Differential oncolytic effect of NK-enriched subsets in long-term interleukin-2 cultures.
The aim of this study was to characterize the oncolytic efficacy of human natural killer (NK) cell subsets generated from highly NK-enriched population in long-term IL-2 cultures. NK cells cultured for 3 weeks with interleukin-2 (IL-2) were separated into several subsets using two color fluorescence-activated cell sorting and CD2, CD8, CD16, and CD56 monoclonal antibodies. These individual NK cell subsets were then tested for cytotoxicity against various tumor target cell lines, including K-562, Daudi, and Ovcar-3. The CD16+/CD56+ NK cell subset was superior in its cytotoxic activity against all targets in comparison to the CD16-/CD56+ subset. Within CD16 population, CD16+CD2+ NK cells were most potent; however CD16+/CD2- subset was also cytotoxic, indicating that CD2 molecule is important, but not necessary for NK cell cytotoxic function. CD16+/CD8+ and CD16+/CD8- subsets showed variance in cytolytic efficacy, depending on the tumor target tested. Highest cytotoxicity against K-562 was observed in the CD16+/CD8+ population, while the CD16+/CD8- subset manifested highest cytotoxic activity against Daudi. No significant differences within these NK cell subsets were observed against Ovcar-3 targets. These data indicate that NK cell subsets are not equally oncolytic, and that the oncolytic effect may be tumor dependent.
D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D018801:CD2 Antigens; D019002:CD56 Antigen; D016827:CD8 Antigens; D002460:Cell Line; D003602:Cytotoxicity, Immunologic / Q000187:drug effects; D006801:Humans; D016130:Immunophenotyping; D007376:Interleukin-2 / Q000494:pharmacology*; D007694:Killer Cells, Natural / Q000276:immunology*; D016131:Lymphocyte Subsets / Q000276:immunology*; D017452:Receptors, IgG; D011971:Receptors, Immunologic
D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D018801:CD2 Antigens; D019002:CD56 Antigen; D016827:CD8 Antigens; D007376:Interleukin-2; D017452:Receptors, IgG; D011971:Receptors, Immunologic