Pacheco-Soares C, De Souza W
Laboratório de Biologia Celular e Tecidual, Centro de Biociências e Biotecnologia, Universidade Estadual, Rio de Janeiro, Brasil.
Cell Struct Funct. 1998 Jun;23(3):159-68. doi: 10.1247/csf.23.159.
The initial association of tachyzoites of Toxoplasma gondii with a host cell induces an endocytic process which leads to the formation of a vacuole known as the parasitophorous vacuole (PV). We analyzed the parasite-host cell interaction process using either parasites or host cells whose membrane was previously labeled with probes specific for proteins, sialoglycoconjugates and lipids, and then allowed to interact for periods varying from 5 minutes to 24 hours. The fate of the fluorescents probes was followed by confocal laser scanning microscopy. In host cells previously labeled with PKH26, FITC-Thiosemicarbazide or DTAF, which label membrane proteins, siloglycoconjugates and lipids, respectively, a uniform labeling of the cell surface was observed before interaction. When allowed to interact with T. gondii, labeling for PKH26 and DTAF, but not for FITC-Thiosemicarbazide, was observed initially at the region of contact between the two cells and subsequently on the membrane lining the PV and the intravacuolar parasites. These observations show that some, but not all, membrane components contribute to the formation of the PV membrane. Previously labeled parasites attach to the host cell surface but lose the fluorescent probes during the invasion process so that no labeled parasites were seen within the PV. These observations point to the existence of a dynamic process of membrane-associated components of the parasite and host cell during the interaction process.
刚地弓形虫速殖子与宿主细胞的初始结合会引发一个内吞过程，该过程导致形成一个称为寄生泡（PV）的液泡。我们使用寄生虫或宿主细胞来分析寄生虫与宿主细胞的相互作用过程，这些寄生虫或宿主细胞的膜先前已用针对蛋白质、唾液糖缀合物和脂质的特异性探针进行标记，然后让它们相互作用5分钟至24小时不等。通过共聚焦激光扫描显微镜观察荧光探针的命运。在先前用PKH26、FITC-硫代半卡巴腙或DTAF标记的宿主细胞中，它们分别标记膜蛋白、唾液糖缀合物和脂质，在相互作用之前观察到细胞表面有均匀的标记。当与刚地弓形虫相互作用时，最初在两个细胞的接触区域观察到PKH26和DTAF的标记，但未观察到FITC-硫代半卡巴腙的标记，随后在PV内衬膜和泡内寄生虫上也观察到了这种标记。这些观察结果表明，一些但不是所有的膜成分都有助于PV膜的形成。先前标记的寄生虫附着在宿主细胞表面，但在入侵过程中失去荧光探针，因此在PV内未见到标记的寄生虫。这些观察结果表明在相互作用过程中寄生虫和宿主细胞膜相关成分存在动态过程。
