A significant increase in serum IL-10 between WT and IL-4 animals−/− (p > 0.05) was not observed, although both had higher systemic levels after infection (NI WT vs. Inf WT, p = 0.002, t = 4.25 and NI IL-4−/− vs. Inf IL-4−/−, p = 0.001, t = 4.89) (Figure 3). This evidence concerns the gene IL4 and infection.