Novel biomarkers for prediction of outcome and therapeutic response in juvenile idiopathic arthritis

Effects of a home-based exercise combined yoga and resistance training in enthesitis-related arthritis in China: study protocol for a randomised controlled trial

INTRODUCTION

Enthesitis-related arthritis (ERA) is a category of juvenile idiopathic arthritis (JIA). The complications of JIA include pain, muscle weakness, limited movement and worsening quality of life. Yoga is an effective exercise therapy for rheumatoid arthritis and may have similar benefits for JIA. Considering the limitation of yoga for strengthening muscles, combined yoga and resistance training (CYRT) may compensate for the shortcomings and provide more benefits for JIA patients. Despite this, there is currently a lack of studies investigating the effectiveness of CYRT for JIA patients. Due to the inaccessibility of traditional exercise therapy, home-based exercise is needed. The study aims to assess the effectiveness of home-based CYRT on JIA.

METHODS AND ANALYSIS

This is a 12-week randomised single-blind controlled trial study. 60 patients with ERA will be randomised into two groups: the home-based exercise group (HBE) and the health education (HE) group. The HBE group (n=30) will perform the CYRT programme 3 times a week at home for 12 weeks and receive HE. The HE group (n=30) will only receive HE. The outcomes include primary outcome (pain levels) and secondary outcomes (lower limb muscle strength, motion range of joint, aerobic fitness, function ability, fatigue levels, mental health, quality of life and blood biomarkers). The assessments will be conducted at baseline, postintervention (12 weeks) and follow-up (24 weeks). Data will be analysed by intention to treat.

ETHICS AND DISSEMINATION

This study has been approved by the Ethics Committee of Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine in December 2023 (approval no. XHEC-C-2023-059-3). This study will require informed consent from all subjects and guardians of children under 18 years of age. The findings will be published in a peer-reviewed journal and international conferences.

TRIAL REGISTRATION NUMBER

ChiCTR2300073446.

Treat-to-Target in Pediatric Rheumatic Diseases

PURPOSE OF REVIEW

To summarize the current evidence on the adoption of the treat-to-target (T2T) strategy in pediatric rheumatic diseases (PRD).

RECENT FINDINGS

The recent advances in the management of PRD have markedly increased the ability to achieve disease remission. Complete disease quiescence is regarded as the ideal therapeutic goal because its attainment leads to lesser long-term damage and physical disability, and to optimization of quality of life. Studies in adult rheumatic diseases have shown that patient outcomes are improved if complete suppression of the inflammatory process is aimed for by frequent adjustments of therapy according to quantitative indices. This approach, which underlies the T2T concept, has been applied in strategic trials in rheumatoid arthritis (RA). Furthermore, recommendations for the T2T have been issued for RA and other adult rheumatic diseases. There is currently a growing interest for the introduction of T2T in PRD, and recommendations for treating juvenile idiopathic arthritis (JIA) to target were promulgated. A similar initiative has been undertaken for childhood-onset systemic lupus erythematosus. Preliminary therapeutic studies have explored the T2T design in JIA. The T2T strategy is a modern therapeutic approach that holds the promise of improving the outcomes in patients with PRD.

The clinical and experimental treatment of Juvenile Idiopathic Arthritis

Juvenile idiopathic arthritis (JIA) is the most common chronic rheumatic disease in children and comprises of multiple subtypes. The most relevant disease subtypes, grouped upon current insight in disease mechanisms, are nonsystemic (oligo- and polyarticular) JIA and systemic JIA (sJIA). In this review, we summarize some of the main proposed mechanisms of disease in both nonsystemic and sJIA and discuss how current therapeutic modalities target some of the pathogenic immune pathways. Chronic inflammation in nonsystemic JIA is the result of a complex interplay between effector and regulatory immune cell subsets, with adaptive immune cells, specifically T-cell subsets and antigen-presenting cells, in a central role. There is, however, also innate immune cell contribution. SJIA is nowadays recognized as an acquired chronic inflammatory disorder with striking autoinflammatory features in the first phase of the disease. Some sJIA patients develop a refractory disease course, with indications for involvement of adaptive immune pathways as well. Currently, therapeutic strategies are directed at suppressing effector mechanisms in both non-systemic and sJIA. These strategies are often not yet optimally tuned nor timed to the known active mechanisms of disease in individual patients in both non-systemic and sJIA. We discuss current treatment strategies in JIA, specifically the 'Step-up' and 'Treat to Target approach' and explore how increased insight into the biology of disease may translate into future more targeted strategies for this chronic inflammatory disease at relevant time points: preclinical disease, active disease, and clinically inactive disease.

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.

MicroRNAs in Juvenile Idiopathic Arthritis: State of the Art and Future Perspectives

Juvenile Idiopathic Arthritis (JIA) represents the most common chronic pediatric arthritis in Western countries and a leading cause of disability in children. Despite recent clinical achievements, patient management is still hindered by a lack of diagnostic/prognostic biomarkers and targeted treatment protocols. MicroRNAs (miRNAs) are short non-coding RNAs playing a key role in gene regulation, and their involvement in many pathologies has been widely reported in the literature. In recent decades, miRNA's contribution to the regulation of the immune system and the pathogenesis of autoimmune diseases has been demonstrated. Furthermore, miRNAs isolated from patients' biological samples are currently under investigation for their potential as novel biomarkers. This review aims to provide an overview of the state of the art on miRNA investigation in JIA. The literature addressing the expression of miRNAs in different types of biological samples isolated from JIA patients was reviewed, focusing in particular on their potential application as diagnostic/prognostic biomarkers. The role of miRNAs in the regulation of immune responses in affected joints will also be discussed along with their potential utility as markers of patients' responses to therapeutic approaches. This information will be of value to investigators in the field of pediatric rheumatology, encouraging further research to increase our knowledge of miRNAs' potential for future clinical applications in JIA.

Serum levels of soluble urokinase plasminogen activator receptor in juvenile idiopathic arthritis: a single-center Swedish case-control study

OBJECTIVES

Reliable biomarkers in the early stages of idiopathic arthritis (JIA) are scarce and the disease heterogeneity makes it clinically challenging to predict the risk of joint damage. Biomarkers with prognostic potential are warranted in order to individualize treatment and follow-up in JIA. The soluble urokinase plasminogen activator receptor (suPAR) has been reported as an easily measurable biomarker for prognosis and severity in several rheumatic diseases but it has never been studied in JIA.

METHODS

Sera from 51 well-characterized patients with JIA and 50 age- and sex-matched control subjects were collected and stored for later analysis of suPAR. Patients were carefully followed clinically over 3 years and analysis of erythrocyte sedimentation rate, C-reactive protein, rheumatoid factor (RF) and antibodies against cyclic citrullinated peptides (anti-CCP) were analyzed as part of clinical routine. Signs of joint erosions were evaluated by radiography.

RESULTS

Overall, the levels of suPAR did not differ significantly between JIA patients and controls but those with polyarticular involvement showed higher suPAR (p = 0.013). In addition, elevated suPAR were associated with joint erosions (p = 0.026). Two RF/anti-CCP negative individuals with erosions showed high levels of suPAR.

CONCLUSIONS

We present new data on the biomarker suPAR in JIA. Our results indicate that, apart from RF and anti-CCP, analysis of suPAR could be of additional value in assessing the risk of erosions. Analysis of suPAR early could potentially guide treatment decision-making in JIA, but our observations should be confirmed in prospective studies.

Proteomic profiling of extracellular vesicles in synovial fluid and plasma from Oligoarticular Juvenile Idiopathic Arthritis patients reveals novel immunopathogenic biomarkers

Introduction

New early low-invasive biomarkers are demanded for the management of Oligoarticular Juvenile Idiopathic Arthritis (OJIA), the most common chronic pediatric rheumatic disease in Western countries and a leading cause of disability. A deeper understanding of the molecular basis of OJIA pathophysiology is essential for identifying new biomarkers for earlier disease diagnosis and patient stratification and to guide targeted therapeutic intervention. Proteomic profiling of extracellular vesicles (EVs) released in biological fluids has recently emerged as a minimally invasive approach to elucidate adult arthritis pathogenic mechanisms and identify new biomarkers. However, EV-prot expression and potential as biomarkers in OJIA have not been explored. This study represents the first detailed longitudinal characterization of the EV-proteome in OJIA patients.

Methods

Fourty-five OJIA patients were recruited at disease onset and followed up for 24 months, and protein expression profiling was carried out by liquid chromatography-tandem mass spectrometry in EVs isolated from plasma (PL) and synovial fluid (SF) samples.

Results

We first compared the EV-proteome of SF vs paired PL and identified a panel of EV-prots whose expression was significantly deregulated in SF. Interaction network and GO enrichment analyses performed on deregulated EV-prots through STRING database and ShinyGO webserver revealed enrichment in processes related to cartilage/bone metabolism and inflammation, suggesting their role in OJIA pathogenesis and potential value as early molecular indicators of OJIA development. Comparative analysis of the EV-proteome in PL and SF from OJIA patients vs PL from age/gender-matched control children was then carried out. We detected altered expression of a panel of EV-prots able to differentiate new-onset OJIA patients from control children, potentially representing a disease-associated signature measurable at both the systemic and local levels with diagnostic potential. Deregulated EV-prots were significantly associated with biological processes related to innate immunity, antigen processing and presentation, and cytoskeleton organization. Finally, we ran WGCNA on the SF- and PL-derived EV-prot datasets and identified a few EV-prot modules associated with different clinical parameters stratifying OJIA patients in distinct subgroups.

Discussion

These data provide novel mechanistic insights into OJIA pathophysiology and an important contribution in the search of new candidate molecular biomarkers for the disease.

Emerging therapies for juvenile arthritis: agents in early clinical trials

INTRODUCTION

Juvenile idiopathic arthritis (JIA) is the most common chronic inflammatory rheumatic condition in childhood. The management of JIA has been revolutionized thanks to the development of new powerful drugs and the possibility to conduct controlled clinical trials with support from legislative initiatives and availability of international collaborative networks. Trials are still needed in children because we now have new drugs related to specific JIA category.

AREAS COVERED

The review is centered on the latest achievements in the field, focusing on new investigational drugs which are currently or have been recently tested for JIA treatment, encompassing agents in early phase of clinical development.

EXPERT OPINION

Despite the tremendous improvement witnessed in the field of JIA treatment in the past 20 years, there are still many unmet needs to be prioritized. Studies on disease pathogenesis will hopefully help in the identification of new treatment targets for individual JIA categories, that could possibly favor a stricter disease control and contribute to solve the issue of refractory JIA. Novel strategies aimed at the prevention of the risk of long-term joint damage are also desirable, as well as the discovery of predictive biomarkers for treatment efficacy and safety in the individual patient.

Serum Calprotectin a Potential Biomarker in Juvenile Idiopathic Arthritis: A Meta-Analysis

Juvenile idiopathic arthritis (JIA) is the most common inflammatory chronic disease affecting children and adolescents. Today, there are no specific biomarkers of inflammation. Therefore, it is important to identify new markers as predictors of disease activity. Recently, some researchers have directed their interest toward a protein, calprotectin (CLP), as a potential biomarker. The primary objective of our systematic review and meta-analysis was to analyze the possible role of CLP in JIA. Method: A literature search was conducted using PubMed, EMBASE, Scopus, Science Direct on 10 August 2021. The selection of studies was made using the PRISMA 2020 guidelines. Cohen’s d with 95% CI and p-value were used as a measure of effect size. The random effects model was used to account for different sources of variation among studies. Heterogeneity was assessed using Q statistics and I². The publication bias was analyzed and represented by a funnel plot, and funnel plot symmetry was assessed with Egger’s test. Results: Our results at follow-up showed a statistically significant difference between patients with active disease compared to patients with inactive disease: 0.39 (0.16; 0.62), p = 0.001; without statistical heterogeneity. Another important aspect that emerged were the differences between the systemic disease form and any form of inactive disease showing a different concentration of calprotectin: 0.74 (0.40; 1.08), p < 0.001; without statistical heterogeneity. On the other hand, meta-regression analyses performed on gender, age, duration of disease, percentage of patients with ANA+ or RF+, medium value of ESR or CRP were not statistically significant. A statistically significant difference in serum calprotectin concentration between patients with JIA and healthy controls were observed. In fact, it presented lower values in the control group. Conclusions: The use of serum CLP could represent, in the future, a useful tool in JIA in order to stratify disease activity more accurately and may aid a more tailored approach to drug of choice in children with JIA. Further studies are needed to evaluate CLP as a predictor of flare in combination with other potential biomarkers of subclinical disease activity.