Vouga Manon, Baud David, Greub Gilbert
Materno-fetal and Obstetrics Research Unit, Department 'Femme-Mère-Enfant', Maternity, University Hospital, 1011 Lausanne, Switzerland.
Center for Research on Intracellular Bacteria, Institute of Microbiology, Faculty of Biology and Medicine, University of Lausanne and University Hospital, 1011 Lausanne, Switzerland.
Pathog Dis. 2017 Jan 1;75(1). doi: 10.1093/femspd/ftw115.
Simkania negevensis is a novel Chlamydia-related bacterium and the founding member of the Simkaniaceae family within the Chlamydiales order. Little is known about the biology and pathogenesis of this bacterium. So far, S. negevensis has been considered as an amoebal symbiont, but its natural host remains unknown. Moreover, evidence of human exposition has been reported worldwide and an association with pneumonia and bronchiolitis is suspected. Here, we evaluated the ability of S. negevensis to replicate in potential environmental reservoirs, namely amoebae and arthropods, as well as in mammalian cells (Vero cells, pneumocytes and endometrial cells) and further evaluated the characteristics of its replicative vacuole. We demonstrated that S. negevensis efficiently replicates in all cell lines tested, with the shortest doubling time and an increased adhesion observed in pneumocytes. Our work highlights the specificities of the Simkania-containing vacuole compared to other Chlamydiales; contrarily to Chlamydia trachomatis, S. negevensis does not disrupt the Golgi apparatus. Importantly, our work suggests that S. negevensis infection is associated with few cytopathic effects and might persist for a prolonged time in infected cells. Further evaluation of its implication in human diseases is required; an implication in chronic or subacute respiratory infections might be suspected.
内格夫希曼菌是一种与衣原体相关的新型细菌，是衣原体目希曼菌科的创始成员。关于这种细菌的生物学特性和发病机制知之甚少。到目前为止，内格夫希曼菌一直被认为是一种阿米巴共生菌，但其天然宿主仍不清楚。此外，全球范围内都有人类接触该菌的报道，并且怀疑它与肺炎和细支气管炎有关。在此，我们评估了内格夫希曼菌在潜在环境宿主（即阿米巴和节肢动物）以及哺乳动物细胞（Vero细胞、肺细胞和子宫内膜细胞）中复制的能力，并进一步评估了其复制泡的特征。我们证明，内格夫希曼菌能在所有测试的细胞系中有效复制，在肺细胞中观察到最短的倍增时间和增强的黏附。我们的研究突出了含希曼菌的液泡与其他衣原体相比的特异性；与沙眼衣原体不同，内格夫希曼菌不会破坏高尔基体。重要的是，我们的研究表明，内格夫希曼菌感染与很少的细胞病变效应有关，并且可能在受感染细胞中持续较长时间。需要进一步评估其在人类疾病中的影响；可能怀疑它与慢性或亚急性呼吸道感染有关。
