Human CD8 + T cells display a differential ability to undergo cytokine-driven bystander activation

• Published in: Cellular immunology 2011, Vol.272 (1), p.79-86
• Main Authors: Bou Ghanem, Elsa N., D’Orazio, Sarah E.F.
• Format: Article
• Language: English
• Subjects: Adult; Animals; Bystander Effect - immunology; CD8-Positive T-Lymphocytes - drug effects; CD8-Positive T-Lymphocytes - immunology; CD8-Positive T-Lymphocytes - metabolism; Enzyme-Linked Immunosorbent Assay; Female; Flow Cytometry; Humans; IFNγ; IL-12; Immunity, Innate; Immunologic Memory - drug effects; Immunologic Memory - immunology; Innate immunity; Interferon-gamma - biosynthesis; Interferon-gamma - immunology; Interleukin-12 - immunology; Interleukin-12 - pharmacology; Interleukin-18 - immunology; Interleukin-18 - pharmacology; Listeria monocytogenes; Listeria monocytogenes - drug effects; Listeria monocytogenes - immunology; Listeriosis - immunology; Listeriosis - metabolism; Listeriosis - microbiology; Lymphocyte Activation - drug effects; Lymphocyte Activation - immunology; Male; Memory; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Species Specificity; T-Lymphocyte Subsets - drug effects; T-Lymphocyte Subsets - immunology
• ISSN: 0008-8749; 1090-2163
• DOI: 10.1016/j.cellimm.2011.09.003

► Peripheral blood mononuclear cells from individual donors secreted varying amounts of IL-12 after L. monocytogenes infection. ► Human CD8 + T cells from different blood donors varied in their innate responsiveness to stimulation with IL-12 plus IL-18. ► CD8 + T cells from a subset of donors (12.5%) failed to rapidly secrete IFNγ. ► The magnitude of the rapid IFNγ response correlated with intrinsic T cell responsiveness, not the amount of IL-12 produced. A subset of CD44 hiCD8 + T cells in some, but not all mice, can be induced to rapidly secrete IFNγ during infection with Listeria monocytogenes. This response is dependent on the presence of both IL-12 and IL-18 and does not require engagement of the T cell receptor. In this study, we demonstrate that human CD8 + T cells also vary widely in their ability to secrete IFNγ within 15 h of either Listeria infection or cytokine stimulation. The magnitude of the rapid IFNγ response correlated more closely with the intrinsic responsiveness of the T cells to cytokine stimulation rather than the amount of IL-12 produced. CD8 + T cells from 2 out of 16 blood donors (12.5%) failed to generate a significant IFNγ response. These results demonstrate that bystander activation of CD8 + T cells varies among individuals and validate further study of the differential responses observed using BALB/c vs. C57BL/6 mice.