Protective alpha1-Antitrypsin Effects in Autoimmune Vasculitis Are Compromised by Methionine Oxidation

Plasma and blood neutrophils were assessed for PR3 and AAT. Wild-type, mutant, and oxidation-resistant AAT species were produced to characterize AAT-PR3 interactions by flow cytometry, immunoblotting, FRET assays, and surface plasmon resonance measurements.