Inhibitory role of murine Ly49 lectin-like receptors on natural killer cells.

Abstract

Natural killer (NK) cells are an essential component of the innate immune system, both as cytotoxic effectors and as a source of cytokines that modulate the activity of other cells, including T cells and macrophages. While the molecular mechanisms involved in NK cell activation are not completely understood, significant progress has been made in the characterization of the inhibition of NK cell-mediated lysis. It has become clear that the interaction between target cell MHC class I molecules and specific MHC class I-binding inhibitory receptors on NK cells interrupts the process of NK cell activation (Yokoyama 1998a; Lanier 1998). The physiological significance of this type of recognition finds its best explanation in the “missing self” hypothesis (Ljunggren and Kärre 1990), which suggests that NK cells recognize and kill cells that have lost normal expression of MHC class I molecules, e.g. during viral infections or malignant processes.KeywordsNatural Killer CellMajor Histocompatibility Complex ClassNatural Killer Cell ReceptorClassical Major Histocompatibility Complex ClassLy49 ReceptorThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.