Cellular immune regulation in the pathogenesis of ANCA-associated vasculitides

Anti-neutrophil cytoplasmic autoantibody (ANCA)-associated vasculitides (AAV) are systemic autoimmune diseases characterized by necrotizing inflammation of small- to medium-sized blood vessels, affecting primarily the lungs and kidneys. Both animal and human studies show that the balance between inflammatory- and regulatory T and B cells determines the AAV disease pathogenesis. Recent evidence shows malfunctioning of the regulatory lymphocyte compartment in AAV. In this review we summarize the immune regulatory properties of both T- and B cells in patients with AAV and discuss how aberrations herein might contribute to the disease pathogenesis.