The Mechanism of Leukoregulin Enhancement of Target Cell Susceptibility to NK Cell Mediated Cytotoxicity in Humans
Leukoregulin is an anticancer immunologic hormone or lymphokine whose actions include the inhibition of tumor cell growth and lysis of tumor cells either directly or indirectly by stimulating target cell sensitivity to lysis mediated by natural killer (NK) cells (1, 2, 3). Only a few cell types are directly lysed by leukoregulin and lysis requires very large leukoregulin concentrations. Leukoregulin enhancement of target sensitivity to NK cell cytolysis, however, occurs in the presence of small concentrations of leukoregulin for carcinoma, sarcoma, and leukemia tumor cells (4). Therefore, the primary in vivo means of tumor destruction may be through the combined action of leukoregulin and NK cells.
KeywordsNatural Killer Natural Killer Cell K562 Cell Transferrin Receptor Natural Killer Cytotoxicity
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