IL33 and infection: Because these IFNγ-induced chemokines are known to exert their biological activity via interaction with CXCR3 on TH1 CD4+ T cells and CD8+ effector T cells, the expression of CXCR3 was measured which showed a global decrease during L2-MHV3 infection in WT and IL-33 KO mice (Figure 7(j)), in correlation with T lymphocyte depletion as observed previously (Figure 4(d)).