Characterization ofWolbachiaHost Cell Range via the In Vitro Establishment of Infections

Abstract

Maternally transmitted bacteria of the genus Wolbachia are obligate, intracellular symbionts that are frequently found in insects and cause a diverse array of reproductive manipulations, including cytoplasmic incompatibility, male killing, parthenogenesis, and feminization. Despite the existence of a broad range of scientific interest, many aspects of Wolbachia research have been limited to laboratories with insect-rearing facilities. The inability to culture these bacteria outside of the invertebrate host has also led to the existing bias of Wolbachia research toward infections that occur in host insects that are easily reared. Here, we demonstrate that Wolbachia infections can be simply established, stably maintained, and cryogenically stored in vitro using standard tissue culture techniques. We have examined Wolbachia host range by introducing different Wolbachia types into a single tissue culture. The results show that an Aedes albopictus (Diptera: Culicidae) cell line can support five different Wolbachia infection types derived from Drosophila simulans (Diptera: Drosophilidae), Culex pipiens (Culicidae), and Cadra cautella (Lepidoptera: Phycitidae). These bacterial types include infection types that have been assigned to two of the major Wolbachia clades. As an additional examination of Wolbachia host cell range, we demonstrated that a Wolbachia strain from D. simulans could be established in host insect cell lines derived from A. albopictus, Spodoptera frugiperda (Lepidoptera: Noctuidae), and Drosophila melanogaster. These results will facilitate the development of a Wolbachia stock center, permitting novel approaches for the study of Wolbachia infections and encouraging Wolbachia research in additional laboratories.

In vitro infection of Wolbachia in insect cell lines

“…Eggs laid within 12 h were collected from Wolbachia-infected E. kuehniella and D. melanogaster. The Wolbachia were inoculated into the cell lines using the shell vial technique according to Dobson et al (2002) with small modifications. Approximately 2 mg of eggs was used for each inoculation.…”

“…Transfer of various Wolbachia strains into uninfected insect cell lines was achieved by the shell vial technique, in which the host cells were infected with Wolbachia via centrifugation (Dobson et al, 2002). Furthermore, Wolbachia has even been successfully maintained in a mammalian cell line (Noda et al, 2002).…”

Cytological properties of an Aedes albopictus mosquito cell line infected with Wolbachia strain wAlbB

“…In arthropods, the association between the host and Wolbachia is considered commensal or somewhat parasitic, while in filarial worms, the relationship is symbiotic. Although taxonomic and molecular analyses have not established criteria for species designations of Wolbachia, in vitro studies suggest that strains of Wolbachia that occur in insects can be readily transferred between insect hosts (Sinkins and Gould 2006) and to insect cell lines representing diverse orders (Dobson et al 2002).…”

Morfología y citoquímica de cultivos celulares de Aedes aegypti (Diptera: Culicidae) y susceptibilidad a Leishmania panamensis (Kinetoplastida: Trypanosomatidae)

“…Desde entonces, diferentes cultivos celulares de mosquitos se han utilizado como sustratos para el aislamiento e identificación de arbovirus. Sin embargo, existe en la actualidad una amplia gama de aplicaciones biotecnológicas (Singh 1972, Sudeep et al 2005, así como también biomédicas, principalmente en investigaciones con algunas bacterias y parásitos (Syafruddin et al 1992, Dobson et al 2002. En esta última línea de acción, es importante resaltar el estudio realizado por Fampa et al (2003), en el cual se muestra la interacción de ciertas especies de tripanosomátidos monoxenos con líneas celulares de A. albopictus, Anopheles gambiae y Lutzomyia longipalpis.…”