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Updated: Aug 9, 2026
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In Vivo Infection with Leishmania amazonensis to Evaluate Parasite Virulence in Mice
Published on: February 20, 2020
Apoptotic mimicry: an altruistic behavior in host/Leishmania interplay
J L M Wanderley1, A Benjamin, F Real
1Instituto Nacional de Câncer, 20231-050 Rio de Janeiro, RJ, Brasil.
Summary
Programmed cell death, or apoptosis, is crucial for multicellular life. This study reveals unicellular organisms like Leishmania use apoptotic features, such as phosphatidylserine exposure, for infection and survival.
Area of Science:
- Cell Biology
- Evolutionary Biology
- Parasitology
Background:
- Apoptosis, or programmed cell death, is vital for multicellular organism development and homeostasis.
- While essential for multicellular life, the role of apoptosis in unicellular organisms was unclear.
- Recent findings suggest unicellular organisms utilize apoptotic markers for population benefits and infection.
Purpose of the Study:
- To investigate the role of phosphatidylserine (PS) exposure in Leishmania infectivity.
- To explore how PS exposure modulates phagocytic cell inflammatory activity.
- To discuss the evolutionary implications of apoptosis in unicellular organisms.
Main Methods:
- Focus on phosphatidylserine (PS) exposure as an early apoptosis hallmark.
- Analysis of PS recognition by phosphatidylserine receptor (PSR).
- Examination of Leishmania amastigote infectivity and host cell interactions.
Main Results:
- Phosphatidylserine (PS) exposure is implicated in Leishmania amastigote infectivity.
- PS exposure influences the inflammatory responses of phagocytic cells.
- Unicellular organisms employ apoptotic features for infection establishment and survival.
Conclusions:
- Apoptosis and its markers, like PS exposure, are utilized by unicellular organisms, including Leishmania, for parasitic strategies.
- PS exposure plays a role in Leishmania's survival within host cells.
- The study highlights the evolutionary significance of apoptosis at the unicellular level.
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