IFN-tau: a new type IIFN with antiretroviral activity.

Type I interferon (IFN) such as IFN-alpha have demonstrated relative effici ency in HIV-infected patients with Kaposi's sarcoma. Nevertheless, their cl inical uses have been restricted by several major side effects. IFN-tau is a non-cytotoxic type I IFN, In the present manuscript, we described its in vitro effects towards HIV replication and its mode of action. IFN-tau is a potent antiviral molecule that interferes with an early step of HIV biologi cal cycle. Moreover, it induces IL-6 synthesis by macrophages, and this cyt okine favorises its antiviral efficacy, probably by amplifying the inductio n of 2', 5'OAS and RNase L. Altogether, these results confirm the interest of IFN-tau as adjuvant therapy in HIV infection, and more particularly in H IV/HCV-infected patients.