Rusconi Brigida, Kebbi-Beghdadi Carole, Greub Gilbert
Institute of Microbiology, University of Lausanne and University Hospital Center, Lausanne, 1011, Switzerland.
Institute of Microbiology, University of Lausanne and University Hospital Center, Lausanne, 1011, Switzerland
Pathog Dis. 2015 Jul;73(5). doi: 10.1093/femspd/ftv027. Epub 2015 Apr 9.
Estrella lausannensis is a new member of the Chlamydiales order. Like other Chlamydia-related bacteria, it is able to replicate in amoebae and in fish cell lines. A preliminary study investigating the pathogenic potential of Chlamydia-related bacteria found a correlation between antibody response to E. lausannensis and pneumonia in children. To further investigate the pathogenic potential of E. lausannensis, we determined its ability to grow in human macrophages and its intracellular trafficking. The replication in macrophages resulted in viable E. lausannensis; however, it caused a significant cytopathic effect. The intracellular trafficking of E. lausannensis was analyzed by determining the interaction of the Estrella-containing inclusions with various endocytic markers as well as host organelles. The E. lausannensis inclusion escaped the endocytic pathway rapidly avoiding maturation into phagolysosomes by preventing both EEA-1 and LAMP-1 accumulation. Compared to Waddlia chondrophila, another Chlamydia-related bacteria, the recruitment of mitochondria and endoplasmic reticulum was minimal for E. lausannensis inclusions. Estrella lausannensis appears to use a distinct source of nutrients and energy compared to other members of the Chlamydiales order. In conclusion, we hypothesize that E. lausannensis has a restricted growth in human macrophages, due to its reduced capacity to control programmed cell death.
劳桑纳埃氏菌是衣原体目新成员。与其他衣原体相关细菌一样，它能够在变形虫和鱼类细胞系中复制。一项调查衣原体相关细菌致病潜力的初步研究发现，儿童对劳桑纳埃氏菌的抗体反应与肺炎之间存在关联。为进一步研究劳桑纳埃氏菌的致病潜力，我们测定了其在人类巨噬细胞中的生长能力及其细胞内运输情况。在巨噬细胞中的复制产生了活的劳桑纳埃氏菌；然而，它引起了显著的细胞病变效应。通过确定含埃氏菌包涵体与各种内吞标记物以及宿主细胞器的相互作用，分析了劳桑纳埃氏菌的细胞内运输情况。劳桑纳埃氏菌包涵体迅速逃离内吞途径，通过阻止早期内体抗原1（EEA-1）和溶酶体相关膜蛋白1（LAMP-1）的积累来避免成熟为吞噬溶酶体。与另一种衣原体相关细菌嗜软骨沃氏菌相比，劳桑纳埃氏菌包涵体对线粒体和内质网的募集极少。与衣原体目的其他成员相比，劳桑纳埃氏菌似乎利用不同的营养和能量来源。总之，我们推测劳桑纳埃氏菌在人类巨噬细胞中的生长受限，是由于其控制程序性细胞死亡的能力降低。
