A mature myeloid antigen identified on human natural killer cells

A rat monoclonal antibody (MAb), NIMP-R10, selected for binding to mouse granulocytes was found to identify all mature human peripheral blood neutrophils and a subpopulation of mononuclear cells. By cell sorting experiments the mononuclear cells labelled with NIMP-R10 were shown to be predominantly large granular lymphocytes encompassing most of the natural killer cell activity of peripheral blood cells. NIMP-R10 blocks the complement receptor on mouse myeloid cells, but the MAb was found to have no such biological activity when human cells were examined.