Parasites of the genus Plasmodium, the etiological agent of malaria, are transmitted through the bite of anopheline mosquitoes, which deposit sporozoites into the host skin. Sporozoites migrate through the dermis, enter the bloodstream, and rapidly traffic to the liver. They cross the liver sinusoidal barrier and traverse several hepatocytes before switching to productive invasion of a final one for replication inside a parasitophorous vacuole. Cell traversal and productive invasion are functionally independent processes that require proteins secreted from specialized secretory organelles known as micronemes. In this review, we summarize the current understanding of how sporozoites traverse through cells and productively invade hepatocytes, and discuss the role of environmental sensing in switching from a migratory to an invasive state. We propose that timely controlled secretion of distinct microneme subsets could play a key role in successful migration and infection of hepatocytes. A better understanding of these essential biological features of the Plasmodium sporozoite may contribute to the development of new strategies to fight against the very first and asymptomatic stage of malaria.

中文翻译：

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移动中的疟原虫子孢子：从细胞穿越转变为对肝细胞的生产性侵袭

疟原虫属寄生虫，疟疾的病原体，通过按蚊叮咬传播，按蚊将子孢子沉积到宿主皮肤中。子孢子通过真皮迁移，进入血液，并迅速进入肝脏。它们穿过肝脏正弦屏障并穿过几个肝细胞，然后切换到最后一个的生产性入侵，以便在寄生液泡内进行复制。细胞穿越和生产性入侵是功能独立的过程，需要从称为微线体的专门分泌细胞器分泌的蛋白质。在这篇综述中，我们总结了目前对子孢子如何穿过细胞并有效侵入肝细胞的理解，并讨论了环境感知在从迁移状态转变为侵入状态中的作用。我们建议及时控制不同微线体亚群的分泌可以在肝细胞的成功迁移和感染中发挥关键作用。更好地了解这些基本的生物学特征疟原虫子孢子可能有助于制定新的战略来对抗疟疾的最初阶段和无症状阶段。