title: 4-1BB ligand-mediated costimulation of human T cells induces CD4 and CD8 T cell expansion, cytokine production, and the development of cytolytic effector function.
abstract: 4-1BB (CD137) is a costimulatory member of the TNFR family expressed on activated T cells. Its ligand, 4-1BBL, is expressed on activated APC. In the mouse, CD8 T cells are preferentially activated by agonistic anti-murine 4-1BB Abs. However, murine 4-1BBL can stimulate both CD4 and CD8 T cells. To date, there are only limited data on the effects of 4-1BBL on human T cell responses. To further understand the role of 4-1BBL in human T cell responses, we compared human CD4 and CD8 T cell responses to transfected human 4-1BBL plus TCR-mediated stimulation. Both human CD4 and CD8 T cells responded to 4-1BBL. The presence of 4-1BBL on the APC led to increased expansion, cytokine production, and the development of cytolytic effector function by human T cells. In unfractionated T cell cultures, CD4 and CD8 T cells could expand to a similar extent in response to signals through the TCR and 4-1BB, as measured by CFSE labeling and by quantitating T cell numbers in the cultures. In contrast to the results with total T cells, isolated CD8 T cells produced less IL-2 and expanded to a lesser extent than isolated CD4 T cells responding to 4-1BBL. Thus, 4-1BBL is most effective when both CD4 and CD8 T cells are included in the cultures. CD28 and 4-1BB were found to synergize in the induction of IL-2 by human T cells, and CTLA-Ig partially blocked 4-1BBL-dependent IL-2 production. However, a portion of the 4-1BBL-mediated effects were independent of CD28-B7 interaction.
authors: Department of Immunology, University of Toronto, Toronto, Ontario M5S 1A8, Canada.
authors: Tao
authors: T
authors: Wen
authors: Jacob
authors: J
authors: Bukczynski
authors: Tania H
authors: TH
authors: Watts
mesh_terms: D053330:4-1BB Ligand; D000276:Adjuvants, Immunologic / Q000235:genetics / Q000502:physiology; D000818:Animals; D015703:Antigens, CD; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology* / Q000276:immunology* / Q000378:metabolism; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology* / Q000276:immunology* / Q000378:metabolism; D002455:Cell Division / Q000276:immunology; D016207:Cytokines / Q000096:biosynthesis*; D003602:Cytotoxicity, Immunologic / Q000235:genetics; D006801:Humans; D007371:Interferon-gamma / Q000096:biosynthesis; D007376:Interleukin-2 / Q000096:biosynthesis; D008024:Ligands; D008213:Lymphocyte Activation / Q000235:genetics; D051379:Mice; D017475:Receptors, Nerve Growth Factor / Q000096:biosynthesis; D018124:Receptors, Tumor Necrosis Factor / Q000096:biosynthesis; D016176:T-Lymphocyte Subsets / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D014162:Transfection; D014407:Tumor Cells, Cultured; D053261:Tumor Necrosis Factor Receptor Superfamily, Member 9; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000502:physiology*
chemical_list: D053330:4-1BB Ligand; D000276:Adjuvants, Immunologic; D015703:Antigens, CD; D016207:Cytokines; D007376:Interleukin-2; D008024:Ligands; D017475:Receptors, Nerve Growth Factor; D018124:Receptors, Tumor Necrosis Factor; C505714:TNFRSF9 protein, human; C505974:TNFSF9 protein, human; C505715:Tnfrsf9 protein, mouse; C505975:Tnfsf9 protein, mouse; D053261:Tumor Necrosis Factor Receptor Superfamily, Member 9; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma