Pathogenic role and clinical relevance of antineutrophil cytoplasmic antibodies in vasculitides.

Within the last year, a growing body of evidence for a distinct role of antineutrophil cytoplasmic antibodies (ANCA) in the pathogenesis of ANCA-associated vasculitides (AAV) has developed. An experimental model of myeloperoxidase (MPO)-ANCA-associated vasculitis provided direct and convincing in vivo evidence that MPO-ANCA are primary pathogenic factors in small-vessel vasculitis by augmenting of leukocyte-vessel wall interaction and leukocyte-mediated vascular injury. Determination of bacterial lipopolysaccharide (LPS) effects on disease severity in a mouse model of anti-MPO-induced glomerulonephritis showed that ANCA and other proinflammatory stimuli of infectious origin acted in synergism in the development of destructive inflammation.