Murine model for analysis of the immune response to oral colonization

The overall aim of this work was to analyze the role of the immune response to a known periodontal pathogen, Actinomyces viscosus T14V, in orally superinfected Balb/c mice. The mice did not contain A. viscosus in the oral cavity prior to superinfection. Colonization by superinfecting A. viscosus was specific for the tooth surface. When mice were placed on a soft, high‐carbohydrate diet and superinfected with varying doses of A. viscosus T14VJ1, all mice became infected. A cell‐mediated response to the bacteria was detected only in the low‐dose inoculated animals, and only the low‐dose mice developed bone loss. No serum antibody to the bacteria was detected in any animal. The response to the bacteria was detected in the cervical lymph nodes, which are the draining lymph nodes for the gingival tissue. The results suggest that the development of an immune response to the periodontal pathogen, A. viscosus T14V, correlated with bone loss in super‐infected mice.