Development and function of autospecific dual TCR+ T lymphocytes.
Recent studies have challenged the long held concept that each T lymphocyte expresses on its surface only a single, unique alphabetaTCR. Dual TCR+ T cells have been recognized, however, their origin and potential to escape screening for self-reactivity remain obscure. We now report the thymic generation of dual alphabetaTCR+ T cells in the H-2Db/H-Y-specific TCR transgenic (Tg) mouse. Dual TCR+ thymocytes were positively selected less efficiently than single TCR+ thymocytes, although a subset attained maturity. Importantly, when TCR Tg mice were bred onto a negatively selecting background, auto-specific cells survived central deletion and matured as CD4+ dual TCR+ cells. These cells were autoreactive when CD8 expression was restored. The existence of autospecific, dual TCR+ T cells may have implications for the maintenance of self tolerance.
Department of Immunology, University of Colorado Health Sciences Center, Denver 80262, USA.
R K
RK
Paterson
H
H
Bluethmann
P
P
Tseng
A
A
Dunlap
T H
TH
Finkel
D000818:Animals; D015551:Autoimmunity; D016827:CD8 Antigens / Q000096:biosynthesis; D006183:H-2 Antigens / Q000235:genetics*; D064532:Histocompatibility Antigen H-2D; D007108:Immune Tolerance; D015847:Interleukin-4 / Q000494:pharmacology; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D008822:Mice, Transgenic; D018448:Models, Immunological; D016693:Receptors, Antigen, T-Cell, alpha-beta; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D013950:Thymus Gland / Q000276:immunology*
D016827:CD8 Antigens; D006183:H-2 Antigens; D064532:Histocompatibility Antigen H-2D; D016693:Receptors, Antigen, T-Cell, alpha-beta; D015847:Interleukin-4