FIG. 1.

NKG2D-dependent virus control in vivo. (A) CBA/J, C3H/J, and BALB/c mice were injected i.v. with 3 × 10⁵ PFU of WT MCMV (MW97.01). C57BL/6 mice received the same dose of Δm157 MCMV. Mice were injected i.p. with PBS or with blocking anti-NKG2D MAbs. Virus titers were determined 3 days p.i. There were significant differences in virus titers in spleen between the groups of untreated mice and groups treated with anti-NKG2D MAbs: for CBA/J mice (P = 0.008) and for C57BL/6 mice (P = 0.038). Because of small number of animals per group (n = 3) for C3H/J mice, although the virus titer differences are indicative, there were no statistically significant differences. (B) C57BL/6 mice, injected i.p. with either PBS or blocking NKG2D MAbs either alone or in combination with cytolytic anti-CD4 and anti-CD8 MAbs, were injected i.v. with 2 × 10⁵ PFU of Δm157 virus. Virus titers were determined 7 days p.i. There were significant differences between the untreated group and the T-cell-depleted group (P = 0.029), as well as between the untreated group and the group treated with anti-NKG2D, anti-CD4, and anti-CD8 MAbs (P = 0.049). (C) DBA/2 mice were injected i.p. with PBS or blocking NKG2D MAbs or, in addition, with cytolytic anti-CD4 and anti-CD8 MAbs. The mice were also injected i.p. with 5 × 10⁴ PFU of SGV-WT MCMV. Virus titers were determined 11 days p.i. There were significant differences between the untreated group and the T-cell-depleted group (P = 0.049), as well as the untreated group and the group treated with anti-NKG2D, anti-CD4, and anti-CD8 MAbs (P = 0.029). Titers for individual mice (circles) and median values (horizontal bars) are shown.