FIG. 4.

The impact of the inhibition of NKG2D on CD8 T-cell killing in the presence and absence of m152. (A) Representative ⁵¹Cr release assay in the presence of 50 μg/ml of anti-NKG2D. (B) CTL lysis in the presence of anti-NKG2D (open bars) or control IgG (solid bars). +m152 and −m152 indicate the expression of m152 in the viruses used in each group. At least three ⁵¹Cr assays were completed for each epitope, and the results normalized by expressing the lysis of each data point as a percentage of the lysis of Δm4 m6 m152 with control IgG. The means ± standard errors of the means of the normalized results from at least three assays per group using an E/T ratio that was off the maximal plateau are shown. A significant difference (P < 0.05) between lysis in the presence and absence of NKG2D blockade is indicated by an asterisk. (C) Direct comparison of the impacts of m152/gp40 and NKG2D blockade on cytolysis by M97-specific T cells. The data shown in panel B are regraphed to compare virus pairs that differ only by the absence or presence of m152 with and without NKG2D blockade. Error bars show the means ± standard errors of the means. (D) Comparison of the effects of m152/gp40 or m06/gp48 alone in the presence of anti-NKG2D. The data shown in panel B are regraphed to compare the impacts of m152/gp40 and m06/gp48 when NKG2D inhibition is playing no role. Error bars show the means ± standard errors of the means.