Figure 3. IRE1α-XBP1 controls infection-induced NK cell proliferation but not survival.

(a) Schematic of assays evaluating infection-driven NK cell proliferation and apoptosis in b-f. Equal numbers of Ly49H⁺ NK cells from WT (CD45.1) and IRE1^NK (CD45.2) donors were labelled with cell proliferation tracing dye CTV, and then co-transferred into recipient Ly49H-deficient mice 1 day before infection with MCMV. (b) Relative percentages of transferred WT and IRE1^NK Ly49H⁺ NK cells in the spleen of recipient Ly49H-deficient mice at specified time points PI. (c) Representative plots (left) and quantifications (right) of flow cytometric analysis showing CTV dilution of transferred WT and IRE1^NK Ly49H⁺ (responsive) and Ly49H⁻ (bystander) NK cells in the spleen at day 4 PI. Flow cytometric analysis of EdU (d) and Annexin V (e) in co-transferred Ly49H⁺ NK cells at day 3.5 PI. EdU was injected intraperitoneally into mice 12 hr before measurement. (f) Representative flow cytometric plots (left) and quantifications (right) of percentage of FLICA⁺ cells in co-transferred Ly49H⁺ NK cells as in d. n = 4 mice/group for all experiments except n = 3 mice/group in c. All error bars represent mean with s.d.. **p<0.01, ***p<0.001, ****p<0.0001, ns = not significant. Data were analyzed by two-way analysis of variance (ANOVA) with the Sidak post-test (b), one-way analysis of variance (ANOVA) with the Tukey post-test (c), or two tailed unpaired Student’s t-test (d-f). Data are representative of 3 (b, c, f) or 2 (d, e) independent experiments.