NKG2-C is a receptor on human natural killer cells that recognizes structures on K562 target cells.
NKG2-C is a member of the recently discovered NKG2 family of genes and proteins, which are preferentially expressed on human natural killer (NK) cells. These potential NK cell receptors belong to a larger class of type II transmembrane proteins with a C-type lectin domain. We show here that NKG2-C is expressed as a 36-kDa glycoprotein by translation in vitro, recombinant expression and immunoprecipitation from a human NK cell clone. Further, a recombinant soluble NKG2-C-receptor binds specifically to K562 cells, which are target cells for NK cell killing, and to RPMI 8866 cells, which are feeder cells for NK cells; several other hematopoietic cell lines tested do not show any binding. The binding structures on the surface of K562 cells disappear, concomitant with a loss in susceptibility to killing when the cells are induced to differentiate with phorbol ester and Ca2+ ionophore. Our data suggest the presence of specific target molecules for NKG2-C on K562 cells, since overall glycosylation, Lewis X and Lewis Y structures, as well as the mucin-like CD43 molecule, do not change following induction of the cells. We propose that NKG2-C mediates a specific interaction of NK cells and their target cells with functional importance for NK cell killing.
Düchler
M
M
Department of Transplantation Immunology, Vienna International Research Cooperation Center, Austria.
Offterdinger
M
M
Holzmüller
H
H
Lipp
J
J
Chu
C T
CT
Aschauer
B
B
Bach
F H
FH
Hofer
E
E
D000818:Animals; D002118:Calcium / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects; D002460:Cell Line; D003602:Cytotoxicity, Immunologic; D018076:DNA, Complementary / Q000235:genetics; D004285:Dogs; D006031:Glycosylation; D006801:Humans; D015759:Ionomycin / Q000494:pharmacology; D007694:Killer Cells, Natural / Q000276:immunology* / Q000378:metabolism; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000378:metabolism / Q000473:pathology*; D008562:Membrane Glycoproteins / Q000235:genetics / Q000502:physiology*; D008565:Membrane Proteins / Q000378:metabolism*; D055654:NK Cell Lectin-Like Receptor Subfamily C; D009363:Neoplasm Proteins / Q000378:metabolism*; D017924:Nucleopolyhedroviruses / Q000235:genetics; D011971:Receptors, Immunologic / Q000235:genetics / Q000502:physiology*; D055607:Receptors, Natural Killer Cell; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D018411:Spodoptera / Q000166:cytology; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000378:metabolism
D018076:DNA, Complementary; C527054:KLRC1 protein, human; C527059:KLRC2 protein, human; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D055654:NK Cell Lectin-Like Receptor Subfamily C; D009363:Neoplasm Proteins; D011971:Receptors, Immunologic; D055607:Receptors, Natural Killer Cell; D011993:Recombinant Fusion Proteins; D015759:Ionomycin; D013755:Tetradecanoylphorbol Acetate; D002118:Calcium