In experimental murine myeloperoxidase (MPO)-ANCA-associated vasculitis (AAV), MC-derived IL-10 enhanced the immunosuppressive function of Treg and played a protective role in MPO-related inflammation (Gan et al., 2012; Gan et al., 2016). This evidence concerns the gene MPO and anti-neutrophil cytoplasmic antibody-associated vasculitis.