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Updated: May 20, 2026
Detecting Wolbachia Strain wAlbB in Aedes albopictus Cell Lines
Published on: June 1, 2022
Wolbachia induces density-dependent inhibition to dengue virus in mosquito cells
Peng Lu1, Guowu Bian, Xiaoling Pan
1Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan, USA.
Abstract:
Wolbachia is a maternal transmitted endosymbiotic bacterium that is estimated to infect up to 65% of insect species. The ability of Wolbachia to both induce viral interference and spread into mosquito vector population makes it possible to develop Wolbachia as a biological control agent for dengue control. While Wolbachia induces resistance to dengue virus in the transinfected Aedes aegypti mosquitoes, a similar effect was not observed in Aedes albopictus, which naturally carries Wolbachia infection but still serves as a dengue vector. In order to understand the mechanism of this lack of Wolbachia-mediated viral interference, we used both Ae. albopictus cell line (Aa23) and mosquitoes to characterize the impact of Wolbachia on dengue infection. A serial of sub-lethal doses of antibiotic treatment was used to partially remove Wolbachia in Aa23 cells and generate cell cultures with Wolbachia at different densities. We show that there is a strong negative linear correlation between the genome copy of Wolbachia and dengue virus with a dengue infection completely removed when Wolbacha density reaches a certain level. We then compared Wolbachia density between transinfected Ae. aegypti and naturally infected Ae. albopictus. The results show that Wolbachia density in midgut, fatbody and salivary gland of Ae. albopictus is 80-, 18-, and 24-fold less than that of Ae. aegypti, respectively. We provide evidence that Wolbachia density in somatic tissues of Ae. albopictus is too low to induce resistance to dengue virus. Our results will aid in understanding the mechanism of Wolbachia-mediated pathogen interference and developing novel methods to block disease transmission by mosquitoes carrying native Wolbachia infections.
Insights
Wolbachia bacteria can block dengue virus in Aedes aegypti mosquitoes. However, lower Wolbachia density in Aedes albopictus prevents this viral interference, hindering dengue control efforts.
Area of Science:
- Microbiology
- Vector-borne disease research
- Insect pathology
Background:
- Wolbachia, an endosymbiotic bacterium, infects many insects and shows potential for biological control of dengue.
- Transinfected Aedes aegypti mosquitoes exhibit dengue virus resistance, but naturally infected Aedes albopictus do not, despite carrying Wolbachia.
Purpose of the Study:
- To investigate why Wolbachia does not confer dengue resistance in Aedes albopictus.
- To understand the mechanism of Wolbachia-mediated viral interference and its density-dependent effects.
Main Methods:
- Used antibiotic treatment to create Aedes albopictus cell lines (Aa23) with varying Wolbachia densities.
- Quantified Wolbachia genome copies and dengue virus levels in cell lines and mosquito tissues (midgut, fatbody, salivary gland).
- Compared Wolbachia densities between transinfected Ae. aegypti and naturally infected Ae. albopictus.
Main Results:
- A negative linear correlation was observed between Wolbachia density and dengue virus levels, with complete viral clearance at high Wolbachia densities.
- Wolbachia density in Ae. albopictus tissues was significantly lower (80-fold in midgut, 18-fold in fatbody, 24-fold in salivary gland) than in Ae. aegypti.
- Low Wolbachia density in Ae. albopictus somatic tissues is insufficient to induce dengue virus resistance.
Conclusions:
- Wolbachia density is critical for its ability to interfere with dengue virus replication.
- The naturally low Wolbachia infection density in Ae. albopictus explains its inability to resist dengue.
- Findings offer insights for developing novel dengue control strategies targeting mosquitoes with native Wolbachia infections.
