Wolbachia infection dynamics in Aedes albopictus and the generation and cultivation of cell cultures infected with Wolbachia derived from filarial nematodes.

摘要

Wolbachia is a vertically inherited endosymbiotic bacteria found in many invertebrates. In insects, the presence of a Wolbachia infection can result in reproductive aberrations including cytoplasmic incompatibility. Cytoplasmic incompatibility between infected males and uninfected females can reduce brood hatch and has been proposed as a means of controlling insect populations. In filarial nematodes, Wolbachia infections have been identified as mutualists necessary for successful reproduction, and as such, are novel targets for antifilarial compounds.; Here I have characterized the effect of environmental and host factors on cytoplasmic incompatibility levels in Aedes albopictus. In addition to being a medically important pest and disease vector, A. albopictus is also known to harbor multiple Wolbachia infections, making this mosquito ideal for investigating Wolbachia infection dynamics and control strategies. Food-stress, repeated male matings, male age, and egg age were not observed to affect cytoplasmic incompatibility levels, which remained high with almost no egg hatch occurring.; Differing rates of Wolbachia invasion are predicted for the different population replacement events that can occur in A. albopictus. However, similar replacement rates were observed in population cage tests. As a possible explanation for this discrepancy, fitness of immatures was examined. No difference was observed in immature survivorship, but Wolbachia infections were observed to accelerate developmental rates in A. albopictus.; Efforts to develop a protocol for maintaining stable, closed laboratory cages of A. albopictus are also discussed along with an initial comparison of superinfected and uninfected populations. Population cages will serve as a model system to examine Wolbachia infection dynamics, host population dynamics and their interaction. This information will aid in the design and testing of safe and effective control strategies. Efforts to create novel drug therapies for filariasis targeting their Wolbachia symbionts will benefit from the generation of a stable infection of Wolbachia derived from the filarial nematodes Brugia malayi, and Dirofilaria immitis. Both infections were successfully introduced into an A. albopictus cell line and may be cryogenically stored or stably maintained. It is hoped that these cell lines will serve as a medium for the rapid screening of antimicrobials that target Wolbachia.