Mechanisms of Natural Killer Cell-mediated Tumor Cell Cytolysis at a Single Cell Level

The interaction between natural killer cell and tumor target cells at asingle cell level was investigated.The study with a modified single cell cytotoxicassay showed the heterogeneity and requirment of target cell membrane fluidity inthe formation of natural killer cell-tumor target cell conjugates,as well as aninternal disintegration model of natural killer cell-mediated target cell lysis,which may have some relation to the increased lysosome reaction in damagedtargtet cells as revealed by ultrastructural study.From this finding,a“target cellsuicide”model of natural killer cell mediated target cell lysis is proposed.Inaddition to these findings,the interaction of natural emperipolesis lymphocyteswith tumor cells and its relationship to natural killer cell-mediated killing werealso studied and are discussed here.