Poster Presentation 12th Australasian Virology Society Meeting 2024

Evaluating cell:cell antiviral protection by Wolbachia in Aedes aegypti cells (#170)

Neil Katrina D Ibay 1 2 , Hayley J Newton 2 , Johanna E Fraser 1 2
  1. Arbovirology Group, Life Sciences Discipline, The Macfarlane Burnet Institute for Medical Research and Public Health, Melbourne, VIC, Australia
  2. Infection Program, Monash Biomedicine Institute and Department of Microbiology, Monash University, Clayton, Victoria, Australia

The intracellular bacterium Wolbachia is a biocontrol tool used to limit the transmission of arboviruses such as dengue virus (DENV) by Aedes aegypti mosquitoes (1-3). While its antiviral properties in Ae. aegypti are well-established, the exact mechanisms by which Wolbachia inhibits viral replication remain unclear. Previous studies have used surrogate systems including Drosophila melanogaster-derived cells, and the alphavirus Sindbis virus to show that Wolbachia’s antiviral effects are confined to Wolbachia-infected cells and do not extend to neighbouring Wolbachia-free cells (4).  Since the antiviral effects of Wolbachia can be host-specific, here we replicate these experiments using biologically-relevant Ae. aegypti-derived cells and DENV. By co-culturing cells with or without Wolbachia in a transwell system, we assessed whether Wolbachia-infected cells can restrict DENV replication in Wolbachia-free cells separated by a porous membrane. Our findings demonstrate that Wolbachia-free cells co-cultured with Wolbachia-infected cells had no reduction in viral replication compared to those co-cultured with other Wolbachia-free cells. This indicates that Ae. aegypti cells infected with Wolbachia do not release factors that can confer antiviral protection to surrounding Wolbachia-free cells and provides further insight into the mechanism of viral restriction by Wolbachia.

  1. 1. O'Neill SL, Ryan PA, Turley AP et al. Scaled deployment of Wolbachia to protect the community from dengue and other Aedes transmitted arboviruses. Gates Open Research. 2019;13;2:36. doi: 10.12688/gatesopenres.12844.3
  2. 2. Utarini A, Indriani C, Ahmad RA, Tantowijoyo W, Arguni E, Ansari MR, et al. Efficacy of Wolbachia-Infected Mosquito Deployments for the Control of Dengue. New England Journal of Medicine. 2021 10;384(23):2177–86. doi: 10.1056/nejmoa2030243
  3. 3. Ryan PA, Turley AP, Wilson G et al. Establishment of wMel Wolbachia in Aedes aegypti mosquitoes and reduction of local dengue transmission in Cairns and surrounding locations in northern Queensland, Australia. Gates Open Res. 2020 8;3:1547. doi: 10.12688/gatesopenres.13061.2
  4. 4. Nainu F, Trenerry A, Johnson KN. Wolbachia-mediated antiviral protection is cell-autonomous. Journal of General Virology. 2019;100(11):1587-1592. doi: 10.1099/jgv.0.001342