Université de Poitiers, Laboratoire Ecologie et Biologie des Interactions, UMR Centre National de la Recherche Scientifique 7267, Equipe Microbiologie de l'Eau, Poitiers, France.
Institut National de la Recherche Agronomique, Université de Tours, UMR1282, Infectiologie et Santé Publique, Nouzilly, France.
Front Cell Infect Microbiol. 2018 Feb 9;8:28. doi: 10.3389/fcimb.2018.00028. eCollection 2018.
subsp. is responsible for paratuberculosis in animals. This disease, leading to an inflammation of the gastrointestinal tract, has a high impact on animal health and an important economic burden. The environmental life cycle of subsp. is poorly understood and several studies suggest that free-living amoebae (FLA) might be a potential environmental host. FLA are protozoa found in water and soil that are described as reservoirs of pathogenic and non-pathogenic bacteria in the environment. Indeed, bacteria able to survive within these amoebae would survive phagocytosis from immune cells. In this study, we assessed the interactions between several strains of subsp. and . The results indicate that the bacteria were able to grow within the amoeba and that they can survive for several days within their host. To explore the presence of subsp. in environmental amoebae, we sampled water from farms positive for paratuberculosis. A subsp. strain was detected within an environmental amoeba identified as related to the poorly described genus. The bacterial strain was genotyped, showing that it was similar to previous infectious strains isolated from cattle. In conclusion, we described that various subsp. strains were able to grow within amoebae and that these bacteria could be found on farm within amoebae isolated from the cattle environment. It validates that infected amoebae might be a reservoir and vector for the transmission of subsp. .
亚种是导致动物感染副结核病的原因。这种疾病会导致胃肠道炎症，对动物健康有很大影响，同时也带来了重要的经济负担。亚种的环境生命周期还没有得到充分的了解，有几项研究表明自由生活的变形虫（FLA）可能是潜在的环境宿主。FLA 是一种存在于水和土壤中的原生动物，被描述为环境中致病性和非致病性细菌的储存库。事实上，能够在这些变形虫中存活的细菌能够在被免疫细胞吞噬后存活下来。在这项研究中，我们评估了几个亚种菌株与. 的相互作用。结果表明，细菌能够在变形虫内生长，并且能够在其宿主内存活数天。为了探索环境变形虫中是否存在亚种，我们从患有副结核病的农场采集水样。在一种被鉴定为与描述不佳的属相关的环境变形虫中检测到了一个亚种菌株。对该细菌菌株进行了基因分型，结果表明它与以前从牛身上分离出的传染性菌株相似。总之，我们描述了各种亚种菌株能够在变形虫内生长，并且这些细菌可以在从牛环境中分离出的变形虫内的农场中找到。这验证了感染的变形虫可能是亚种传播的储主和媒介。
