Genes encoding ligands for deletion of V beta 11 T cells cosegregate with mammary tumour virus genomes.
The T-cell receptor (TCR) repertoire is selected in the thymus after rearrangement of genes encoding TCR alpha and beta chains. Selection is based on the recognition by newly emergent T cells of self-ligands associated with molecules of the major histocompatibility complex: some combinations result in positive selection, others in negative selection. Negative selection, or clonal deletion, is an important mechanism for eliminating autoreactive T cells. A group of self-ligands involved in clonal deletion was identified because they, like exogenous superantigens, were recognized by almost all T cells expressing particular TCR V beta genes. V beta 17a T cells are deleted by a tissue-specific ligand; V beta 6, V beta 7, V beta 8.1 and V beta 9 T cells are deleted by the minor lymphocyte-stimulating (Mls) determinant Mls-1a; V beta 3 T cells by Mls-2a and Mls-3a; V beta 11 T cells by ligands encoded by independently segregating genes; and V beta 5 T cells by ligands encoded by two genes. Chromosome mapping using recombinant inbred strains of mice and classic backcrosses show that Mls-1a in DBA/2 mice is encoded on chromosome 1, that one of the two ligand genes for deletion of V beta 5 T cells maps to chromosome 12 and that a ligand gene for V beta 11 deletion is linked to the CD8 locus on chromosome 6. Here we present evidence from three sets of backcross mice for concordance between V beta 11 deletion ligand genes on chromosomes 6, 12 and 14 and endogenous mouse mammary tumour virus integrant (Mtv) genomes.(ABSTRACT TRUNCATED AT 250 WORDS)
Dyson
P J
PJ
Clinical Research Centre, Harrow, Middlesex, UK.
Knight
A M
AM
Fairchild
S
S
Simpson
E
E
Tomonari
K
K
D000818:Animals; D015139:Blotting, Southern; D002470:Cell Survival; D002874:Chromosome Mapping; D007108:Immune Tolerance; D008024:Ligands; D008324:Mammary Tumor Virus, Mouse / Q000235:genetics*; D051379:Mice; D008815:Mice, Inbred Strains; D011948:Receptors, Antigen, T-Cell / Q000378:metabolism*; D016693:Receptors, Antigen, T-Cell, alpha-beta; D016176:T-Lymphocyte Subsets / Q000166:cytology*
D008024:Ligands; D011948:Receptors, Antigen, T-Cell; D016693:Receptors, Antigen, T-Cell, alpha-beta