Neutrophils in chronic and aggressive periodontitis in interaction with Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans

Background and Objective: This study analyzed the interaction of Porphyromonas gingivalis ATCC 33277 and Aggregatibacter actinomycetemcomitans Y4 with peripheral blood polymorphonuclear neutrophils taken from patients with aggressive periodontitis and chronic periodontitis. Material and Methods: Peripheral blood polymorphonuclear neutrophils obtained from 12 patients with chronic periodontitis, six patients with aggressive periodontitis and 12 healthy controls were exposed to P. gingivalis and A. actinomycetemcomitans following opsonization of the bacteria using the patient’s own serum. Serum immunoglobulin G (IgG) levels against both periodontopathogens were measured. Phagocytosis and killing of the bacteria, as well as the extracellular human neutrophil elastase activity, were quantified. The total amount and the extracellular release of reactive oxygen species were measured using luminol‐dependent and isoluminol‐dependent chemiluminescence. Results: Polymorphonuclear neutrophils from patients with chronic (62.16 ± 19.39%) and aggressive (43.26 ± 26.63%) periodontitis phagocytosed more P. gingivalis than the healthy controls (24.43 ± 19.87%) at the 30‐min time point after exposure to the bacteria (p