The course of TMEV-induced demyelinating disease development, viral persistence levels and CNS-infiltrating mononuclear cells in TMEV-infected in B6 and IL-1R KO mice. (A) Frequency and severity of demyelinating disease in B6 (n = 10) and IL-1R knockout (KO) (n = 10) mice were monitored for 70 days after Theiler’s murine encephalitis virus (TMEV) infection. (B) Viral persistence levels in the pooled brains (BR) and spinal cords (SC) of infected mice (three mice per group) at 8, 21 and 70 days post-infection (dpi) were determined by quantitative PCR. Data are expressed by fold induction after normalization to the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA levels. The values are expressed as the means ± SD of triplicate experiments. Statistically significant differences are indicated with asterisks;*P < 0.05, **P < 0.01, ***P < 0.001. (C) Levels of T cells (CD4+ and CD8+), macrophages (CD11b+CD45high), microglia (CD11b+CD45int), NK cells (NK1.1+CD45+) and granulocytes (Ly6G/6C+CD45+) were assessed using flow cytometry in central nervous system (CNS)-infiltrating mononuclear cells from TMEV-infected C57BL/6 and IL-1R KO mice at 3 and 8 dpi. Numbers in FACS plots represent percentages in the CNS. Data are representative of three experiments using three mice per group.