sensitivity of normal cells to natural killer (NK) cells was studied by the use of mutant mice
made deficient for expression of β2-microglobulin (β2m) through homologous recombination
in embryonal stem cells. T-cell blasts from β2m-deficient (β2m-/-) mice were killed by NK
cells from normal mice in vitro, while β2m+/-blasts were resistant. The β2m defect also
affected the NK effector cell repertoire: NK cells from β2m-/-mice failed to kill β2m-/-blasts …