T-cell receptor delta-chain can substitute for alpha to form a beta delta heterodimer.
Specific monoclonal antibodies have made possible the identification of two T-cell antigen receptor (TCR) heterodimers, alpha beta TCR and gamma delta TCR. Formation of these receptors is largely separated by the preferential pairing of alpha-TCR with beta and gamma-TCR with delta, the sequential rearrangement and expression of the TCR loci during thymic development and the deletion of the delta-loci either prior to or concomitant with alpha-rearrangement in alpha beta TCR cells. Here we show that delta-TCR can substitute for alpha in pairing with beta to form a beta delta heterodimer. This receptor is expressed on the cell surface of the T-leukaemia cell line DND41 as analysed with beta- and delta-specific monoclonal antibodies. We suggest that a variety of factors including, for example, the deletion of the delta-TCR loci, can now be understood as exclusion mechanisms operating to prevent not only the formation of gamma delta receptors, but also of beta delta T-cell receptors, thereby promoting the numerically dominant alpha beta TCR lineage. Nevertheless, some developing T-cells that do not rearrange the alpha-loci may express the beta delta TCR as described here.
Hochstenbach
F
F
Laboratory of Immunochemistry, Dana-Farber Cancer Institute, Boston, Massachusetts.
Brenner
M B
MB
D000818:Animals; D000911:Antibodies, Monoclonal; D002874:Chromosome Mapping; D015329:Gene Rearrangement, T-Lymphocyte; D051379:Mice; D011948:Receptors, Antigen, T-Cell / Q000096:biosynthesis* / Q000235:genetics; D016693:Receptors, Antigen, T-Cell, alpha-beta; D016692:Receptors, Antigen, T-Cell, gamma-delta
D000911:Antibodies, Monoclonal; D011948:Receptors, Antigen, T-Cell; D016693:Receptors, Antigen, T-Cell, alpha-beta; D016692:Receptors, Antigen, T-Cell, gamma-delta