Project description:Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a systemic and refractory disease, characterized by necrotizing small to medium vessel vasculitides. AAV constitutes three distinct disorders: microscopic polyangiitis (MPA), granulomatosis with polyangiitis (GPA) (formerly known as Wegener's granulomatosis), and eosinophilic granulomatosis with polyangiitis (EGPA) (formerly known as Churg-Strauss syndrome). ANCA, a characteristic autoantibody for AAV consists of two major subtypes: one against myeloperoxidase (MPO-ANCA) and the other against leukocyte proteinase 3 (PR3-ANCA). MPO-ANCA is mainly detected in patients with MPA (55-90%) and in those with EGPA (20-40%) and less frequently detected in patients with GPA (20-30%). We hypothesized that an aberrant PTM occurred in neutrophil MPO in patients with MPO-ANCA-positive AAV (MPO-AAV) is involved in the production of MPO-ANCA. To test the hypothesis, SWATH-MS was used to comprehensively quantify PTMs of human MPO purified from neutrophils of MPO-AAV and healthy controls, and PTMs of mouse MPO treated with hydrogen peroxide in vitro.
Project description:Regulatory T cells (Tregs) are frequently functionally impaired in patients with Granulomatosis with PolyAngiitis (GPA). However, the mechanism underlying their impaired function is unknown. Here, we hypothesized that Treg dysfunction in GPA is due to altered microRNA (miRNA) expression.