title: Characterization of in vivo expanded OspA-specific human T-cell clones.
abstract: A panel of CD4 T-cell clones was isolated from synovial fluid by single cell flow cytometry from a patient with treatment-resistant Lyme arthritis using a DRB1*0401 major histocompatibility complex (MHC) class II tetramer covalently loaded with outer surface protein A (OspA) peptide164-175, an immunodominant epitope of Borrelia burgdorferi. Sequencing of the T-cell receptors of the OspA reactive clones showed significant skewing of the T-cell receptor repertoire. Of the 101 T-cell clones sequenced, 81 possessed TCR beta chains that were present in at least one other clone isolated. Complete sequencing of both alpha and beta chains of a subset of clones showed that at least two distinct T-cell clones were expanded in vivo. Binding studies using a panel of Ala-substituted peptide ligands were performed to determine potential MHC binding sites of the OspAp164-175 to DRB1*0401. In addition, T-cell clones were tested functionally for their reactivity to the wild-type peptide as well as to altered peptide ligands (APLs) and peptide libraries based on the OspA epitope in order to determine the TCR contact residues and the stringency in T cell recognition. We are among the first to define the characteristics of TCR usage of T cells isolated from an inflamed immune compartment in an individual with an autoimmune disease potentially triggered by a microbial antigen.
authors.affiliation: Laboratory of Molecular Immunology, Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, USA.
authors.forename: Lara J
authors.initials: LJ
authors.lastname: Ausubel
authors.forename: Kevin C
authors.initials: KC
authors.lastname: O'Connor
authors.forename: Clare
authors.initials: C
authors.lastname: Baecher-Allen
authors.forename: Christina
authors.initials: C
authors.lastname: Trollmo
authors.forename: Benedikt
authors.initials: B
authors.lastname: Kessler
authors.forename: Brian
authors.initials: B
authors.lastname: Hekking
authors.forename: David
authors.initials: D
authors.lastname: Merritt
authors.forename: Abbie L
authors.initials: AL
authors.lastname: Meyer
authors.forename: Bill
authors.initials: B
authors.lastname: Kwok
authors.forename: Hidde
authors.initials: H
authors.lastname: Ploegh
authors.forename: Brigitte T
authors.initials: BT
authors.lastname: Huber
authors.forename: David A
authors.initials: DA
authors.lastname: Hafler
mesh_terms: D000595:Amino Acid Sequence; D000954:Antigens, Surface / Q000737:chemistry* / Q000235:genetics / Q000276:immunology; D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry* / Q000235:genetics / Q000276:immunology; D001428:Bacterial Vaccines; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D002999:Clone Cells; D006684:HLA-DR Antigens / Q000378:metabolism; D059811:HLA-DRB1 Chains; D006801:Humans; D008074:Lipoproteins / Q000737:chemistry* / Q000235:genetics / Q000276:immunology; D008193:Lyme Disease / Q000276:immunology*; D008213:Lymphocyte Activation; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000378:metabolism; D011948:Receptors, Antigen, T-Cell / Q000737:chemistry / Q000235:genetics; D013582:Synovial Fluid / Q000737:chemistry / Q000166:cytology / Q000276:immunology
chemical_list: D000954:Antigens, Surface; D001425:Bacterial Outer Membrane Proteins; D001428:Bacterial Vaccines; D006684:HLA-DR Antigens; D059811:HLA-DRB1 Chains; C553505:HLA-DRB1*04:01 antigen; D008074:Lipoproteins; C072045:OspA protein; D010446:Peptide Fragments; D011948:Receptors, Antigen, T-Cell