FIG 2.

L10 disseminates more efficiently in the mouse brain following i.p. inoculation than SFV4. Representative autoradiographic images illustrating the distribution of virus RNA-positive cells (black) in parasagittal sections of the brains of 4- to 5-week-old BALB/c mice 72 h after i.p. inoculation with SFV4 (A) or L10 (B). In situ hybridization using 35S-labeled riboprobe complementary to the viral genomic RNA. For each of six mice sampled at each time point, three sections from each of three areas of the brain were studied; the images shown are representative of each group of mice. All brains are in the same orientation; the main olfactory bulb (mob) and the cerebellum (cb) demonstrate the rostro-caudal orientation. Following i.p. inoculation, no virus-positive cells were observed in mice inoculated with SFV4. In contrast, in mice inoculated with L10, virus-positive cells were identified throughout the brain.