Lowered IgM natural autoantibody concentrations correlate with severity of juvenile idiopathic arthritis

Overview

This study found that lower serum levels of IgM natural autoantibodies against heat shock proteins (Hsp60 and Hsp70) are associated with more severe phenotypes of juvenile idiopathic arthritis (JIA) during remission. No significant differences were observed in IgG levels between patients and healthy controls.

Background

Juvenile idiopathic arthritis (JIA) is the most common chronic inflammatory rheumatic disease in children, characterized by joint inflammation of unknown origin. The severity of JIA can vary significantly.

Data Highlights

No significant differences in anti-Hsp60 or anti-Hsp70 nAAb levels were observed between patients with JIA and healthy controls. However, patients with polyarticular JIA exhibited significantly lower IgM levels compared to those with milder oligoarticular forms.

Key Findings

• Lower levels of IgM autoantibodies against Hsp60 and Hsp70 correlate with more severe JIA phenotypes.
• No significant differences in IgG levels were found between JIA patients and healthy controls.
• Patients were stratified by treatment regimen, but no significant differences in nAAb levels were observed between treatment groups.
• The study involved 47 children with JIA in remission and 22 healthy controls.
• Natural autoantibodies may play a role in immune homeostasis in JIA.

Clinical Implications

The findings indicate that measuring IgM natural autoantibody levels could provide insights into the severity of JIA in children.

Conclusion

Reduced IgM natural autoantibody levels against heat shock proteins are associated with more severe JIA.

Related Resources & Content

1. American College of Rheumatology, ACR Releases Updated Juvenile Idiopathic Arthritis Guidelines, 2026 -- ACR Releases Updated Juvenile Idiopathic Arthritis Guidelines
2. Clinical Rheumatology, Association of Anti-Mitochondrial Autoantibodies with Cardiomyopathy, Dysphagia, and Severe Disease Manifestations in Adult-Onset Myositis, 2021 -- Association of Anti-Mitochondrial Autoantibodies with Cardiomyopathy, Dysphagia, and Severe Disease Manifestations in Adult-Onset Myositis
3. Clinical Rheumatology, Novel Biomarker Potential: Anti-α-1,4-D-polygalacturonic Acid Antibodies in Juvenile Idiopathic Arthritis, 2024 -- Novel Biomarker Potential: Anti-α-1,4-D-polygalacturonic Acid Antibodies in Juvenile Idiopathic Arthritis
4. Clinical Rheumatology, Oxidative Stress and Serum Antioxidant Levels in Juvenile Idiopathic Arthritis, 2014 -- Oxidative Stress and Serum Antioxidant Levels in Juvenile Idiopathic Arthritis
5. Clinical Rheumatology — A Comprehensive Review of Potential Pharmacological Interventions for Nephritis in Pediatric Patients with IgA Vasculitis (HSP)
6. ACR Releases Updated Juvenile Idiopathic Arthritis Guidelines | American College of Rheumatology
7. Review
8. Peng et al. Pediatric Rheumatology (2025) 23:71