PRTN3 and granulomatosis with polyangiitis: We found no significant difference in the degree of maturation of PMNs from GPA patients (n = 8) and healthy controls (n = 11) as determined from cell surface expression of the neutrophil maturation marker CD16 and gene expression profile of FCGR3B. The expression of PRTN3 and KDM6B mRNAs and miR-941 was not significantly different in GPA patients and healthy controls.