LCMV infection has been shown to induce a relatively strong T-helper response (at least in C57BL/6 mice) focused almost entirely upon two epitopes, GP61–80 and NP309–328, both of which are presented by I-Ab. The LCMV 61-80 peptide acts preferentially as an LCMV T helper epitope and this epitope seems to be processed differently (lysosomal-independent pathway) for viral cell-mediated targeting.