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Investigating the Phagocytosis of Leishmania using Confocal Microscopy
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Apoptosis and apoptotic mimicry: the Leishmania connection
João Luiz M Wanderley1, Marcello A Barcinski
1Division of Experimental Medicine, National Cancer Institute, Rio de Janeiro, Brazil.
Cellular and Molecular Life Sciences : CMLS
|February 9, 2010
Summary
Unicellular organisms exhibit diverse death styles, some mimicking animal cell apoptosis via phosphatidylserine (PS) exposure. Leishmania amazonensis displays distinct PS exposure mechanisms in different life stages, termed apoptotic mimicry.
Area of Science:
- Cell Biology
- Parasitology
- Biochemistry
Background:
- Unicellular organisms display death mechanisms resembling animal cell apoptosis, including phosphatidylserine (PS) exposure.
- The precise biochemical pathways governing cell death in unicellular organisms remain incompletely understood.
- Host recognition of PS on parasitic unicellular organisms is crucial for infection and disease progression.
Purpose of the Study:
- To investigate the mechanisms of PS exposure in Leishmania amazonensis during its life cycle.
- To explore the phenomenon of "apoptotic mimicry" in unicellular parasites.
- To discuss the role of caspase-like activities in protozoan cell death.
Main Methods:
- Analysis of PS exposure in different life stages of Leishmania amazonensis (promastigotes and amastigotes).
- Phenotypic characterization of cell death markers.
- Review of existing literature on protozoan cell death and caspase-like activities.
Main Results:
- Leishmania amazonensis promastigotes exhibit a sub-population undergoing apoptosis with PS exposure.
- Leishmania amazonensis amastigotes show a distinct mechanism where the entire population exposes PS, not necessarily leading to apoptotic death.
- This differential PS exposure phenomenon is termed apoptotic mimicry.
Conclusions:
- Leishmania amazonensis employs distinct mechanisms for PS exposure during its life cycle.
- Apoptotic mimicry is a significant survival strategy for unicellular parasites.
- Further research is needed to elucidate the biochemical pathways and caspase-like activities involved in protozoan cell death.
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