the cytokines IL-4 and IL-17 was measured by intracellular flow cytometry following T cell activation.ResultsSSc patients had increased percentages of CD4+ T cells but lower percentages of CD8+ T cells versus controls. The CD28-negative population was expanded in SSc, in the CD4 subset. Striking expansion of CD319+ T cells was noted among the CD4+ cells, in which they were barely detectable in healthy subjects. Frequencies of IL-4 producing cells did not differ between SSc and controls, but expansion of IL-17 producing cells was observed in SSc. A higher proportion of CD319+ cells produced cytokines, compared to other CD4+ cells. Numbers of activated T cells, regulatory T cells, and B cells were similar in SSc and control groups. Circulating follicular helper but not peripheral helper T cells were slightly expanded in SSc.ConclusionIn this carefully selected group of early diffuse cutaneous SSc patients, analysis of immune cell parameters has identified abnormalities that likely reflect disease pathogenesis and that are candidate biomarkers for sub-classification and targeted treatment. The CD4+CD319+ (SLAM-F7+) cells are cytotoxic and oligoclonal, were recently shown to be a dominant T cell population in perivascular lymphocytic infiltrates in SSc skin, actively secrete cytokines, and are emerging as a target for novel treatments of SSc.

Frontiers in translational systemic sclerosis research: A focus on the unmet 'cutaneous' clinical needs (Viewpoint).

This viewpoint considers four cutaneous unmet clinical needs of patients with systemic sclerosis (SSc), namely the rapidly progressive skin thickening (scleroderma) which occurs early on in diffuse cutaneous disease; digital (finger and toe) ulcers; calcinosis; and cutaneous telangiectases. All four problems cause pain, disability and/or disfigurement, all impact on quality of life, and for each, we require effective treatments. For each unmet need, we give a brief description of the clinical problem (including clinical burden), pathophysiology and current treatment, followed by a personal viewpoint of the key questions which research must address. For the painful, debilitating skin thickening of early diffuse cutaneous SSc, studies are required to decide whether corticosteroids are effective and safe (current opinion is divided) and whether phototherapy approaches have a role. Also, we need to develop and validate reliable outcome measures for clinical trials of promising new therapies: these could be composite indices, novel non-invasive imaging methods and patient-reported outcome measures, possibly in combination as they provide complementary information. For digital ulcers, again we require validated outcome measures for clinical trials. We also need to explore local (including topical) treatments, which are free from systemic adverse effects, and preventative strategies for high-risk patients. For calcinosis, we need to better understand pathophysiology, to validate outcome measures and to develop topical treatments. For telangiectases, we need to "use" these highly accessible lesions to help unravel the vascular pathophysiology of SSc and explore their different properties as potential biomarkers.