Figure 3. Ly49H^lo NK cells produce more IFN-γ during early MCMV infection.

(A-D) Splenic Ly49H^lo and Ly49H^hi NK cells were sorted for RNA-seq at day 1.5 PI (4 replicates each). (A) Heat map and hierarchical clustering of top 100 differentially expressed genes by p-value. (B-C) Gene ontology analysis of differential KEGG pathways for genes significantly (p_adj < 0.05) upregulated in Ly49H^hi NK cells (B) and upregulated in Ly49H^lo NK cells (C). Their respective p values are shown. (D) Quantification of RNA-seq reads mapping to the Ifng locus. P value was calculated in DESeq2 and adjusted for testing multiple hypotheses.

(E) Histograms of intracellular IFN-γ expression in splenic Ly49H⁺ NK cells from UI and MCMV-infected WT mice at day 1.5 PI (left). Quantification of percent IFN-γ⁺ NK cells within indicated NK cell populations (right). Data are representative of at least five independent experiments with 3–15 mice per experiment.

(F) As in (E), except UI or MCMV-infected Ifng-IRES-YFP mice at day 1.5 PI. Histograms (left) and quantification of YFP MFI (right) before and after MCMV infection. Data are representative of two independent experiments with 2–3 mice per time point per experiment.

(G) Kaplan-Meier survival curves of Rag2^−/− Il2rg^−/− mice that received either no cells, 50,000 purified Ly49H^lo NK cells, or 50,000 purified Ly49H^hi NK cells 2 days prior to MCMV infection. Data are pooled from two independent experiments with 4–5 mice per group per experiment.

Groups were compared using a paired, two-tailed t test (E, F) or the Log-rank (Mantel-Cox) test with correction for testing multiple hypotheses (G). Data are presented as the mean ± SEM. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001. See also Figures S2 and S3 and Table S1.