title: Evidence for clonal selection of gamma/delta T cells in response to a human pathogen.
abstract: T cells bearing gamma/delta antigen receptors comprise a resident population of intraepithelial lymphocytes in organs such as skin, gut, and lungs, where they are strategically located to contribute to the initial defense against infection. An important unsolved question about antigen-driven gamma/delta T cell responses regards the breadth of their T cell receptor (TCR) repertoire, since many specific epithelial compartments in mice display limited diversity. We have examined the diversity of TCR delta gene expression among human gamma/delta T cells from skin lesions induced by intradermal challenge with Mycobacterium leprae. We show that the vast majority of gamma/delta cells from M. leprae lesions use either V delta 1-J delta 1 or V delta 2-J delta 1 gene rearrangements and, within a given region of the lesion, display limited junctional diversity. This contrasts markedly with the extensive diversity of gamma/delta T cells from peripheral blood of these same individuals, as well as skin from normal donors. These results indicate that the gamma/delta response to M. leprae involves the selection of a limited number of clones from among a diverse repertoire, probably in response to specific mycobacterial and/or host antigens.
authors.affiliation: Division of Dermatology, UCLA School of Medicine 90024.
authors.forename: K
authors.initials: K
authors.lastname: Uyemura
authors.forename: R J
authors.initials: RJ
authors.lastname: Deans
authors.forename: H
authors.initials: H
authors.lastname: Band
authors.forename: J
authors.initials: J
authors.lastname: Ohmen
authors.forename: G
authors.initials: G
authors.lastname: Panchamoorthy
authors.forename: C T
authors.initials: CT
authors.lastname: Morita
authors.forename: T H
authors.initials: TH
authors.lastname: Rea
authors.forename: R L
authors.initials: RL
authors.lastname: Modlin
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D002999:Clone Cells; D015329:Gene Rearrangement, T-Lymphocyte; D015334:Gene Rearrangement, gamma-Chain T-Cell Antigen Receptor; D006801:Humans; D007916:Lepromin / Q000276:immunology; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D011948:Receptors, Antigen, T-Cell / Q000502:physiology*; D016692:Receptors, Antigen, T-Cell, gamma-delta; D012867:Skin / Q000276:immunology; D012882:Skin Tests; D016176:T-Lymphocyte Subsets / Q000166:cytology / Q000276:immunology*
chemical_list: D011948:Receptors, Antigen, T-Cell; D016692:Receptors, Antigen, T-Cell, gamma-delta; D007916:Lepromin