IL18R1 and malaria: To address this, we infected control [IL18rflox/flox or basoIL-18R (+)] mice and mice with basophils lacking the IL-18R [IL18rflox/flox × Basoph8 or basoIL-18R (−)] with Plasmodium yoelii yoelii 17XNL, a nonlethal strain of mouse malaria.