SYTO11 staining vs FISH staining: a comparison of two methods to stain Wolbachia pipientis in cell cultures.

ABSTRACT

AIMS: The Aedes albopictus C7-10 cell line was infected with Wolbachia strains wRi and wAlbB to create C7-10R and C7-10B cell lines, respectively. We compared two different methods, fluorescence in situ hybridization staining and SYTO11 staining, to describe these new Wolbachia infections in C7-10. METHODS AND RESULTS: Both staining methods were as efficient to stain Wolbachia. A formula was developed to quantify Wolbachia infection. The infection levels in C7-10B and C7-10R differed. The live stain SYTO11 was found to be useful to visualize Wolbachia in replicating host cells. Its potential cytotoxic effect at high concentration was investigated. CONCLUSIONS: C7-10 supported two Wolbachia infections, constituting new tools to study Wolbachia-host interactions. The different infection levels suggest that wRi and wAlbB have different requirements for their survival in C7-10 host cell line. Observation of SYTO11-stained live cells gave new insights on Wolbachia segregation pattern during host cell mitosis. SIGNIFICANCE AND IMPACT OF THE STUDY Wolbachia-induced phenotypes in their arthropod and worm hosts could potentially be used to control pest populations. However, the mechanisms underlying these phenotypes are difficult to study because of Wolbachia's intracellular lifestyle. The Wolbachia infections in C7-10 described here could be used as in vitro models to investigate Wolbachia biology.