<i>In vivo</i> attenuation of MCMVΔm154 in an NK cell-dependent manner.

<p>(A) Groups of 7-weeks-old BALB/c.ByJ female mice were i.p. inoculated with 2×10⁶ PFU of wt MCMV (open circles) or MCMVΔm154 (filled circles). Changes in the percentage of body weight relative to day 0, measured at days 2, 4, 6 and 8 post infection (pi), are shown. (B) Mice infected as indicated in A were sacrificed at days 2, 4 and 8 after infection and viral titers from selective organs determined. The horizontal dashed line marks the limit of detection. (C) Groups of 7-weeks-old BALB/c.ByJ female mice were i.p. inoculated with 2×10⁶ PFU of wt MCMV (open circles) or MCMVΔm154Int (filled circles). Mice were sacrificed at day 4 after infection and viral titers from the indicated organs determined. (D) Depletion of NK cells restores MCMVΔm154 <i>in vivo</i> phenotype. Groups of 5-week-old BALB/c.ByJ female mice were injected i.p. with anti-asialo GM1 antibody or left untreated. Animals were i.p. inoculated with 5×10⁵ PFU of wt MCMV (open circles) or MCMVΔm154 (filled circles), sacrificed at day 4 after infection and viral titers in spleen and liver determined. Values corresponding to differences in median values between animals infected with the same virus, untreated or treated with anti-asialo GM1 antibody, are shown. *p<0.05, **p<0.01, ***p<0.001, ns: non significant. Each symbol represents an individual mouse. Horizontal bars indicate the median values.