title: Mycobacterial crossreactivity of M. tuberculosis reactive T cell clones from naturally converted PPD positive healthy subjects.
abstract: Mycobacterium tuberculosis reactive CD4+, CD8- T cell clones were established from six naturally converted PPD positive healthy subjects by using whole bacilli as the primary stimulation antigen in vitro. Antigen specificity of the T cell clones was mapped by testing their proliferative response against a panel of pathogenic and environmental mycobacterial species. The crossreactivity patterns obtained showed that the T cell clones distributed along a spectrum from reactivity restricted to the M. tuberculosis complex to broadly crossreactive clones recognizing all mycobacterial species tested. Two of the T cell clones were able to discriminate between M. tuberculosis and M. bovis BCG, and importantly one of these clones was exclusively specific to M. tuberculosis. All of the CD4+ T cell clones tested, displayed MHC class II restricted cytotoxicity against macrophages pulsed with M. tuberculosis. In addition, some of these clones secreted GM-CSF upon antigen stimulation. The T cell clones described here represent relevant tools to identify and characterize target antigens of the immune response against M. tuberculosis with relevance to diagnosis and subunit vaccine design.
authors.affiliation: Department of Vaccinology, National Institute of Public Health, Torshov, Oslo, Norway. oftung@online.no
authors.forename: F
authors.initials: F
authors.lastname: Oftung
authors.forename: E
authors.initials: E
authors.lastname: Borka
authors.forename: G
authors.initials: G
authors.lastname: Kvalheim
authors.forename: A S
authors.initials: AS
authors.lastname: Mustafa
mesh_terms: D000942:Antigens, Bacterial / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D002999:Clone Cells; D003429:Cross Reactions; D003601:Cytotoxicity Tests, Immunologic; D018604:Epitope Mapping; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000378:metabolism; D006801:Humans; D009161:Mycobacterium / Q000276:immunology*; D009169:Mycobacterium tuberculosis / Q000276:immunology*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D014373:Tuberculin / Q000276:immunology; D014374:Tuberculin Test
chemical_list: D000942:Antigens, Bacterial; D014373:Tuberculin; D016178:Granulocyte-Macrophage Colony-Stimulating Factor