title: Expression and presentation of endogenous mouse mammary tumor virus superantigens by thymic and splenic dendritic cells and B cells.
abstract: Tolerance against superantigens (SAgs) encoded by endogenous mouse mammary tumor virus (Mtv) loci involves the intrathymic deletion of SAg-reactive T cells expressing a particular TCR V beta-chain, presumably upon presentation of the SAg by specialized APC. However, although the role of dendritic cells (DC) in the induction of tolerance against conventional Ags has been demonstrated, little is known about the role played by DC in tolerance induction against Mtv SAgs. Moreover, there is conflicting evidence concerning the capacity of DC to express and present Mtv SAgs. In this report we have analyzed the expression of Mtv SAgs in highly purified thymic and splenic DC and B cells by reverse transcriptase-PCR, using primers amplifying Mtv SAg-specific spliced mRNAs. DC express Mtv SAgs at levels comparable to B cells, but display a differential expression pattern of the various Mtv loci compared with B cells. Furthermore, our results show that DC are able to induce the deletion of SAg-reactive thymocytes in an in vitro assay, indicating that Mtv SAgs are functionally expressed on the DC surface. Collectively, our data are consistent with the hypothesis that DC play a role in the induction of intrathymic tolerance to Mtv SAgs.
authors.affiliation: Ludwig Institute for Cancer Research, Lausanne Branch, University of Lausanne, Epalinges, Switzerland.
authors.forename: C
authors.initials: C
authors.lastname: Ardavín
authors.forename: G
authors.initials: G
authors.lastname: Waanders
authors.forename: I
authors.initials: I
authors.lastname: Ferrero
authors.forename: F
authors.initials: F
authors.lastname: Anjuère
authors.forename: H
authors.initials: H
authors.lastname: Acha-Orbea
authors.forename: H R
authors.initials: HR
authors.lastname: MacDonald
mesh_terms: D000818:Animals; D017951:Antigen Presentation; D001402:B-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D001483:Base Sequence; D017637:Clonal Deletion; D003713:Dendritic Cells / Q000276:immunology* / Q000378:metabolism; D007108:Immune Tolerance; D008324:Mammary Tumor Virus, Mouse / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008811:Mice, Inbred DBA; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000235:genetics; D013154:Spleen / Q000166:cytology* / Q000276:immunology / Q000378:metabolism / Q000821:virology; D018089:Superantigens / Q000096:biosynthesis / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology; D013950:Thymus Gland / Q000166:cytology* / Q000276:immunology / Q000378:metabolism / Q000821:virology
chemical_list: D016693:Receptors, Antigen, T-Cell, alpha-beta; D018089:Superantigens