Development of a rapid latex agglutination test for periodontal pathogens

The studies reported here describe the development, characterization, and initial application of latex agglutination assays for periodontal pathogens. Latex reagents were prepared by sensitization of latex microspheres with rabbit IgG antibodies to either Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, or Prevotella intermedia. The protein concentration utilized for sensitization and microsphere size were optimized. One reagent was prepared to A. actinomycetemcomitans and a second combination reagent was prepared by mixing latex sensitized with antibodies to P. gingivalis and latex sensitized with antibodies to P. intermedia. The sensitivity of both latex reagents in the traditional wet and a dried format was evaluated. In addition, sensitivity and specificity with homologous and heterologous bacterial suspensions were evaluated. The reagents were found to demonstrate both specificity and sensitivity. Initial studies with subgingival human plaque demonstrated the ability of these reagents to detect the specific organisms in plaque.