CXCR4 and infection: The expression of both CCR7 and CXCR4 increased significantly between 1.5 and 9 months post-infection for T cells specific for all three epitopes (p = 0.0002 and p = 0.0137, respectively) (Figure 3A, left and middle panel), while the expression of CXCR3 remained stable between these two timepoints (Figure 3A, right panel).