title: Evidence for a superantigen in human tuberculosis.
abstract: T cells are not only required for resistance to tuberculosis, but they likely contribute to the tissue damage characteristic of the disease. To define better the T cell populations that contribute to the immunopathogenesis of human tuberculosis, we investigated the T cell receptor (TCR) beta chain repertoire expressed in patients with tuberculous pleuritis. Analysis by polymerase chain reaction and flow cytometry indicated an expansion of V beta 8+ T cells at the site of disease in some donors, suggesting the possibility that Mycobacterium tuberculosis contains a superantigen. M. tuberculosis induced strong T cell proliferative responses in tuberculin-negative healthy donors in vitro, with preferential expansion of V beta 8+ T cells, independent of the CDR3 region. T cell stimulation was MHC class II-dependent and did not require antigen processing by the antigen-presenting cells. These findings are consistent with the presence of a superantigen in M. tuberculosis, aspects of which may contribute to the immunopathology of tuberculosis and to the adjuvant properties of M. tuberculosis.
authors.affiliation: Division of Dermatology, University of California, Los Angeles, School of Medicine 90024.
authors.forename: J D
authors.initials: JD
authors.lastname: Ohmen
authors.forename: P F
authors.initials: PF
authors.lastname: Barnes
authors.forename: C L
authors.initials: CL
authors.lastname: Grisso
authors.forename: B R
authors.initials: BR
authors.lastname: Bloom
authors.forename: R L
authors.initials: RL
authors.lastname: Modlin
mesh_terms: D000595:Amino Acid Sequence; D017951:Antigen Presentation; D015704:CD4 Antigens / Q000378:metabolism; D016827:CD8 Antigens / Q000378:metabolism; D014644:Genetic Variation; D000949:Histocompatibility Antigens Class II / Q000378:metabolism; D006801:Humans; D066298:In Vitro Techniques; D008213:Lymphocyte Activation; D008969:Molecular Sequence Data; D009169:Mycobacterium tuberculosis / Q000276:immunology*; D016133:Polymerase Chain Reaction; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000235:genetics; D018089:Superantigens / Q000302:isolation & purification*; D016176:T-Lymphocyte Subsets / Q000276:immunology; D014373:Tuberculin / Q000276:immunology; D014396:Tuberculosis, Pleural / Q000276:immunology*
chemical_list: D015704:CD4 Antigens; D016827:CD8 Antigens; D000949:Histocompatibility Antigens Class II; D016693:Receptors, Antigen, T-Cell, alpha-beta; D018089:Superantigens; D014373:Tuberculin