The most frequently used models for such immunological studies are inbred mice, like B57BL6 (H-2 b ) or BALB/c (H-2 d ) mice. Therefore, T-cell influenza specific epitopes in inbred mice were studied by many authors. Comprehensive analysis regarding existing influenza A epitopes in mice among avian and human influenza strains was done by Bui et al. [113] . However, not all Tcell epitopes are equally immunogenic. In inbred mice B57BL6 (H-2 b ), peptides from nucleoprotein D b NP 366-374 and from a subunit of viral RNA polymerase D b PA 224-233 are immunodominant, while nucleoprotein epitope K d NP 147-155 is immunodominant in BALB/ c (H-2 d ) mice [84, [114] [115] [116] .