Accessory cells, dendritic cells, or monocytes, are required for the lymphokine-activated killer cell induction from resting T cell but not from natural killer cell precursors.
In this study we have investigated the role of accessory cells in the development of lymphokine-activated killer cells (LAK) from highly purified human NK and small resting T cell progenitors. As accessory cells we used autologous, as well as allogeneic, monocytes, and dendritic cell enriched cells. Both NK and T cells were able to generate LAK activity, but their activation requirements were different. NK cells were activated merely by IL-2, and accessory cells did not enhance their lytic activity in the presence or absence of IL-2. Conversely, T cells were practically unresponsive to even high concentrations of IL-2 having a strict requirement for accessory cells for the development of lytic activity and proliferation. Accessory cells differed in their ability to activate T cells presumably depending on their ability to induce IL-2 synthesis, allogeneic dendritic cells being the most effective accessory cells and IL-2 synthesis stimulators. Allogeneic accessory cells could induce lytic activity in T cells even in the absence of exogenous IL-2. Thus, accessory cells play a central role in expanding the LAK effector cell population.
Silvennoinen
O
O
Department of Bacteriology and Immunology, University of Helsinki, Finland.
Vakkila
J
J
Hurme
M
M
D000938:Antigen-Presenting Cells / Q000276:immunology* / Q000502:physiology; D003713:Dendritic Cells / Q000276:immunology* / Q000502:physiology; D006801:Humans; D007399:Interphase; D007694:Killer Cells, Natural / Q000276:immunology* / Q000502:physiology; D007958:Leukocyte Count; D008213:Lymphocyte Activation; D008222:Lymphokines; D009000:Monocytes / Q000276:immunology* / Q000502:physiology; D013234:Stem Cells / Q000276:immunology / Q000502:physiology; D013601:T-Lymphocytes / Q000276:immunology* / Q000502:physiology
D008222:Lymphokines