Figure 7.

Ly49H signaling is required for the differentiation of functional memory NK cells. NKp46-CreERT2 Tg mice with homozygous Rosa26-YFP alleles were treated with tamoxifen for 5 d and infected or uninfected with WT or Δm157 MCMV on day 0. (A) Phenotype of YFP⁺ NK cells in the spleens of naive uninfected mice, YFP⁺Ly49H⁺KLRG1^high memory NK cells in the spleens of WT MCMV-infected mice, and MCMV-primed YFP⁺Ly49H⁺KLRG1^high NK cells in the spleens of Δm157 MCMV-infected mice on days 25–27 p.i. The percentages of Ly49H⁺KLRG1^high NK cells are shown. (B and C) Degranulation (B) and IFN-γ production (C) of YFP⁺ Ly49H⁺ NK cells from naive uninfected mice, YFP⁺Ly49H⁺KLRG1^high memory NK cells from WT MCMV-infected mice, and MCMV-primed YFP⁺Ly49H⁺KLRG1^high NK cells from Δm157 MCMV-infected mice after culture with IL-12 and IL-18, stimulation with anti-NK1.1 mAb, and co-culture with RMA cells expressing m157. Data are representative of two experiments (n = 3 in each experiment). *, P < 0.05. P-values were calculated by a Student’s t test. Error bars show SEM.