As previously observed [17, 22], analysis of thymic differentiation of DN, DP and SPs thymocytes regarding CD4 and CD8 markers during the acute infection, showed a huge decrease in the percentages (Figure 2B and 2C) and total numbers (Figure 2D) of DP thymocytes, starting at 13 d.p.i. and partially recovering later in infection. This evidence concerns the gene CD8A and infection.