[ODP25] 5. 病原性-e. 感染モデル

[ODP-157] ジンジバリス菌の成分/分泌物は肺炎球菌感染により誘発される肺炎を増悪化する

岡部 徹平¹，神谷 洋介¹，菊池 毅¹，梅村 正幸²，杉田 好彦³，内記 良一⁴，長谷川 義明⁴，林 潤一郎¹，樋口 直也⁵，三谷 章雄¹ (¹愛知学院大・歯・歯周病，²琉球大・熱生研・感染防御，³愛知学院大・歯・口腔病理，⁴愛知学院大・歯・微生物，⁵愛知学院大・歯・歯内治療)

Streptococcus pneumonia (Sp) is the main pathogens causing pneumonia. Although periodontal bacteria have been shown to influence respiratory infections such as aspiration pneumonia, the synergistic effect of Sp and Porphyromonas gingivalis (Pg), a periodontopathic bacterium, on pneumococcal infections is unclear. To investigate whether Pg accelerates pneumococcal infections, we tested the effect of inoculating Pg culture supernatant (PgSup) into Sp-infected mice. Mice were intratracheally injected with Sp and PgSup to induce pneumonia, the frequency of neutrophils and macrophages in the lung and proinflammatory cytokines/chemokines expressions were examined. Inflammatory cell infiltration was observed in Sp-injected mice and Sp and PgSup mixed-injected mice, and mixed-injected mice showed more pronounced inflammation in the lungs. The ratios of monocytes/macrophages and neutrophils were slightly higher in the lungs of mixed-injected mice than those in Sp-injected mice. PgSup synergistically increased expression/production of IL-1β, TNF-α, KC, MIP-2, and IL-17A compared with Sp injection alone. We demonstrated that PgSup enhanced inflammation in pneumonia caused by Sp, suggesting that virulence factors produced by Pg are involved in the exacerbation of respiratory tract infections such as aspiration pneumonia.