IFITMs from Naturally Infected Animal Species Exhibit Distinct Restriction Capacities against Toscana and Rift Valley Fever Viruses

Rift Valley Fever virus (RVFV) and Toscana virus (TOSV) are two pathogenic arthropod-borne viruses responsible for zoonotic infections in both humans and animals; as such, they represent a growing threat to public and veterinary health. Interferon-induced transmembrane (IFITM) proteins are broad inhibitors of a large panel of viruses belonging to various families and genera. However, little is known on the interplay between RVFV, TOSV, and the IFITM proteins derived from their naturally infected host species. In this study, we investigated the ability of human, bovine, and camel IFITMs to restrict RVFV and TOSV infection. Our results indicated that TOSV was extremely sensitive to inhibition by all the animal IFITMs tested, while RVFV was inhibited by human IFITM-2 and IFITM-3, but not IFITM-1, and exhibited a more heterogeneous resistance phenotype towards the individual bovine and camel IFITMs tested. Overall, our findings shed some light on the complex and differential interplay between two zoonotic viruses and IFITMs from their naturally infected animal species.

Automated summary

Rift Valley Fever virus (RVFV) and Toscana virus (TOSV) are pathogenic arthropod-borne viruses that pose a growing threat to public and veterinary health. This study found that TOSV is highly sensitive to inhibition by IFITMs from different animal species, while RVFV is inhibited by human IFITM-2 and IFITM-3, but not IFITM-1, and shows varying levels of resistance to bovine and camel IFITMs. These findings provide insights into the interplay between zoonotic viruses and IFITMs.