Porphyromonas gingivalis enhances pneumococcal adhesion to human alveolar epithelial cells by increasing expression of host platelet ‐activating factor receptor

AbstractStreptococcus pneumoniae causes pneumonia by infecting the alveolar epithelium via binding to host receptors, such as the platelet ‐activating factor receptor (PAFR). Although chronic periodontitis has been identified as a pneumonia risk factor, how periodontopathic bacteria cause pneumonia is not known. We found thatS. pneumoniae adhered to PAFR expressed on A549 human alveolar epithelial cells stimulated byPorphyromonas gingivalis culture supernatant, and this was abrogated by a PAFR ‐specific inhibitor. Among the major virulence factors ofP. gingivalis (lipopolysaccharide, fimbriae and gingipains [Rgps and Kgp]), PAFR expression and pneumococcal adhesion were executed in an Rgp ‐dependent manner. Lipopolysaccharide and fimbriae did not induce PAFR expression. Hence, our findings suggest thatP. gingivalis enhances pneumococcal adhesion to human alveoli by inducing PAFR expression and that gingipains are responsible for this.

Source: FEBS Letters - April 1, 2021 Category: Biochemistry Authors: Noriaki Kamio, Mayumi Hayata, Muneaki Tamura, Hajime Tanaka, Kenichi Imai Tags: RESEARCH LETTER Source Type: research