Treatment with imatinib results in reduced IL-4-producing T cells, but increased CD4(+) T cells in the broncho-alveolar lavage of patients with systemic sclerosis

Decreased Th1 Cells and Increased Th2 Cells in Peripheral Blood Are Associated with Idiopathic Inflammatory Myopathies Patients with Interstitial Lung Disease

Interstitial lung disease (ILD) is a highly fatal manifestation of idiopathic inflammatory myopathies (IIMs). Th cells play important roles in the initiation of ILD. Here, we investigated the clinical significance of peripheral blood Th cells in IIMs-ILD patients. Eleven healthy controls (HC) and 53 patients diagnosed with IIMs were included, including 30 with ILD (IIMs-ILD) and 23 without ILD (IIMs-non-ILD). Circulating Th1, Th2, Th17, and Treg cells were examined by flow cytometry, and their correlation with clinical and laboratory findings was analyzed by Spearman's correlation and logistic regression. The proportion of Th1 cells decreased and Th2 cells increased in IIMs-ILD compared with IIMs-non-ILD (median (quartile): 2.99 (1.59-5.39) vs. 6.91 (3.48-10.04), p < 0.001; 2.67 (1.79-4.67) vs. 1.62 (0.85-2.66), p = 0.006) and correlated with disease activity. The Th1-cell proportion decreased in anti-MDA5 antibody-positive patients, while the Th2 cell proportion increased in patients with nonspecific interstitial pneumonia compared with IIMs-non-ILD (2.66 (1.06-4.35) vs. 6.91 (3.48-10.04), p = 0.002; 3.09 (2.03-5.72) vs. 1.62 (0.85-2.66), p = 0.016). Univariate analysis showed that a lower Th1 proportion, higher Th2 proportion increased, lower CK level, positivity for ARS, or anti-Ro52 antibodies (OR = 0.7122; OR = 1.679; OR = 0.9993; OR = 9.188; and OR = 6.161, respectively) were associated with the occurrence of ILD in IIMs patients. Decreased Th1 cells and elevated Th2 cells in peripheral blood may be involved in the pathogenesis of ILD in IIMs patients and have different effects on different serological and imaging subtypes.

Therapeutic Options for Systemic Sclerosis: Current and Future Perspectives in Tackling Immune-Mediated Fibrosis

Systemic sclerosis (SSc) is a severe auto-immune, rheumatic disease, characterized by excessive fibrosis of the skin and visceral organs. SSc is accompanied by high morbidity and mortality rates, and unfortunately, few disease-modifying therapies are currently available. Inflammation, vasculopathy, and fibrosis are the key hallmarks of SSc pathology. In this narrative review, we examine the relationship between inflammation and fibrosis and provide an overview of the efficacy of current and novel treatment options in diminishing SSc-related fibrosis based on selected clinical trials. To do this, we first discuss inflammatory pathways of both the innate and acquired immune systems that are associated with SSc pathophysiology. Secondly, we review evidence supporting the use of first-line therapies in SSc patients. In addition, T cell-, B cell-, and cytokine-specific treatments that have been utilized in SSc are explored. Finally, the potential effectiveness of tyrosine kinase inhibitors and other novel therapeutic approaches in reducing fibrosis is highlighted.

Efficacy and safety of imatinib mesylate in systemic sclerosis. A systematic review and meta-analysis

OBJECTIVES

To synthetize the available evidence concerning efficacy and safety of imatinib mesylate, a tyrosine kinase inhibitor, in systemic sclerosis (SSc).

METHODS

A systematic search following the PRISMA-statement in PubMed/MEDLINE, Cochrane CENTRAL, and Web of Science databases up to 7 February 2020 was conducted. Considering the substantial heterogeneity expected, a random-effects model to pool data from selected studies was adopted.

RESULTS

After a treatment period ranging from 6 to 12 months, the pooled analysis revealed that imatinib mesylate significantly improved modified Rodnan skin score (mRSS) (mean difference [MD] = -3.091, 95%CI -6.081 to -0.102, p = 0.043), whereas health-related assessment questionnaire (HAQ) remains unchanged (-0.096; 95 CI -0.197 to -0.006). Data regarding change in pulmonary function tests were insufficiently consistent to be considered eligible for meta-analysis. Finally, regarding safety, the authors found a pooled dropout rate due to all adverse events of 22% and a rate of serious adverse events of 17%.

CONCLUSION

The significant change within the range of clinical relevance of mRSS suggests the possible use of imatinib mesylate in SSc, whereas it is still not possible to draw firm conclusions regarding the efficacy of the drug on lung involvement. Specifically designed and powered studies are needed to investigate imatinib mesylate therapy in SSc.

Etiology, Risk Factors, and Biomarkers in Systemic Sclerosis with Interstitial Lung Disease

Systemic sclerosis (SSc) is a complex, multiorgan, autoimmune disease. Lung fibrosis occurs in ∼80% of patients with SSc; 25% to 30% develop progressive interstitial lung disease (ILD). The pathogenesis of fibrosis in SSc-associated ILD (SSc-ILD) involves cellular injury, activation/differentiation of mesenchymal cells, and morphological/biological changes in epithelial/endothelial cells. Risk factors for progressive SSc-ILD include older age, male sex, degree of lung involvement on baseline high-resolution computed tomography imaging, reduced Dl_CO, and reduced FVC. SSc-ILD does not share the genetic risk architecture observed in idiopathic pulmonary fibrosis (IPF), with key risk factors yet to be identified. Presence of anti-Scl-70 antibodies and absence of anti-centromere antibodies indicate increased likelihood of progressive ILD. Elevated levels of serum Krebs von den Lungen-6 and C-reactive protein are both associated with SSc-ILD severity and predict SSc-ILD progression. A promising prognostic indicator is serum chemokine (C-C motif) ligand 18. SSc-ILD shares similarities with IPF, although clear differences exist. Histologically, a nonspecific interstitial pneumonia pattern is commonly observed in SSc-ILD, whereas IPF is defined by usual interstitial pneumonia. The course of SSc-ILD is variable, ranging from minor, stable disease to a progressive course, whereas all patients with IPF experience progression of disease. Although appropriately treated patients with SSc-ILD have better chances of stabilization and survival, a relentlessly progressive course, akin to IPF, is seen in a minority. Better understanding of cellular and molecular pathogenesis, genetic risk, and distinctive features of SSc-ILD and identification of robust prognostic biomarkers are needed for optimal disease management.

The role of interleukin-4 in rheumatic diseases

Rheumatism is a group of diseases, most of which are autoimmune diseases, that violate joints, bones, muscles, blood vessels and related soft tissue. As is well known, cytokines play a role in the pathogenesis of several rheumatic diseases, such as rheumatoid arthritis, spondyloarthritides, and systemic lupus erythematosus. Recently, the role of interleukin-4 (IL-4), which may participate in the mechanism of rheumatism, have been discovered. It is reported that IL-4 takes part in the regulation of T cell activation, differentiation, proliferation, and survival of different T cell types. IL-4 also has an immunomodulatory effect on B cells, mast cells, macrophages, and many cell types. A review of the literature on functions of IL-4 in rheumatic diseases is presented.

pDCs in lung and skin fibrosis in a bleomycin-induced model and patients with systemic sclerosis

Fibrosis is the end result of most inflammatory conditions, but its pathogenesis remains unclear. We demonstrate that, in animals and humans with systemic fibrosis, plasmacytoid DCs (pDCs) are unaffected or are reduced systemically (spleen/peripheral blood), but they increase in the affected organs (lungs/skin/bronchoalveolar lavage). A pivotal role of pDCs was shown by depleting them in vivo, which ameliorated skin and/or lung fibrosis, reduced immune cell infiltration in the affected organs but not in spleen, and reduced the expression of genes and proteins implicated in chemotaxis, inflammation, and fibrosis in the affected organs of animals with bleomycin-induced fibrosis. As with animal findings, the frequency of pDCs in the lungs of patients with systemic sclerosis correlated with the severity of lung disease and with the frequency of CD4+ and IL-4+ T cells in the lung. Finally, treatment with imatinib that has been reported to reduce and/or prevent deterioration of skin and lung fibrosis profoundly reduced pDCs in lungs but not in peripheral blood of patients with systemic sclerosis. These observations suggest a role for pDCs in the pathogenesis of systemic fibrosis and identify the increased trafficking of pDCs to the affected organs as a potential therapeutic target in fibrotic diseases.

Use of multitarget tyrosine kinase inhibitors to attenuate platelet-derived growth factor signalling in lung disease

Platelet-derived growth factors (PDGFs) and their receptors (PDGFRs) play a fundamental role in the embryonic development of the lung. Aberrant PDGF signalling has been documented convincingly in a large variety of pulmonary diseases, including idiopathic pulmonary arterial hypertension, lung cancer and lung fibrosis. Targeting PDGF signalling has been proven to be effective in these diseases. In clinical practice, the most effective way to block PDGF signalling is to inhibit the activity of the intracellular PDGFR kinases. Although the mechanism of action of such drugs is not specific for PDGF signalling, the medications have a broad therapeutic index that allows clinical use. The safety profile and therapeutic opportunities of these and future medications that target PDGFs and PDGFRs are reviewed.

An increasing role for PDGF signalling inhibitors in clinical trials for the treatment of various pulmonary diseaseshttp://ow.ly/buaI30f9HcN

Role of anti-inflammatory cytokines IL-4 and IL-13 in systemic sclerosis

OBJECTIVE

The aim of this paper is to review the anti-inflammatory cytokines IL-4 and IL-13 and their receptor signals; we discuss new insight into their possible roles in systemic sclerosis (SSc) and their overlapping function in SSc.

INTRODUCTION

SSc is a connective tissue disease characterized by fibrosis. The exact etiology of SSc is unknown, and no therapy has been proved effective in modifying its course. Recently the roles of IL-4 and IL-13 in the development of SSc have been extensively considered. The possible roles of IL-4 and IL-13, especially their overlapping function, in SSc are not well documented.

METHODS

A literature survey was performed using a PubMed database search to gather complete information regarding IL-4 and IL-13 and their role in inflammation.

RESULTS AND CONCLUSIONS

The participation of complex pathways of IL-4 and IL-13 in the process of inflammation and fibrosis action in SSc is still not very clear, and some pathogenesis of regulation found in vitro needs to be further proved. There is still more work which could be done to achieve useful developments with therapeutic benefit in SSc.

Cellular mechanisms of tissue fibrosis. 8. Current and future drug targets in fibrosis: focus on Rho GTPase-regulated gene transcription

Tissue fibrosis occurs with excessive extracellular matrix deposition from myofibroblasts, resulting in tissue scarring and inflammation. It is driven by multiple mediators, such as the G protein-coupled receptor ligands lysophosphatidic acid and endothelin, as well as signaling by transforming growth factor-β, connective tissue growth factor, and integrins. Fibrosis contributes to 45% of deaths in the developed world. As current therapeutic options for tissue fibrosis are limited and organ transplantation is the only effective treatment for end-stage disease, there is an imminent need for efficacious antifibrotic therapies. This review discusses the various molecular pathways involved in fibrosis. It highlights the Rho GTPase signaling pathway and its downstream gene transcription output through myocardin-related transcription factor and serum response factor as a convergence point for targeting this complex set of diseases.

Does the small tyrosine kinase inhibitor Imatinib mesylate counteract diabetes by affecting pancreatic islet amyloidosis and fibrosis?

INTRODUCTION

The small tyrosine kinase inhibitor Imatinib Mesylate (Gleevec) protects against diabetes, but it is not known how.

AREAS COVERED

It has been suggested that islet amyloid and fibrotic deposits promote beta-cell failure and death, leading to Type-2 diabetes. As Imatinib is known to possess anti-fibrotic/amyloid properties, in for example systemic sclerosis and mouse models for Alzheimer's disease, the present review will discuss the possibility that Imatinib acts, at least in part, by ameliorating islet hyalinization and its consequences in the pathogenesis of Type-2 diabetes.

EXPERT OPINION

A better understanding of how Imatinib counteracts Type-2 diabetes will possibly help to clarify the pathogenic role of islet amyloid and fibrosis, and hopefully lead to improved treatment of the disease.

Therapeutic inhibition of tyrosine kinases in systemic sclerosis: a review of published experience on the first 108 patients treated with imatinib

OBJECTIVE

Experimental and clinical evidence suggest a therapeutic role for the tyrosine kinase inhibitor imatinib in fibrosing conditions. We evaluated published data on the safety and efficacy of imatinib for patients with systemic sclerosis (SSc), a severe autoimmune disease with significant morbidity and mortality.

METHODS

A careful search for all original articles and abstracts on the use of imatinib in SSc published in English from 2008 through February 2012 was performed. Two additional patients from our center are also described.

RESULTS

Five small observational clinical trials on the use of imatinib in severe SSc have been conducted and case reports and small series of refractory to current approaches patients have been reported, adding to a total of 108 patients having received this drug to date. In most of these patients imatinib was given for skin or pulmonary fibrosis. Encouraging results were reported in 3 of 4 studies, whereas the fifth study was prematurely terminated for safety reasons. Overall, clinical results are highly variable, ranging from ineffective or toxic responses to extremely encouraging clinical improvements in some severely ill patients. These discrepancies could partly reflect imatinib-related safety issues, in particular, SSc patients or idiosyncratic resistance to imatinib, as happens in chronic myelogenous leukemia and gastrointestinal stromal tumors, the drug's approved indications.

CONCLUSIONS

The limited available experience suggests that imatinib could be considered as an individualized treatment approach in severe SSc and underscores the need to identify markers for selecting particular patients, who will safely respond to therapeutic inhibition of tyrosine kinases.

T cells in systemic sclerosis: a reappraisal

SSc is an autoimmune disease characterized by inflammation and extracellular matrix deposition that ultimately leads to loss of organ function. T cells appear to play a prominent role in its pathogenesis. The evidence for this comes from their being at the site of fibrosis, their activated phenotype and alteration in their number and frequency in peripheral blood. This review examines the role of T cells in the pathogenesis of SSc and specifically examines the key soluble profibrotic mediators (IL-4, IL-6, IL-13) secreted by Th2 cells and their interactions with fibroblasts that deposit excess extracellular matrix leading to fibrosis. We finally examine possible therapeutic options in targeting T-cell mediators to disrupt the cellular interactions between T cells and fibroblasts that serve to drive the fibrotic response. One of the factors driving fibrosis is IL-6 and this can be neutralized in vivo not only to limit IL-6-driven tissue fibrosis but concomitantly to suppress switching of Tregs to Th17 T cells that will provide more IL-6, thus perpetuating the fibrosis. Taken together, these data implicate the role of T cells in SSc and suggest that Th2-polarized T cells and the fibrotic mediators subsequently released directly induce fibrosis. Targeting such cytokines may be therapeutic not only in SSc but more generally in diseases where fibrosis is directed by inflammatory signals.