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In Vivo Infection with Leishmania amazonensis to Evaluate Parasite Virulence in Mice
Published on: February 20, 2020
Finding Leishmania: a deadly game of hide-and-seek
1Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA. pscott@vet.upenn.edu
Cell Host & Microbe
|July 21, 2009
Abstract:
Leishmaniasis is a chronic infection in which intracellular parasites avoid destruction by the immune system. Using intravital imaging, Filipe-Santos et al. (2009) demonstrate that some parasitized dendritic cells receive much less attention than others during their choreographed dance with T cells, suggesting that these "wallflowers" could allow for parasite survival.
Insights
Leishmaniasis parasites survive by hiding within dendritic cells that avoid T cell interactions. These "wallflower" cells evade immune detection, allowing the chronic infection to persist.
Area of Science:
- Immunology
- Cell Biology
- Infectious Diseases
Background:
- Leishmaniasis is a chronic parasitic infection where intracellular protozoa evade host immune responses.
- Dendritic cells are crucial antigen-presenting cells that initiate T cell responses.
- Understanding parasite evasion mechanisms is vital for developing effective treatments.
Discussion:
- Intravital imaging revealed that some infected dendritic cells are neglected during T cell interactions.
- This immune "wallflower" phenomenon may represent a key survival strategy for Leishmania parasites.
- Parasite persistence could be facilitated by reduced immune surveillance of specific infected cells.
Key Insights:
- Parasitized dendritic cells exhibit differential engagement with T cells.
- A subset of infected dendritic cells avoids immune cell surveillance.
- This selective immune evasion contributes to the chronicity of Leishmaniasis.
Outlook:
- Further research into the mechanisms governing "wallflower" cell selection is warranted.
- Targeting these immune-privileged infected cells could offer new therapeutic strategies.
- Investigating this interaction may shed light on other chronic infectious diseases.
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