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

Cellular therapies in rheumatic and musculoskeletal diseases

A substantial proportion of patients diagnosed with rheumatologic and musculoskeletal diseases (RMDs) exhibit resistance to conventional therapies or experience recurrent symptoms. These diseases, which include autoimmune disorders such as multiple sclerosis, rheumatoid arthritis, and systemic lupus erythematosus, are marked by the presence of autoreactive B cells that play a critical role in their pathogenesis. The persistence of these autoreactive B cells within lymphatic organs and inflamed tissues impairs the effectiveness of B-cell-depleting monoclonal antibodies like rituximab. A promising therapeutic approach involves using T cells genetically engineered to express chimeric antigen receptors (CARs) that target specific antigens. This strategy has demonstrated efficacy in treating B-cell malignancies by achieving long-term depletion of malignant and normal B cells. Preliminary data from patients with RMDs, particularly those with lupus erythematosus and dermatomyositis, suggest that CAR T-cells targeting CD19 can induce rapid and sustained depletion of circulating B cells, leading to complete clinical and serological responses in cases that were previously unresponsive to conventional therapies. This review will provide an overview of the current state of preclinical and clinical studies on the use of CAR T-cells and other cellular therapies for RMDs. Additionally, it will explore potential future applications of these innovative treatment modalities for managing patients with refractory and recurrent manifestations of these diseases.

Porcupine inhibitors LGK-974 and ETC-159 inhibit Wnt/β-catenin signaling and result in inhibition of the fibrosis

OBJECTIVES

We evaluated potential therapeutic efficacy of LGK-974 and ETC-159 in fibrotic scleroderma cells.

METHODS

Primary scleroderma dermal fibroblast cells of mouse origin (SSc fibroblasts) and primary fibrotic lung fibroblast cells of human origin (CCL-191) were used in this study. PORCN inhibitors LGK-974 (S7143, 1 μM; Selleckchem, USA) and ETC-159 (S7143, 10 μM; Selleckchem, USA) were used. The possible therapeutic effects of LGK-974 and ETC-159 on scleroderma cells and fibrosis cells were examined. Cell viability experiments were performed for each substance, and the expression levels of WNT and fibrosis marker genes were determined by qPCR. Western blotting was also used to determine collagen, fibronectin and α-SMA protein markers.

RESULTS

This study showed that LGK-974 and ETC-159 probable protein-cysteine N-palmitoyltransferase porcupine (PORCN) inhibitors exert potent antifibrotic effects and reduce fibrosis by modulating the TGF-β signaling pathway in scleroderma cells. Using LGK-974 and ETC-159 PORCN inhibitors, either alone or in combination, can affect collagen deposition and fibrosis in patients with SSc.

CONCLUSIONS

LGK-974 and ETC-159 may be a possible long-term therapeutic target for scleroderma.

Mesenchymal Stromal Cell-Based Therapy: A Promising Approach for Autoimmune Diseases

Autoimmune diseases are characterized by immune dysregulation, resulting in aberrant reactivity of T cells and antibodies to self-antigens, leading to various patterns of inflammation and organ dysfunction. However, current therapeutic agents exhibit broad-spectrum activity and lack disease-specific selectivity, leading to enduring adverse effects, notably severe infections, and malignancies, and patients often fail to achieve the intended clinical goals. Mesenchymal stromal cells (MSCs) are multipotent stromal cells that can be easily derived from various tissues, such as adipose tissue, umbilical cords, Wharton's jelly, placenta, and dental tissues. MSCs offer advantages due to their immunomodulatory and anti-inflammatory abilities, low immunogenicity, and a high capacity for proliferation and multipotent differentiation, making them excellent candidates for cell-based treatment in autoimmune disorders. This review will cover preclinical studies and clinical trials involving MSCs in autoimmune diseases, as well as the primary challenges associated with the clinical application of MSC therapies and strategies for maximizing their therapeutic potential.

Endothelin-1 as a Candidate Biomarker of Systemic Sclerosis: A GRADE-Assessed Systematic Review and Meta-Analysis With Meta-Regression

Background

There is an ongoing search for novel biomarkers of vascular dysfunction, extent of fibrosis and organ involvement in systemic sclerosis (SSc).

Objectives

We critically appraised the studies investigating the circulating concentrations of endothelin-1 in SSc patients and healthy controls.

Design

This was a systematic review with meta-analysis.

Data sources and methods

We searched electronic databases (PubMed, Scopus, and Web of Science) from inception to 15 June 2024. We assessed the risk of bias and the certainty of evidence using the JBI Critical Appraisal Checklist and GRADE, respectively.

Results

Endothelin-1 concentrations were significantly higher in SSc patients than in controls (26 studies; standardised mean difference, SMD = 0.98, 95% CI 0.73-1.23, P < .001; moderate certainty of evidence). In SSc patients, there were no significant differences in endothelin-1 concentrations between those with limited and diffuse cutaneous SSc (10 studies; SMD = 0.32, 95% CI -0.07 to 0.71 P = .11; very low certainty), and with and without digital ulcers (5 studies; SMD = 0.82, 95% CI -0.06 to 1.69, P = .066; very low certainty), pulmonary arterial hypertension (7 studies; SMD = 0.22, 95% CI -0.01 to 0.45, P = .066; very low certainty) or interstitial lung disease (3 studies; SMD = 0.09, 95% CI -0.18 to 0.35, P = .51; very low certainty). There was limited evidence in SSc patients with different video capillaroscopy pattern and telangiectasias. Subgroup and meta-regression analyses showed significant associations between the effect size and geographical location (studies investigating SSc patients and controls), year of publication (studies investigating SSc patients with limited and diffuse cutaneous SSc), and biological matrix assessed (studies investigating SSc patients with and without digital ulcers).

Conclusion

The results of this systematic review and meta-analysis highlight the potential role of endothelin-1 as a candidate biomarker of SSc. Further research is warranted to determine the utility of measuring endothelin-1 in SSc subgroups with different extent of fibrosis and organ involvement.

Registration

PROSPERO registration number - CRD42024566461.

Spatial transcriptomics in autoimmune rheumatic disease: potential clinical applications and perspectives

Spatial transcriptomics is a cutting-edge technology that analyzes gene expression at the cellular level within tissues while integrating spatial location information. This concept, which combines high-plex RNA sequencing with spatial data, emerged in the early 2010s. Spatial transcriptomics has rapidly expanded with the development of technologies such as in situ hybridization, in situ sequencing, in situ spatial barcoding, and microdissection-based methods. Each technique offers advanced mapping resolution and precise spatial assessments at the single-cell level. Over the past decade, the use of spatial transcriptomics on clinical samples has enabled researchers to identify gene expressions in specific diseased foci, significantly enhancing our understanding of cellular interactions and disease processes. In the field of rheumatology, the complex and elusive pathophysiology of diseases such as rheumatoid arthritis, systemic lupus erythematosus, and Sjögren's syndrome remains a challenge for personalized treatment. Spatial transcriptomics provides insights into how different cell populations interact within disease foci, such as the synovial tissue, kidneys, and salivary glands. This review summarizes the development of spatial transcriptomics and current insights into the pathophysiology of autoimmune rheumatic diseases, focusing on immune cell distribution and cellular interactions within tissues. We also explore the potential of spatial transcriptomics from a clinical perspective and discuss the possibilities for translating this technology to the bedside.

Efficacy and safety of mesenchymal stromal cell transplantation in the treatment of autoimmune and rheumatic immune diseases: a systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

This study aims to assess the effectiveness and safety of mesenchymal stem cell (MSC) transplantation in the treatment of autoimmune and rheumatic immune diseases through randomized controlled trials (RCTs).

METHODS

Two researchers conducted a comprehensive search of Chinese and English databases from their inception until Dec. 2023. The literature screening and data extraction were then performed. Statistical analysis was carried out using RevMan 5.4 software.

RESULTS

A total of 42 relevant RCTs, involving 2,183 participants, were ultimately included in this study. These RCTs encompassed four types of rheumatic immune and bone diseases, namely rheumatoid arthritis (RA), osteoarthritis (OA), spondyloarthritis, systemic sclerosis arthritis, systemic lupus erythematosus (SLE), inflammatory bowel disease, multiple sclerosis, primary Sjögren's syndrome (PSS). The systematic review indicates that MSC transplantation may improve spondyloarthritis, RA, PSS. The meta-analysis reveals that MSC transplantation significantly improved symptoms in patients with OA [VAS (visual analogue scale): bone marrow: SMD = - 0.95, 95% CI - 1.55 to - 0.36, P = 0.002; umbilical cord: SMD = - 1.25, 95% CI - 2.04 to - 0.46, P = 0.002; adipose tissue: SMD = -1.26, 95% CI -1.99 to - 0.52, P = 0.0009)], SLE [Systemic lupus erythematosus disease activity index (SLEDAI): SMD = - 2.32, 95% CI - 3.59 to - 1.06, P = 0.0003], inflammatory bowel disease [clinical efficacy: RR = 2.02, 95% CI 1.53 to 2.67, P < 0.00001]. However, MSC transplantation may not improve the symptoms of multiple sclerosis and systemic sclerosis (Ssc). Importantly, MSC transplantation did not increase the incidence of adverse events (OA: RR = 1.23, 95% CI 0.93 to 1.65, P = 0.15; SLE: RR = 0.83, 95% CI 0.28 to 2.51, P = 0.76; Inflammatory bowel disease: RR = 0.99, 95% CI 0.81 to 1.22, P = 0.96; Multiple sclerosis: RR = 1.12, 95% CI 0.81 to 1.53, P = 0.50), supporting its safety profile across the included studies. These findings suggest that MSC transplantation holds promise for several rheumatic and autoimmune diseases while highlighting areas where further research is warranted.

CONCLUSION

MSC transplantation may have the potential to treat autoimmune and rheumatic immune diseases. Moreover. MSC transplantation appears to be relatively safe and could be considered as a viable alternative treatment option for autoimmune and rheumatic immune diseases.

Extracellular Matrix-Inspired Dendrimer Nanogels Encapsulating Cyclophosphamide for Systemic Sclerosis Treatment

Cyclophosphamide has a certain therapeutic effect on treating systemic sclerosis (SSc), while difficulties exist in controlling severe systematic side effects and enhancing targeting capacity. Here, inspired from the natural extracellular matrix composition, we propose a cyclophosphamide-encapsulated nanogel based on dendritic polymers polyamidoamine (PAMAM) for SSc treatment. We combine bovine serum albumin and generation 5 (G5) PAMAM dendrimers with polyphenol modification to obtain nanogels featured with antioxidant and anti-inflammatory effects. The nanogels can possess excellent biocompatibility and prevent fibroblasts from oxidative stress damage and TGF-β-mediated activation. Furthermore, in the bleomycin-induced SSc mouse model, dendrimer nanogels encapsulating cyclophosphamide also exhibit the ability to attenuate fibrosis by modulating immunity, suppressing inflammation, and reducing collagen synthesis. These findings underscore the value of this dendritic polymer nanogel in the treatment of chronic SSc, indicating its broader potential for clinical applications.

Post hoc comparison of the effectiveness of tocilizumab, rituximab, mycophenolate mofetil, and cyclophosphamide in patients with SSc-ILD from the EUSTAR database

OBJECTIVES

Tocilizumab (TCZ), rituximab (RTX), mycophenolate mofetil (MMF), and cyclophosphamide (CYC) are the immunosuppressants (IS) most frequently used for systemic sclerosis-associated interstitial lung disease (SSc-ILD). This post hoc study aimed to compare their effectiveness in patients with SSc-ILD from the European Scleroderma Trials and Research (EUSTAR) database.

METHODS

We included radiologically confirmed SSc-ILD patients with treatment records for TCZ, RTX, MMF, or CYC. The primary endpoint was the change in forced vital capacity (FVC) percent predicted from baseline to follow-up. Analyses were adjusted for clinical and demographic characteristics, cotreatments, and follow-up duration using propensity score-based inverse probability of treatment weighting (IPTW).

RESULTS

Nine hundred fifty-five patients with 997 treatment observations were included in the study. The median follow-up time was 11 months (IQR, 8-14 months). After IPTW, the changes in FVC percent predicted were not significantly different in the multigroup comparison (P = .101). Paired comparisons showed no significant difference. CYC was associated with stable FVC in logistic regression. For subgroup analysis, the treatment differences in change of FVC percent predicted among the 4 groups were not significant in patients with combination IS or previous exposure to TCZ, RTX, or conventional IS, as well as in current smokers or nonsmokers, and regardless of whether observations started either at the initiating or noninitiating stage of the treatment.

CONCLUSIONS

In this first large real-world study, the effectiveness of TCZ, RTX, MMF, and CYC on FVC change in SSc-ILD patients was not statistically different.

CD19-targeting CAR T-cell therapy in patients with diffuse systemic sclerosis: a case series

BACKGROUND

CD19-targeting chimeric antigen receptor (CAR) T-cell therapy has shown remarkable outcomes in patients with systemic lupus erythematosus. The effects of CD19-targeting CAR T cells on organ manifestations in patients with systemic sclerosis have yet to be characterised. B cells have a central role in the pathogenesis of systemic sclerosis. We present a detailed analysis of the effects of CD19-targeting CAR T-cell therapy in patients with systemic sclerosis.

METHODS

Six patients with severe diffuse systemic sclerosis with an insufficient response to at least two treatments were consecutively recruited at the Department of Internal Medicine 3, University Hospital Erlangen (Erlangen, Germany) to receive CD19-targeting CAR T-cell treatment (1 × 106 CAR T cells per kg bodyweight). Events were predefined by progression of interstitial lung disease, onset of congestive heart failure, onset of renal failure, onset of arterial hypertension, or initiation of new immunosuppressive or antifibrotic therapy. Event-free time or treatment intensification after study entry was the primary outcome. Key secondary outcomes included changes in the modified Rodnan Skin Score (mRSS), imaging (a component of the assessment of lung fibrosis), laboratory assessments, patient-reported outcomes, and a modified version of the American College of Rheumatology Composite Response Index in Systemic Sclerosis (ACR-CRISS), assessed at baseline, 3 months, 6 months, 9 months, and 12 months.

FINDINGS

Between April 20, 2022, and Nov 8, 2023, six patients with severe diffuse systemic sclerosis (median age 42 years [IQR 36-53]; four men and two women; all White European) were recruited and received CD19-targeted CAR T-cell therapy. The median follow-up time was 487 days (IQR 342-585). No events occurred within the observational period. Probability of improvement in the ACR-CRISS score increased to a median of 100% (IQR 100-100) at 6 months. Median mRSS decreased by 31% (IQR 29-38), corresponding to a median of 8 points (IQR 7-13) within 100 days. The extent of disease on CT scan decreased by a median of 4% (IQR 3-4) due to reduction of ground-glass opacities while the reticular pattern remained stable. Forced vital capacity improved by a median of 195 mL (IQR 18-275) at the latest observational timepoint.

INTERPRETATION

We provide the first evidence that CD19-targeting CAR T-cell therapy might intercept with the progression of fibrotic organ manifestations in patients with systemic sclerosis.

FUNDING

Deutsche Forschungsgemeinschaft, Deutsche Krebshilfe, ELAN-Foundation Erlangen, IZKF Erlangen, and Bundesministerium für Bildung und Forschung.

Common biomarkers of idiopathic pulmonary fibrosis and systemic sclerosis based on WGCNA and machine learning

Interstitial lung disease (ILD) is known to be a major complication of systemic sclerosis (SSc) and a leading cause of death in SSc patients. As the most common type of ILD, the pathogenesis of idiopathic pulmonary fibrosis (IPF) has not been fully elucidated. In this study, weighted correlation network analysis (WGCNA), protein‒protein interaction, Kaplan-Meier curve, univariate Cox analysis and machine learning methods were used on datasets from the Gene Expression Omnibus database. CCL2 was identified as a common characteristic gene of IPF and SSc. The genes associated with CCL2 expression in both diseases were enriched mainly in chemokine-related pathways and lipid metabolism-related pathways according to Gene Set Enrichment Analysis. Single-cell RNA sequencing (sc-RNAseq) revealed a significant difference in CCL2 expression in alveolar epithelial type 1/2 cells, mast cells, ciliated cells, club cells, fibroblasts, M1/M2 macrophages, monocytes and plasma cells between IPF patients and healthy donors. Statistical analyses revealed that CCL2 was negatively correlated with lung function in IPF patients and decreased after mycophenolate mofetil (MMF) treatment in SSc patients. Finally, we identified CCL2 as a common biomarker from IPF and SSc, revealing the common mechanism of these two diseases and providing clues for the study of the treatment and mechanism of these two diseases.

Physiology-based pharmacokinetic model with relative transcriptomics to evaluate tissue distribution and receptor occupancy of anifrolumab

Type I interferons contribute to the pathogenesis of several autoimmune disorders, including systemic lupus erythematosus (SLE), systemic sclerosis, cutaneous lupus erythematosus, and myositis. Anifrolumab is a monoclonal antibody that binds to subunit 1 of the type I interferon receptor (IFNAR1). Results of phase IIb and phase III trials led to the approval of intravenous anifrolumab 300 mg every 4 weeks (Q4W) alongside standard therapy in patients with moderate-to-severe SLE. Here, we built a population physiology-based pharmacokinetic (PBPK) model of anifrolumab by utilizing the physiochemical properties of anifrolumab, binding kinetics to the Fc gamma neonatal receptor, and target-mediated drug disposition properties. A novel relative transcriptomics approach was employed to determine IFNAR1 expression in tissues (blood, skin, gastrointestinal tract, lungs, and muscle) using mRNA abundances from bioinformatic databases. The IFNAR1 expression and PBPK model were validated by testing their ability to predict clinical pharmacokinetics over a large dose range from different clinical scenarios after subcutaneous and intravenous anifrolumab dosing. The validated PBPK model predicted high unbound local concentrations of anifrolumab in blood, skin, gastrointestinal tract, lungs, and muscle, which exceeded its IFNAR1 dissociation equilibrium constant values. The model also predicted high IFNAR1 occupancy with subcutaneous and intravenous anifrolumab dosing. The model predicted more sustained IFNAR1 occupancy ≥90% with subcutaneous anifrolumab 120 mg once-weekly dosing vs. intravenous 300 mg Q4W dosing. The results informed the dosing of phase III studies of anifrolumab in new indications and present a novel approach to PBPK modeling coupled with relative transcriptomics in simulating pharmacokinetics of therapeutic monoclonal antibodies.

Neurovascular dysregulation in systemic sclerosis: novel insights into pathophysiology, diagnosis, and treatment utilizing invasive cardiopulmonary exercise testing

PURPOSE OF REVIEW

Pathologic abnormalities in skeletal muscle and the systemic vasculature are common in patients with systemic sclerosis (SSc). These abnormalities may lead to impaired systemic peripheral oxygen extraction (EO 2 ), known as neurovascular dysregulation, which may be because of abnormal blood flow distribution in the vasculature, microvascular shunting, and/or skeletal muscle mitochondrial dysfunction. Findings from invasive cardiopulmonary exercising testing (iCPET) provide important insights and enable diagnosis and treatment of this SSc disease manifestation.

RECENT FINDINGS

Recent findings from noninvasive cardiopulmonary exercise testing (niCPET) support the existence of neurovascular dysregulation in patients with SSc. Invasive cardiopulmonary exercise testing (iCPET) has pointed to reduced systemic vascular distensibility as a possible mechanism for neurovascular dysregulation in patients with connective tissue diseases, including SSc.

SUMMARY

Neurovascular dysregulation is likely an underappreciated cause of exercise impairment and dyspnea in patients with SSc in the presence or absence of underlying cardiopulmonary disease. It is posited to be related to microcirculatory and muscle dysfunction. Further studies are needed to clarify the pathophysiology of neurovascular dysregulation in SSc and to identify novel treatment targets and additional therapies.

Single-cell transcriptomic profiling of lung fibroblasts in a bleomycin-induced systemic sclerosis mouse model

Systemic sclerosis (SSc) is a complex autoimmune disease characterized by fibrosis, vascular abnormalities, and immune dysfunction, with no definitive cure. Patients with progressive pulmonary fibrosis face a high mortality risk, underscoring the urgent need for effective treatments. Although fibroblasts are recognized as key drivers of fibrosis, the precise molecular mechanisms remain poorly understood. In this study, we employ single-cell RNA sequencing to explore the role of fibroblasts in pulmonary fibrosis. Using a mouse model induced by subcutaneous bleomycin administration, we identify two distinct fibroblast subpopulations: nephronectin-positive (NPNT) and peptidase inhibitor 16-positive cells(PI16). NPNT-positive fibroblasts, located around the alveoli, exhibit increased extracellular matrix expression following bleomycin treatment. To further understand pulmonary fibrosis, subcutaneous and intratracheal bleomycin-induced mouse models are compared. A comparative gene expression analysis reveals shared and unique features between the models, highlighting the complexity of the fibrotic process. These findings offer valuable insights into the molecular mechanisms of SSc-associated pulmonary fibrosis and may inform the development of therapies targeting specific fibroblast subpopulations or pathways.

CD19 CAR-T cell therapy: a new dawn for autoimmune rheumatic diseases?

Autoimmune rheumatic diseases (ARDs), such as rheumatoid arthritis, systemic lupus erythematosus, and systemic sclerosis, involve dysregulated immune responses causing chronic inflammation and tissue damage. Despite advancements in clinical management, many patients do not respond to current treatments, which often show limited efficacy due to the persistence of autoreactive B cells. Chimeric antigen receptor (CAR)-T cell therapy, which has shown success in oncology for B cell malignancies, targets specific antigens and involves the adoptive transfer of genetically engineered T cells. CD19 CAR-T cells, in particular, have shown promise in depleting circulating B cells and achieving clinical remission. This review discusses the potential of CD19 CAR-T cells in ARDs, highlighting clinical achievements and addressing key considerations such as optimal target cell populations, CAR construct design, acceptable toxicities, and the potential for lasting immune reset, crucial for the safe and effective adoption of CAR-T cell therapy in autoimmune treatments.

Inhibiting triggering receptor expressed on myeloid cells 1 signaling to ameliorate skin fibrosis

Systemic sclerosis (SSc) is characterized by immune system failure, vascular insult, autoimmunity, and tissue fibrosis. TGF-β is a crucial mediator of persistent myofibroblast activation and aberrant extracellular matrix production in SSc. The factors responsible for this are unknown. By amplifying pattern recognition receptor signaling, triggering receptor expressed on myeloid cells 1 (TREM-1) is implicated in multiple inflammatory conditions. In this study, we used potentially novel ligand-independent TREM-1 inhibitors in preclinical models of fibrosis and explanted SSc skin fibroblasts in order to investigate the pathogenic role of TREM-1 in SSc. Selective pharmacological TREM-1 blockade prevented and reversed skin fibrosis induced by bleomycin in mice and mitigated constitutive collagen synthesis and myofibroblast features in SSc fibroblasts in vitro. Our results implicate aberrantly activated TREM-1 signaling in SSc pathogenesis, identify a unique approach to TREM-1 blockade, and suggest a potential therapeutic benefit for TREM-1 inhibition.

Fibrosis mechanisms in systemic sclerosis and new potential therapies

Systemic sclerosis is a rare rheumatic disease characterized by immune cell activation, tissue fibrosis, and endothelial dysfunction. Extracellular matrix synthesis disorder causes widespread fibrosis, primarily in skin and internal organs. Various factors such as TGFβ, VEGF, Galectin-3, and signaling pathways like Wnt/β-catenin are involved in pathophysiological processes. Treatment lacks a unified approach but combines diverse modalities tailored to disease subtype and progression. Current therapeutic strategies include biologics, JAK inhibitors, and IL-6 pathway modulators. Monoclonal antibodies and hypomethylating agents demonstrate potential in fibrosis inhibition. This review focuses on emerging therapeutic evidence regarding drugs targeting collagen, cytokines, and cell surface molecules in systemic sclerosis, aiming to provide insight into potential innovative treatment strategies.

Critical Analysis of Cytoplasmic Progression of Inflammatory Signaling Suggests Potential Pharmacologic Targets for Wound Healing and Fibrotic Disorders

Successful skin wound healing is dependent on an interplay between epidermal keratinocytes and dermal fibroblasts as they react to local extracellular factors (DAMPs, PAMPs, cytokines, etc.) surveyed from that environment by numerous membrane receptors (e.g., TLRs, cytokine receptors, etc.). In turn, those receptors are the start of a cytoplasmic signaling pathway where balance is key to effective healing and, as needed, cell and matrix regeneration. When directed through NF-κB, these signaling routes lead to transient responses to the benefit of initiating immune cell recruitment, cell replication, local chemokine and cytokine production, and matrix protein synthesis. The converse can also occur, where ongoing canonical NF-κB activation leads to chronic, hyper-responsive states. Here, we assess three key players, TAK1, TNFAIP3, and TNIP1, in cytoplasmic regulation of NF-κB activation, which, because of their distinctive and yet inter-related functions, either promote or limit that activation. Their balanced function is integral to successful wound healing, given their significant control over the expression of inflammation-, fibrosis-, and matrix remodeling-associated genes. Intriguingly, these three proteins have also been emphasized in dysregulated NF-κB signaling central to systemic sclerosis (SSc). Notably, diffuse SSc shares some tissue features similar to an excessive inflammatory/fibrotic wound response without eventual resolution. Taking a cue from certain instances of aberrant wound healing and SSc having some shared aspects, e.g., chronic inflammation and fibrosis, this review looks for the first time, to our knowledge, at what those pathologies might have in common regarding the cytoplasmic progression of NF-κB-mediated signaling. Additionally, while TAK1, TNFAIP3, and TNIP1 are often investigated and reported on individually, we propose them here as three proteins whose consequences of function are very highly interconnected at the signaling focus of NF-κB. We thus highlight the emerging promise for the eventual clinical benefit derived from an improved understanding of these integral signal progression modulators. Depending on the protein, its indirect or direct pharmacological regulation has been reported. Current findings support further intensive studies of these points in NF-κB regulation both for their basic function in healthy cells as well as with the goal of targeting them for translational benefit in multiple cutaneous wound healing situations, whether stemming from acute injury or a dysregulated inflammatory/fibrotic response.

Vascular endothelial growth factor as a potential biomarker in systemic sclerosis: a systematic review and meta-analysis

Introduction

Systemic sclerosis (SSc), a chronic autoimmune condition, is characterized by microvascular dysfunction, ineffective angiogenesis, and fibrosis. The identification of robust biomarkers reflecting these processes may assist in clinical management and lead to the discovery of new therapies. We sought to address this issue by conducting a systematic review and meta-analysis of studies investigating one such biomarker, vascular endothelial growth factor (VEGF), in SSc patients and healthy controls and in SSc patients with localized or diffuse disease, different video capillaroscopy patterns (early, active, or late), and presence or absence of complications.

Methods

We searched PubMed, Scopus, and Web of Science from inception to 15 May 2024. We assessed the risk of bias and the certainty of evidence using the JBI checklist for analytical studies and GRADE, respectively.

Results

In 42 eligible studies, compared to controls, patients with SSc had significantly higher plasma or serum VEGF concentrations (standard mean difference, SMD=0.93, 95% CI 0.71 to 1.15, p<0.001; moderate certainty). In further analyses, VEGF concentrations were significantly higher in SSc patients with diffused disease than those with localized disease (SMD=0.30, 95% CI 0.01 to 0.59, p=0.046; very low certainty), in patients with late vs. active video capillaroscopy pattern (SMD=0.35, 95% CI 0.09 to 0.61, p=0.008; very low certainty), and in patients with pulmonary hypertension than those without (SMD=0.93, 95% CI 0.34 to 1.53, p=0.002; very low certainty). By contrast, no significant differences were observed between SSc patients with and without digital ulcers, interstitial lung disease, and telangiectasias, whereas limited evidence was available for alveolitis. Meta-regression and subgroup analysis of studies investigating VEGF in SSc patients and controls showed no significant associations between the effects size and various patient and study characteristics, including SSc duration and use of corticosteroids, immunosuppressors and vasodilators. By contrast, significant associations were observed with the geographical location where the study was conducted.

Discussion

The results of this systematic review and meta-analysis suggest that VEGF can be useful in the assessment and management of SSc and in the identification of novel therapeutic strategies in this patient group.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero, identifier CRD42024552925.

Impact of autoantibody status on stratifying the risk of organ involvement and mortality in SSc: experience from a multicentre French cohort of 1605 patients

INTRODUCTION

Systemic sclerosis (SSc) is a rare autoimmune disease currently classified into two subgroups based on skin extension. The aim of this study was to determine in a large cohort whether the determination of autoantibody (AAb) profile among a full antinuclear AAbs panel including nine specificities had a higher impact than skin phenotype on stratifying the risk of organ involvement and mortality in SSc.

METHODS

Data for patients with SSc followed in seven French university hospitals were retrospectively analysed in terms of skin phenotype, AAbs (anti-topoisomerase I (ATA), anticentromere (ACA), anti-RNA polymerase III (anti-RNAPIII), anti-U1RNP, anti-U3RNP, anti-Pm/Scl, anti-Ku, anti-Th/To, anti-NOR90), organ involvement and mortality. Multivariate analyses were performed to identify independent factors associated with organ involvement and mortality.

RESULTS

We included 1605 patients with SSc (367 with diffuse cutaneous SSc). On multivariate analysis, ATAs were associated with interstitial lung disease and mortality (OR=3.27 (95% CI 2.42 to 4.42); HR=1.9 (95% CI 1.01 to 3.58)), anti-RNAPIII with scleroderma renal crisis and mortality (OR=7.05 (95% CI 2.98 to 16.72); HR=2.35 (95% CI 1.12 to 4.93)), anti-U1RNP with arthritis (OR=3.79 (95% CI 2.16 to 6.67)), anti-Pm/Scl and anti-Ku with myositis (OR=7.09 (95% CI 3.87 to 12.98) and 7.99 (95% CI 2.41 to 26.46)). The skin phenotype was not associated with survival or organ involvement on multivariate analysis without stepwise selection.

CONCLUSION

This study unravels, by contrast with skin phenotype, a strong association between AAbs specificities, organ involvement and outcome in SSc and suggests that patients' classification based on only skin extension is not sufficient for defining prognosis and phenotype.

Single-cell analysis in rheumatic and allergic diseases: insights for clinical practice

Since the advent of single-cell RNA sequencing (scRNA-seq) methodology, single-cell analysis has become a powerful tool for exploration of cellular networks and dysregulated immune responses in disease pathogenesis. Advanced bioinformatics tools have enabled the combined analysis of scRNA-seq data and information on various cell properties, such as cell surface molecular profiles, chromatin accessibility and spatial information, leading to a deeper understanding of pathology. This Review provides an overview of the achievements in single-cell analysis applied to clinical samples of rheumatic and allergic diseases, including rheumatoid arthritis, systemic lupus erythematosus, systemic sclerosis, allergic airway diseases and atopic dermatitis, with an expanded scope beyond peripheral blood cells to include local diseased tissues. Despite the valuable insights that single-cell analysis has provided into disease pathogenesis, challenges remain in translating single-cell findings into clinical practice and developing personalized treatment strategies. Beyond understanding the atlas of cellular diversity, we discuss the application of data obtained in each study to clinical practice, with a focus on identifying biomarkers and therapeutic targets.

Digital ulcers associated with scleroderma: A major unmet medical need

Scleroderma or systemic sclerosis (SSc)-associated digital ischaemic complications, such as digital ulcers (SSc-DUs), appear relatively early during the disease course and are a major burden with substantial deterioration of quality of life. Expert rheumatologist and wound specialists have defined a DU; however, international application of the definition is still disorganised. Appearance of SSc-DUs is secondary to the onset of Raynaud's phenomenon and as a consequence, recommended first-line of treatment mainly includes vasodilators; however, many DUs are refractory to this treatment. Despite important practical issues, such as a lack of well-characterised SSc-wound healing animal model, significant efforts are needed to mechanistically understand the pathogenesis of SSc-DUs for developing clinically targetable disease modifying therapies.

EDNRA affects susceptibility to large artery atherosclerosis stroke through potential inflammatory pathway

This study aimed to explore the potential association between Endothelin type A receptor (EDNRA) genetic polymorphisms and susceptibility to large artery atherosclerotic stroke (LAA), as well as the involvement of inflammation mechanisms. We recruited Han Chinese patients with LAA and age- and sex-matched controls. The distribution of alleles and genotypes for 16 single nucleotide polymorphisms (SNPs) in EDNRA was analyzed using dominant, recessive, and co-dominant genetic models between cases and controls. We quantified the mRNA and protein levels of EDNRA and NLRP3 genes, and concentrations of inflammatory factors (TNFα, IL-1β, IL-6, IL-8, IL-10, IL-18, and CCL18) in peripheral blood samples randomly selected from cases and controls. We also investigated the relationship between these SNPs, gene expression patterns and inflammatory factor levels. A total of 428 LAA cases and 434 controls were enrolled in this study. The results showed that rs5343 TT genotype of EDNRA was significantly associated with an increased risk of LAA (OR = 3.243, 95%CI = 1.608-6.542, P = 0.001). It also demonstrated a significant upregulation level of NLRP3 as well as higher concentrations of IL-10, IL-18, and CCL-18 in cases compared to controls. Besides, we discovered that the EDNRA polymorphisms were linked to NLRP3, IL-6, IL-10, and IL-18 levels in cases. There existed a positive correlation between EDNRA transcription levels and both NLRP3 transcript levels (r = 0.437, p < 0.001) and IL-18 concentrations (r = 0.212, p < 0.001). EDNRA is linked to susceptibility of LAA. This association may be attributed to the NLRP3-mediated inflammatory pathway.

Long-term outcome of autologous haematopoietic stem cell transplantation in patients with systemic sclerosis: a comparison with patients treated with rituximab and with traditional immunosuppressive agents

BACKGROUND

Autologous haematopoietic stem cell transplantation (AHSCT) is more effective than conventional immunosuppressive therapies (CIT) in improving the outcome of patients with rapidly progressive diffuse cutaneous systemic sclerosis (dcSSc). So far, there is still a paucity of data comparing AHSCT with rituximab (RTX). Aim of the study is to retrospectively compare, in patients with dcSSc, the effectiveness of AHSCT with that of RTX and CIT.

METHODS

Thirty-five dcSSc AHSCT-treated patients were compared with 29 and 36 matched cases treated with RTX and CIT, respectively. The patients were followed up for 5 years by assessing selected outcome measures every year. Overall survival, modified Rodnan skin score (mRSS), lung function tests (FVC and DLCO), and the revised EUSTAR Activity Index (REAI) were the outcome measures chosen to evaluate the therapy efficacy.

RESULTS

AHSCT was significantly more effective than RTX and CIT in prolonging survival, inducing a rapid reduction of the mRSS and REAI and maintaining the baseline level of lung function tests for a longer time. RTX therapy was also superior to CIT in reducing REAI, mRSS and in saving lung function.

CONCLUSION

AHSCT is more effective than both RTX and CIT in prolonging survival and inducing prolonged remission in patients with rapidly progressive dcSSc.

Nur77 ameliorates cyclophosphamide-induced ovarian insufficiency in mice by inhibiting oxidative damage and cell senescence

Premature ovarian failure (POF) is among the primary causes of ovarian dysfunction that severely affects women's physical and mental health. The main purpose of this study was to explore the expression level of Nerve growth factor-induced protein B (Nur77/NR4A1) in cyclophosphamide (CTX)-induced POF. We then tested whether Nur77 can exert a protective effect after CTX treatment and investigated the mechanism of Nur77's role during ovarian injury. CTX promotes follicular atresia by inducing redox imbalance, apoptosis, and senescence, thereby causing direct toxicity to gonads. Additionally, CTX decreases ovarian reserve consumption by stimulating the excessive activation of primordial follicles. Nur77 can be stimulated by oxidative stress, DNA damage, metabolism, inflammation, etc. However, its relationship with POF remains unelucidated. We here found that Nur77 is expressed at low levels in POF ovaries. Therefore, Nur77 was identified as a regulator of ovarian injury and follicular development. According to the results, Nur77 overexpression alleviated redox imbalances, reduced cell senescence and apoptosis, and improved follicular reserve. Nur77 protects ovarian function by restoring disordered sex hormone levels and estrus cycles and promoting follicle growth and development at all levels. Moreover, the rapamycin protein kinase (AKT)/mammalian target of the rapamycin (mTOR) is a crucial regulator of the primordial follicle pool and follicular development. A relationship was observed between Nur77 and AKT through string and molecular docking. Experiments confirmed the involvement of the AKT/mTOR signaling pathway in the regulatory role of Nur77 in ovarian function. Thus, Nur77 is a critical target for POF prevention and treatment.

Tocilizumab plus Nintedanib for progressive interstitial lung disease in systemic sclerosis: a one-year observational study

Randomized controlled trials have recently shown that both the IL-6 inhibitor Tocilizumab and the antifibrotic Nintedanib are efficacious for Systemic Sclerosis (SSc)-associated progressive interstitial lung disease (ILD). Since real-world clinical data on Tocilizumab/Nintedanib combination are lacking, we report on their long-term safety and efficacy. Consecutive patients who received off-label Tocilizumab for SSc plus Nintedanib for progressive ILD were retrospectively studied. Adverse events, and changes in Forced Vital Capacity (FVC), Diffucing Capacity for Carbon Monoxide (DLCO) and high resolution chest tomography (HRCT) between baseline and 6 and 12 months were assessed. Tocilizumab/Nintedanib combination was well tolerated by all 20 patients [aged 52 ± 13 years (mean ± SD), 14 women, 15 diffuse SSc, disease duration of 5.7 ± 4.9 years]; 7 of 20 patients received concomitant mycophenolate mofetil safely. No serious adverse events or laboratory abnormalities were noted. Five patients developed persistent diarrhea and 2 of them reduced dosage of Nintedanib. Baseline FVC (74%±12%) and DLCO (45%±10%) remained overall stable both at 6 months (73.5%±13% and 46%±11%, respectively) and 12 months (73%±14% and 45%±11%, respectively), regardless of disease duration. The extent of fibrotic reticular pattern in available pairs of HRCTs (n = 12) remained also stable at 12 months, whereas proportion (%) of ground glass opacities decreased from 29%±16 to 21%±14% (p = 0.048); improvement in HRCTs by almost 75% was noted in 2 of these12 patients. Tocilizumab/Nintedanib combination for one year was safe and stabilized lung function in real-world SSc patients with progressive ILD. Additional studies of this combination treatment in SSc-ILD are warranted.

Stimuli-responsive drug delivery systems for inflammatory skin conditions

Inflammatory skin conditions highly influence the quality of life of the patients suffering from these disorders. Symptoms include red, itchy and painful skin lesions, which are visible to the rest of the world, causing stigmatization and a significantly lower mental health of the patients. Treatment options are often unsatisfactory, as they suffer from either low patient adherence or the risk of severe side effects. Considering this, there is a need for new treatments, and notably of new ways of delivering the drugs. Stimuli-responsive drug delivery systems are able to deliver their drug cargo in response to a given stimulus and are, thus, promising for the treatment of inflammatory skin conditions. For example, the use of external stimuli such as ultraviolet light, near infrared radiation, or alteration of magnetic field enables drug release to be precisely controlled in space and time. On the other hand, internal stimuli induced by the pathological condition, including pH alteration in the skin or upregulation of reactive oxygen species or enzymes, can be utilized to create drug delivery systems that specifically target the diseased skin to achieve a better efficacy and safety. In the latter context, however, it is of key importance to match the trigger mechanism of the drug delivery system to the actual pathological features of the specific skin condition. Hence, the focus of this article is placed not only on reviewing stimuli-responsive drug delivery systems developed to treat specific inflammatory skin conditions, but also on critically evaluating their efficacy in the context of specific skin diseases. STATEMENT OF SIGNIFICANCE: Skin diseases affect one-third of the world's population, significantly lowering the quality of life of the patients, who deal with symptoms such as painful and itchy skin lesions, as well as stigmatization due to the visibility of their symptoms. Current treatments for inflammatory skin conditions are often hampered by low patient adherence or serious drug side effects. Therefore, more emphasis should be placed on developing innovative formulations that provide better efficacy and safety for patients. Stimuli-responsive drug delivery systems hold considerable promise in this regard, as they can deliver their cargo precisely where and when it is needed, reducing adverse effects and potentially offering better treatment outcomes.

Emotional intelligence: a novel predictor of quality of life in patients with systemic sclerosis

Systemic sclerosis (SSc), a chronic systemic autoimmune disease, affects skin and internal organs compromising organ function and leading to significant morbidity and poor health-related quality of life (HrQoL). This cross-sectional study investigated whether HrQoL is influenced by trait emotional intelligence (TEI). Sixty patients with SSc (Female: 86.67%) completed the socio-demographic characteristics form, TEI Questionnaire Short-Form (TEIQue-SF), and Short-Form Health Survey (SF-36). Sixty healthy controls were also completed the TEIQue-SF. A series of multiple linear regression analyses with correlation matrix was used to analyze SF-36 domains as dependent variables with TEI domains (well-being, self-control, emotionality, sociability) as independent variables. The average age of participants was 57.3 ± 12.9 years with a mean disease duration of 7.7 ± 6.7 years. Patients differed from controls in the sociability domain of TEI. TEI global was found to affect the physical and mental component summaries (p < .001), and all 8 dimensions of the HrQoL (p < .001). Age, disease duration, and gastrointestinal manifestations were negatively associated with various components of SF-36. TEI was positively associated with all dimensions of HrQoL. Understanding the relationship between TEI and HrQoL dimensions is important for the support and empowerment of SSc patients, as well as the establishment and implementation of appropriate psychotherapeutic interventions.

Towards a Better Prognosis in Patients with Systemic Sclerosis-Related Pulmonary Arterial Hypertension: Recent Developments and Perspectives

Precapillary pulmonary hypertension (PH) is a significant complication of systemic sclerosis (SSc). It represents one of the leading causes of morbidity and mortality, correlating with a significantly dismal prognosis and quality of life. Despite advancements in the management of patients with pulmonary arterial hypertension associated with SSc (SSc-PAH), no significant improvement has been reported in survival of patients with precapillary SSc-PH associated with extensive lung parenchyma disease. International expert consensus and guidelines for the management of PH recommend annual screening of SSc patients for early detection of pre-capillary PH. The implementation of screening algorithms capable of identifying patients with a high likelihood of developing PH could help limit unnecessary right-heart catheterization procedures and prevent significant delay in diagnosis. Furthermore, early initiation of up-front combination targeted therapy in patients with PAH has shown increase in survival rates, indicating that timely and aggressive medical therapy is key for stabilizing and even improving functional class, hemodynamic parameters and 6 min walking distance (6MWD) in this population. Further research is warranted into the benefit of PAH-targeted therapies in patients with PH associated with lung disease. Lastly, we discuss the potential role of immunosuppression using biologic agents in the therapeutic management of precapillary PH in SSc patients.

Clinical, mechanistic, and therapeutic landscape of cutaneous fibrosis

When dysregulated, skin fibrosis can lead to a multitude of pathologies. We provide a framework for understanding the wide clinical spectrum, mechanisms, and management of cutaneous fibrosis encompassing a variety of matrix disorders, fibrohistiocytic neoplasms, injury-induced scarring, and autoimmune scleroses. Underlying such entities are common mechanistic pathways that leverage morphogenic signaling, immune activation, and mechanotransduction to modulate fibroblast function. In light of the limited array of available treatments for cutaneous fibrosis, scientific insights have opened new therapeutic and investigative avenues for conditions that still lack effective interventions.

Rethinking of phosphodiesterase 5 inhibition: the old, the new and the perspective in human health

The phosphodiesterases type 5 (PDE5) are catalytic enzymes converting the second messenger cyclic guanosine monophosphate (cGMP) to 5' GMP. While intracellular cGMP reduction is associated with several detrimental effects, cGMP stabilization associates with numerous benefits. The PDE5 specific inhibitors, PDE5i, found their explosive fortune as first-line treatment for erectile dysfunction (ED), due to their powerful vasoactive properties. The favorable effect for ED emerged as side-effect when PDE5i were originally proposed for coronary artery disease (CAD). From that point on, the use of PDE5i captured the attention of researchers, clinicians, and companies. Indeed, PDE5-induced intracellular cGMP stabilization offers a range of therapeutic opportunities associated not only with vasoactive effects, but also with immune regulatory/anti-inflammatory actions. Chronic inflammation is acknowledged as the common link underlying most non-communicable diseases, including metabolic and cardiac diseases, autoimmune and neurodegenerative disorders, cancer. In this scenario, the clinical exploitation of PDE5i is undeniably beyond ED, representing a potential therapeutic tool in several human diseases. This review aims to overview the biological actions exerted by PDE5i, focusing on their ability as modulators of inflammation-related human diseases, with particular attention to inflammatory-related disorders, like cardiac diseases and cancer.

Allogeneic CD19-targeted CAR-T therapy in patients with severe myositis and systemic sclerosis

Allogeneic chimeric antigen receptor (CAR)-T cells hold great promise for expanding the accessibility of CAR-T therapy, whereas the risks of allograft rejection have hampered its application. Here, we genetically engineered healthy-donor-derived, CD19-targeting CAR-T cells using CRISPR-Cas9 to address the issue of immune rejection and treated one patient with refractory immune-mediated necrotizing myopathy and two patients with diffuse cutaneous systemic sclerosis with these cells. This study was registered at ClinicalTrials.gov (NCT05859997). The infused cells persisted for over 3 months, achieving complete B cell depletion within 2 weeks of treatment. During the 6-month follow-up, we observed deep remission without cytokine release syndrome or other serious adverse events in all three patients, primarily shown by the significant improvement in the clinical response index scores for the two diseases, respectively, and supported by the observations of reversal of inflammation and fibrosis. Our results demonstrate the high safety and promising immune modulatory effect of the off-the-shelf CAR-T cells in treating severe refractory autoimmune diseases.

Systemic sclerosis-associated interstitial lung disease: How to manage in 2024?

Systemic sclerosis (SSc) or scleroderma is an autoimmune disease characterized by immune dysregulation which leads to progressive fibrosis of the skin and internal organs. Interstitial lung disease (ILD) is present in approximately 65% of patients with SSc and it accounts for approximately 40% of all SSc deaths. Risk factors associated with the development of systemic sclerosis related interstitial lung disease (SSc-ILD) include male sex, African heritage, high modified Rodnan skin score (mRSS), presence of anti-Scl-70/Topoisomerase I antibodies, and nucleolar pattern on antinuclear antibody (ANA). The primary tool to diagnose ILD in patients with SSc is high-resolution computed tomography (HRCT). Full pulmonary function tests (PFTs) with diffusing capacity of the lungs for carbon monoxide (DLco) and ambulatory desaturation testing should be obtained following the diagnosis of SSc-ILD for disease monitoring. The purpose of this review is to provide an updated guide for the management of SSc-ILD. Our proposed first line treatment for SSc-ILD is immunosuppressive therapy such as mycophenolate mofetil, tocilizumab, and rituximab which are discussed in depth, and we present the evidence-based data that has justified the use of these pharmacotherapies. Other immunosuppressive treatments are also reviewed, and we discuss the role of antifibrotic therapy. Finally, we dive into other avenues of treatments such as chimeric antigen receptor (CAR)-T cell therapy and hematopoietic stem cell transplant.

Unraveling the immunometabolism puzzle: Deciphering systemic sclerosis pathogenesis

The article delves into the pathogenesis of systemic sclerosis (SSc) with an emphasis on immunometabolism dysfunctions. SSc is a complex autoimmune connective tissue disorder with skin and organ fibrosis manifestation, vasculopathy, and immune dysregulation. A growing amount of research indicates that immunometabolism plays a significant role in the pathogenesis of autoimmune diseases, including SSc. The review explores the intricate interplay between immune dysfunction and metabolic alterations, focusing on the metabolism of glucose, lipids, amino acids, the TCA (tricarboxylic acid) cycle, and oxidative stress in SSc disease. According to recent research, there are changes in various metabolic pathways that could trigger or perpetuate the SSc disease. Glycolysis and TCA pathways play a pivotal role in SSc pathogenesis through inducing fibrosis. Dysregulated fatty acid β-oxidation (FAO) and consequent lipid metabolism result in dysregulated extracellular matrix (ECM) breakdown and fibrosis induction. The altered metabolism of amino acids can significantly be involved in SSc pathogenesis through various mechanisms. Reactive oxygen species (ROS) production has a crucial role in tissue damage in SSc patients. Indeed, immunometabolism involvement in SSc is highlighted, which offers potential therapeutic avenues. The article underscores the need for comprehensive studies to unravel the multifaceted mechanisms driving SSc pathogenesis and progression.

Polyneuropathy in systemic sclerosis: exploring the causes and biomarkers

Introduction

Systemic sclerosis (SSc) is a rare autoimmune disease with multiple organ involvement; however, the contribution of the nervous system (NS) remains relatively understudied. There are no specific data on the role of the autoimmune response and inflammation in the development of peripheral nerve system (PNS) damage in SSc and markers to assess this damage have yet to be identified.

Objectives

The primary objective of this study was to define the autoimmune mechanisms that lead to neuropathy by identifying antibodies (Abs) that target certain component of the NS or are associated with SSc. The secondary objective was to identify markers of NS damage that correlate with the detection and progression of polyneuropathy (PNP).

Methods

This study included patients diagnosed with SSc who met ACR/EULAR 2013 classification criteria at two leading Latvian hospitals between January 2016 and December 2021. Patients underwent a nerve conduction study (NCS). The SSc-associated Abs, Abs against myelin-associated glycoprotein (MAG) and anti-ganglioside Abs (GM1, GM2, GD1a, GD1b and GQ1b) were analysed. Potential serum PNS biomarkers-neurofilament light chain (NfL), glial fibrillary acidic protein (GFAP), fibroblast growth factor 21 (FGF21) and growth/differentiation factor 15 (GDF15)-were measured.

Results

We recruited 103 Caucasian patients diagnosed with SSc. SSc-associated Abs did not differ significantly between patients with and without PNP (p > 0.05). Anti-MAG and anti-ganglioside Abs in patients with PNP did not present a significant increase above the reference range. NfL, GFAP and GDF15 were significantly elevated in the presence of PNP (p < 0.05), with a moderate to high effect size (r = 0.36-0.65). Our regression analysis revealed a strong association between the HAQ-DI score, older age, male gender and the risk of developing PNP.

Conclusion

The development of PNP in patients with SSc is most likely due to ageing, natural progression and the sequelae of the disease. Several serum biomarkers-NfL, GFAP and GDF15-could be used as relevant diagnostic biomarkers for PNP in patients with SSc. Future studies are warranted to validate the diagnostic efficacy of these biomarkers and to unravel the complex interplay of factors leading to PNP in patients with SSc.

Managing Symptoms of Systemic Sclerosis for the Allergist-Immunologist

PURPOSE OF REVIEW

Systemic sclerosis (SSc) is a chronic, multisystem, autoimmune disease characterized by fibrosis, vasculopathy and immune system dysregulation. We provide a comprehensive review of features of systemic sclerosis that can potentially present to the allergist.

RECENT FINDINGS

A thorough understanding of the management options is crucial for clinicians involved in the care of patients with SSc to optimize clinical outcomes. Management of systemic sclerosis has drastically changed in the last decade and continues to evolve. This review provides an overview of management strategies for the various symptoms including skin, upper and lower airway, gastrointestinal and vascular manifestations. Institution of treatment early in the disease, including referral to rheumatology or specialized scleroderma centers, can help to both prevent and manage disease complications, and improve patient quality-of-life. While the landscape of systemic sclerosis management has evolved, we continue to recognize that there is still a need for better biomarkers and targeted therapies.

Could Gas6/TAM Axis Provide Valuable Insights into the Pathogenesis of Systemic Sclerosis?

Systemic sclerosis (SSc) is a connective tissue disorder characterized by microvascular injury, extracellular matrix deposition, autoimmunity, inflammation, and fibrosis. The clinical complexity and high heterogeneity of the disease make the discovery of potential therapeutic targets difficult. However, the recent progress in the comprehension of its pathogenesis is encouraging. Growth Arrest-Specific 6 (Gas6) and Tyro3, Axl, and MerTK (TAM) receptors are involved in multiple biological processes, including modulation of the immune response, phagocytosis, apoptosis, fibrosis, inflammation, cancer development, and autoimmune disorders. In the present manuscript, we review the current evidence regarding SSc pathogenesis and the role of the Gas6/TAM system in several human diseases, suggesting its likely contribution in SSc and highlighting areas where further research is necessary to fully comprehend the role of TAM receptors in this condition. Indeed, understanding the involvement of TAM receptors in SSc, which is currently unknown, could provide valuable insights for novel potential therapeutic targets.

2023 Brazilian Society of Rheumatology guidelines for the treatment of systemic sclerosis

BACKGROUND

Systemic sclerosis (SSc) is a rare chronic autoimmune disease with heterogeneous manifestations. In the last decade, several clinical trials have been conducted to evaluate new treatment options for SSc. The purpose of this work is to update the recommendations of the Brazilian Society of Rheumatology in light of the new evidence available for the pharmacological management of SSc.

METHODS

A systematic review including randomized clinical trials (RCTs) for predefined questions that were elaborated according to the Patient/Population, Intervention, Comparison, and Outcomes (PICO) strategy was conducted. The rating of the available evidence was performed according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology. To become a recommendation, at least 75% agreement of the voting panel was needed.

RESULTS

Six recommendations were elaborated regarding the pharmacological treatment of Raynaud's phenomenon, the treatment (healing) and prevention of digital ulcers, skin involvement, interstitial lung disease (ILD) and gastrointestinal involvement in SSc patients based on results available from RCTs. New drugs, such as rituximab, were included as therapeutic options for skin involvement, and rituximab, tocilizumab and nintedanib were included as therapeutic options for ILD. Recommendations for the pharmacological treatment of scleroderma renal crisis and musculoskeletal involvement were elaborated based on the expert opinion of the voting panel, as no placebo-controlled RCTs were found.

CONCLUSION

These guidelines updated and incorporated new treatment options for the management of SSc based on evidence from the literature and expert opinion regarding SSc, providing support for decision-making in clinical practice.

Skin Ultrasound Assessment of Patients with Systemic Scleroderma-An Observational Study

This study aims to analyze the changes in dermal thickness in patients with systemic scleroderma (SSc) in comparison with normal skin and also compare clinical forms with diffuse and limited cutaneous involvement. The study group consisted of female patients diagnosed with SSc with a disease history not exceeding 5 years. The areas of interest for ultrasound examination included the proximal phalanx of the third finger, the second intermetacarpal space, and the extension surface of the lower third of the forearm. The study included 20 patients diagnosed with SSc and 14 controls. SSc patients were subdivided into two subgroups based on the clinical form. Compared to the control group, patients with SSc had higher mean measurements in all three skin areas, with statistically significant differences in the hand and forearm areas. Patients with diffuse SSc displayed, on average, higher skin thickness compared to limited SSc in all skin areas examined, with a statistically significant difference only in the forearm area. Based on disease manifestations, significant differences were observed only with regard to the presence of pulmonary hypertension in the diffuse SSc group. In conclusion, skin ultrasound is a useful and accessible imaging method for diagnosing and quantifying dermal fibrosis in systemic scleroderma.

Approach to the Atypical Wound

The heterogeneity of atypical wounds can present diagnostic and therapeutic challenges; however, as the prevalence of atypical wounds grows worldwide, prompt and accurate management is increasingly an essential skill for dermatologists. Addressing the underlying cause of an atypical wound is critical for successful outcomes. An integrated approach with a focus on pain management and patient engagement is recommended to facilitate enduring wound closure. Advances in treatment, in addition to further research and clinical training, are necessary to address the expanding burden of atypical wounds.

Trace Element Deficiency in Systemic Sclerosis-Too Much Effort for Some Traces?

Trace elements are essential for several physiological processes. To date, various data have suggested that inadequate levels of trace elements may be involved in the pathogenesis of different chronic diseases, including immune-mediated ones, or may develop during their course. Systemic sclerosis (SSc) is a complex autoimmune multisystemic disease, primarily characterized by microvascular dysregulation, the widespread activation of the immune system and tissue fibrosis. According to the latest reports regarding the pathogenesis of SSc, the main pathophysiological processes-inflammation, vasculopathy and fibrosis-may include various trace element derangements. The present literature review aims to update the available data regarding iron, zinc, copper and selenium status in SSc as well as to underline the possible implications of these trace elements in the complexity of the pathogenic process of the disease. We observe that the status of trace elements in SSc plays a crucial role in numerous pathogenic processes, emphasizing the necessity for proper monitoring and supplementation. The reported data are heterogenous and scarce, and future studies are needed in order to draw clearer conclusions about their complete spectrum.

Crucial Roles of RSAD2/viperin in Immunomodulation, Mitochondrial Metabolism and Autoimmune Diseases

Autoimmune diseases are typically characterized by aberrant activation of immune system that leads to excessive inflammatory reactions and tissue damage. Nevertheless, precise targeted and efficient therapies are limited. Thus, studies into novel therapeutic targets for the management of autoimmune diseases are urgently needed. Radical S-adenosyl methionine domain-containing 2 (RSAD2) is an interferon-stimulated gene (ISG) renowned for the antiviral properties of the protein it encodes, named viperin. An increasing number of studies have underscored the new roles of RSAD2/viperin in immunomodulation and mitochondrial metabolism. Previous studies have shown that there is a complex interplay between RSAD2/vipeirn and mitochondria and that binding of the iron-sulfur (Fe-S) cluster is necessary for the involvement of viperin in mitochondrial metabolism. Viperin influences the proliferation and development of immune cells as well as inflammation via different signaling pathways. However, the function of RSAD2/viperin varies in different studies and a comprehensive overview of this emerging theme is lacking. This review will describe the characteristics of RSAD2/viperin, decipher its function in immunometabolic processes, and clarify the crosstalk between RSAD2/viperin and mitochondria. Furthermore, we emphasize the crucial roles of RSAD2 in autoimmune diseases and its potential application value.

An Overview of Methotrexate Indications in Skin Diseases

Methotrexate is an immunosuppressive drug with remarkable therapeutic results in the treatment of autoimmune and proliferative skin diseases. Although it has been more than half a century since it was first introduced into the therapeutic arsenal of dermatologists, there are currently no standardized therapeutic protocols regarding the prescription of methotrexate in dermatology, with the exception of psoriasis treatment. This review aims to highlight the indications and benefits of methotrexate beyond psoriasis, with a focus on a wide range of inflammatory, vesiculobullous, and proliferative dermatological pathologies.

Unmet needs in treating itch: reaching beyond eczema

PURPOSE

Pruritus is an unpleasant sensation that creates the urge to scratch. In many chronic conditions, relentless pruritus and scratching perpetuates a vicious itch-scratch cycle. Uncontrolled itch can detrimentally affect quality of life and may lead to sleep disturbance, impaired concentration, financial burden, and psychological suffering. Recent strides have been made to develop guidelines and investigate new therapies to treat some of the most common severely pruritic conditions, however, a large group of diseases remains underrecognized and undertreated. The purpose of this article is to provide a comprehensive review of the challenges hindering the treatment of pruritus.

METHODS

An online search was performed using PubMed, Web of Science, Google Scholar, and ClinicalTrials.gov from 1994 to 2024. Included studies were summarized and assessed for quality and relevance in treating pruritus.

RESULTS

Several barriers to treating pruritus emerged, including variable presentation, objective measurement of itch, and identifying therapeutic targets. Itch associated with autoimmune conditions, connective tissue diseases, genodermatoses, cutaneous T-cell lymphoma, and pruritus of unknown origin were among the etiologies with the greatest unmet needs.

CONCLUSION

Treating pruritus poses many challenges and there are many itchy conditions that have no yet been addressed. There is an urgent need for large-scale controlled studies to investigate potential targets for these conditions and novel therapies.

Granzyme serine proteases in inflammation and rheumatic diseases

Granzymes (granule-secreted enzymes) are a family of serine proteases that have been viewed as redundant cytotoxic enzymes since their discovery more than 30 years ago. Predominantly produced by cytotoxic lymphocytes and natural killer cells, granzymes are delivered into the cytoplasm of target cells through immunological synapses in cooperation with the pore-forming protein perforin. After internalization, granzymes can initiate cell death through the cleavage of intracellular substrates. However, evidence now also demonstrates the existence of non-cytotoxic, pro-inflammatory, intracellular and extracellular functions that are granzyme specific. Under pathological conditions, granzymes can be produced and secreted extracellularly by immune cells as well as by non-immune cells. Depending on the granzyme, accumulation in the extracellular milieu might contribute to inflammation, tissue injury, impaired wound healing, barrier dysfunction, osteoclastogenesis and/or autoantigen generation.

The Oral-Lung Microbiome Axis in Connective Tissue Disease-Related Interstitial Lung Disease

Connective tissue disease-related interstitial lung disease (CTD-ILD) is a frequent and serious complication of CTD, leading to high morbidity and mortality. Unfortunately, its pathogenesis remains poorly understood; however, one intriguing contributing factor may be the microbiome of the mouth and lungs. The oral microbiome, which is a major source of the lung microbiome through recurrent microaspiration, is altered in ILD patients. Moreover, in recent years, several lines of evidence suggest that changes in the oral and lung microbiota modulate the pulmonary immune response and thus may play a role in the pathogenesis of ILDs, including CTD-ILD. Here, we review the existing data demonstrating oral and lung microbiota dysbiosis and possible contributions to the development of CTD-ILD in rheumatoid arthritis, Sjögren's syndrome, systemic sclerosis, and systemic lupus erythematosus. We identify several areas of opportunity for future investigations into the role of the oral and lung microbiota in CTD-ILD.

Novel Therapeutic Approaches in Connective Tissue Disease-Associated Interstitial Lung Disease

Connective tissue diseases (CTD) comprise a group of autoimmune diseases that can affect multiple organs in the body including the lungs. The most common form of pulmonary involvement is interstitial lung disease (ILD). CTD-associated ILD (CTD-ILD) can take one of several courses including nonprogressive, chronically progressive, or rapidly progressive. Chronically and rapidly progressive patterns are associated with increased mortality. Limited randomized controlled trial data are available for treatment of CTD-ILD, with most data coming from systemic sclerosis-related ILD. The current first-line treatment for all CTD-ILD is immunosuppression with consideration of antifibrotics, stem cell transplant, and lung transplant in progressive disease. In this article, we review data for ILD treatment options in systemic sclerosis, rheumatoid arthritis, myositis, and primary Sjögren's syndrome-related ILDs.

Cadherin-11 targeted cell-specific liposomes enabled skin fibrosis treatment by inducing apoptosis

Continuous and aberrant activation of myofibroblasts is the hallmark of pathological fibrosis (e.g., abnormal wound healing). The deposition of excessive extracellular matrix (ECM) components alters or increases the stiffness of tissue and primarily accounts for multiple organ dysfunctions. Among various proteins, Cadherin-11 (CDH11) has been reported to be overexpressed on myofibroblasts in fibrotic tissues. Anti-apoptotic proteins such as (B cell lymphoma-2) (BCL-2) are also upregulated on myofibroblasts. Therefore, we hypothesize that CDH11 could be a targeted domain for cell-specific drug delivery and targeted inhibition of BCL-2 to ameliorate the development of fibrosis in the skin. To prove our hypothesis, we have developed liposomes (LPS) conjugated with CDH11 neutralizing antibody (antiCDH11) to target cell surface CDH11 and loaded these LPS with a BCL-2 inhibitor, Navitoclax (NAVI), to induce apoptosis of CDH11 expressing fibroblasts. The developed LPS were evaluated for physicochemical characterization, stability, in vitro therapeutic efficacy using dermal fibroblasts, and in vivo therapeutic efficacy in bleomycin-induced skin fibrosis model in mice. The findings from in vitro and in vivo studies confirmed that selectivity of LPS was improved towards CDH11 expressing myofibroblasts, thereby improving therapeutic efficacy with no indication of adverse effects. Hence, this novel research work represents a versatile LPS strategy that exhibits promising potential for treating skin fibrosis.