Influence of viral superantigens on V beta- and V alpha-specific positive and negative selection.
In mice, V beta-specific negative selection is mediated by a number of superantigens encoded by various mouse mammary tumor viruses. We have identified Mtv-3, Mtv-27, Mtv-44, Mtv-8, Mtv-9, Mtv-11, and MMTV(D2.GD), and have confirmed Mtv-1. Although specificities of superantigens correlate well with sequences of their carboxy terminal regions, Mtv-44 appears to be an exception: the product is specific for V beta 3, V beta 6, V beta 8.1, and V beta 9. It remains to be determined whether Mtv-44 produces one or two different superantigens to exhibit this specificity. V beta 5+ T-cell deletion is induced by two groups of superantigens: V beta 3-specific superantigens encoded by Mtv-1, Mtv-3, Mtv-6, Mtv-13, Mtv-27, and Mtv-44, and V beta 11-specific superantigens encoded by Mtv-8, Mtv-9, and Mtv-11. Furthermore, these V beta 3-specific superantigens are also specific for V beta 17a(cz). In contrast, V beta-specific positive selection and V alpha-specific positive and negative selection do not seem to involve non-H-2 (super)antigens, although their involvement can not be excluded. In the near future, superantigens, powerful modulators of T-cell functions, will be exploited for clinical applications.
Tomonari
K
K
Transplantation Biology Section, MRC Clinical Research Centre, Harrow, UK.
Fairchild
S
S
Rosenwasser
O A
OA
D000595:Amino Acid Sequence; D000818:Animals; D000914:Antibodies, Viral; D000956:Antigens, Viral / Q000235:genetics; D017353:Gene Deletion; D008324:Mammary Tumor Virus, Mouse / Q000235:genetics / Q000276:immunology; D051379:Mice; D008969:Molecular Sequence Data; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000235:genetics; D013601:T-Lymphocytes / Q000276:immunology
D000914:Antibodies, Viral; D000956:Antigens, Viral; D016693:Receptors, Antigen, T-Cell, alpha-beta