化脓性真菌会在牛中引起疾病,绵羊,山羊和猪,并偶尔参与世界范围内的人类疾病。大多数涉及化脓性嗜酸杆菌的报告与临床病例有关,而没有报道集中在小鼠模型或猪精确切割肺切片(PCLS)培养物中化脓性芽孢杆菌的致病性。这里,我们分离并鉴定了一种毒力,β-溶血,多药耐药化脓性芽孢杆菌菌株命名为20121,具有毒力标记基因fima,FIME,nanH,nanP和plo.发现它对红霉素有很强的抗性,阿奇霉素和甲霉素。菌株20121在小鼠感染模型中具有致病性,显示肺充血和炎症细胞浸润,气管和支气管粘膜上皮细胞部分变性,粘膜下层有少量炎症细胞浸润,和肺中的细菌(>104CFU/g)。重要的是,我们首次使用化脓杆菌20121感染猪精确切肺切片(PCLS)培养物,导致了严重的支气管收缩.此外,地塞米松显示其缓解由化脓性嗜酸杆菌引起的PCLS支气管收缩的能力20121,强调地塞米松可能有助于临床化脓性嗜酸杆菌感染的抗生素治疗。这是在猪PCLS中用于感染和引起支气管收缩的化脓杆菌的第一份报告。我们的结果表明,猪PCLS培养物作为一种有价值的3D器官模型,用于研究化脓性T.pyogenes感染和体外治疗。
Trueperella pyogenes causes disease in cattle, sheep, goats and swine, and is involved occasionally in human disease worldwide. Most reports implicating T. pyogenes have been associated with clinical cases, whereas no report has focused on pathogenicity of T. pyogenes in mouse models or precision-cut lung slice (PCLS) cultures from swine. Here, we isolated and identified a virulent, β-hemolytic, multidrug-resistant T. pyogenes strain named 20121, which harbors the virulence marker genes fimA, fimE, nanH, nanP and plo. It was found to be highly resistant to erythromycin, azithromycin and medemycin. Strain 20121 was pathogenic in mouse infection models, displaying pulmonary congestion and inflammatory cell infiltration, partial degeneration in epithelial cells of the tracheal and bronchiolar mucosa, a small amount of inflammatory cell infiltration in the submucosa, and bacteria (>104 CFU/g) in the lung. Importantly, we used T. pyogenes 20121 to infect porcine precision-cut lung slices (PCLS) cultures for the first time, where it caused severe
bronchoconstriction. Furthermore, dexamethasone showed its ability to relieve
bronchoconstriction in PCLS caused by T. pyogenes 20121, highlighting dexamethasone may assist antibiotic treatment for clinical T. pyogenes infection. This is the first report of T. pyogenes used to infect and cause
bronchoconstriction in porcine PCLS. Our results suggest that porcine PCLS cultures as a valuable 3D organ model for the study of T. pyogenes infection and treatment in vitro.