Cytokine and chemokine expression in infected mice. Cytokine and chemokine mRNA expression was examined in sorted microglia (black) and macrophages (blue) from rJHMV-infected brains of WT, Lyz-DP1−/−, CX3CR1-DP1−/−, and DP1−/− mice at 3 dpi. Gene expression was normalized to HPRT. Pooled data from three independent experiments with 10 to 12 mice per group were analyzed by a Mann-Whitney U test (means ± SEM). *, P < 0.05; **, P < 0.01; ***, P < 0.001; ****, P < 0.0001.