Although a similar mechanism may contribute to mortality in 129 mice, we found increased mortality of 129 compared with B6 mice also on a Rag-deficient background, and we did not find differences between B6, 129 and IFNαβR−/−(129) mice in the numbers or activation phenotype of influenza-specific CD8 T cells as identified by MHC class I tetramer staining. Here, CD8A is linked to influenza.