title: From crucial to negligible: functional CD8⁺ T-cell responses and their dependence on CD4⁺ T-cell help.
abstract: CD8(+)  T cells play an important role in controlling pathogenic infections and are therefore key players in the immune response. It has been shown that among other factors CD4(+)  T cells can shape the magnitude as well as the quality of primary and/or secondary CD8(+)  T-cell responses. However, due to the complexity and the differences among diverse immunization or infection models, the overall requirement, the time points, as well as the specific mechanism(s) of CD4(+)  T-cell help may differ substantially. Here, we summarize current knowledge about the differential requirement of CD4(+)  T-cell help in promoting primary CD8(+)  T-cell responses as well as establishing functional memory CD8(+)  T cells in various experimental settings.
authors.affiliation: Institute for Microbiology, ETH Zürich, Zürich, Switzerland.
authors.forename: Melanie
authors.initials: M
authors.lastname: Wiesel
authors.forename: Annette
authors.initials: A
authors.lastname: Oxenius
mesh_terms: D000818:Animals; D001424:Bacterial Infections / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D002908:Chronic Disease; D006801:Humans; D007156:Immunologic Memory / Q000276:immunology; D007376:Interleukin-2 / Q000276:immunology; D008213:Lymphocyte Activation / Q000276:immunology; D051379:Mice; D014777:Virus Diseases / Q000276:immunology
chemical_list: D007376:Interleukin-2