title: Efficient presentation of endogenous superantigen by H-2Aq.
abstract: Endogenous superantigens encoded by mouse mammary tumor viruses associate with MHC class II and interact with T cells bearing particular V beta gene segments. H-2E is more efficient at presentation than H-2A, indeed Aq has not been shown to be capable of presenting endogenous superantigens. Atypically, the superantigen vSAG-3 encoded by Mtv-3 is presented efficiently in non-obese diabetic (H-2g7) mice by H-2A; we have examined the independent contributions of vSAG-3 and Ag7 to this process. Ag7 was not found to have a more general ability to efficiently present endogenous superantigens other than Mtv-3. Examination of Mtv-3-mediated thymic deletion of V beta 3+ thymocytes in the presence of H-2q additionally demonstrated the efficient presentation of vSAG-3 by Aq. Interaction of vSAG-3 with Aq and Ag7 is likely to reflect the unique sequence of Mtv-3 within the second polymorphic region previously implicated in MHC class II binding. The demonstration that mouse endogenous superantigens can be presented by a wider range of MHC haplotypes than previously thought is further evidence for their immunological impact on the mouse population.
authors.affiliation: Clinical Sciences Centre, Imperial College School of Medicine, Hammersmith Hospital, London, GB.
authors.forename: P J
authors.initials: PJ
authors.lastname: Dyson
authors.forename: J
authors.initials: J
authors.lastname: Elliott
authors.forename: A N
authors.initials: AN
authors.lastname: Antoniou
authors.forename: K T
authors.initials: KT
authors.lastname: Corley
mesh_terms: D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology; D000956:Antigens, Viral / Q000378:metabolism*; D006183:H-2 Antigens / Q000378:metabolism*; D006239:Haplotypes; D008285:Major Histocompatibility Complex; D008324:Mammary Tumor Virus, Mouse / Q000276:immunology*; D008562:Membrane Glycoproteins / Q000378:metabolism; D051379:Mice; D016688:Mice, Inbred NOD / Q000276:immunology; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000032:analysis; D018089:Superantigens / Q000378:metabolism*; D016176:T-Lymphocyte Subsets / Q000276:immunology
chemical_list: D000956:Antigens, Viral; D006183:H-2 Antigens; D008562:Membrane Glycoproteins; C095378:Mtv-7 superantigen, Mouse mammary tumor virus; D016693:Receptors, Antigen, T-Cell, alpha-beta; D018089:Superantigens