ISG15 and infection: RT-qPCR did not reveal significant differences in the amount of TMEV RNA as well as Ifnb1, Isg15, Eif2ak1 (PKR), Tnfa, Il1a, Il1b, Il6, Il10, Il12 (p40) and Ifng transcript numbers in the brain of Asc−/− and Casp1−/− mice and their respective wild type littermates at 4 days after TMEV infection (Fig. 4).