Anti-TRIM72 Autoantibodies in Idiopathic Inflammatory Myopathies

Area of Science:

• Immunology
• Rheumatology
• Molecular Biology

Background:

• Tripartite motif-containing protein 72 (TRIM72) plays a role in tissue repair.
• Autoantibodies against TRIM72 (anti-TRIM72) are found in patients with idiopathic inflammatory myopathies (IIM).
• These autoantibodies may disrupt TRIM72 function, potentially impacting disease severity.

Purpose of the Study:

• To investigate the association between anti-TRIM72 autoantibodies and clinical phenotypes in IIM.
• To determine if IIM patients with anti-TRIM72 antibodies exhibit a more severe disease presentation.

Main Methods:

• Sera from IIM patients (antisynthetase syndrome [ASyS], immune-mediated necrotizing myopathy [IMNM], dermatomyositis [DM]) and healthy controls (HC) were analyzed.
• Enzyme-linked immunosorbent assay (ELISA) was used to detect anti-TRIM72 autoantibodies.
• Clinicodemographic features were compared between anti-TRIM72 positive and negative patient groups.

Main Results:

• Anti-TRIM72 levels were significantly higher in ASyS and IMNM patients compared to DM and HC.
• Elevated anti-TRIM72 levels were observed in patients with specific autoantibodies including anti-Jo-1, anti-PL7, anti-HMGCR, anti-SRP, and anti-MDA5.
• In ASyS, anti-TRIM72 positivity was associated with normal DLCO, not a more severe phenotype.
• In anti-HMGCR(+) IMNM, anti-TRIM72 positivity correlated with older age and a lower proportion of females, but not other clinical features.

Conclusions:

• Anti-TRIM72 antibody titers are increased in ASyS and IMNM patients.
• The presence of anti-TRIM72 antibodies was not linked to a more severe clinical phenotype in ASyS or anti-HMGCR(+) IMNM.
• A higher proportion of ASyS patients with normal DLCO were anti-TRIM72 positive.