[PDF][PDF] Human eosinophil peroxidase: a novel isolation procedure, spectral properties and chlorinating activity

R Wever, H Plat, MN Hamers - FEBS letters, 1981 - core.ac.uk
R Wever, H Plat, MN Hamers
FEBS letters, 1981core.ac.uk
Like neutrophils, eosinophils contain a high concentration of a peroxidase that may have
enzymic activity which is associated with the antiparasitic function of these cells [11. In
neutrophils it has been demonstrated that the peroxidase (myeloperoxidase) is involved in
the killing of micro-organisms (reviewed in [2]). This antimicrobial activity of
myeloperoxidase is probably due to the ability of this enzyme to oxidize Cl-with HzOz to the
reactive hypochlorous acid (HOCl)[3-51. It is not known whether human eosinophil …
Like neutrophils, eosinophils contain a high concentration of a peroxidase that may have enzymic activity which is associated with the antiparasitic function of these cells [11. In neutrophils it has been demonstrated that the peroxidase (myeloperoxidase) is involved in the killing of micro-organisms (reviewed in [2]). This antimicrobial activity of myeloperoxidase is probably due to the ability of this enzyme to oxidize Cl-with HzOz to the reactive hypochlorous acid (HOCl)[3-51. It is not known whether human eosinophil peroxidase can catalyse the same reaction. It was recently shown [6], however, that eosinophil peroxidase partially purified from guinea pig eosinophils is bactericidal when combined with Hz02 and Cl-. Studies on human eosinophil peroxidase are hampered since eosinophils can only be obtained in significant amounts from blood from patients with eosinophilia. However, in order to be able to purify the peroxidase from these eosinophils and to study the enzyme in some more detail, sufficient patient blood must be available, which is generally not the case. In addition, it is conceivable that the properties of patient eosinophils, and the enzymes in these cells, differ from those normally foundin blood circulation. As shown in [7] the amount of haem iron derived from the peroxidase in an eosinophil is-4-times higher than the concentration of myeloperoxidase in a neutrophil. Since white blood cells of normal donors contain 3-S% eosinophils, 12-20% of the total peroxidase (on the basis of haem iron) in a homogenate of white cells must be due to eosinophil peroxidase. From 100 1 human blood 200 mg pure myeloperoxidase can be obtained [8]; it should therefore be pos-
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