Phenotype of rat natural killer cells defined by monoclonal antibodies marking rat lymphocyte subsets

The fluorescence-activated cell sorter and a rosette-depletion technique were used to separate rat spleen lymphocytes and BCG-activated lymphocytes into subpopulations with and without the antigens defined by W3/13, W3/23 and OX8 monoclonal antibodies. The resultant populations were then tested for natural killer (NK) activity in a quantifiable 6 hr 51Cr release assay. The data establish that rat natural killer cells are heterogeneous with respect to their surface antigen expression and that subpopulations of rat NK cells express the OX8 and W3/13 defined antigens. However, rat NK cells do not express the antigen defined by W3/24 monoclonal antibody.