Characterization with monoclonal antibodies of human lymphocytes active in natural killing and antibody-dependent cell-mediated cytotoxicity of dengue virus-infected cells.

Non-immune human peripheral blood lymphocytes (PBL) lyse dengue virus-infected cells to a greater degree than uninfected cells. In the present study, the PBL active in lysing dengue virus-infected Raji cells are characterized using monoclonal antibodies and are compared to lymphocytes that lyse K562 cells. Leu11+ cells lyse dengue virus-infected cells and K562 cells. Leu11- cells lyse dengue virus-infected cells, but not K562 cells. In the Leu11+ fraction, Leu11+ Leu7- cells are more active than Leu11+ Leu7+ cells in lysing dengue virus-infected cells. T3+ cells also lyse dengue virus-infected cells, but they do not lyse K562 cells. T3- cells lyse both target cells. These results, along with the observation that Leu11+ cells and T3+ cells are different subsets of PBL, indicate that the PBL that are active in lysing dengue virus-infected cells are heterogeneous and are contained in Leu11+ and T3+ subsets. Leu11+ cells are more active than T3+ cells. Leu11+ cells are active in lysing dengue virus-infected cells by antibody-dependent cell-mediated cytotoxicity, whereas T3+ cells are not active.