CD63 and granulomatosis with polyangiitis: No differences between the study groups were found in expression of EVs marker CD63 (Fig. 1D and E), active GPA: 134.4 ± 20.1 MFI; remission of GPA: 124.5 ± 15.3 MFI; healthy control 136.8 ± 22.1 MFI.