title: Detection of Mycobacterium bovis infection in cattle using an immunoassay for bovine soluble interleukin-2 receptor-alpha (sIL-2R-alpha) produced by peripheral blood T-lymphocytes following incubation with tuberculin PPD.
abstract: After activation of T-lymphocytes with antigen there is an increase in the expression of interleukin-2 receptor-alpha (IL-2R-alpha) followed by the release of a soluble form of the molecule (sIL-2R-alpha) from the membrane of the stimulated cells. The present study investigates the novel use of the release of sIL-2R-alpha from activated T-lymphocytes as a marker of cell-mediated immunity (CMI) in cattle infected with Mycobacterium bovis. An enzyme immunoassay was used to detect sIL-2R-alpha produced following incubation of bovine peripheral blood mononuclear cells with mycobacterial antigens. Using this assay, 63/67 cattle naturally infected with M. bovis were identified whereas only 1/51 uninfected animals were considered to give a positive result. This assay is more convenient to use than lymphocyte proliferation assays which involve the use of radionucleosides. It should prove useful for monitoring the immunological activation of bovine T-lymphocytes in a variety of situations including the development of CMI responses in cattle to novel mycobacterial antigens or potential vaccines.
authors.affiliation: Department of Large Animal Clinical Studies, Faculty of Veterinary Medicine, University College Dublin, Ballsbridge, Ireland.
authors.forename: E M
authors.initials: EM
authors.lastname: Nualláin
authors.forename: W C
authors.initials: WC
authors.lastname: Davis
authors.forename: E
authors.initials: E
authors.lastname: Costello
authors.forename: J M
authors.initials: JM
authors.lastname: Pollock
authors.forename: M L
authors.initials: ML
authors.lastname: Monaghan
mesh_terms: D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000175:diagnosis* / Q000276:immunology; D002478:Cells, Cultured; D007118:Immunoassay / Q000662:veterinary; D008213:Lymphocyte Activation / Q000276:immunology; D009163:Mycobacterium bovis / Q000276:immunology; D015375:Receptors, Interleukin-2 / Q000032:analysis* / Q000096:biosynthesis*; D012995:Solubility; D013601:T-Lymphocytes / Q000378:metabolism*; D014373:Tuberculin / Q000032:analysis* / Q000276:immunology*; D014374:Tuberculin Test / Q000662:veterinary; D014380:Tuberculosis, Bovine / Q000175:diagnosis* / Q000276:immunology
chemical_list: D015375:Receptors, Interleukin-2; D014373:Tuberculin