Examination of the spleen population of CD11c+ (dendritic cells, DC), F4/80+ (macrophage, MΦ), DX5+/CD3− (natural killer, NK) cells and Ly6G+ (polymorphonuclear, PMN) in C5.507 Vi+ or SGB1 (Vi−) infected mice revealed differences in immune cell populations during early infection that correlated with the presence of a functional Vi locus (Figure 6A and Table 1). The gene discussed is ITGAX; the disease is infection.