Expanding the use of alternative models to investigate novel aspects of immunity to microbial pathogens

Abstract

In the present issue of Virulence, an article entitled “The maternal transfer of bacteria can mediate trans-generational immune priming in insects”1 describes an elegant study that illustrates the use of the lepidopteran Galleria mellonella to investigate a specific aspect of immunity to microbes. The authors show that exposure of mothers to bacteria results in enhanced immunity in the offspring. Furthermore, they have demonstrated that bacteria ingested by female larvae are found in the eggs, suggesting that enhanced immunity of the offspring is a consequence of direct exposure of the eggs to bacteria. This is a relevant and novel study for several reasons. The authors provide a mechanism for an important aspect of insect immunity, which is that direct transfer of bacterial fragments from the mother to the eggs primes their immune response. But in addition, this study opens the scope on the use of non-conventional models and illustrates how they can be used to investigate aspects of immunity against pathogenic microorganisms.