ITGAX and infection: To address whether the sublethal and lethal infection with pYV+ and ΔyopH affect the cells involved in innate immune responses, the number of macrophages (CD11b+F4/80+), granulocytes (CD11b+Ly6G+) and dendritic cells (CD11b+CD11c+) in the spleen was determined at day 1 p.i. The total number of macrophages was significantly increased one day after the sublethal infection with both pYV+ and ΔyopH compared with mock-infected mice.