Macrophages (CD11b+ Gr1− CD11c− and CD11b+ Gr1− F4/80+ CD11c+), monocytes (CD11b+ Gr1int), and neutrophils (CD11b+ Gr1high) were the predominant leukocyte populations containing parasites at these early time points after infection, with macrophage/monocyte populations clearly dominating by 5 days postinfection. This evidence concerns the gene ITGAX and infection.