[P1-2-26] Physiological dynamics of Aggregatibacter actinomycetemcomitans Persister phagocytosed by macrophages.
Keywords:Persister、Aggregatibacter actinomycetemcomitans 、マクロファージ
Periodontal bacteria persisters refer to a subset of bacteria within a biofilm that are resistant to antibiotics and host immune responses. These persister cells are able to survive and persist within the oral cavity despite various antimicrobial treatments. Periodontal bacteria phagocytosed by macrophages are phagocytosed and sterilized, but periodontal bacteria that form persisters are expected to continue to survive after phagocytosis and continue to promote the production of proinflammatory cytokines. The purpose of this study is to elucidate the physiological dynamics of the periodontal pathogen Persister and to contribute to the treatment and prevention of chronic periodontitis. Aggregatibacter actinomycetemcomitans Y4, which cause rapidly progressing periodontitis. THP-1, a human monocytic leukemia-derived cell, was stimulated with PMA (phorbol 12-myristate 13-acetate) overnight, washed with PBS, and cultured in RPMI 1640 culture medium with 5% FBS for 2 days. Determine the appropriate conditions for the number of bacteria and time to infect THP-1 cells with A. actinomycetemcomitans Y4 differentiated into macrophages. Survival rate of exponential state A. actinomycetemcomitans Y4 and hydrogen peroxide-treated A. actinomycetemcomitans Y4 persister inside macrophages was examined. We also plan to analyze changes in gene expression of periodontopathic bacteria and macrophages before and after phagocytosis by macrophages to examine the mechanisms by which bacteria evade phagocytosis and macrophages elicit inflammatory responses at the genetic level. We also plan to elucidate the detailed mechanism by mRNA expression analysis using next-generation sequencers, analysis of persister-related genes in bacteria, and analysis of cytokine production-related genes in macrophages. This study proposes a new concept that Persister is involved in the recurrence and chronicity of periodontal disease.