Expression of 129/Ola alleles of Ly49 receptors on LTβR^–/–NK cells. Flow cytometric analysis (A-B) was performed on freshly isolated splenocytes from B6, 129/Ola, and LTβR^–/– mice. (A) DX5-enriched cells were stained with mAbs for DX5, CD3 and with 12A8 and 4E5 mAbs. The regions R1 to R6, which are referred to in the text, are indicated. (B) Splenocytes from 129/Ola mice were stained with mAbs for DX5, CD122, and CD3 and with the indicated antibodies specific for the different Ly49 receptors and CD94/NKG2. The results are presented as the percentage of positive cells in the region indicated by the horizontal bar. Analysis was performed by gating on (A) DX5⁺CD3^– splenocytes or (B) DX5⁺CD122⁺CD3^– splenocytes. (C) RNA was extracted from DX5-enriched splenocytes from the indicated mouse strains, and RT-PCR was performed using primers generated for Ly49 receptor family members ly49u/i (U/I), ly49o (O), and ly49v (V) from 129/J mice. The length of the PCR products obtained with Ly49U/I primers are indicated.