Given the Th1 bias of T. gondii infection it is of interest to note that expression of these Th2 related chemokines is down-regulated by Th1 associated cytokines such as IFNγ and TNFα [17], [18] and is not detected in Th1 associated infections such as Staphylococcus aureus, Candida albicans, or influenza virus [18]. This evidence concerns the gene IFNG and infection.