Antibodies to proteinase 3 mediate expression of vascular cell adhesion molecule-1 (VCAM-1)

Abstract

VCAM‐1 was first identified as an adhesion molecule induced on human endothelial cells (HEC) by inflammatory cytokines such as IL‐1, tumour necrosis factor (TNF), and lipopolysaccharide (LPS). The molecule binds to a variety of leucocytes, including B cells, T cells, basophils, eosinophils and monocytes. Vascular expression of VCAM‐1 has been associated with a number of disease states, including rheumatoid arthritis and vasculitis. The detection of antineutrophil cytoplasmic antibodies (ANCA), especially to proteinase 3 (PR3), has become important in the diagnosis of Wegener’s granulomatosis (WG) and related vasculitides. Recently we were able to demonstrate a direct effect of anti‐PR3 antibodies on neutrophil–endothelial interactions (Blood 1993; 82:1221). Binding of anti‐PR3 antibodies to their antigen translocated into the membrane of HEC leads to an enhanced adhesion of neutrophils via induction of E‐selectin (Clin Exp Immunol 1993; 94:440). The aim of this study was to investigate the effect of anti‐PR3 antibodies on the expression of VCAM‐1. HEC was isolated from umbilical vein and cultured on microtitre plates. After preincubatiion with purified anti‐PR3 antibody, purified control antibodies (SS‐A, SS‐B, RNP) (IgG and F(ab′)2 fragments) or different cytokines (controls), VCAM‐1 was detected on the surface of unfixed HEC by cyto‐ELISA and polymerase chain reaction analysis. Incubation of HEC with anti‐PR3 antibodies led to a marked increase of endothelial VCAM‐1 expression with a peak after 8 h. Incubation with TNF‐α also led to maximal VCAM‐1 expression after 4–6 h (control). Increased adhesion of T lymphocytes to HEC after binding of anti‐PR3 antibodies to their antigen could be confirmed by performing adherence assays. This effect could be inhibited by antibodies to VLA‐4. In conclusion, we have been able to show that cytokine‐like effects of anti‐PR3 antibodies on HEC are not limited to induction of neutrophil adhesion. Anti‐PR3 antibodies may thus contribute to the regulation of T lymphocyte migration from the blood by HEC in ANCA‐related vasculitides.

Subacute bacterial endocarditis with positive cytoplasmic antineutrophil cytoplasmic antibodies and anti-proteinase 3 antibodies

“…In systemic vasculitis, there has been evidence suggesting ANCA plays an important role in pathogenesis. Anti-PR3 antibodies have been shown to enhance the activation and adhesion of neutrophils (17,18).…”

Cell adhesion molecules in the development of inflammatory infiltrates in giant cell arteritis: Inflammation-induced angiogenesis as the preferential site of leukocyte-endothelial cell interactions

“…Activated complement products, antineutrophil cytoplasmic antibody binding to their cognate enzymes expressed at the surface of neutrophils or endothelial cells, and proinflammatory cytokines released upon T lymphocyte and macrophage activation have been demonstrated to up-regulate endothelial adhesion molecule expression or to increase leukocyte integrin function (17)(18)(19). Previous studies have shown that, at some point, endothelial adhesion molecules for leukocytes are expressed in inflamed vessels from patients with vasculitis, suggesting their participation in the development of vascular inflammation by mediating leukocyte recruitment in the vessel wall (17,(20)(21)(22).…”

Interaction of Antibodies to Proteinase 3 (Classic Anti-Neutrophil Cytoplasmic Antibody) with Human Renal Tubular Epithelial Cells: Impact on Signaling Events and Inflammatory Mediator Generation

“…Moreover, the presence of PR3-specific mRNA was detected in cultured cytokine-treated human endothelial and renal TECs (26,27), as well as in kidney biopsies, with distal tubules as well as glomerular epithelia being strongly positive for PR3 message (28). While binding of c-ANCA to endothelial cells is followed by expression of adhesion molecules (29) and activation of signaling responses such as phosphoinositide hydrolysis with progressive loss of endothelial barrier properties (30), the effects of c-ANCA interaction with renal TECs are largely unknown. Such interaction may, however, be of major interest, as renal TEC may well be involved in inflammatory events, by expression of adhesion molecules, promotion of leukocyte recruitment, and synthesis of inflammatory mediators (6 -10).…”