Fig. 1.

MPO selectively produces HOCl and EPO selectively produces HOBr. MPO found in neutrophils, monocytes, and macrophages utilize Cl⁻ ions and H₂O₂ to produce HOCl following a respiratory burst and degranulation. However, some Br^- ions are used by MPO to produce HOBr (not depicted). EPO, found in eosinophils, selectively utilizes Br^- ions and H₂O₂ to produce HOBr even though Br^- ion concentrations are 1,000 times lower than the Cl⁻ concentrations physiologically. Both HOCl and HOBr can attack the vinyl either bond of plasmalogen to release lysosphospholipid and α-ClFALD or α-BrFALD, respectively.