Exploring transcriptome and microbiome dynamics in response to microbial challenges and nutritional immunomodulation in Hermetia illucens larvae.

Our food system struggles to sustainably meet the demands of the growing world population and needs to shift towards a sustainable, bio-based model. Specific insects are envisioned as actors in this transition, by efficiently transforming renewable biomass into high-quality protein and other compounds. The Black Soldier Fly (BSF) is important for bioconversion, as its larvae are able to valorize low quality organic waste streams (e.g. muncipal bio waste). Such waste streams often have a high microbial load, raising questions on microbial safety.
We will explore to what extent two food pathogens that can contaminate the substrate can colonize the BSF microbiome and if and how modulation of BSF immunity can impact colonization. Larvae will be reared on five substrates, selected to induce distinct immune responses, with or without a bacterial challenge and sampled to determine the pathogen load, the microbiome composition and the host transcriptome. This will allow to gain fundamental insights into the interplay between the pathogen, the microbiome and BSF immunity, as well as on how immune modulation impacts this interplay. The project lays the foundation for more applied post-project research. The identification and characterization of (i) dominant gut bacteria that can lead to the development probiotics for industrial rearing of larvae and (ii) BSF immunity genes that are activated upon pathogen introduction and that can lead to the development of new antimicrobials