CD4 and Lassa fever: Interestingly, the increase in CD4+ cells in the livers of GILZ KO mice was associated with a significant increase in the mRNA expression of IL-4 cytokine in both early and late stages of LF development (Fig. S5A, B), and a modest decrease in IFN-γ mRNA expression at the early stage (Fig. S5C), suggesting a predominance of the Th2-type response in the livers of mice lacking GILZ.