Relationship between Target Cell Cycle and Susceptibility to Natural Killer Lysis

Studies from several laboratories have evaluated the role of cell surface antigenic molecules on target cells in natural killer (NK)-mediated cytotoxicity. A number of these cell surface molecules are associated with cell proliferation and may be expressed preferentially during one phase of the cell cycle. The purpose of this investigation was to evaluate the role that target cell cycle plays in susceptibility to NK lysis. Enrichment (>80%) of cells from NK-resistant and NK-sensitive cell lines in the G₀G₁S, and G₂M phases of the cell cycle was achieved by centrifugal elutriation. We demonstrate that there was no influence of cell cycle on NK-mediated lysis of NK-resistant or susceptible cell lines.