title: CD4+ T cell-independent maintenance and expansion of memory CD8+ T cells derived from in vitro dendritic cell activation.
abstract: CD4+ T cells are essential for the maintenance of CD8+ memory T (Tm) cells following acute infection, but the importance of CD4+ T cells for the maintenance and expansion of CD8+ Tm cells to non-infectious antigens remains mostly unknown. Here, we showed that ovalbumin (OVA)-specific CD8+ Tm cell precursors derived from in vitro stimulation of TCR transgenic OT I CD8+ T cells with OVA protein-pulsed bone marrow-derived dendritic cells (DCOVA) can give rise to functional CD8+ Tm cells after adoptively transferred into mice. These CD8+ Tm cells can be maintained and remain fully functional in CD4+ T cell-absent environments in vivo. Furthermore, CD4+ T cells are not essential for the expansion of these CD8+ Tm cells. Finally, these in vitro DCOVA-activated CD8+ Tm cells maintained in CD4-deficient mice are also able to confer fully protective immunity against a later challenge of OVA-expressing tumor cells. Collectively, these findings demonstrate that in contrast to acute infections, maintenance and expansion of CD8+ Tm cells after priming with OVA protein-pulsed dendritic cells are independent of CD4+ T cells.
authors.affiliation: Research Unit, Saskatchewan Cancer Agency, Department of Microbiology and Immunology, College of Medicine, University of Saskatchewan, 20 Campus Drive, Saskatoon, Canada S7N 4H4.
authors.forename: Meiqing
authors.initials: M
authors.lastname: Shi
authors.forename: Jim
authors.initials: J
authors.lastname: Xiang
mesh_terms: D000818:Animals; D001854:Bone Marrow Cells / Q000276:immunology; D015704:CD4 Antigens / Q000235:genetics / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D002450:Cell Communication / Q000276:immunology; D049109:Cell Proliferation; D002478:Cells, Cultured; D003713:Dendritic Cells / Q000276:immunology*; D007156:Immunologic Memory / Q000235:genetics / Q000276:immunology*; D008213:Lymphocyte Activation / Q000235:genetics / Q000276:immunology*; D051379:Mice; D018345:Mice, Knockout; D009369:Neoplasms / Q000235:genetics / Q000276:immunology*
chemical_list: D015704:CD4 Antigens