A novel recognition motif of human NKT antigen receptor for a glycolipid ligand.
Murine NKT cells can recognize alpha-galactosylceramide (alpha-GalCer) in the context of a class Ib CD1d molecule. Here we show that alpha-GalCer can selectively activate freshly isolated human Valpha24(+)Vbeta11(+) cells, functionally defining the human NKT cells. The naive human NKT cell repertoire consisted of cells expressing an invariant Valpha24JalphaQ chain and a diverse array of beta chains derived from a single Vbeta11 gene segment. Stimulation with alpha-GalCer expanded a polyclonal subset of the human NKT cell repertoire carrying a novel complementarity-determining region (CDR) 3beta consensus motif that may directly interact with the sugar moiety of alpha-GalCer. Our data suggest that certain redundancy is allowed for CDR3beta of NKT antigen receptor to interact with the ligand and provide a first clue to understand the novel protein-carbohydrate interaction mechanisms.
Kawano
T
T
CREST (Core Research for Evolutional Science and Technology) Project and Department of Molecular Immunology, Graduate School of Medicine, Chiba University, Japan.
Tanaka
Y
Y
Shimizu
E
E
Kaneko
Y
Y
Kamata
N
N
Sato
H
H
Osada
H
H
Sekiya
S
S
Nakayama
T
T
Taniguchi
M
M
D000328:Adult; D000818:Animals; D018949:Antigens, CD1 / Q000276:immunology; D055610:Antigens, CD1d; D001665:Binding Sites / Q000276:immunology; D005312:Fetal Blood / Q000166:cytology / Q000276:immunology; D005699:Galactosylceramides / Q000276:immunology* / Q000378:metabolism*; D006801:Humans; D007694:Killer Cells, Natural / Q000276:immunology* / Q000378:metabolism*; D008024:Ligands; D008213:Lymphocyte Activation / Q000276:immunology; D051379:Mice; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000276:immunology* / Q000378:metabolism*; D016176:T-Lymphocyte Subsets / Q000276:immunology
D018949:Antigens, CD1; D055610:Antigens, CD1d; C526877:CD1D protein, human; D005699:Galactosylceramides; D008024:Ligands; D016693:Receptors, Antigen, T-Cell, alpha-beta