Pre-NKP–derived NK cells have mature functional phenotype. (A) Pre-NKP–derived splenic NK cells express diverse combinations of Ly49 receptors. Wild-type NK cells and donor NKp46⁺ cells from pre-NKP transplanted Rag2^−/−IL2rγc^−/− mice were stained with a panel of anti-Ly49 family antibodies. Data represents 1 of 2 experiments. (B) Pre-NKP–derived NK cells degranulate on activation. Wild-type NK cells and NKp46⁺ cells derived in vivo from pre-NKP were isolated and stimulated with plate bound anti-NK1.1 for 4 hours in the presence of lysosomal-associated membrane protein 1 (Lamp-1) antibody. Data are representative of 2 independent experiments.