Human immunoglobulin G2 (IgG2) responses are gamma interferon (IFN-gamma) dependent, and monocyte-derived dendritic cells (mDCs) promote IgG2 production. DCs spontaneously emerge from monocytes in cultures prepared from localized aggressive periodontitis (LagP) patients, and these patients have high levels of IgG2 that is reactive with Actinobacillus actinomycetemcomitans. These results prompte...

The invasion process of Actinobacillus actinomycetemcomitans, a periodontopathogen, was studied with microscopy and viable quantitative assays using both KB and Madin-Darby canine kidney (MDCK) epithelial cells. Microscopy revealed that the events associated with the A. actinomycetemcomitans invasion process occurred rapidly. Scanning electron micrographs revealed A. actinomycetemcomitans assoc...

Bactericidal activity of human beta-defensin 3 (hBD-3) against Streptococcus mutans and Actinobacillus actinomycetemcomitans was inhibited in a dose-dependent manner by the presence of saliva and/or serum. Increasing the concentration of hBD-3 partially overcame this inhibition. A fast bactericidal effect was observed against both bacterial strains, suggesting a potential therapeutic use for hB...

Oligodeoxynucleotide probes were developed for identification of the periodontal bacteria Actinobacillus actinomycetemcomitans, Bacteroides gingivalis, B. intermedius types I and II, B. forsythus, Eikenella corrodens, Fusobacterium nucleatum, Haemophilus aphrophilus, Streptococcus intermedius, and Wolinella recta. Probes were designed by sequencing the 16S rRNA for each bacterium, identifying h...

Actinobacillus actinomycetemcomitans has been closely associated with early-onset, severe periodontitis, and such patients often have serum immunoglobulin G (IgG) antibodies reactive with antigens of this gram-negative pathogen. We examined the functionality and potential importance of these antibodies. The opsonic activity against A. actinomycetemcomitans of sera from 30 patients with rapidly ...