Linkage of Mls genes to endogenous mammary tumour viruses of inbred mice

Abstract

T CELLS that recognize self antigen are clonally deleted in the thymus—a maturation process that occurs in the context of histo-compatibility molecules and the T-cell receptor. The minor lymphocyte stimulation antigens (Mis) effect these deletions through interactions with the Vβ portion of the T-cell receptor, thus mimicking bacterial 'superantigens'. Intrigued by the fact that each known Mls gene maps to the same chromosomal region as an endogenous mouse mammary tumour virus (Mtv), we re-evaluated the linkage relationships between the two gene families. Here we report perfect concordance in inbred and recombinant inbred mice between the presence of four Mtv proviruses with the expression of Mls gene products. These data suggest a general model in which mammary tumour virus gene products themselves are the ligands that shape a considerable portion of the immuno-logical repertoire of common laboratory mice.