Furthermore, approach II revealed genes (interferon induced genes such as interferon inducible GTPase 1 (IIGP1), CXCL9, as well as VEGF-α) which were highly induced after Yersinia infection but which were lower expressed after lethal ΔyopH infection compared to sublethal or lethal pYV+ infection. This evidence concerns the gene CXCL9 and infection.