wFlu: characterization and evaluation of a native Wolbachia from the mosquito Aedes fluviatilis as a potential vector control agent

PLoS One. 2013;8(3):e59619. doi: 10.1371/journal.pone.0059619. Epub 2013 Mar 26.

Abstract

There is currently considerable interest and practical progress in using the endosymbiotic bacteria Wolbachia as a vector control agent for human vector-borne diseases. Such vector control strategies may require the introduction of multiple, different Wolbachia strains into target vector populations, necessitating the identification and characterization of appropriate endosymbiont variants. Here, we report preliminary characterization of wFlu, a native Wolbachia from the neotropical mosquito Aedes fluviatilis, and evaluate its potential as a vector control agent by confirming its ability to cause cytoplasmic incompatibility, and measuring its effect on three parameters determining host fitness (survival, fecundity and fertility), as well as vector competence (susceptibility) for pathogen infection. Using an aposymbiotic strain of Ae. fluviatilis cured of its native Wolbachia by antibiotic treatment, we show that in its natural host wFlu causes incomplete, but high levels of, unidirectional cytoplasmic incompatibility, has high rates of maternal transmission, and no detectable fitness costs, indicating a high capacity to rapidly spread through host populations. However, wFlu does not inhibit, and even enhances, oocyst infection with the avian malaria parasite Plasmodium gallinaceum. The stage- and sex-specific density of wFlu was relatively low, and with limited tissue distribution, consistent with the lack of virulence and pathogen interference/symbiont-mediated protection observed. Unexpectedly, the density of wFlu was also shown to be specifically-reduced in the ovaries after bloodfeeding Ae. fluviatilis. Overall, our observations indicate that the Wolbachia strain wFlu has the potential to be used as a vector control agent, and suggests that appreciable mutualistic coevolution has occurred between this endosymbiont and its natural host. Future work will be needed to determine whether wFlu has virulent host effects and/or exhibits pathogen interference when artificially-transfected to the novel mosquito hosts that are the vectors of human pathogens.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aedes / cytology
  • Aedes / drug effects
  • Aedes / growth & development
  • Aedes / microbiology*
  • Animals
  • Cytoplasm / microbiology
  • Female
  • Fertility
  • Humans
  • Insect Control / methods*
  • Insect Vectors / cytology
  • Insect Vectors / drug effects
  • Insect Vectors / growth & development
  • Insect Vectors / microbiology*
  • Male
  • Oocysts / microbiology
  • Organ Specificity
  • Pest Control, Biological / methods*
  • Sex Characteristics
  • Tetracycline / pharmacology
  • Wolbachia / drug effects
  • Wolbachia / physiology*

Substances

  • Tetracycline

Grant support

LAB was supported by a Post-doctoral Fellowship from the Fundação de Amparo à Pesquisa de Minas Gerais (FAPEMIG). ECP was supported by a scholarship from FAPEMIG. DSG was supported by CNPq. LAM is a CNPq research fellow. Financial support was provided by FAPEMIG and CNPq. This work was partially supported by CNPq, FAPEMIG, INCT-EM and CPqRR/Fiocruz. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.