Superantigen-reactive human T cells express a biased repertoire of T-cell receptor V beta joining regions.
A major characteristic of superantigens is their ability to stimulate T cells based predominantly on the type of variable segment of the T-cell receptor (TCR) V beta chain. Recently, however, reports from several laboratories have also implied a role for non-V beta elements in superantigen binding. The goal of the present study was to determine whether TCR V beta-D beta-J beta joining sequences may influence the interaction of superantigens with their target cells. To ascertain how the actual TCR repertoire of superantigen-triggered cells deviates from the theoretical one, we generated a large panel of joining region sequences from TCR carrying the TCR V beta 12 and TCR V beta 5,1 regions. The 245 sequences analysed represent transcripts of T cells from the same donor triggered either with an anti-CD3 monoclonal antibody or with the Staphylococcus aureus enterotoxins. Comparison of the joining sequences of these different groups demonstrates a skewed J beta usage in the sequences derived from superantigen-triggered cells and also provides evidence that ascribes to the putative CDR3 region of V beta segments a role in superantigen recognition. Finally, the data presented give some hints of the regions of the putative CDR3 loop that may play a major role in this function.
Quiròs Roldan
E
E
Dept. of Chemistry, School of Medicine, University of Brescia, Italy.
Sottini
A
A
Imberti
L
L
Mattioli
S
S
Albertini
A
A
Primi
D
D
D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal / Q000276:immunology; D001483:Base Sequence; D004254:DNA Nucleotidyltransferases / Q000378:metabolism; D018076:DNA, Complementary / Q000235:genetics; D015333:Gene Rearrangement, beta-Chain T-Cell Antigen Receptor; D006801:Humans; D008213:Lymphocyte Activation; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D018075:RNA, Complementary / Q000235:genetics; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000235:genetics*; D016415:Sequence Alignment; D018089:Superantigens / Q000276:immunology*; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D045567:VDJ Recombinases
D000911:Antibodies, Monoclonal; D018076:DNA, Complementary; D018075:RNA, Complementary; D016693:Receptors, Antigen, T-Cell, alpha-beta; D018089:Superantigens; D004254:DNA Nucleotidyltransferases; D045567:VDJ Recombinases