According to the loss in CD4+ T-cells during primary SIV/HIV-1 infection [29], [30] and the infiltration of cytotoxic CD8+ T-cells within the GC of various lymphoid organs in chronically infected individuals [12]–[14], we stained sections from spleen (data not shown) and MLN on D28 p.i. (Figure 5) for CD3, CD4, CD8 and CD45RO. Here, CD4 is linked to HIV-1 infection.