Ricerc@Sapienza

Nematodes of the genus Anisakis are the causative agents of anisakiasis, an emerging fish-borne zoonotic disease, characterized by gastrointestinal, ectopic or allergic reactions, following the ingestion of infected raw or undercooked fishes. Despite its increasing public health awareness, most of the mechanisms of infection and clinical outcomes in humans are still unknown. Establishment of successful long-term infections by pathogens usually involves manipulation of host immune responses. Exosomal microvesicles (carrying proteins, DNA and non-coding RNAs) recently emerged as relevant players in intercellular signalling and parasite-host interactions. To identify molecules putatively involved in penetration of host tissues, we recently completed Anisakis larval and pharyngeal transcriptome analyses. To obtain a deeper understanding of molecules involved in host manipulation, we propose to characterize the Anisakis exosomal miRNAs content. MiRNAs play crucial roles in post-transcriptional regulation and pathogens also exploit them to target host genes. Within exosomes, miRNAs travel in a protected state and, as reported for the nematode Brugia malayi, they may actively target host responses to infection. So far, nothing is known on Anisakis exosomal miRNAs and their role in host-parasite interaction. Using RNAseq and cutting-edge bioinformatics, we propose here the characterization of miRNAs from Anisakis larvae and their released exosomes. This is expected to provide the first Anisakis miRNA catalogue, allowing comparative analyses with other nematodes and the identification of potentially targeted human genes. The establishment of a reliable exosome purification protocol will also pave the way for proteomic and electron microscopy studies. Finally, our analysis may shed some light on mechanisms of host manipulation by anisakid nematodes and may help the development of early diagnostic biomarkers, as well as allergen-specific, preventive and therapeutic targets.