title: The generation of protective memory-like CD8+ T cells during homeostatic proliferation requires CD4+ T cells.
abstract: Antigen-specific memory T cells are a critical component of protective immunity because of their increased frequency and enhanced reactivity after restimulation. However, it is unclear whether 'memory-like' T cells generated during lymphopenia-induced homeostatic proliferation can also offer protection against pathogens. Here we show that homeostatic proliferation-induced memory (HP-memory) CD8(+) T cells controlled bacterial infection as effectively as 'true' memory CD8(+) T cells, but their protective capacity required the presence of CD4(+) T cells during homeostatic proliferation. The necessity for CD4 help was overcome, however, if the HP-memory CD8(+) T cells lacked expression of TRAIL (tumor necrosis factor-related apoptosis-inducing ligand; also called Apo-2L). Thus, like conventional CD8(+) memory T cells, the protective function of HP-memory CD8(+) T cells shows dependence on CD4(+) T cell help.
authors.affiliation: Department of Laboratory Medicine and Pathology, University of Minnesota Medical Center, Center for Immunology, Minneapolis, Minnesota 55454, USA.
authors.forename: Sara E
authors.initials: SE
authors.lastname: Hamilton
authors.forename: Monika C
authors.initials: MC
authors.lastname: Wolkers
authors.forename: Stephen P
authors.initials: SP
authors.lastname: Schoenberger
authors.forename: Stephen C
authors.initials: SC
authors.lastname: Jameson
mesh_terms: D019264:Adoptive Transfer; D000818:Animals; D051017:Apoptosis Regulatory Proteins / Q000378:metabolism; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology*; D049109:Cell Proliferation; D006706:Homeostasis / Q000276:immunology*; D007156:Immunologic Memory; D008088:Listeriosis / Q000276:immunology; D008562:Membrane Glycoproteins / Q000378:metabolism; D051379:Mice; D018345:Mice, Knockout; D053221:TNF-Related Apoptosis-Inducing Ligand; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D051017:Apoptosis Regulatory Proteins; D008562:Membrane Glycoproteins; D053221:TNF-Related Apoptosis-Inducing Ligand; C505654:Tnfsf10 protein, mouse; D014409:Tumor Necrosis Factor-alpha