Human lymphoblast cell lines: antibody-dependent cytotoxicity

Five cell lines were isolated after prolonged culture of human buffy coat leukocytes. The cells consisted for the most part of lymphoblasts morphologically similar to those produced by in vivo or in vitro stimulation of small lymphocytes by antigens or mitogens. One of the lines possessed virus-like particles of the Epstein-Barr type. All the established lines were capable of mediating antibody-dependent cytotoxicity (LADC) quantitatively at a level not significantly different from that mediated by freshly isolated, normal human peripheral blood lymphocytes (PBL). The LADC of the lymphoblasts was inhibited by all the human IgG subclasses tested (IgG1, IgG2, IgG3, IgG4) as was the LADC of PBL. It is concluded that, at least so far, the lymphoblasts have retained the properties of the lymphocytes from which they were originally derived as regards their ability to mediate LADC.