To test this possibility, SJL×SWR control and CCL2transgenic mice were infected intracranially with mCMV (Smith strain) or TMEV and monitored for disease development. mCMV is a double-stranded DNA β-herpesvirus that normally replicates in the liver and spleen of susceptible strains of mice dur-ing the replicative phase (approximately 14 days) before entering a latent phase. mCMV can infect astrocytes, neurons, endothelial cells, radial glia, ependymal cells, microglia, and cells from the meninges and choroid in the mouse CNS (Tsutsui et al, 1989; Shinmura et al, 1997; van Den Pol et al, 1999) as well as macrophages (Brautigam et al, 1979) .