Education of human natural killer cells by activating killer cell immunoglobulin-like receptors.
Expression of inhibitory killer cell immunoglobulin-like receptors (KIRs) specific for self-major histocompatibility complex (MHC) class I molecules provides an educational signal that generates functional natural killer (NK) cells. However, the effects of activating KIRs specific for self-MHC class I on NK-cell education remain elusive. Here, we provide evidence that the activating receptor KIR2DS1 tunes down the responsiveness of freshly isolated human NK cells to target cell stimulation in donors homozygous for human leukocyte antigen (HLA)-C2, the ligand of KIR2DS1. The tuning was apparent in KIR2DS1(+) NK cells lacking expression of inhibitory KIRs and CD94/NKG2A, as well as in KIR2DS1(+) NK cells coexpressing the inhibitory MHC class I-specific receptors CD94/NKG2A and KIR2DL3, but not KIR2DL1. However, the tuning of responsiveness was restricted to target cell recognition because KIR2DS1(+) NK cells responded well to stimulation with exogenous cytokines. Our results provide the first example of human NK-cell education by an activating KIR and suggest that the education of NK cells via activating KIRs is a mechanism to secure tolerance that complements education via inhibitory KIRs.
Fauriat
Cyril
C
Center for Infectious Medicine, Department of Medicine, Karolinska Institutet, Karolinska University Hospital Huddinge, Stockholm, Sweden.
Ivarsson
Martin A
MA
Ljunggren
Hans-Gustaf
HG
Malmberg
Karl-Johan
KJ
Michaëlsson
Jakob
J
D003602:Cytotoxicity, Immunologic / Q000276:immunology; D005434:Flow Cytometry; D015236:HLA-C Antigens / Q000235:genetics / Q000378:metabolism*; D006720:Homozygote; D006801:Humans; D018664:Interleukin-12 / Q000378:metabolism; D019409:Interleukin-15 / Q000378:metabolism; D007694:Killer Cells, Natural / Q000276:immunology*; D055654:NK Cell Lectin-Like Receptor Subfamily C / Q000235:genetics / Q000378:metabolism*; D051920:NK Cell Lectin-Like Receptor Subfamily D / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D054340:Receptors, KIR / Q000235:genetics / Q000378:metabolism*; D054344:Receptors, KIR2DL3 / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction
D015236:HLA-C Antigens; D019409:Interleukin-15; C515078:KIR2DL3 protein, human; C496212:KIR2DS1 protein, human; D055654:NK Cell Lectin-Like Receptor Subfamily C; D051920:NK Cell Lectin-Like Receptor Subfamily D; D012333:RNA, Messenger; D054340:Receptors, KIR; D054344:Receptors, KIR2DL3; D018664:Interleukin-12