ERVW-1 and AIDS: MVA-B, the attenuated vaccinia virus vector MVA expressing the HIV-1 antigens Env, as monomeric gp120, and Gag, Pol and Nef, as a polyprotein, from clade B, is considered a vaccine candidate against HIV/AIDS [7], based on preclinical studies in different animal models [3], [7] and on gene signatures triggered in human dendritic cells [12].