Mice were euthanized on days 3, 5, 7, 14, 21, and 32 post-infection, and the 2W-specific CD4+ T cell response was assessed in the SLOs, liver, and blood using flow cytometry following enrichment for Ag-specific CD4+ T cells using 2W:I-Ab tetramer and magnetic bead technology (19) (Figure 1A). This evidence concerns the gene CD4 and infection.