Virulence of oral Fusobacterium nucleatum from humans and non-human primates in mice

The lethal action in Balb/c mice of 80 oral Fusobacterium nucleatum recover ed from patients with adult periodontitis, healthy subjects or Cebus apella monkeys was studied. Mice were inoculated intraperitoneally with each bact erial inoculum of 5 x 10(8) CFU/ml. All the clinical isolates induced weigh t and coordinated movements loss. Pathological alterations in liver, CNS, h eart, and kidney with inflammatory reactions or vascular congestion were ob served. Of all the tested F. nucleatum isolates, 61.2% from periodontal pat ients, 57.1% from healthy subjects and 60% from monkeys, were capable of ki lling the mice in 48h. The clinical isolates were significantly more pathog enic than F. nucleatum ATCC 10953 or ATCC 25586. B. fragilis ATCC 23745 sho wed lethality against control mice. Our results suggest that LPS could be i nvolved in lethal action against mice and it may play an important role in producing tissue damage or death of mice.