Expression of cell adhesion molecules in inflammatory myopathies: immunohistochemical study of 17 cases

We investigated the immunohistochemical expression of endothelial cell adhe sion molecules in 17 cases of idiopathic inflammatory myopathies. The prese nt study revealed: I) a constitutive expression of ICAM-1, ICAM-2 and PECAM -1, but nor VCAM-1, LFA-3 and E-selectin, on endothelial cells in normal mu scles; 2) a modification of cell adhesion molecules expression in idiopathi c inflammatory myopathies with an increased expression of the expressed mol ecules constitutively I an expression of LFA-3 and VCAM-1 on capillary endo thelial cells in polymyositis/inclusion body myositis, these molecules bein g only observed on endothelial cells of some arterioles in dermatomyositis; 3) an expression of all these molecules on. inflammatory cells in inflamma tory myopathies. In dermatomyositis, the expression of ICAM-1 and VCAM-1, p redominated on mononuclear cells located near vessels. In polymyositis/ inc lusion body myositis, a strong expression of ICAM-1, VCAM-1 and LFA-3 was p resent on inflammatory cells invading non necrotic muscle fibers; 4) absenc e of E-selectin on endothelial and inflammatory cells in all cases.