IL18 and infection: Although IL-1 and IL-18 synergize with IL-12 to promote NK cell production of IFN-γ (Hunter et al., 1995a; Cai et al., 2000; Kearley et al., 2015), the role of endogenous IL-1 during toxoplasmosis is secondary to those of IL-12 (Hitziger et al., 2005; Hunter et al., 1995a; Melchor et al., 2020), and endogenous IL-18 is not required for parasite control but rather contributes to the immune pathology that can accompany this infection (Cai et al., 2000; Yap et al., 2001; Vossenkämper et al., 2004; Ewald et al., 2014; Gorfu et al., 2014).