Imaging Host Cell-Leishmania Interaction Dynamics Implicates Parasite Motility, Lysosome Recruitment, and Host Cell Wounding in the Infection Process

Claire-Lise Forestier et al., 2011, Cell Host & Microbe Journal 9: 319-330

Speaker: Chiung-Chen Chou (周炯呈)                         Time: 15:00~16:00, Dec. 7, 2011

Commentator: Dr. Chih-Li Hsu (胥直利老師)             Place: Room 601

Abstract

The major host of Leishmania donavani is mammalian, when human infected with this parasite will cause visceral leishmanisis. The infective ability of L. donavani only exist when it transform amastigote into promastigote. Macrophages, the phagocytic and antigen presenting cells play an important role in innate immunity, are the major target of the Leishmania promastigote. In L. donavani infection stage, the author found that most promastigotes enter macrophages initiated by their flagellum tip. Leishmania could generate the biogenesis of parasitophorous vacuole (PV) which was fusion with lysosome in the early infection phase. In contrast, after promastigotes were engulfed by the macrophages, they became resistant to fusion with lysosomes. In this article, we can find out the trajectory of the infection process by the imaging. Although a lot of studies have showed numerous information about lysosomal degration, surprisingly, this article showed lysosomes being the resources for wounding repairing of the host cell after parasite with the flagellum reaching outward of the macrophage. Lysosomes that docking at the parasite active site with wounding phenomenon could be exocytosis by the host cell. Therefore, this article revealed the different character of the lysosomes in the phagocytosis and used the powerful evidences to confirm the Leishmania infection steps that were poorly elucidated by earlier studies.

References

1.      Paul Kaye et al., Leishmanisis: complexity at the host-pathogen interface. Nature Reviews Microbiology 9, 604-615 (2011)