Homogenous junctional sequence of the V14+ T-cell antigen receptor alpha chain expanded in unprimed mice.
Nucleotide sequences of VJ (variable-joining) junctional regions of V14+ alpha-chain T-cell receptor genes show that most V alpha 14+ T cells use one alpha chain (V alpha 14J alpha 281 with a one-nucleotide N region, which is frequently used in keyhole limpet hemocyanin-specific suppressor T-cell hybridomas) in unprimed mice. Moreover, the frequency of this alpha-chain expression was greater than 1.5% of the total alpha chains found in laboratory strains, including B10 congenic mice. This is about 10(4) times higher than was expected. The V14J281 alpha-chain expression was relatively low but was significant in CD4+/CD8+ immature thymocytes and became quite high in mature single-positive T cells, implying that this alpha chain is selected during T-cell maturation. V14J281 expression increased with time after birth and reached a maximum at around 5 weeks of age. The ligand seems to be a self molecule and to be present in laboratory strains but to be absent in a wild mouse, Mus musculus molossinus, because bone marrow chimeras clearly showed that bone marrow cells derived from Mus musculus molossinus negative for this alpha chain raised V14J281-positive T cells in a C57BL/6 environment. The above results suggest that there are some selection mechanisms for this cell type other than those for conventional alpha beta T cells and also that the homogenous VJ junction of the V14J281 alpha chain plays a pivotal role in the selection of the T cell and its ligand reactivity.
Koseki
H
H
Division of Molecular Immunology, School of Medicine, Chiba University, Japan.
Imai
K
K
Nakayama
F
F
Sado
T
T
Moriwaki
K
K
Taniguchi
M
M
D000818:Animals; D000831:Animals, Newborn; D001483:Base Sequence; D051379:Mice; D008810:Mice, Inbred C57BL; D008815:Mice, Inbred Strains; D008969:Molecular Sequence Data; D015345:Oligonucleotide Probes; D016133:Polymerase Chain Reaction; D011948:Receptors, Antigen, T-Cell / Q000235:genetics*; D012260:Ribonucleases; D013154:Spleen / Q000276:immunology; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology*; D013950:Thymus Gland / Q000276:immunology; D014158:Transcription, Genetic
D015345:Oligonucleotide Probes; D011948:Receptors, Antigen, T-Cell; D012260:Ribonucleases