Direct modulation of human neutrophil adherence by coaggregating periodontopathic bacteria.

Direct interaction between Fusobacterium nucleatum and PMNs produced consistent enhancement of PMN adherence. In contrast, consistent suppression of PMN adherence was observed after direct interactions between PMNs and Bacteroides gingivalis or Actinomyces viscosus. The modulatory effects of these periodontopathic bacteria on PMN function could be seen as early as 2 min after interaction. The effects were abrogated by alterations of bacterial structural integrity with heat, formalin or ultrasonic disruption. Carbohydrate or glycoprotein receptors on PMNs may be involved because the effects were blocked by monosaccharides in the medium. Coaggregation experiments showed that permutations involving F. nucleatum always resulted in enhancement of PMN adherence, and that this can be blocked by D-galactose. These findings may have implications in the initiation and sustenance of chronic inflammatory tissue damage in periodontitis.