The Galleria Mellonella Infection Model

The greater wax moth, G. mellonella has been widely used for screening microbial mutants and for assessing the efficacy of antimicrobial drugs (Kavanagh & Reeves, 2004) but in the wild it is a pest of beehives where larvae tunnel through the honeycombs by chewing the wood of which they are composed. Larvae can also cause severe structural damage to the hive, leaving it unusable and liable to disintegration. Although they have no direct effect on the bees in a hive they leave a silk trail, which often traps bees which eventually die.

Recent studies have shown that larvae of G. mellonella may be used as effective models for studying microbial virulence. We have demonstrated that larvae of the G. mellonella can be employed to determine the relative virulence C. albicans isolates and to differentiate between pathogenic and non-pathogenic yeast species (Cotter et al., 2000). A positive correlation between the virulence of C. albicans mutants when tested in G. mellonella and in BalbC mice has been also established (Brennan et al., 2002) and a number of factors affecting the virulence of C. albicans mutants in Galleria larvae have been identified (Dunphy et al., 2003). G. mellonella larvae were also employed to establish appropriate infection models for Cryptococcus neoformans (Mylonakis et al., 2005). Larvae of G. mellonella have been used to demonstrate a correlation between toxin production and virulence of the pulmonary pathogen Aspergillus fumigatus (Reeves et al., 2004) and a correlation between the stage of A. fumigatus spore germination and virulence has also been established (Renwick et al., 2006). Earlier work has demonstrated the use of Galleria larvae for investigating the immunosuppressive activities of fungal s econdary metabolites (Gotz et al., 1997), by assessing anti-phagocytic properties and changes in cytoskel-etal microtubule formation.

Walters & Ratcliffe (1983) studied the differential pathogenicity of Bacillus cereus and Escherichia coli using larvae of G. mellonella and established that B. cereus is more virulent than E. coli, as is the case in mammalian models, and that B. cereus trapped in nodules within the larval haemolymph were able to overcome the effects of the host's immune system. Larvae of G. mellonella have been used to assess the virulence of Bacillus thuringiensis and B. cereus and strong agreement has been established between the results obtained in insects and mice (Salamitou et al. 2000). A strong correlation between the virulence of Pseudomonas aeruginosa in Galleria larvae and in mice has also been demonstrated (Jander et al., 2000). In an examination of the response of G. mellonella and mice to a P. aeruginosa PA14 rpoN mutant (Hendrickson et al., 2001) it was demonstrated that similar virulence genes were required for infection in insects and mice. G. mellonella larvae were used to study the pathogenicity of the entomopathogenic bacterium, Xenorhabdus nemat-ophila, and the effects of its metabolic secretions on the viability of G. mellonella larvae (Mahar et al., 2005). In this case, rather than investigating the pathogenicity of the bacteria, this study was concerned with the management of the G. mellonella beehive infestation. G. mellonella is an appropriate non-mammalian host for studying the role of the type III secretion system in Pseudomonas aeruginosa (Miyata et al., 2003). Bouillaut et al. (2005) employed G. mellonella larvae to investigate virulence factors of B. cereus and B. thuringiensis, controlled by the PlcR transcriptional regulator and determined that inactivation of plcR decreased but did not abolish bacterial virulence.

Cure Your Yeast Infection For Good

Cure Your Yeast Infection For Good

The term vaginitis is one that is applied to any inflammation or infection of the vagina, and there are many different conditions that are categorized together under this ‘broad’ heading, including bacterial vaginosis, trichomoniasis and non-infectious vaginitis.

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