A high level of serum neopterin is associated with rapidly progressive interstitial lung disease and reduced survival in dermatomyositis

Liver Involvement is Associated with Higher Risk of Rapidly Progressive Interstitial Lung Disease and Mortality in Anti-Melanoma Differentiation-Associated Gene 5 Antibody- Positive Dermatomyositis

Purpose

This study aimed to assess liver involvement and investigate its correlation with rapidly progressive interstitial lung disease (RP-ILD) and mortality in anti-melanoma differentiation-associated gene 5 antibody-positive (anti-MDA5 positive) DM patients.

Patients and Methods

This retrospective study included 159 patients diagnosed with anti-MDA5 positive DM or anti-synthetase syndrome (ASyS). Clinical features and laboratory findings were compared between patients with anti-MDA5 positive DM and patients with ASyS. In the anti-MDA5 positive DM cohort, clinical features and laboratory findings between patients with liver involvement and without liver involvement were further compared. The effects of liver involvement on the overall survival (OS) and development of RP-ILD were also analyzed using Kaplan-Meier method and Cox regression analysis.

Results

Levels of serum aspartate aminotransferase (AST), alanine transaminase (ALT), γ-glutamyl transferase (γGT) and alkaline phosphatase (ALP) were all significantly higher in patients with anti-MDA5 positive DM than those in patients with ASyS. In our cohort of anti-MDA5 positive DM patents, 31 patients (34.4%) were complicated with liver involvement. Survival analysis revealed that serum ferritin >1030.0 ng/mL (p<0.001), ALT >103.0 U/l (p<0.001), AST >49.0 U/l (p<0.001), γGT >82.0 U/l (p<0.001), ALP >133.0 U/l (p<0.001), lactate dehydrogenase (LDH)>474.0 U/l (p<0.001), plasma albumin (ALB) <35.7 g/l (p<0.001) and direct bilirubin (DBIL) >2.80 μmol/l (p=0.002) predicted poor prognosis. The incidence of RP-ILD increased remarkably in patients with liver involvement compared to patients without liver involvement (58.1% vs 22.0%, p=0.001). Multivariate analysis revealed that elevated serum ALT level was an independent risk factor for mortality (HR 6.0, 95% CI 2.3, 16.2, p<0.001) and RP-ILD (HR 5.9, 95% CI 2.2, 15.9, p<0.001) in anti-MDA5 positive DM patents.

Conclusion

Liver involvement is common in patients with anti-MDA5 positive DM. Elevated serum ALT level was an independent risk factor for RP-ILD and mortality in patients with anti-MDA5 positive DM.

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.

Anti-MDA5 antibody-positive dermatomyositis: pathogenesis and clinical progress

Anti-melanoma differentiation-associated protein 5 (MDA5) antibody-positive dermatomyositis (MDA5-DM) is a subtype of dermatomyositis. Although the aetiology and pathology remain unclear, increasing evidence suggests that viral infection is a potential trigger of MDA5-DM. Multiple factors, including T cells, B cells, neutrophils and macrophages, are implicated in the pathophysiology of MDA5-DM. Distinctive skin rashes, rapidly progressive interstitial lung disease, peripheral lymphopenia and elevated serum ferritin levels are the most prominent clinical and laboratory features of MDA5-DM. Concomitant infection is a common complication of MDA5-DM. The proper evaluation of patients with MDA5-DM requires knowledge of the disease heterogeneity and clinical course variability. Several biomarkers, including serum levels of anti-MDA5 antibodies and biomarkers related to macrophage activation, have been identified as useful tools for monitoring disease activity and prognosis. MDA5-DM shows a poor response to conventional glucocorticoid and immunosuppressant therapy and has a poor overall prognosis. Therefore, there is an urgent need to explore the key pathogenic mechanisms of MDA5-DM and develop novel therapeutic options for patients. This Review discusses recent clinical progress and pathogenic findings of MDA5-DM.

Clinical features of macrophage activation syndrome in adult dermatomyositis: A single-center retrospective case-control study

BACKGROUND

Little is known about the features of macrophage activation syndrome (MAS) in dermatomyositis, especially the association between rapidly progressive interstitial lung disease (RP-ILD) and MAS.

OBJECTIVE

To determine the characteristics of MAS in patients with dermatomyositis and their association with RP-ILD.

METHODS

This was a retrospective cohort study of 201 dermatomyositis patients at the First Affiliated Hospital of Zhejiang University over a 10-year period.

RESULTS

A total of 22 (10.9%) patients were diagnosed with MAS. The rate of RP-ILD was significantly higher in patients with MAS than in those without MAS (81.8% vs. 17.4%, respectively, p < .001). Multivariate analysis indicated that RP-ILD (p = .019), ferritin level > 1685 ng/mL (p = .007) and hemoglobin < 100 g/L (p = .001) were independent risk factors for MAS. Furthermore, RP-ILD patients with MAS presented more cardiac injury (50.0% vs. 13.3%, respectively, p < .009), central nervous system dysfunction (42.8% vs. 3.4%, respectively, p < .001) and hemorrhage (38.9% vs. 3.3%, respectively, p = .003) than RP-ILD patients without MAS. The 90-day cumulative survival rate for patients with MAS was significantly lower than for those without MAS (18.2% vs. 82.1%, respectively, p < .001).

CONCLUSION

MAS was a common and fatal complication of dermatomyositis in our cohort. MAS is closely related to RP-ILD in patients with dermatomyositis. When RP-ILD is present in dermatomyositis patients with abnormal laboratory findings, such as cytopenia and hyperferritinemia, the presence of MAS should be considered.

Current Biomarker Strategies in Autoimmune Neuromuscular Diseases

Inflammatory neuromuscular disorders encompass a diverse group of immune-mediated diseases with varying clinical manifestations and treatment responses. The identification of specific biomarkers has the potential to provide valuable insights into disease pathogenesis, aid in accurate diagnosis, predict disease course, and monitor treatment efficacy. However, the rarity and heterogeneity of these disorders pose significant challenges in the identification and implementation of reliable biomarkers. Here, we aim to provide a comprehensive review of biomarkers currently established in Guillain-Barré syndrome (GBS), chronic inflammatory demyelinating polyneuropathy (CIDP), myasthenia gravis (MG), and idiopathic inflammatory myopathy (IIM). It highlights the existing biomarkers in these disorders, including diagnostic, prognostic, predictive and monitoring biomarkers, while emphasizing the unmet need for additional specific biomarkers. The limitations and challenges associated with the current biomarkers are discussed, and the potential implications for disease management and personalized treatment strategies are explored. Collectively, biomarkers have the potential to improve the management of inflammatory neuromuscular disorders. However, novel strategies and further research are needed to establish clinically meaningful biomarkers.

IFN-γ: An overlooked cytokine in dermatomyositis with anti-MDA5 antibodies

Dermatomyositis with anti-melanoma differentiation-associated gene 5 antibody (anti-MDA5 DM) is a rare autoimmune disease, often complicated by life-threatening, rapidly progressive interstitial lung disease. Additional manifestations of the disease include skin lesions, vascular abnormalities, joints and muscles pain. Despite its clinical significance, the pathogenesis of anti-MDA5 DM remains largely unknown. Currently, the disease is perceived as driven by type I interferon (IFN) whose expression is increased in most of the patients. Importantly, the regulation of IFN-γ is also altered in anti-MDA5 DM as evidenced by the presence of IFN-γ positive histiocytes in the lungs of patients, and the identification of autoantibodies that directly stimulate the production of IFN-γ by mononuclear cells. This review critically examines the pathogenesis of the disease, shedding light on recent findings that emphasize a potential role of IFN-γ. A novel conceptual framework is proposed, which integrates the molecular mechanisms altering IFN-γ regulation in anti-MDA5 DM with the known functional effects of IFN-γ on key tissues affected during the disease, such as the lungs, skin, and vessels. Understanding the precise role and relevance of IFN-γ in the pathogenesis of the disease will not only enhance the selection of available therapies for anti-MDA5 DM patients but also pave the way for the development of new therapeutic approaches targeting the altered molecular pathways.

A systematic review and meta-analysis of neopterin in rheumatic diseases

Introduction

Novel biomarkers of inflammation and oxidative stress might enhance the early recognition, management, and clinical outcomes of patients with rheumatic diseases (RDs). We assessed the available evidence regarding the pathophysiological role of neopterin, the oxidation product of 7,8-dihydroneopterin, a pteridine generated in macrophages activated by interferon-γ, by conducting a systematic review and meta-analysis of studies reporting its concentrations in biological fluids in RD patients and healthy controls.

Methods

We searched electronic databases for relevant articles published between inception and 31 August 2023. The risk of bias and the certainty of evidence were assessed using the Joanna Briggs Institute Critical Appraisal Checklist and the Grades of Recommendation, Assessment, Development and Evaluation Working Group system, respectively.

Results

In 37 studies, when compared to healthy controls, RD patients had significantly higher concentrations of neopterin both in plasma or serum (standard mean difference, SMD=1.31, 95% CI 1.01 to 1.61; p<0.001; moderate certainty of evidence) and in the urine (SMD=1.65, 95% CI 0.86 to 2.43, p<0.001; I2 = 94.2%, p<0.001; low certainty of evidence). The results were stable in sensitivity analysis. There were non-significant associations in meta-regression and subgroup analysis between the effect size and age, male to female ratio, year of publication, sample size, RD duration, C-reactive protein, erythrocyte sedimentation rate, specific type of RD, presence of connective tissue disease, analytical method used, or biological matrix investigated (plasma vs. serum). By contrast, the effect size was significantly associated with the geographical area in studies assessing serum or plasma and with the type of RD in studies assessing urine.

Discussion

Pending additional studies that also focus on early forms of disease, our systematic review and meta-analysis supports the proposition that neopterin, a biomarker of inflammation and oxidative stress, can be useful for the identification of RDs. (PROSPERO registration number: CRD42023450209).

Systematic review registration

PROSPERO, identifier CRD42023450209.

Assessment of serum neopterin and calprotectin as biomarkers for subclinical inflammation in patients with familial Mediterranean fever

BACKGROUND

Familial Mediterranean fever (FMF) is the most common autoinflammatory disease characterized by short, repeated, and self-limiting attacks of fever and serositis. Subclinical inflammation can persist in the periods with no symptoms and result in amyloidosis even with colchicine treatment. Neopterin and calprotectin have been considered essential players in inflammation and immune response.

AIM

The study was aimed to measure serum levels of neopterin and calprotectin in patients with FMF in the attack-free period.

METHODS

A total of 160 participants were recruited from the rheumatology department in this single-center, case-control study. Individuals having the inclusion criteria were divided into healthy controls (n = 80) and FMF (n = 80). The laboratory data were acquired from the electronic registration database. Serum calprotectin and neopterin were measured with ELISA test kits. FMF patients and healthy controls' laboratory findings were compared.

RESULTS

FMF patients' serum red cell distribution width (RDW), calprotectin, and neopterin values were significantly higher compared to healthy controls. There were no statistically significant differences between calprotectin and neopterin regarding gender, family history, and colchicine response of the FMF patients.

CONCLUSIONS

Calprotectin, neopterin, and RDW can be valuable marker candidates to be used in the follow-up of subclinical inflammation in FMF patients.

Clinically Relevant Biomarkers in Connective Tissue Disease-Associated Interstitial Lung Disease

Interstitial lung disease (ILD) complicates connective tissue disease (CTD) with variable incidence and is a leading cause of death in these patients. To improve CTD-ILD outcomes, early recognition and management of ILD is critical. Blood-based and radiologic biomarkers that assist in the diagnosis CTD-ILD have long been studied. Recent studies, including -omic investigations, have also begun to identify biomarkers that may help prognosticate such patients. This review provides an overview of clinically relevant biomarkers in patients with CTD-ILD, highlighting recent advances to assist in the diagnosis and prognostication of CTD-ILD.

Neopterin, the Cell-Mediated Immune Response Biomarker, in Inflammatory Periodontal Diseases: A Narrative Review of a More than Fifty Years Old Biomarker

Neopterin is a biomarker of the activation of cellular immunity. The purpose of this review is to summarise neopterin metabolism, methods of its detection, and its role in inflammation, focusing on periodontal inflammatory diseases. This derivative of guanosine is a non-enzymatic product of 7,8-dihydroneopterin oxidation caused by free radicals which protect activated macrophages from oxidative stress. Various methods, usually based on enzyme-linked immunosorbent essay, high-performance liquid chromatography, or radioimmunoassay were developed for the isolation of neopterin. A wide spectrum of diseases and conditions are known to affect neopterin levels, including cardiovascular, bacterial, viral, and degenerative diseases, as well as malignant tumours. Neopterin levels were found to increase in subjects with periodontitis, especially when the oral fluid and gingival crevicular fluid were evaluated. These findings confirm the role of activated macrophages and cellular immunity in periodontal inflammatory diseases. The gingival crevicular fluid and the oral fluid appear to be the most valuable biologic fluids for the evaluation of neopterin levels in periodontitis. For gingival crevicular fluid, neopterin can be determined as the concentration or the so-called total amount. Nonsurgical periodontal treatment was associated with a decrease in neopterin levels, but an increase was also reported, suggesting the possible role of macrophages in the resolution of the periodontal lesion.

Peripheral lymphocyte count defines the clinical phenotypes and prognosis in patients with anti-MDA5-positive dermatomyositis

OBJECTIVE

To explore the role of peripheral lymphocyte count in phenotyping and prognosis prediction in dermatomyositis (DM) patients with anti-MDA5 antibodies.

METHODS

In total, 1669 patients with idiopathic inflammatory myopathy (IIM) were retrospectively enrolled. Clinical characteristics and prognosis of patients with anti-MDA5+ DM were analyzed in association with peripheral lymphocyte counts and clusters determined by unsupervised machine learning.

RESULTS

The peripheral lymphocyte count was significantly lower in the anti-MDA5+ DM group (N = 421) than in the other IIM serotype groups. The anti-MDA5+ DM patients were divided into three groups; the severe lymphopenia group had skin ulcers and rapidly progressive interstitial lung disease (RP-ILD); patients with a normal lymphocyte count had a younger age of onset, more frequent arthritis, and normal serum ferritin levels, whereas mild lymphopenia group showed a moderate increase of serum ferritin and intermediate incidence of RP-ILD. Survival analysis revealed that the 3- and 6-month mortality rates were significantly higher in the severe lymphopenia group (29.0% and 42.1%, respectively) than in the mild lymphopenia group and normal lymphocyte count group (p value <0.001). Consistently, unsupervised machine learning identified three similar groups; the arthritis cluster shows the highest lymphocyte counts and best prognosis; the RP-ILD cluster presents the lowest peripheral lymphocyte, high incidence of RP-ILD, and poor prognosis; the typical DM rash cluster had a moderate peripheral lymphocyte count and an intermediate prognosis.

CONCLUSIONS

Lymphopenia is a unique manifestation of anti-MDA5+ DM. Peripheral lymphocyte count can define clinical phenotypes and predict prognosis in anti-MDA5+ DM.

Targeting intracellular pathways in idiopathic inflammatory myopathies: A narrative review

In recent decades, several pieces of evidence have drawn greater attention to the topic of innate immunity, in particular, interferon (IFN) and Interleukin 6 in the pathogenesis of idiopathic inflammatory myopathies (IIM). Both of these molecules transduce their signal through a receptor coupled with Janus kinases (JAK)/signal transducer and activator of transcription proteins (STAT). In this review, we discuss the role of the JAK/STAT pathway in IIM, evaluate a possible therapeutic role for JAK inhibitors in this group of diseases, focusing on those with the strongest IFN signature (dermatomyositis and antisynthetase syndrome).

Predictors of progression in idiopathic inflammatory myopathies with interstitial lung disease

The idiopathic inflammatory myopathies (IIMs) are a group of connective tissue diseases that afect multiple organ systems, including the lungs. Interstitial lung disease (ILD) is the most common and heterogeneous complication of IIMs, with its degree ranging from mild to fatal. Thus, it is critical to identify clinical features and validated biomarkers for predicting disease progression and prognosis, which could be beneficial for therapy adjustment. In this review, we discuss predictors for rapid progression of IIM-ILD and propose guidance for disease monitoring and implications of therapy. Systematic screening of myositis-specific antibodies, measuring serum biomarker levels, pulmonary function tests, and chest high-resolution computer tomography will be beneficial for the evaluation of disease progression and prognosis.

Roles of biomarkers in anti-MDA5-positive dermatomyositis, associated interstitial lung disease, and rapidly progressive interstitial lung disease

BACKGROUND

Anti-melanoma differentiation-associated gene 5 (MDA5)-positive dermatomyositis (MDA5⁺ DM) is significantly associated with interstitial lung disease (ILD), especially rapidly progressive ILD (RPILD) due to poor prognosis, resulting in high mortality rates. However, the pathogenic mechanism of MDA5⁺ DM-RPILD is unclear. Although some MDA5⁺ DM patients have a chronic course of ILD, many do not develop RPILD. Therefore, the related biomarkers for the early diagnosis, disease activity monitoring, and prediction of the outcome of RPILD in MDA5⁺ DM patients should be identified. Blood-based biomarkers are minimally invasive and can be easily detected.

METHODS

Recent relative studies related to blood biomarkers in PubMed were reviewed.

RESULTS

An increasing number of studies have demonstrated that dysregulated expression of blood biomarkers related to ILD such as ferritin, Krebs von den Lungen-6 (KL-6), surfactant protein-D (SP-D), and cytokines, and some tumor markers in MDA5⁺ DM may provide information in disease presence, activity, treatment response, and prognosis. These studies have highlighted the great potentials of blood biomarker values for MDA5⁺ DM-ILD and MDA5⁺ DM-RPILD. This review provides an overview of recent studies related to blood biomarkers, besides highlighted protein biomarkers, including antibody (anti-MDA5 IgG subclasses and anti-Ro52 antibody), genetic (exosomal microRNAs and neutrophil extracellular traps related to cell-free DNA), and immune cellular biomarkers in MDA5⁺ DM, MDA5⁺ DM-ILD, and MDA5⁺ DM-RPILD patients, hopefully elucidating the pathogenesis of MDA5⁺ DM-ILD and providing information on the early diagnosis, disease activity monitoring, and prediction of the outcome of the ILD, especially RPILD.

CONCLUSIONS

Therefore, this review may provide insight to guide treatment decisions for MDA5⁺ DM-RPILD patients and improve outcomes.

Risk Factors and Predictive Model for Dermatomyositis Associated with Rapidly Progressive Interstitial Lung Disease

Background

Rapidly progressive interstitial lung disease (RP-ILD) is a significant complication that determines the prognosis of dermatomyositis (DM). Early RP-ILD diagnosis can improve screening and diagnostic efficiency and provide meaningful guidance to carry out early and aggressive treatment.

Methods

A retrospective screening of 284 patients with DM was performed. Clinical and laboratory characteristics of the patients were recorded. The risk factors of RP-ILD in DM patients were screened by logistic regression (LR) and machine learning methods, and the prediction models of RP-ILD were developed by machine learning methods, namely least absolute shrinkage and selection operator (LASSO), random forest (RF), and extreme gradient boosting (XGBoost).

Results

According to the result of univariate LR, disease duration is a protective factor for RP-ILD, and ESR, CRP, anti-Ro-52 antibody and anti-MDA5 antibody are risk factors for RP-ILD. The top 10 important variables of the 3 machine learning models were intersected to obtain common important variables, and there were 5 common important variables, namely disease duration, LDH, CRP, anti-Ro-52 antibody and anti-MDA5 antibody. The AUC of LASSO, RF and XGBoost test set were 0.661, 0.667 and 0.867, respectively. We further validated the performance of these three models on validation set, and the results showed that, the AUC of LASSO, RF and XGBoost were 0.764, 0.727 and 0.909, respectively. Based on the results of the models, XGBoost is the optimal model in this study.

Conclusion

Disease duration, LDH, CRP, anti-Ro-52 antibody and anti-MDA5 antibody are vital risk factors for RP-ILD in DM. The prediction model constructed using XGBoost can be used for risk identification and early intervention in DM patients with RP-ILD and practical application.

Biomarkers of disease activity in dermatomyositis

PURPOSE OF REVIEW

This review provides updates regarding biomarker studies that address key clinical unmet needs, which relate to the evaluation of the disease activity in patients with dermatomyositis.

RECENT FINDINGS

Increasing evidence supports that the serum levels of dermatomyositis-specific antibodies (DM-MSAs), which include anti-Mi-2, anti-NXP2, anti-MDA5, anti-TNF1-γ, and anti-SAE, are correlated with the disease activity. Moreover, serial measurements of DM-MSA levels may help to predict the disease status. Beyond the MSA, macrophage activation-related biomarker-soluble CD163, CD206, neopterin, and galectin-3/9 are the most currently talked biomarkers for disease activity in dermatomyositis; new circulating T-cell subsets CD4+CXCR5+CCR7loPD-1hi and TIGIT+CD226+ CD4 T cells can potentially harbor biomarkers of disease activity in dermatomyositis. In addition, LDGs and NETs were also shown to be correlated with the disease activities of dermatomyositis.

SUMMARY

Promising candidate biomarkers are now available for evaluating disease activity in dermatomyositis. These biomarkers need external validation in other large cohort studies.

The importance of neopterin in COVID-19: The prognostic value and relation with the disease severity

Coronavirus Disease 2019 [COVID-19], caused by severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2], has rapidly evolved into a global health emergency. Neopterin [NPT], produced by macrophages when stimulated with interferon [IFN-]gamma, is an essential cytokine in the antiviral immune response. NPT has been used as a marker for the early assessment of disease severity in different diseases. The leading cause of NPT production is the pro-inflammatory cytokine IFN-. Macrophage activation has also been revealed to be linked with disease severity in SARS-CoV-2 patients. We demonstrate the importance of NPT in the pathogenesis of SARS-CoV-2 and suggest that targeting NPT in SARS-CoV-2 infection may be critical in the early prediction of disease progression and provision of timely management of infected individuals.

Supervised Aerobic Exercise Training and Increased Lifestyle Physical Activity to Reduce Cardiovascular Disease Risk for Women With Polycystic Ovary Syndrome: A Randomized Controlled Feasibility Trial

Background: Polycystic ovary syndrome (PCOS) is a complex, heterogeneous endocrinopathy. Women with PCOS often present with cardiovascular disease risk factors. Physical activity (PA) interventions reduce cardiovascular disease risk factors in women with PCOS. However, sedentary behaviors have a distinct deleterious effect on cardiometabolic health. Increasing PA and reducing sedentary behaviors may be a worthwhile therapeutic target to improve cardiovascular health in this population. This study investigated the feasibility of 2 PA interventions to decrease cardiovascular disease risk in women with PCOS. Methods: This was a feasibility randomized controlled trial of 2 PA interventions in 36 women with PCOS. Participants were randomized to a supervised exercise intervention (n = 12), a lifestyle physical activity group intervention aimed at reducing sedentary behaviors (n = 12), or a control group (n = 12), for 12 weeks. Primary outcomes included the feasibility and acceptability of the interventions and procedures. Results: Recruitment rate was 56%. Adherence rate was 53% and 100% to the exercise intervention and lifestyle PA intervention, respectively. Secondary outcome data indicate a reduction in oxidized low-density lipoprotein concentrations in the exercise group, and weight loss in both intervention groups. Conclusions: The procedures for recruitment, allocation, and outcome measurements were acceptable. However, before progression to a full-scale trial, adherence to the exercise program should be addressed.

Oxidative stress, ceruloplasmin and neopterin biomarkers in dromedary camels with clinical endometritis

The purpose of this study is to investigate the role of some oxidative stress (OS), ceruloplasmin (Cp), and neopterin (NPT) as diagnostic biomarkers for dromedary camels endometritis as well as to explore the impact of ceftiofur treatment on endometritis. Camels were categorized into two groups; healthy control group (n = 20) and endometritis group (n = 60). She-camels with clinical signs of endometritis (CE) received 6.6 mg/kg BW of ceftiofur (i/m). On days 7, and 14, she-camels were evaluated and clinical cure or failure to cure was determined. The comparison of the groups for OS demonstrated that endometritis caused an increase in serum malondialdehyde (sMDA), Cp, and NPT levels (P<0.05), but decreased serum levels of superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH) (P<0.05). The most prevalent pathogens involved in the etiology of CE are Arcanobacterium pyogenes, Streptococcus pyogenes, and Staphylococcus aureus. All examined biomarkers demonstrated a high degree of recognition between CE camel and healthy controls (the area under the curve (AUC) was 95.9 for NPT). A higher proportion of camels with CE that were treated with ceftiofur (90%, P<0.0001) showed clinical cure by the first dose, while 10% required a second dose. In conclusion, CE causes increased oxidative reactions and decreased antioxidant defense competence. Subsequently, the alteration in that balance that was represented by the biomarkers of OS could be beneficial for clinical practice and basic clinical research. Additionally, all trials demonstrated the efficacy of ceftiofur for the treatment of CE in she-camel.

Clues to Disease Activity in Juvenile Dermatomyositis: Neopterin and Other Biomarkers

Easily accessible biomarkers are urgently needed to evaluate immune activation in Juvenile Dermatomyositis (JDM). The goal of this retrospective study is to define immunological and clinical differences between untreated JDM patients with either normal or elevated (>10 mmol/L) levels of neopterin, a biomarker of macrophage activation. We included all JDM with neopterin data obtained before initiating medical therapy. We assessed T, B, NK cell populations, muscle enzymes, and disease activity scores for skin (sDAS), muscle (mDAS), total (tDAS), the duration of untreated disease, disease course, and myositis-specific antibody (MSA). Seventy-nine percent of 139 untreated JDM patients had elevated serum neopterin. The group with elevated neopterin had significantly more active disease: tDAS 11.9 vs. 8.1 (p < 0.0001), mDAS 5.8 vs. 3.1 (p < 0.0001), sDAS 6.1 vs. 4.9 (p = 0.0002), aldolase 24.0 vs. 7.6 U/L (p < 0.0001), von Willebrand factor antigen (p < 0.0001), and ESR 19.8 vs. 11.5 mm/hr (p = 0.01). The flow cytometry documented both reduced T cells (1494 vs. 2278/mm3, p = 0.008) and NK cells (145 vs. 240/mm3, p = 0.003). TNFα-308AA/AG polymorphism was more common in children with elevated neopterin than TNFα-308GG (p 0.05). We conclude that the availability of neopterin data will contribute to the rapid assessment of untreated JDM disease activity.

Dermatomyositis With Anti-MDA5 Antibodies: Bioclinical Features, Pathogenesis and Emerging Therapies

Anti-MDA5 dermatomyositis is a rare systemic autoimmune disease, historically described in Japanese patients with clinically amyopathic dermatomyositis and life-threatening rapidly progressive interstitial lung disease. Subsequently, the complete clinical spectrum of the disease was enriched by skin, articular and vascular manifestations. Depending on the predominance of these symptoms, three distinct clinical phenotypes with different prognosis are now defined. To date, the only known molecular component shared by the three entities are specific antibodies targeting MDA5, a cytosolic protein essential for antiviral host immune responses. Several biological tools have emerged to detect these antibodies, with drawbacks and limitations for each of them. However, the identification of this highly specific serological marker of the disease raises the question of its role in the pathogenesis. Although current knowledge on the pathogenic mechanisms that take place in the disease are still in their enfancy, several lines of evidence support a central role of interferon-mediated vasculopathy in the development of skin and lung lesions, as well as a possible pathogenic involvement of anti-MDA5 antibodies. Here, we review the clinical and biological evidences in favor of these hypothesis, and we discuss the contribution of emerging therapies that shed some light on the pathogenesis of the disease.

Biomarkers in Progressive Fibrosing Interstitial Lung Disease: Optimizing Diagnosis, Prognosis, and Treatment Response

Interstitial lung disease (ILD) comprises a heterogenous group of diffuse lung disorders that commonly result in irreversible pulmonary fibrosis. While idiopathic pulmonary fibrosis (IPF) is the prototypical progressive fibrosing ILD (PF-ILD), a high proportion of patients with other ILD subtypes develop a PF-ILD phenotype. Evidence exists for shared pathobiology leading to progressive fibrosis, suggesting that biomarkers of disease activity may prove informative across the wide spectrum of ILDs. Biomarker investigation to date has identified a number of molecular markers that predict relevant ILD endpoints, including disease presence, prognosis, and/or treatment response. In this review, we provide an overview of potentially informative biomarkers in patients with ILD, including those suggestive of a PF-ILD phenotype. We highlight the recent genomic, transcriptomic, and proteomic investigations that identified these biomarkers and discuss the body compartments in which they are found, including the peripheral blood, airway, and lung parenchyma. Finally, we identify critical gaps in knowledge within the field of ILD biomarker research and propose steps to advance the field toward biomarker implementation.

Antiviral proinflammatory phenotype of monocytes in anti-MDA5 antibody-associated interstitial lung disease

OBJECTIVE

To evaluate upstream and downstream regulators leading to macrophage activation and subsequent cytokine storm in patients with anti-melanoma differentiation-associated gene 5 (MDA5) antibody-associated interstitial lung disease (ILD).

METHODS

We conducted an integrated miRNA-mRNA association analysis using circulating monocytes from 3 patients with anti-MDA5-associated ILD and 3 healthy controls and identified disease pathways and a regulator effect network by Ingenuity Pathway Analysis (IPA). The expression of relevant genes and proteins was verified using an independent validation cohort, including 6 patients with anti-MDA5-associated ILD, 5 with anti-aminoacyl tRNA synthetase antibody-associated ILD, and 6 healthy controls.

RESULTS

IPA identified 26 matched pairs of downregulated miRNA and upregulated mRNAs and revealed that canonical pathways mediated by type I IFN signaling and C-C motif ligand 2 (CCL2) were responsible for the pathogenic process (P < 0.05 for all pathways). The regulatory network model identified IFN-β; Toll-like receptors 3, 7, and 9; and PU.1 as upstream regulators, while the downstream effect of this network converged at the inhibition of viral infection. mRNA and protein expression analysis using validation cohort showed a trend towards the increased expression of relevant molecules identified by IPA in patients with anti-MDA5-associated ILD compared with those with anti-aminoacyl tRNA synthetase antibody-associated ILD or healthy controls. The expression of all relevant genes in monocytes and serum levels of CCL2 and IFN-β declined after treatment in survivors with anti-MDA5-associated ILD.

CONCLUSION

An antiviral proinflammatory network orchestrated primarily by activated monocytes/macrophages might be responsible for cytokine storm in anti-MDA5-associated ILD.

Understanding and managing anti-MDA 5 dermatomyositis, including potential COVID-19 mimicry

Anti-Melanoma Differentiation-Associated gene 5 (MDA-5) Dermatomyositis (MDA5, DM) is a recently identified subtype of myositis characteristically associated with Rapidly Progressive Interstitial Lung Disease (RP-ILD) and unique cutaneous features. We reviewed PubMed, SCOPUS and Web of Science databases and selected 87 relevant articles after screening 1485 search results, aiming to gain a better understanding of the pathophysiology, clinical features, diagnosis, and treatment approaches of anti-MDA-5 DM described in the literature. The etiopathogenesis is speculatively linked to an unidentified viral trigger on the background of genetic predisposition culminating in an acquired type I interferonopathy. The clinical phenotype is highly varied in different ethnicities, with new clinical features having been recently described, expanding the spectrum of cases that should raise the suspicion of anti-MDA-5 DM. Unfortunately, the diagnosis is frequently missed despite excessive mortality, calling for wider awareness of suspect symptoms. RP ILD is the major determinant of survival, treatment being largely based on observational studies with recent insights into aggressive combined immunosuppression at the outset.

Neopterin derivatives - a novel therapeutic target rather than biomarker for atherosclerosis and related diseases

This review provides an updated overview of the emerging roles of neopterin derivatives in atherosclerosis. Neopterin, a metabolite of guanosine triphosphate, is produced by interferon-γ-activated macrophages and is expressed at high levels in atheromatous plaques within the human carotid and coronary arteries as well as in the aorta. Plasma concentrations of neopterin are higher in patients with carotid, cerebral, and coronary artery diseases as well as aortic aneurysm. The concentration of neopterin is positively correlated with the severity of coronary artery disease. However, a prospective cohort study showed that neopterin contributes to protection against plaque formation in carotid arteries in patients with atherosclerosis. Moreover, using both in vitro and in vivo experiments, a recent study has shown the atheroprotective effects of neopterin. Neopterin suppresses the expression of monocyte chemotactic protein-1, vascular cell adhesion molecule-1, and intercellular adhesion molecule-1 in endothelial cells, and thereby suppresses the adhesion of monocytes to endothelial cells. It also suppresses the inflammatory phenotype of monocyte-derived macrophages. In addition, neopterin suppresses oxidized low-density lipoprotein-induced foam cell formation in macrophages and the migration and proliferation of vascular smooth muscle cells. Neopterin injection into apolipoprotein E-deficient (Apoe^-/-) mice suppresses the development of atherosclerotic lesions. A neopterin derivative tetrahydroneopterin (BH4), also known as a cofactor for nitric oxide (NO) synthases, suppresses atherosclerosis and vascular injury-induced neointimal hyperplasia in Apoe^-/- mice. BH4 administration improves endothelial dysfunction in patients with coronary artery disease. These findings suggest that neopterin production may increase to counteract the progression of atherosclerosis, as neopterin contributes to atheroprotection. Otherwise, the increased neopterin levels in atherosclerosis may reflect a compensatory mechanism associated with inducible NO synthase upregulation in macrophages to supply BH4 for high output NO production caused by decreased endothelial NO synthase in atherosclerosis. Therefore, neopterin derivatives are a novel therapeutic target for atherosclerosis and related diseases.