Clone 5.133 reacts with CD158e (KIR3DL1) and CD158k (KIR3DL2), members of the killer immunoglobulin-like receptor (KIR) family which recognizes subsets of HLA alleles. The family of killer immunoglobulin-like receptors (KIR) contributes to the regulation of NK cell-mediated cytotoxicity. Expression is found mainly on CD56dimCD16+ natural killer (NK) cells but also on a subset of CD8+ T cells. They are monomeric receptors possessing high allelic polymorphism with either 2 or 3 Ig-like extracellular domains. According to the length of their cytoplasmic tail, KIRs can be subdivided in inhibitory KIRs and activating KIRs.
Human peripheral blood mononuclear cells (PBMCs) were stained with CD158e/k (KIR3DL1/DL2) antibodies as well as with CD56 antibodies and analyzed by flow cytometry using the MACSQuant® Analyzer. The Tandem Signal Enhancer has been used to increase binding specificity of tandem-dye–conjugated antibodies. Cell debris and dead cells were excluded from the analysis based on scatter signals and propidium iodide fluorescence or 4',6-diamidino-2-phenylindole (DAPI) fluorescence, as in the case of tandems.