CNRS, UMR 8076 BioCis, University Paris-Saclay, Châtenay-Malabry, France.
Institut Paris-Saclay d'Innovation Thérapeutique (IPSIT), UMS -US31 -UMS3679, Microscopy facility (MIPSIT), University Paris-Saclay, Châtenay-Malabry, France.
Cell Microbiol. 2020 Sep;22(9):e13218. doi: 10.1111/cmi.13218. Epub 2020 Jun 28.
We conducted a study to decipher the mechanism of the formation of the large communal Leishmania amazonensis-containing parasitophorous vacuole (PV) and found that the macrophage microtubule (MT) network dynamically orchestrates the intracellular lifestyle of this intracellular parasite. Physical disassembly of the MT network of macrophage-like RAW 264.7 cells or silencing of the dynein gene, encoding the MT-associated molecular motor that powers MT-dependent vacuolar movement, by siRNA resulted in most of the infected cells hosting only tight parasite-containing phagosome-like vacuoles randomly distributed throughout the cytoplasm, each insulating a single parasite. Only a minority of the infected cells hosted both isolated parasite-containing phagosome-like vacuoles and a small communal PV, insulating a maximum of two to three parasites. The tight parasite-containing phagosome-like vacuoles never matured, whereas the small PVs only matured to a small degree, shown by the absence or faint acquisition of host-cell endolysosomal characteristics. As a consequence, the parasites were unable to successfully complete promastigote-to-amastigote differentiation and died, regardless of the type of insulation.
我们进行了一项研究，以破译大型共生利什曼原虫（Leishmania amazonensis）含有的吞噬空泡（PV）形成的机制，发现巨噬细胞微管（MT）网络动态协调这种细胞内寄生虫的细胞内生活方式。通过 siRNA 破坏巨噬细胞样 RAW 264.7 细胞中的 MT 网络或沉默编码驱动 MT 依赖性液泡运动的 MT 相关分子马达的动力蛋白基因，导致大多数感染细胞仅容纳紧密的含有寄生虫的吞噬体样空泡，这些空泡随机分布在细胞质中，每个空泡隔离一个寄生虫。只有少数感染细胞既容纳孤立的含有寄生虫的吞噬体样空泡，又容纳一个小的共生 PV，最多可隔离两到三个寄生虫。紧密的含有寄生虫的吞噬体样空泡从未成熟，而小的 PV 仅成熟到很小的程度，表现为缺乏或微弱获得宿主细胞内溶酶体的特征。结果，寄生虫无法成功完成前鞭毛体到无鞭毛体的分化并死亡，无论隔离类型如何。
