The upregulation of ISGs (i.e. CXCL9, IRGM1, PSMB9, STAT1 and UBD) in DBA/2 compared to C57BL/6 mice was confirmed by RT-qPCR at all days post-infection (Figure 7 and Additional file 1: Figure S3). This evidence concerns the gene CXCL9 and infection.