Selective induction of CD8+ cytotoxic T lymphocyte effector function by staphylococcus enterotoxin B.
Upon encounter with its antigenic stimulus, CTL characteristically proliferate, produce cytokines, and lyse the Ag-presenting cell in an attempt to impede further infection. Superantigens are extremely efficient immunostimulatory proteins that promote high levels of proliferation and massive cytokine production in reactive T cells. We compared the activation of murine influenza-specific CD8+ CTL clones stimulated with either influenza peptide or the superantigen staphylococcus enterotoxin B (SEB). We found that influenza peptide/MHC and SEB appeared equally capable of eliciting proliferation and IFN-gamma production. However, while influenza peptide/MHC elicited both perforin- and Fas ligand (FasL)/Fas (CD95L/CD95)-mediated cytolytic mechanisms, SEB was unable to trigger perforin-mediated cytolysis or serine esterase release. Examination of intracellular Ca2+ mobilization events revealed that the ability to trigger intracellular Ca2+ flux was not comparable between influenza peptide and SEB. SEB stimulated only a small rise in levels of intracellular Ca2+, at times indistinguishable from background. These findings indicate that the short-term cytolytic potential of superantigen-activated CD8+ CTL clones appears to be restricted to FasL/Fas (CD95L/CD95) mediated cytolysis.
Fuller
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CL
Department of Microbiology, Beirne B. Carter Center for Immunology Research, Health Sciences Center, University of Virginia, Charlottesville 22908, USA.
Braciale
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VL
D000818:Animals; D000956:Antigens, Viral / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism; D020013:Calcium Signaling / Q000276:immunology; D002999:Clone Cells; D003602:Cytotoxicity, Immunologic; D004768:Enterotoxins / Q000276:immunology*; D004789:Enzyme Activation / Q000276:immunology; D004950:Esterases / Q000378:metabolism; D053222:Fas Ligand Protein; D009980:Influenza A virus / Q000276:immunology; D007371:Interferon-gamma / Q000096:biosynthesis; D007424:Intracellular Fluid / Q000276:immunology / Q000378:metabolism; D008024:Ligands; D008213:Lymphocyte Activation; D008562:Membrane Glycoproteins / Q000096:biosynthesis / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D010455:Peptides / Q000276:immunology; D054353:Perforin; D052899:Pore Forming Cytotoxic Proteins; D015375:Receptors, Interleukin-2 / Q000096:biosynthesis; D013211:Staphylococcus aureus / Q000276:immunology*; D013602:T-Lymphocytes, Cytotoxic / Q000201:enzymology / Q000276:immunology* / Q000378:metabolism; D015854:Up-Regulation / Q000276:immunology; D019014:fas Receptor / Q000096:biosynthesis
D000956:Antigens, Viral; D004768:Enterotoxins; D053222:Fas Ligand Protein; C505658:Fasl protein, mouse; D008024:Ligands; D008562:Membrane Glycoproteins; D010455:Peptides; D052899:Pore Forming Cytotoxic Proteins; D015375:Receptors, Interleukin-2; D019014:fas Receptor; D054353:Perforin; C031818:enterotoxin B, staphylococcal; D007371:Interferon-gamma; D004950:Esterases; C022635:serine esterase