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Updated: Aug 14, 2026

Dextran Enhances the Lentiviral Transduction Efficiency of Murine and Human Primary NK Cells
Published on: January 15, 2018
Inhibitory receptors alter natural killer cell interactions with target cells yet allow simultaneous killing of
M Eriksson1, G Leitz, E Fällman
1Umeå Center for Molecular Pathogenesis (UCMP), Umeå University, S-901 87 Umeå, Sweden. mikael.eriksson@ucmp.umu.se
Inhibitory receptors expressed on natural killer (NK) cells abrogate positive signals upon binding corresponding major histocompatibility complex (MHC) class I molecules on various target cells. By directly micromanipulating the effector-target cell encounter using an optical tweezers system which allowed temporal and spatial control, we demonstrate that Ly49-MHC class I interactions prevent characteristic cellular responses in NK cells upon binding to target cells. Furthermore, using this system, we directly demonstrate that an NK cell already bound to a resistant target cell may simultaneously bind and kill a susceptible target cell. Thus, although Ly49-mediated inhibitory signals can prevent many types of effector responses, they do not globally inhibit cellular function, but rather the inhibitory signal is spatially restricted towards resistant targets.
Inhibitory receptors expressed on natural killer (NK) cells abrogate positive signals upon binding corresponding major histocompatibility complex (MHC) class I molecules on various target cells. By directly micromanipulating the effector-target cell encounter using an optical tweezers system which allowed temporal and spatial control, we demonstrate that Ly49-MHC class I interactions prevent characteristic cellular responses in NK cells upon binding to target cells. Furthermore, using this system, we directly demonstrate that an NK cell already bound to a resistant target cell may simultaneously bind and kill a susceptible target cell. Thus, although Ly49-mediated inhibitory signals can prevent many types of effector responses, they do not globally inhibit cellular function, but rather the inhibitory signal is spatially restricted towards resistant targets.
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