Sulfite-mediated oxidation of myeloperoxidase to a free radical: Immuno-spin trapping detection in human neutrophils

► Reactive (bi)sulfite radicals can damage target proteins and oxidize them to protein radicals. ► Myeloperoxidase (MPO) may initiate respiratory damage caused by (bi)sulfite (sulfur dioxide). ► (Bi)sulfite can cause MPO-catalyzed oxidation of itself to a protein radical in activated neutrophils.