Normal Development of Mice Deficient in β2M, MHC Class I Proteins, and CD8+ T Cells (Reprinted from Science, vol 248, pg 1227-1230, 1990)

Major histocompatibility class I proteins display viral and self antigens to potentially responsive cells and are important for the maturation of T cells; beta(2)-microglobulin (beta M-2) is required for their normal expression. Mouse chimeras derived from embryonic stem cells with a disrupted beta M-2 gene transmitted the inactivated gene to their progeny. Animals homozygous for the mutated beta M-2 gene were obtained at expected frequencies after further breeding. The homozygotes appeared normal, although no class I antigens could be detected on their cells and the animals are grossly deficient in CD4(-)CD8(+) T cells, which normally mediate cytotoxic T cell function.