IL18 and fatty liver disease: Obese C57BL/6 mice (naturally harboring the NLRP1b2 allele-resulting in low IL-18 levels) have increased hepatic steatosis when compared to obese NLRP1b1 transgenic C57BL/6 mice or Balb/c mice (naturally harboring the NLRP1b1 allele-resulting in high IL-18 levels) (67).