NK-cell deficiency in Eri1^−/− mice. (A) Frequency and (B) absolute number of spleen T (CD3ϵ⁺NK1.1⁻), B (CD19⁺), NKT (NK1.1⁺CD3ϵ⁺), NK (NK1.1⁺CD3ϵ⁻), and Mac1⁺ (CD11b⁺NK1.1⁻) cells enumerated by flow cytometry (N = 5, ICR/B6 mice). (C) NK1.1⁺CD3ϵ⁻ NK cells in the indicated tissues. Numbers are NK-cell frequency ± SD among total lymphocytes (N = 5, ICR/B6 mice). (D-F) CD45.1⁺ lethally irradiated hosts were reconstituted with a 1:1 mixture of fetal liver cells from WT (CD45.1⁺ CD45.2⁺) and Eri1^−/− (CD45.2⁺) donors and analyzed 8-15 weeks later (N = 3). (D) Frequency of donor- and host-derived cells among BM LSK (Lin⁻c-Kit⁺ Sca-1⁺) cells and spleen CD45⁺, B, CD4⁺ and CD8⁺ T, NKT, NK, macrophage (CD11b⁺NK1.1⁻Gr1⁻), and granulocyte (CD11b⁺ Gr1⁺) cells. (E) Frequency of donor- and host-derived cells among NK cells in the indicated tissues. (F) Frequency of developing NK-cell subsets (see supplemental Figure 2A for gating strategy) among BM WT (CD45.1⁺CD45.2⁺) and Eri1^−/− (CD45.1⁻CD45.2⁺) cells. Bar graphs show mean ± SD; *P ≤ .05, (A-B) unpaired or (D-F) paired Student t test. All data are representative of at least 2 independent experiments.