title: Direct enumeration of Borrelia-reactive CD4 T cells ex vivo by using MHC class II tetramers.
abstract: We characterized antigen-specific CD4(+) T cells in six patients with treatment-resistant Lyme arthritis, using an HLA-DRB1*0401 major histocompatibility complex (MHC) class II tetramer covalently loaded with OspA(164-175), an immunodominant epitope of Borrelia burgdorferi. Direct analysis of OspA-tetramer binding CD4(+) cells in patients expressing the HLA-DRB1*0401 allele revealed frequencies of between <0.005 and 0.1% in peripheral blood (n = 6), and between <0.005 and 3.1% in synovial fluid (n = 3). OspA-tetramer(+)CD4(+) cells were directly cloned at 1 cell per well and expanded by mitogen and IL-2 on allogeneic feeder cells. As measured by [(3)H]thymidine incorporation, 95% of 168 T cell clones from synovial fluid binding the OspA-tetramer were antigen-reactive. Clones generated from peripheral blood revealed a different pattern of responsiveness when compared with clones generated from synovial fluid, as measured by proliferation, IFN-gamma, and IL-13 secretion. These clones, selected on the basis of their peptide binding, also responded to whole protein, but with a different cytokine profile. Our studies demonstrate that MHC class II tetramers can be used in humans to directly identify, isolate, and characterize antigen-reactive T cells from an inflammatory compartment.
authors.affiliation: Tufts University School of Medicine, Department of Pathology, Boston, MA 02111, USA.
authors.forename: A L
authors.initials: AL
authors.lastname: Meyer
authors.forename: C
authors.initials: C
authors.lastname: Trollmo
authors.forename: F
authors.initials: F
authors.lastname: Crawford
authors.forename: P
authors.initials: P
authors.lastname: Marrack
authors.forename: A C
authors.initials: AC
authors.lastname: Steere
authors.forename: B T
authors.initials: BT
authors.lastname: Huber
authors.forename: J
authors.initials: J
authors.lastname: Kappler
authors.forename: D A
authors.initials: DA
authors.lastname: Hafler
mesh_terms: D000954:Antigens, Surface / Q000276:immunology; D001425:Bacterial Outer Membrane Proteins / Q000276:immunology; D001428:Bacterial Vaccines; D001704:Biopolymers; D015748:Borrelia burgdorferi Group / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D002999:Clone Cells; D016207:Cytokines / Q000276:immunology; D004306:Dose-Response Relationship, Immunologic; D006684:HLA-DR Antigens / Q000008:administration & dosage / Q000276:immunology*; D059811:HLA-DRB1 Chains; D006801:Humans; D066298:In Vitro Techniques; D008074:Lipoproteins; D008193:Lyme Disease / Q000276:immunology; D022123:Lyme Disease Vaccines / Q000276:immunology
chemical_list: D000954:Antigens, Surface; D001425:Bacterial Outer Membrane Proteins; D001428:Bacterial Vaccines; D001704:Biopolymers; D016207:Cytokines; D006684:HLA-DR Antigens; D059811:HLA-DRB1 Chains; C553505:HLA-DRB1*04:01 antigen; D008074:Lipoproteins; D022123:Lyme Disease Vaccines; C072045:OspA protein