title: Antigen recognition and immunomodulation by gamma delta T cells in bovine tuberculosis.
abstract: This report describes the in vitro proliferative responses of peripheral blood gammadelta T cells to defined mycobacterial protein Ags and the immunomodulatory effect of gammadelta T cells in cattle infected with Mycobacterium bovis. gammadelta T cell responses were specific to M. bovis infection because they were detected in cattle either experimentally or naturally infected with M. bovis, but were not present in uninfected controls. Proliferating gammadelta T cell cultures produced enhanced levels of IFN-gamma and TGF-beta, but not IL-2 in response to the more immunodominant mycobacterial AGS: Depletion of gammadelta T cells from PBMC resulted in an increased Ag-specific proliferation in half the animals tested, indicating a suppressive effect of gammadelta T cells upon other (alphabeta) T cell responses. Because gammadelta T cells constitute a major T cell population in the peripheral blood of cattle, the activities of gammadelta T cells described in this report could make a significant contribution to the immune response in bovine tuberculosis.
authors: TB Research Group, Veterinary Laboratories Agency, Surrey, United Kingdom. srhodes.vla@gtnet.gov.uk
authors: S G
authors: SG
authors: Rhodes
authors: R G
authors: RG
authors: Hewinson
authors: H M
authors: HM
authors: Vordermeier
mesh_terms: D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology / Q000378:metabolism / Q000382:microbiology; D000942:Antigens, Bacterial / Q000276:immunology* / Q000378:metabolism*; D002417:Cattle; D002450:Cell Communication / Q000276:immunology*; D002478:Cells, Cultured; D018984:Epitopes, T-Lymphocyte / Q000276:immunology; D005260:Female; D007111:Immunity, Cellular; D007371:Interferon-gamma / Q000096:biosynthesis; D007376:Interleukin-2 / Q000096:biosynthesis; D008213:Lymphocyte Activation / Q000276:immunology; D008212:Lymphocyte Depletion; D009163:Mycobacterium bovis / Q000276:immunology*; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000276:immunology*; D016176:T-Lymphocyte Subsets / Q000276:immunology* / Q000378:metabolism / Q000382:microbiology; D016212:Transforming Growth Factor beta / Q000096:biosynthesis; D014380:Tuberculosis, Bovine / Q000276:immunology*; D015854:Up-Regulation / Q000276:immunology
chemical_list: D000942:Antigens, Bacterial; D018984:Epitopes, T-Lymphocyte; D007376:Interleukin-2; D016692:Receptors, Antigen, T-Cell, gamma-delta; D016212:Transforming Growth Factor beta; D007371:Interferon-gamma