Three presumed "good" bacteria—Streptococcus sanguinis, Streptococcus mitis and Streptococcus salivarius—can inhibit the colonization of the "bad" bacterium Aggregatibacter actinomycetemcomitans, reported scientists in the July issue of Journal of Dental Research.
Researchers from Catholic University Leuven, Research Group for Microbial Adhesion, Department of Periodontology, Belgium, and University of California Los Angeles, School of Dentistry, studied how good bacteria, or commensals, suppress bad, or pathogenic, bacteria’s colonization of epithelial cells. They evaluated the ability of presumed commensals to interfere, exclude or displace the oral pathogen A. actinomycetemcomitans (formerly Actinobacillus actinomycetemcomitans), which is associated strongly with juvenile periodontal disease.
Researchers, led by Dr. Wim Teughels, Catholic University Leuven, determined that three presumed commensals—S. sanguinis, S. mitis and S. salivarius—had prominent inhibitory effects on the colonization or recovery of A. actinomycetemcomitans. They also found that the commensals Actinomyces naeslundii and Haemophilus parainfluenzae helped A. actinomycetemcomitans colonize. But, as the researchers noted, "The colonization of the test strains was also affected by the pathogen, indicating that these are two-way interactions, influencing the colonization of both pathogen and test strains."
According to the authors, this study is the first to be published that describes in vitro interference of an oral pathogen’s colonization of epithelial cells.
This study was supported by a grant from the National Institute of Dental and Craniofacial Research.
