Detection of anti-p155/140, anti-p140, and antiendothelial cells autoantibodies in patients with juvenile dermatomyositis.

Abstract

The pathogenesis of juvenile dermatomyositis (JDM), the most common idiopathic inflammatory myopathy in children, is unclear. The identification of novel autoantibodies in JDM may have clinical implications. The aim of this study was to assess the presence of anti-p155/140, anti-p140 antibodies, and antiendothelial cells antibodies (AECA) in patients with JDM and to correlate autoantibodies with clinical manifestations. Serum AECA against human umbilical vein endothelial cells were detected by enzyme-linked immunosorbent assay in 25 patients with JDM and 17 normal controls. Immunoblotting was performed to detect serum anti-p155/140 and anti-p140 antibodies. Patients with JDM had significantly higher serum levels of AECA than healthy controls (p = 0.002). Nineteen patients (76%) and five control patients (29.4%) had positive AECAs (p = 0.003). The cutoff point of serum levels of AECA was determined by the receiver operating characteristic (ROC) curve analysis. Anti-p155/140 and anti-p140 antibodies were detected in 9 patients and 7 patients with JDM (36% and 28%, respectively). Anti-p155/140 antibodies were significantly associated with higher proportion of ESR elevation (100% vs. 0%, p = 0.006), higher erythrocyte sedimentation rate levels at diagnosis (40.3 ± 15.5 vs. 13.4 ± 5.3, p = 0.019), and a younger age at diagnosis (5.2 ± 3.2 years vs. 8.0 ± 3.0 years, p = 0.03). anti-p155/140, anti-p140, and AECA antibodies are significantly associated with JDM. The roles of autoantibodies in the pathogenesis await further investigation.