Laboratory of Medical Parasitology, Central Institute of the Bundeswehr Medical Service Koblenz, Andernacherstr. 100, 56070 Koblenz, Germany.
Parasitol Res. 2012 Jul;111(1):479-85. doi: 10.1007/s00436-012-2828-7.
Adenoviruses are important pathogens which are responsible for human enteritic, respiratory and eye infections. These viruses have been found to be prevalent in several natural and artificial water reservoirs worldwide. Free-living amoebae (FLA) have been recovered from similar water reservoirs, and it has been shown that FLA may act as reservoirs or vehicles of various microorganisms living in the same environment. To examine the ability of FLA to harbour adenoviruses, an in vitro study was conducted. Several Acanthamoeba strains were ‘co-cultivated’ with adenoviruses (adenoviruses 11 and 41), grown on A549 cells, using a proven test protocol. After phagocytosis and ingestion, the adenoviruses could be found within the cytoplasm of the Acanthamoeba trophozoites. The intake of the viruses into the cytoplasm of the trophozoites was demonstrated in an Acanthamoeba castellanii strain with the help of fluorescence microscopy and electron microscopy. An adenovirus DFA kit, which utilizes a direct immunofluorescent antibody technique for identifying adenovirus in infected tissue cultures, was used. In our study, it was demonstrated that adenoviruses were incorporated into the host amoebae (Acanthamoeba sp. Grp. II, three strains). So far, there were only a few publications concerning the relationship of free-living amoebae and viruses; only one of these described the detection of adenoviruses within acanthamoebae with molecular biological methods. We conducted this descriptive study to further examine the association between viable adenoviruses and FLA. To our knowledge, this is the first study to demonstrate directly the adenoviruses within FLA as vectors and vehicles. Therefore, we concluded that free-living amoebae appear able to act as carriers or vectors of the adenoviruses and thus may play a certain role in the dispersal of adenoviruses.
腺病毒是重要的病原体，可引起人类肠道、呼吸道和眼部感染。这些病毒已在世界范围内的多个天然和人工水水库中被发现。从类似的水库中回收了自由生活的阿米巴原虫（FLA），并表明 FLA 可能作为生活在同一环境中的各种微生物的储存库或载体。为了研究 FLA 携带腺病毒的能力，进行了一项体外研究。使用经过验证的测试方案，将几种棘阿米巴菌株与腺病毒（腺病毒 11 和 41）“共培养”，在 A549 细胞上生长。在吞噬和摄入后，腺病毒可以在棘阿米巴滋养体的细胞质中找到。借助荧光显微镜和电子显微镜，在一株棘阿米巴castellanii 菌株中证明了病毒被摄入滋养体细胞质中。使用腺病毒 DFA 试剂盒，该试剂盒利用直接免疫荧光抗体技术鉴定感染组织培养物中的腺病毒。在我们的研究中，证明了腺病毒被整合到宿主阿米巴虫（棘阿米巴属 Grp. II，三株）中。到目前为止，只有少数关于自由生活的阿米巴虫和病毒之间关系的出版物；其中只有一份描述了用分子生物学方法在棘阿米巴虫中检测到腺病毒。我们进行了这项描述性研究，以进一步研究活腺病毒与 FLA 之间的关联。据我们所知，这是第一项直接证明 FLA 中腺病毒作为载体和车辆的研究。因此，我们得出结论，自由生活的阿米巴虫似乎能够作为腺病毒的载体或载体，因此可能在腺病毒的传播中发挥一定作用。
