Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
FEMS Microbiol Lett. 2009 Nov;301(1):103-8. doi: 10.1111/j.1574-6968.2009.01799.x. Epub 2009 Sep 21.
The protozoan parasite Toxoplasma gondii infects its host cells through an active mechanism. In this work, we obtained evidence that host cells also play a fundamental role during the infection process. We found that previous incubation of the host cells, but not the parasites, with Dynasore, a small molecule that inhibits dynamin GTPase activity, markedly reduced the penetration of T. gondii tachyzoites into LLC-MK2 cells. In contrast, parasite adhesion to the host cell surface increased, as observed both by light and electron microscopy. Intriguingly, the few parasites internalized by Dynasore-treated cells remained in vacuoles located at the periphery of the cell, in contrast to the perinuclear localization seen in the control.
原虫寄生虫刚地弓形虫通过主动机制感染宿主细胞。在这项工作中，我们获得了证据表明宿主细胞在感染过程中也起着至关重要的作用。我们发现，宿主细胞而不是寄生虫预先与 Dynasore 孵育，Dynasore 是一种抑制动力蛋白 GTP 酶活性的小分子，可显著降低刚地弓形虫速殖子侵入 LLC-MK2 细胞。相比之下，寄生虫与宿主细胞表面的粘附增加，这一点无论是通过光镜还是电子显微镜都可以观察到。有趣的是，用 Dynasore 处理的细胞内吞噬的少数寄生虫仍留在位于细胞周边的空泡中，与对照中观察到的核周定位形成对比。
