title: Analysis of retroorbital T cell antigen receptor variable region gene usage in patients with Graves' ophthalmopathy.
abstract: To date, it has remained unclear whether orbit-infiltrating T cells in patients with Graves' ophthalmopathy (GO) represent a primary immune response in which a limited number of T cell clones driving the disease are activated against specific antigens, or whether they participate in a non-specific inflammatory process. To characterize these T cells at the molecular level, we examined the T cell antigen receptor (TcR) V gene repertoire in situ in retroorbital tissue specimens obtained from patients with early and late stages of clinically severe GO and from patients with non-GO orbital conditions. Ribonucleic acid extracted from orbital tissue and peripheral blood lymphocytes (PBL) was reverse transcribed and amplified using the polymerase chain reaction and 22 V alpha and 24 V beta gene-specific oligonucleotide primers. The resulting TcR V alpha and V beta transcripts were verified by Southern hybridization analysis using TcR C region-specific, digoxigenin-labeled oligonucleotide probes. Compared with matched PBL, the retroorbital TcR V alpha and V beta gene repertoire expressed was heterogeneous, but revealed marked restriction of V gene usage in samples derived from retroorbital connective tissue and extraocular muscle of all eight patients with severe GO of short duration studied. In contrast, greater diversity of the TcR V beta gene repertoire and loss of TcR V alpha gene restriction was noted in four patients with late GO undergoing reconstructive eye muscle surgery. Unrestricted TcR V gene usage was demonstrated in orbital tissue and PBL samples obtained from control subjects. These results suggest that retroorbital TcR V gene usage is variable but markedly restricted during the earlier stages of GO. With increasing disease duration, greater diversity of the TcR V gene repertoire appears to develop, and oligoclonality of the T cell response may be lost. Selection of patients with early stages of GO will be important when further dissecting TcR usage and antigen specificity of orbit-infiltrating T lymphocytes in GO.
authors.affiliation: Molecular Thyroid Research Unit, Klinikum Innenstadt, Ludwig-Maximilians-Universität, München, Germany.
authors.forename: A E
authors.initials: AE
authors.lastname: Heufelder
authors.forename: S
authors.initials: S
authors.lastname: Herterich
authors.forename: G
authors.initials: G
authors.lastname: Ernst
authors.forename: R S
authors.initials: RS
authors.lastname: Bahn
authors.forename: P C
authors.initials: PC
authors.lastname: Scriba
mesh_terms: D000328:Adult; D001483:Base Sequence; D015139:Blotting, Southern; D015536:Down-Regulation; D005260:Female; D006111:Graves Disease / Q000235:genetics / Q000276:immunology*; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D009915:Orbit; D010641:Phenotype; D016133:Polymerase Chain Reaction; D011948:Receptors, Antigen, T-Cell / Q000235:genetics*; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D011948:Receptors, Antigen, T-Cell