Journal of Dental Research, Vol 69, 1780-1783, Copyright © 1990 by International & American Associations for Dental Research Online Journals
Preferential adsorption of human neutrophil myeloperoxidase isoform III by oral bacteria
K. T. Miyasaki
Section of Oral Biology, UCLA School of Dentistry 90024-1668.
Neutrophil myeloperoxidase (MPO) adsorbs to bacteria as a pre-requisite for
killing by the MPO/hydrogen-peroxide/chloride system. Three
chromatographically distinct isoforms of MPO (MPO I, MPO II, and MPO III)
have been isolated from human neutrophils. The purpose of this study was to
determine whether oral bacteria--including Actinobacillus
actinomycetemcomitans, Capnocytophaga sputigena, Haemophilus aphrophilus,
and Eikenella corrodens--differentially adsorb the three major isoforms of
MPO from a mixture of MPO I, II, and III, and to assess the effect of pH
and normal human serum (NHS) on MPO adsorption. MPO III adsorbed
preferentially (i) at high bacterial concentrations, (ii) in the pH range
of 6.0-8.0, and (iii) in the presence and absence of NHS. These results
support the role of MPO III in the killing of oral bacteria.
