Related Experiment Video
Updated: Apr 5, 2026
Detecting Wolbachia Strain wAlbB in Aedes albopictus Cell Lines
Published on: June 1, 2022
Wolbachia Do Not Induce Reactive Oxygen Species-Dependent Immune Pathway Activation in Aedes albopictus
Jennifer C Molloy1, Steven P Sinkins2
1Peter Medawar Building for Pathogen Research and Department of Zoology, University of Oxford, Oxford OX1 3SY, UK. jenny.molloy@cantab.net.
Abstract:
Aedes albopictus is a major vector of dengue (DENV) and chikungunya (CHIKV) viruses, causing millions of infections annually. It naturally carries, at high frequency, the intracellular inherited bacterial endosymbiont Wolbachia strains wAlbA and wAlbB; transinfection with the higher-density Wolbachia strain wMel from Drosophila melanogaster led to transmission blocking of both arboviruses. The hypothesis that reactive oxygen species (ROS)-induced immune activation plays a role in arbovirus inhibition in this species was examined. In contrast to previous observations in Ae. aegypti, elevation of ROS levels was not observed in either cell lines or mosquito lines carrying the wild-type Wolbachia or higher-density Drosophila Wolbachia strains. There was also no upregulation of genes controlling innate immune pathways or with antioxidant/ROS-producing functions. These data suggest that ROS-mediated immune activation is not an important component of the viral transmission-blocking phenotype in this species.
Insights
Reactive oxygen species (ROS) do not mediate arbovirus transmission blocking in Aedes albopictus mosquitoes, despite Wolbachia
Area of Science:
- Vector-borne disease research
- Microbial ecology
- Insect immunology
Background:
- Aedes albopictus mosquitoes transmit dengue (DENV) and chikungunya (CHIKV).
- Wolbachia endosymbionts can block arbovirus transmission in these mosquitoes.
- Previous studies suggested reactive oxygen species (ROS) mediate this blocking.
Purpose of the Study:
- To investigate the role of ROS-mediated immune activation in arbovirus inhibition by Wolbachia in Aedes albopictus.
Main Methods:
- Comparison of ROS levels in mosquito cell lines and whole mosquitoes with and without Wolbachia.
- Analysis of gene expression related to innate immunity and ROS production.
Main Results:
- No elevation of ROS levels was observed in Wolbachia-infected Aedes albopictus.
- No significant upregulation of innate immune or ROS-related genes was detected.
- These findings contrast with observations in Aedes aegypti.
Conclusions:
- ROS-mediated immune activation is not the primary mechanism for arbovirus transmission blocking in Aedes albopictus.
- The mechanism of Wolbachia-mediated arbovirus inhibition in this species likely differs from previously proposed pathways.
