title: Cutting Edge: Rag deletion in peripheral T cells blocks TCR revision.
abstract: Mature CD4(+)Vbeta5(+) T cells that recognize a peripherally expressed endogenous superantigen are tolerized either by deletion or TCR revision. In Vbeta5 transgenic mice, this latter tolerance pathway results in the appearance of CD4(+)Vbeta5(-)TCRbeta(+) T cells, coinciding with Rag1, Rag2, and TdT expression and the accumulation of V(beta)-DJ(beta) recombination intermediates in peripheral CD4(+) T cells. Because postthymic RAG-dependent TCR rearrangement has remained controversial, we sought to definitively determine whether TCR revision is an extrathymic process that occurs in mature peripheral T cells. We show in this study that Rag deletion in post-positive selection T cells in Vbeta5 transgenic mice blocks TCR revision in vivo and that mature peripheral T cells sorted to remove cells bearing endogenous TCRbeta-chains can express newly generated TCRbeta molecules in adoptive hosts. These findings unambiguously demonstrate postthymic, RAG-dependent TCR rearrangement and define TCR revision as a tolerance pathway that targets mature peripheral CD4(+) T cells.
authors.affiliation: Department of Immunology, University of Washington, Seattle, WA 98195, USA.
authors.forename: J Scott
authors.initials: JS
authors.lastname: Hale
authors.forename: Kristina T
authors.initials: KT
authors.lastname: Ames
authors.forename: Tamar E
authors.initials: TE
authors.lastname: Boursalian
authors.forename: Pamela J
authors.initials: PJ
authors.lastname: Fink
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D002469:Cell Separation; D004268:DNA-Binding Proteins / Q000235:genetics / Q000276:immunology*; D005434:Flow Cytometry; D015329:Gene Rearrangement, T-Lymphocyte / Q000235:genetics*; D007108:Immune Tolerance / Q000235:genetics / Q000276:immunology; D051379:Mice; D008822:Mice, Transgenic; D011948:Receptors, Antigen, T-Cell / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D004268:DNA-Binding Proteins; C499308:Rag2 protein, mouse; D011948:Receptors, Antigen, T-Cell