CD81 and infection: Although CD81 likely contributes to infection of T cells, based on the fact that antibodies against CD81 inhibited infection of primary T cells as well as Molt4 and Jurkat cells with native virus [23], [25], CD81 molecule is not the limiting factor of the infection since HCV-resistant PM1 and CEM T cells express CD81 at similar levels to cells prone to this virus (see Fig. 2A).