Overall and although some differences exist between the two genetic background [23,24], those results suggest that Tha virus could exert a repression of the expression of inflammatory related genes such as IFNß, CXCL2 and TNF in the brain of infected mice at the late stage of the infection compared with Th4M while not affecting CCL5 and CXCL10. This evidence concerns the gene CXCL2 and infection.