Figure 4.

NK function of ES-derived splenocytes from chimeric mice. (A) Generation of NK cells from NKDT and control chimeric mice. ES-derived H-2^b-positive splenocytes were isolated by flow cytometry and cultured for 5 days in the presence of 1,000 units/ml IL-2. Cultured cells were stained with anti-NK1.1 mAb and anti-H-2K^b mAbs, and the expressions of NK1.1 and H-2K^b are shown. (B) NK activity of cultured splenocytes from chimeric mice. H-2K^b-positive splenocytes cultured as described above from NKDT chimeric (■), control chimeric (□), normal (●), and NK1.1⁺ cell-depleted (○) splenocytes. Graded numbers of these effector cells were mixed with YAC-1 target cells at the indicated effector-to-target cell ratios, and cytotoxicity was measured as described in Materials and Methods. Data are presented as the means ± SD from experiments performed in triplicate. (C) The proliferative response of FACS-analyzed T cells from chimeric mice. H-2^b+ and H-2^d+ cells from lymph nodes of both control and NKDT chimeric mice were stimulated with immobilized anti-TCRβ mAb (black bars) or not (open bars); [³H]thymidine was pulsed, and the incorporated [³H]thymidine was measured. Data are presented as means ± SD from experiments performed in triplicate. NK function was analyzed in six individual NKDT mice. Data represent analyses of mice with high chimerism.