INDUCTION OF ENDOTHELIAL-CELL ADHESION MOLECULES BY SERUM AND IMMUNOGLOBULINS-G FROM A PATIENT WITH VASCULITIS AND MONOCLONAL GAMMOPATHY - POTENTIAL RELEVANCE TO VASCULITIS

Interactions between endothelial cell adhesion molecules and their bet a(2) integrin adhesive receptors on leukocytes are thought to Flay a r ole in the pathogenesis of inflammatory diseases and probably vasculit is. We describe a case in whom leukocytoclastic vasculitis was associa ted to a monoclonal immunoglobulin G(2) kappa (IgG(2)K). During the va sculitic crisis, the patients serum and the isolated IgG from this ser um induced the expression of E-selectin, VCAM-1 and ICAM-1 at the HUVE C surface, but not tissue factor activity, whereas normal, control ser um and patient serum at remission were without any effect. A close rel ationship between the vasculitis and the serum level of the monoclonal IgG was observed. We suggest that the monoclonal IgG might induce the vasculitis by increasing the expression of E-selectin, VCAM-1 and ICA M-1 which facilitate the interaction of leukocytes with vascular endot helium.