title: Induction of interleukin-1 in human monocytes by the superantigen staphylococcal enterotoxin A requires the participation of T cells.
abstract: Nanogram quantities of the bacterial superantigen Staphylococcal Enterotoxin A (SEA) induced significant amounts of extracellular IL-1 alpha and IL-1 beta in human peripheral blood mononuclear cells. Induction of maximal IL-1 alpha and IL-1 beta levels by lipopolysaccharide (LPS) required microgram quantities. LPS induced detectable extracellular IL-1 content within 3-6 hr and maximal levels were detected already after 12 hr. Induction of IL-1 production by SEA showed a delayed release with peak values after 24-48 hr. IL-1 beta was the major species of IL-1 seen in both SEA- and LPS-stimulated culture supernatants. SEA was in general a relatively stronger inducer of extracellular IL-1 alpha than LPS. SEA-induced extracellular IL-1 production in human monocytes was entirely dependent on the presence of T cells, whereas addition of T cells to LPS-stimulated purified human monocytes only marginally enhanced the extracellular IL-1 production. The capacity to induce extracellular IL-1 production in monocytes in response to SEA was high in the CD4+ 45RO+ memory T cell subset, whereas CD4+ 45RA+ naive T cells and CD8+ T cells had lower IL-1-inducing capacity. The T cell help for IL-1 production could not be replaced by a panel of T cell-derived recombinant lymphokines added to SEA-stimulated monocytes, including IFN-gamma and TNF, indicating the participation of cell membrane-bound ligands or hitherto unidentified soluble mediators.
authors.affiliation: Wallenberg Laboratory, Department of Tumor Immunology, University of Lund, Sweden.
authors.forename: A
authors.initials: A
authors.lastname: Gjörloff
authors.forename: H
authors.initials: H
authors.lastname: Fischer
authors.forename: G
authors.initials: G
authors.lastname: Hedlund
authors.forename: J
authors.initials: J
authors.lastname: Hansson
authors.forename: J S
authors.initials: JS
authors.lastname: Kenney
authors.forename: A C
authors.initials: AC
authors.lastname: Allison
authors.forename: H O
authors.initials: HO
authors.lastname: Sjögren
authors.forename: M
authors.initials: M
authors.lastname: Dohlsten
mesh_terms: D000942:Antigens, Bacterial / Q000276:immunology*; D002478:Cells, Cultured; D016207:Cytokines / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004768:Enterotoxins / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D006801:Humans; D007156:Immunologic Memory; D007375:Interleukin-1 / Q000032:analysis / Q000096:biosynthesis*; D008070:Lipopolysaccharides / Q000494:pharmacology; D009000:Monocytes / Q000502:physiology*; D013211:Staphylococcus aureus / Q000276:immunology*; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D013997:Time Factors
chemical_list: D000942:Antigens, Bacterial; D016207:Cytokines; D004768:Enterotoxins; D007375:Interleukin-1; D008070:Lipopolysaccharides; C026066:enterotoxin A, Staphylococcal