Close phenotypic and functional similarities between human and murine alphabeta T cells expressing invariant TCR alpha-chains.
Several studies have demonstrated the existence of a murine NK1.1+ alphabeta T cell subset expressing V alpha14+ TCR alpha-chains with highly conserved invariant junctional sequences and able to secrete Th2 cytokines when exposed to CD1+ stimulator cells. In humans, alphabeta T cells carrying invariant V alpha24+ TCR alpha-chains highly homologous to those expressed by murine NK1.1 cells have been recently described. Here we show that these cells (referred to as V alpha24inv T cells) and murine NK1.1+ alphabeta T cells resemble each other in several ways. First, like their murine counterparts, T cells expressing high levels of V alpha24inv TCRs can be either CD4- CD8- double negative (DN) or CD4+, but they never express heterodimeric CD8 molecules. Second, most V alpha24inv T cells are brightly stained by NKRP1-specific mAb but not by mAb directed against other type II transmembrane proteins of the NK complex. Third, DN and particularly CD4+ V alpha24inv T cells are greatly enriched for IL-4 producers. The concomitant expression of highly conserved TCRs of a particular set of NK markers and of Th2 cytokines in human and murine alphabeta T cells suggests a coordinate acquisition of these phenotypic and functional properties. Furthermore, the relatively high frequency of human V alpha24inv T cells, which are presently shown to represent on average 1/500 PBL, and the high interindividual variations of the size of this cell subset under physiologic conditions go for a major role played by alphabeta T cells carrying invariant TCR in a large array of immune responses.
Davodeau
F
F
INSERM U211, Institute of Biology, Nantes, France.
Peyrat
M A
MA
Necker
A
A
Dominici
R
R
Blanchard
F
F
Leget
C
C
Gaschet
J
J
Costa
P
P
Jacques
Y
Y
Godard
A
A
Vie
H
H
Poggi
A
A
Romagné
F
F
Bonneville
M
M
D000818:Animals; D000911:Antibodies, Monoclonal; D015704:CD4 Antigens / Q000032:analysis; D016827:CD8 Antigens / Q000032:analysis; D006801:Humans; D015847:Interleukin-4 / Q000096:biosynthesis; D007694:Killer Cells, Natural / Q000276:immunology*; D051379:Mice; D010641:Phenotype; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000032:analysis*
D000911:Antibodies, Monoclonal; D015704:CD4 Antigens; D016827:CD8 Antigens; D016693:Receptors, Antigen, T-Cell, alpha-beta; D015847:Interleukin-4