The steps leading to key pathogenetic aspect of ANCA-associated vasculitis, such as lung nodules in granulomatosis with polyangiitis (GPA), onset of glomerulonephritis (GN) in experimental myeloperoxidase (MPO)-ANCA models and the implications of carrying staphylococcal superantigens, such as toxic shock syndrome toxin-1 (tsst-1), in GPA remain to be elucidated. The session 'Cellular and molecular mechanisms of disease (II)' was devoted to close some of these knowledge gaps and underlined that research in ANCA-associated vasculitis leads to more granular understanding of these complex diseases. Here, we present an overview of this session at a glance.