Immunohistochemical analysis of adhesion molecule expression on muscle biopsy specimens from patients with juvenile dermatomyositis

Objective. To assess expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) on muscle biopsy specimens from patients with untreated juvenile dermatomyositis (JDM).Methods. Histochemical and immunohistochemical tests for ICAM-1 and VCAM-1 were performed on serial frozen sections from 27 JDM muscle biopsy specimens. ICAM-1 and VCAM-1 expression was analyzed on capillaries, perimysial and endomysial large vessels, and muscle fibers. Expression was assessed and graded semiquantitatively.Results. Increased ICAM-1 expression was observed on capillaries and perimysial large vessels on semiquantitative analysis, and was statistically more evident than on endomysial large vessels. In all cases, only a few muscle vessels showed expression of VCAM-1. Expression of ICAM-1 and VCAM-1 was observed on few muscle fibers.Conclusion. The observation of ICAM-1 expression on muscle vessels, mainly on capillaries of patients with untreated JDM compared to controls, and. VCAM-1 expression to a lesser extent, mostly on muscle vessels surrounded by inflammatory infiltrate, supports the participation of these adhesion molecules in the pathologic mechanism of vascular injury in JDM.Univ Sao Paulo, Sch Med, Dept Pediat, Sao Paulo, BrazilUniv Sao Paulo, Sch Med, Dept Neurol, Sao Paulo, BrazilUniv Sao Paulo, Sch Med, Dept Rheumatol, Sao Paulo, BrazilSanat Casa Misericordia Sao Paulo Med Sch, Dept Pediat, Sao Paulo, BrazilAdolfo Lutz Inst, Sao Paulo, BrazilWeb of Scienc