Polydnaviruses: potent mediators of host insect immune dysfunction
1Department of Biology, University of California-Riverside, 92521-0314, USA.
Parasitology Today (Personal Ed.)
|October 1, 1995
Summary
Insect parasitoids use polydnaviruses (PDVs) to suppress host immunity for survival. Later stages may involve other immunoevasion tactics like antigen masking or inhibitor production.
Area of Science:
- Entomology
- Immunology
- Virology
Background:
- Endoparasitic insects are vital biological control agents.
- Parasitoid success relies on host immune system suppression.
- Polydnaviruses (PDVs) are key mediators of immunosuppression in many wasp species.
Purpose of the Study:
- To review mechanisms of PDV-induced immunosuppression in insects.
- To explore the role of wasp ovarian proteins and venom in immune suppression.
- To understand immunoevasion strategies during later parasitoid development.
Main Methods:
- Review of existing scientific literature on PDVs and insect immunity.
- Analysis of viral-host genetic interactions.
- Examination of cellular and humoral immune responses in parasitized insects.
Main Results:
- PDVs, integrated into wasp DNA, induce host immunosuppression.
- Wasp ovarian proteins and venom also contribute to immune suppression.
- Early PDV-induced immunosuppression may be transitory, with later strategies employed by larvae.
Conclusions:
- PDVs are crucial for initial host immune evasion by parasitoids.
- Parasitoids utilize a multi-faceted approach to overcome host defenses.
- Understanding these mechanisms enhances biological control strategies.
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