DEPLETION OF CD4+ T-CELLS IN MAJOR HISTOCOMPATIBILITY COMPLEX CLASS-II DEFICIENT MICE

The maturation of T cells in the thymus is dependent on the expression of major histocompatibility complex (MHC) molecules. By disruption of the MHC class II A-beta-b gene in embryonic stem cells, mice were generated that lack cell surface expression of class II molecules. These MHC class II-deficient mice were depleted of mature CD4+ T cells and were deficient in cell-mediated immune responses. These results provide genetic evidence that class II molecules are required for the maturation and function of mature CD4+ T cells.