Figure 1. Generation, phenotype, and MCMV infection outcome of BALB mice congenic for the natural killer gene complex inherited from MA/My mice.

(A) Left, physical map of chromosome 6 markers used to determine the size of the MA/My fragment introgressed into the BALB background. The four versions of chromosome 6 indicate the genotypes of sub-congenic strains produced during the generation of BALB.Cmv3^{MA /My} congenic mice carrying a 10 Mb segment (between SNPs rs13479016 and rs13479061) spanning the NKC region from parental MA/My mice. Right, physical map of chromosome 17 markers used to characterize the 9.4 Mb segment (between D17Mit28 and D17Mit51) comprising the H2 region of BALB.K mice (H2^k). (B) NK cell receptor expression in MA/My parental mice and derived BALB-Cmv3^MA/MyH2^d and BALB-Cmv3^MA/MyH2^k congenic mice. The receptors (indicated on the bottom of the panel) were gated by FACS on NKp46⁺ splenic NK cells; the proportion of expression is indicated in each histogram. (C) Viral load in spleens (left) and livers (right) of mice of the indicated genotypes, as determined by plaque-forming assays 3 days p.i. (D) Spleen size (top) and weight and total cellularity (bottom) determined in MA/My and BALB-Cmv3^MA/MyH2^k mice at 7 days p.i. White bar, uninfected mice; black bar, MCMV-infected mice. Data were analyzed using two-way ANOVA analysis and the two-tailed Student's test. Data are presented as mean ± SEM and P values of significant differences between groups are indicated. Results shown in panel B are representative of three experiments using 2–3 mice per group; results shown in panels C and D are representative of five independent experiments using 3–8 mice per group.