title: Direct ex vivo analysis of activated, Fas-sensitive autoreactive T cells in human autoimmune disease.
abstract: The frequency of clonally expanded and persistent T cells recognizing the immunodominant autoantigenic peptide of myelin basic protein (MBP)p85-99 was directly measured ex vivo in subjects with typical relapsing remitting multiple sclerosis (MS). T cells expressing mRNA transcripts encoding T cell receptor (TCR)-alpha and -beta chains found in T cell clones previously isolated from these subjects recognizing the MBPp85-99 epitope were examined. In contrast to frequencies of 1 in 10(5)-10(6) as measured by limiting dilution analysis, estimates of the T cell frequencies expressing MBPp85-99-associated TCR chain transcripts were as high as 1 in 300. These high frequencies were confirmed by performing PCR on single T cells isolated by flow cytometry. MBPp85-99 TCR transcripts were present in IL-2 receptor alpha-positive T cells which were induced to undergo Fas-mediated cell death upon antigen stimulation. These data demonstrate that at least a subpopulation of patients with MS can have a very high frequency of activated autoreactive T cells.
authors.affiliation: Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA.
authors.forename: K D
authors.initials: KD
authors.lastname: Bieganowska
authors.forename: L J
authors.initials: LJ
authors.lastname: Ausubel
authors.forename: Y
authors.initials: Y
authors.lastname: Modabber
authors.forename: E
authors.initials: E
authors.lastname: Slovik
authors.forename: W
authors.initials: W
authors.lastname: Messersmith
authors.forename: D A
authors.initials: DA
authors.lastname: Hafler
mesh_terms: D001324:Autoantigens / Q000276:immunology; D001327:Autoimmune Diseases / Q000276:immunology*; D016923:Cell Death; D002999:Clone Cells; D015332:Gene Rearrangement, alpha-Chain T-Cell Antigen Receptor; D015333:Gene Rearrangement, beta-Chain T-Cell Antigen Receptor; D006801:Humans; D009103:Multiple Sclerosis / Q000276:immunology*; D004676:Myelin Basic Protein / Q000276:immunology; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000235:genetics; D013601:T-Lymphocytes / Q000276:immunology*; D019014:fas Receptor / Q000502:physiology*
chemical_list: D001324:Autoantigens; D004676:Myelin Basic Protein; D016693:Receptors, Antigen, T-Cell, alpha-beta; D019014:fas Receptor