Newer insights into the aetiology and pathogenesis of myeloperoxidase associated autoimmunity

In recent years there have been substantial developments in the understanding of the aetiology and pathogenesis of ANCA-associated vasculitides, including myeloperoxidase (MPO) associated autoimmunity. This review will describe genetic and environmental factors that may increase the risk for the disease and will summarise findings demonstrating that T-cells, B-cells and ANCA themselves are of pathogenetic significance. Leukocyte gene expression profiles indicate that the reactivation of granule protein genes contributes to the pathogenesis of AASV. Finally, data derived from closely related autoantibodies against proteinase 3 (PR3) suggest anti-idiotypic antibodies induced by antisense transcripts as potential pathological agents.