Expression of the identical V beta gene in human T-cell clones does not confer the same pattern of responsiveness to bacterial enterotoxins.
Superantigens are the most potent T-cell mitogens so far described, and are believed to activate virtually all the T lymphocytes bearing the appropriate V beta segment in their T-cell receptor (TcR). In order to determine whether the expression of the identical V beta gene confers the same pattern of responsiveness to bacterial superantigens, we have established a panel of 20 untransformed human T-cell clones expressing the V beta 6.7a gene in their TcR. The V beta usage was defined by immunostaining, using the V beta 6.7a-specific monoclonal antibody (mAb) OT145, and confirmed by DNA sequencing of the beta-chain. Although all the clones analysed expressed the same V beta gene, they had disparate patterns of proliferation to challenge with a panel of bacterial enterotoxins. This study demonstrates that the mere expression of the same V beta region by T lymphocytes does not grant an indistinguishable responsiveness to bacterial superantigens. Thus other, as yet undefined, T-lymphocyte components play a key role in the process of T-cell activation induced by bacterial superantigens, influencing the effects mediated by exogenous superantigens on human T cells.
Kennedy Institute of Rheumatology, Sunley Division, London, U.K.
S
S
Quaratino
A
A
Verhoef
M
M
Kahan
M
M
Londei
D000595:Amino Acid Sequence; D001483:Base Sequence; D002455:Cell Division / Q000276:immunology; D002999:Clone Cells / Q000276:immunology; D004247:DNA / Q000737:chemistry; D004306:Dose-Response Relationship, Immunologic; D004768:Enterotoxins / Q000276:immunology*; D015870:Gene Expression / Q000276:immunology*; D006801:Humans; D008213:Lymphocyte Activation / Q000235:genetics; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000737:chemistry / Q000235:genetics*; D013601:T-Lymphocytes / Q000276:immunology*
D004768:Enterotoxins; D016693:Receptors, Antigen, T-Cell, alpha-beta; C081278:T cell receptor Vbeta6.7a, human; D004247:DNA