title: A simple and sensitive bioassay for the detection of IL-2 activity.
abstract: A simple, one-step quantitative assay for the detection of biologically active interleukin-2 (IL-2) is described. It is based on culture of pure CD3+ T cells which have been positively selected from blood mononuclear cells by particle (M450)-bound anti-CD3 monoclonal antibody (mAb). During culture, activation of the T cells via CD3 will occur, leading to expression of IL-2 receptors but not IL-2 production. By adding IL-2 a proliferative response is evoked, giving a linear dose-response curve for IL-2 concentrations between 0.01-20 U/ml. The cells were unresponsive to IL-1, IL-4, tumor necrosis factor alpha (TNF-alpha), interferon-alpha (IFN-alpha), IFN-gamma, phytohemagglutinin and concanavalin A. The responsiveness to IL-2 was enhanced by TNF-alpha and inhibited by IFN-alpha, while the other tested lymphokines and mitogens did not influence the proliferative response. Antibodies to IL-2 and to IL-2 receptor suppressed the IL-2 response in a dose-dependent manner. The method is both simple and specific, and obviates the necessity for keeping assay cells in long term culture.
authors.affiliation: Institute of Transplantation Immunology, National Hospital, Oslo, Norway.
authors.forename: T
authors.initials: T
authors.lastname: Leivestad
authors.forename: G
authors.initials: G
authors.lastname: Gaudernack
authors.forename: R
authors.initials: R
authors.lastname: Halvorsen
authors.forename: E
authors.initials: E
authors.lastname: Thorsby
mesh_terms: D000911:Antibodies, Monoclonal; D000945:Antigens, Differentiation, T-Lymphocyte / Q000276:immunology; D017252:CD3 Complex; D002469:Cell Separation; D002478:Cells, Cultured; D004306:Dose-Response Relationship, Immunologic; D006801:Humans; D007376:Interleukin-2 / Q000032:analysis* / Q000502:physiology; D008213:Lymphocyte Activation; D008863:Microspheres; D008934:Mitogens; D010641:Phenotype; D011948:Receptors, Antigen, T-Cell / Q000276:immunology; D013601:T-Lymphocytes / Q000145:classification / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; D000945:Antigens, Differentiation, T-Lymphocyte; D017252:CD3 Complex; D007376:Interleukin-2; D008934:Mitogens; D011948:Receptors, Antigen, T-Cell