Interactions between serum titres to filamentous bacteria and their relationship to human periodontal disease

Abstract

Sera from patients with localized gingivitis and periodontitis were examined by indirect immunofluorescence for antibodies to strains of Actinomyces israelii. Actinomyces naeslundii, Bacterionema matruchotii, Eubacterium saburreum, Leptotrichia buccalis and an unidentified filament. Antibodies to three or more strains of differing genera were present in all sera, but the titres to the individual microorganisms varied widely both within and between subjects. Antibody responses to some microorganisms were greater than or dominant to responses to other microorganisms, both in terms of consistency of response in all subjects tested and in the titres. This dominance of antibody response to some microorganisms was found in comparisons made across genera, across species, and even between strains within currently recognized species. Both simple and complex relationships in titre were found between antibody responses to two, three and four different microorganisms, but significant relationships were not found between intra-species isolates. The incidence of high-titre sera was significantly greater from periodontitis than from gingivitis patients. However, differential diagnosis between the two classes of periodontal disease could not be made reliably on the basis of specific serum titres to either individual or pairs of microorganisms because of variability in titre within each class of subjects.