Correlation of PMN elastase and PMN elastase-to-neutrophil ratio with disease activity in patients with myositis

Activity Prediction Modeling Based on a Combination of Growth Differentiation Factor 15 and Serum Biomarker Levels in Dermatomyositis and Polymyositis

AIMS

Growth differentiation factor 15 (GDF15) plays an important role in multiple inflammatory disorders. We aimed to analyze serum GDF15 levels in adult patients with idiopathic inflammatory myopathies (IIMs).

METHODS

Serum GDF15 levels were measured in 179 adult patients with IIMs and 76 healthy controls (HCs). The association between GDF15 levels and disease variables was analyzed using Spearman's rank correlation. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the discriminatory ability of GDF15 and the GDF15-to-lymphocyte ratio (GLR). Machine learning methods were applied to build predictive models.

RESULTS

GDF15 levels and GLR were significantly elevated in patients with adult IIMs than in HCs. Compared with patients in remission, both GDF15 and GLR were significantly higher in myositis patients in an active phase. GDF15 levels correlated positively with myositis disease activity indices and negatively correlated with lymphocyte and platelet counts. ROC curve analysis revealed that GDF15 levels and GLR outperformed muscle enzymes and distinguished well between patients with active disease and those in remission. Furthermore, even in the normal muscle enzyme group, GDF15 levels and GLR were also well-distinguished between patients with active disease and those in remission. Using machine learning, a logistic regression model of GDF15 combined with creatine kinase and lymphocyte count was constructed and had a reliable predictive value for disease activity.

CONCLUSIONS

GDF15, particularly GLR, was significantly correlated with disease activity in adult patients with IIMs. They could serve as useful biochemical markers for evaluating disease activity, monitoring disease progression, and guiding treatment in adult patients with IIMs.

Pathogenic role and clinical significance of neutrophils and neutrophil extracellular traps in idiopathic inflammatory myopathies

Idiopathic inflammatory myopathies (IIM) are a heterogeneous group of chronic autoimmune diseases characterized by muscle damage and extramuscular symptoms, including specific skin rash, arthritis, interstitial lung disease, and cardiac involvement. While the etiology and pathogenesis of IIM are not yet fully understood, emerging evidence suggests that neutrophils and neutrophil extracellular traps (NETs) have a role in the pathogenesis. Recent research has identified increased levels of circulating and tissue neutrophils as well as NETs in patients with IIM; these contribute to the activation of the type I and type II interferons pathway. During active IIM disease, myositis-specific antibodies are associated with the formation and incomplete degradation of NETs, leading to damage in the lungs, muscles, and blood vessels of patients. This review focuses on the pathogenic role and clinical significance of neutrophils and NETs in IIM, and it includes a discussion of potential targeted treatment strategies.

Autoimmune inflammatory myopathy biomarkers

The autoimmune inflammatory myopathy disease spectrum, commonly known as myositis, is a group of systemic diseases that mainly affect the muscles, skin and lungs. Biomarker assessment helps in understanding disease mechanisms, allowing for the implementation of precise strategies in the classification, diagnosis, and management of these diseases. This review examines the pathogenic mechanisms and highlights current data on blood and tissue biomarkers of autoimmune inflammatory myopathies.

Neutrophil diversity in inflammation and cancer

Neutrophils are the most abundant circulating leukocytes in humans and the first immune cells recruited at the site of inflammation. Classically perceived as short-lived effector cells with limited plasticity and diversity, neutrophils are now recognized as highly heterogenous immune cells, which can adapt to various environmental cues. In addition to playing a central role in the host defence, neutrophils are involved in pathological contexts such as inflammatory diseases and cancer. The prevalence of neutrophils in these conditions is usually associated with detrimental inflammatory responses and poor clinical outcomes. However, a beneficial role for neutrophils is emerging in several pathological contexts, including in cancer. Here we will review the current knowledge of neutrophil biology and heterogeneity in steady state and during inflammation, with a focus on the opposing roles of neutrophils in different pathological contexts.

Low serum level of citrullinated histone H3 in patients with dermatomyositis

OBJECTIVES

We aimed at analyzing the serum levels of citrullinated histone H3 (CitH3) in patients with dermatomyositis (DM) and their association with disease activity.

METHODS

Serum CitH3 levels were measured using enzyme-linked immunosorbent assays in serum samples obtained from 93 DM patients and 56 healthy controls (HCs). Receiver operating characteristic (ROC) curve analysis was performed to evaluate the discriminant capacity of CitH3 and other disease variables. The association between CitH3 and disease variables was analyzed using Pearson's rank correlation.

RESULTS

Serum CitH3 level was significantly lower in DM patients than in HCs (p < 0.001). The ROC curve analysis revealed that CitH3 strongly discriminated DM patients from HCs (area under the curve [AUC], 0.86), and a combination of CitH3 and the ratio of neutrophil to lymphocyte counts (NLR) showed a greater diagnostic value (AUC, 0.92). Serum CitH3 levels were markedly lower in DM patients with normal muscle enzyme levels than in HCs (all p < 0.001), and when compared to an elevated group, the CitH3 levels were comparable (all p > 0.05). The CitH3 levels showed no difference between DM in active and remission groups. However, in a paired test with 18 hospitalized DM patients, the CitH3 levels were higher in remission state than in active state. Moreover, the CitH3 levels showed no correlation with disease variables that were associated with the disease activity of DM.

CONCLUSIONS

Serum CitH3 level may serve as a useful biochemical marker for screening patients with DM from HCs, while its role in monitoring DM disease activity requires further research.

Neutrophil extracellular trap: A key player in the pathogenesis of autoimmune diseases

Numerous studies suggest that neutrophils might have a crucial role in the pathogenesis of systemic autoimmune diseases through neutrophil extracellular trap (NET) formation, production of pro-inflammatory cytokines, and organ destruction. NET components that are released into extracellular spaces can be considered autoantigens, which contribute to causing a break in self-tolerance. Subsequently, this leads to the development of autoimmune responses in predisposed individuals. Additionally, an imbalance between NET formation and NET degradation may prolong immune system contact with these modified autoantigens and enhance NET-induced tissue damage. In this review, we discuss the generation and clearance of the NET, as well as the role of NETosis in the pathogenesis of autoimmune disorders, including rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), anti-neutrophil cytoplasmic antibodies (ANCA)-associated vasculitis (AAV), multiple sclerosis (MS), psoriasis, antiphospholipid syndrome (APS), and Type-1 diabetes mellitus (T1DM).

Effects of Cannabidiol on Innate Immunity: Experimental Evidence and Clinical Relevance

Cannabidiol (CBD) is the main non-psychotropic cannabinoid derived from cannabis (Cannabis sativa L., fam. Cannabaceae). CBD has received approval by the Food and Drug Administration (FDA) and European Medicines Agency (EMA) for the treatment of seizures associated with Lennox-Gastaut syndrome or Dravet syndrome. However, CBD also has prominent anti-inflammatory and immunomodulatory effects; evidence exists that it could be beneficial in chronic inflammation, and even in acute inflammatory conditions, such as those due to SARS-CoV-2 infection. In this work, we review available evidence concerning CBD's effects on the modulation of innate immunity. Despite the lack so far of clinical studies, extensive preclinical evidence in different models, including mice, rats, guinea pigs, and even ex vivo experiments on cells from human healthy subjects, shows that CBD exerts a wide range of inhibitory effects by decreasing cytokine production and tissue infiltration, and acting on a variety of other inflammation-related functions in several innate immune cells. Clinical studies are now warranted to establish the therapeutic role of CBD in diseases with a strong inflammatory component, such as multiple sclerosis and other autoimmune diseases, cancer, asthma, and cardiovascular diseases.

Inflammatory myopathies and beyond: The dual role of neutrophils in muscle damage and regeneration

Skeletal muscle is one of the most abundant tissues of the human body and is responsible for the generation of movement. Muscle injuries can lead to severe disability. Skeletal muscle is characterized by an important regeneration capacity, which is possible due to the interaction between the myoblasts and immune cells. Neutrophils are fundamental as inducers of muscle damage and as promoters of the initial inflammatory response which eventually allows the muscle repair. The main functions of the neutrophils are phagocytosis, respiratory burst, degranulation, and the production of neutrophil extracellular traps (NETs). An overactivation of neutrophils after muscle injuries may lead to an expansion of the initial damage and can hamper the successful muscle repair. The importance of neutrophils as inducers of muscle damage extends beyond acute muscle injury and recently, neutrophils have become more relevant as part of the immunopathogenesis of chronic muscle diseases like idiopathic inflammatory myopathies (IIM). This heterogeneous group of systemic autoimmune diseases is characterized by the presence of muscle inflammation with a variable amount of extramuscular features. In IIM, neutrophils have been found to have a role as biomarkers of disease activity, and their expansion in peripheral blood is related to certain clinical features like interstitial lung disease (ILD) and cancer. On the other hand, low density granulocytes (LDG) are a distinctive subtype of neutrophils characterized by an enhanced production of NETs. These cells along with the NETs have also been related to disease activity and certain clinical features like ILD, vasculopathy, calcinosis, dermatosis, and cutaneous ulcers. The role of NETs in the immunopathogenesis of IIM is supported by an enhanced production and deficient degradation of NETs that have been observed in patients with dermatomyositis and anti-synthetase syndrome. Finally, new interest has arisen in the study of other phenotypes of LDG with a phenotype corresponding to myeloid-derived suppressor cells, which were also found to be expanded in patients with IIM and were related to disease activity. In this review, we discuss the role of neutrophils as both orchestrators of muscle repair and inducers of muscle damage, focusing on the immunopathogenesis of IIM.

Neutrophil extracellular traps in systemic autoimmune and autoinflammatory diseases

Systemic autoimmune diseases are characterized by the failure of the immune system to differentiate self from non-self. These conditions are associated with significant morbidity and mortality, and they can affect many organs and systems, having significant clinical heterogeneity. Recent discoveries have highlighted that neutrophils, and in particular the neutrophil extracellular traps that they can release upon activation, can have central roles in the initiation and perpetuation of systemic autoimmune disorders and orchestrate complex inflammatory responses that lead to organ damage. Dysregulation of neutrophil cell death can lead to the modification of autoantigens and their presentation to the adaptive immune system. Furthermore, subsets of neutrophils that seem to be more prevalent in patients with systemic autoimmune disorders can promote vascular damage and increased oxidative stress. With the emergence of new technologies allowing for improved assessments of neutrophils, the complexity of neutrophil biology and its dysregulation is now starting to be understood. In this Review, we provide an overview of the roles of neutrophils in systemic autoimmune and autoinflammatory diseases and address putative therapeutic targets that may be explored based on this new knowledge.

Cardiovascular Risk in Myositis Patients Compared to the General Population: Preliminary Data From a Single-Center Cross-Sectional Study

Background

Idiopathic inflammatory myopathies (IIM) are associated with systemic inflammation, limited mobility, and glucocorticoid therapy, all of which can lead to metabolism disturbances, atherogenesis, and increased cardiovascular (CV) risk. The aim of this study was to assess the CV risk in IIM patients and healthy controls (HC), and its association with disease-specific features.

Methods

Thirty nine patients with IIM (32 females; mean age 56; mean disease duration 4.8 years; dermatomyositis: n = 16, polymyositis: n = 7, immune-mediated necrotizing myopathy: n = 8, anti-synthetase syndrome: n = 8) and 39 age-/sex-matched HC (32 females, mean age 56) without rheumatic diseases were included. In both groups, subjects with a history of CV disease (angina pectoris, myocardial infarction, cerebrovascular, and peripheral arterial vascular events) were excluded. Muscle involvement, disease activity, and tissue damage were evaluated (Manual Muscle Test-8, Myositis Intention to Treat Activity Index, Myositis Damage Index). Comorbidities and current treatment were recorded. All participants underwent examinations of carotid intima-media thickness (CIMT), pulse wave velocity (PWV), ankle-brachial index (ABI), and body composition (by densitometry and bioelectric impedance). The risk of fatal CV events was evaluated by the Systematic COronary Risk Evaluation (SCORE, charts for the European population) and its modifications.

Results

Compared to HC, there was no significant difference in IIM patients regarding blood pressure, ABI, PWV, CIMT, and the risk of fatal CV events by SCORE or SCORE2, or subclinical atherosclerosis (CIMT, carotid plaques, ABI, and PWV). The calculated CV risk scores by SCORE, SCORE2, and SCORE multiplied by the coefficient 1.5 (mSCORE) were reclassified according to the results of carotid plaque presence and CIMT; however, none of them was demonstrated to be significantly more accurate. Other significant predictors of CV risk in IIM patients included age, disease duration and activity, systemic inflammation, lipid profile, lean body mass, and blood pressure.

Conclusions

No significant differences in CV risk factors between our IIM patients and HC were observed. However, in IIM, CV risk was associated with age, disease duration, duration of glucocorticoid therapy, lipid profile, and body composition. None of the currently available scoring tools (SCORE, SCORE2, mSCORE) used in this study seems more accurate in estimating CV risk in IIM.