STAPHYLOCOCCUS-MEDIATED T-CELL ACTIVATION AND SPONTANEOUS NATURAL-KILLER-CELL ACTIVITY IN THE ABSENCE OF MAJOR HISTOCOMPATIBILITY COMPLEX CLASS-II MOLECULES

We used major histocompatibility complex class II antigen-deficient tr ansgenic mice to show that in vitro natural killer cell cytotoxicity a nd T-cell activation by staphylococcal exotoxins (superantigens) are n ot dependent upon the presence of major histocompatibility complex cla ss II molecules. T cells can be activated by exotoxins in the presence of exogenously added interleukin 1 or 2 or in the presence of specifi c antibody without exogenously added cytokines.