Lassa virus (LASV) is responsible for a viral haemorrhagic fever in humans and the death of 3,000 to 5,000 people every year。 There is currently no vaccine or treatmentavailable against LASV, and its pathogenesis is not completely understood yet。 According to studies on humans and primates, type I interferon (IFN-I) and T cell responses appear to be critical for the host。 We studied the response of dendritic cells (DC) to LASV, as DC are involved in both IFN-I production and T cell activation。 We compared the response of primary human DC to LASV and Mopeia virus (MOPV), which is similar to LASV, but non-pathogenic。We focused on plasmacytoid DC (pDC), specialized in IFN-I production, and myeloid DC (mDC), specialized in antigen presentation。 We showed that neither pDC nor mDC were productively infected by LASV and MOPV。 pDC infected with MOPV produced large amounts of IFN-I, whereas pDC infected with LASV did not。 mDC produced substantial amounts of IFN-I in response to both LASV and MOPV。 However, only MOPV-infected mDC were able to activate T cells。 More
