Dysbiosis of the Biomphalaria glabrata vector snail microbiota following infection by Schistosoma parasites

The importance of the microbiota in host-parasite interactions has taken a deeper interest recently. Microbiota has to be considered as a third partner playing a central role in these interactions. Biomphalaria glabrata is the vector snail of the trematode Schistosoma mansoni, the agent of human schistosomiasis causing hundreds of thousands of deaths every year. How snail microbiota is affected in such host-parasite interaction following infection remains unstudied. Here, we analyse for the first time how the snail bacterial microbiota is affected or modified by schistosoma infections. We used a massive 16s DNA sequencing approach (MiSeq) to characterize the Biomphalaria bacterial microbiota at the individual level in naive and infected snails. Sympatric and allopatric strains of parasites were used following infections and re-infections to analyse the modification or dysbiosis of snail microbiota populations in different host-parasite co-evolutionary contexts. Concomitantly, using RNAseq data, we investigate the link between bacterial microbiota dysbiosis and snail anti-microbial immune response. These investigations would have a central role in the understanding of snail/schistosome interaction, and would have critical consequences in terms of snail control strategies for fighting schistosomiasis disease in the field.