title: Direct CD4 help provision following interaction of memory CD4 and CD8 T cells with distinct antigen-presenting dendritic cells.
abstract: Accumulating evidence suggests that CD4 help is needed at the memory stage to mount effective secondary CD8 T cell responses. In this paper, we report that memory CD4 T cells can provide efficient help to memory CD8 T cells after interaction of the two lymphocytes with distinct dendritic cells. Provision of help to CD8 T cells required direct cell-cell contact and involved both IL-2 and CD40 ligation, within a CD4-CD8 T cell synapse. Thus, following antigenic interaction with APCs, activated memory CD4 and CD8 T cells appear to separate from their respective APCs before meeting each other for help provision, regardless of their Ag specificity. CD4 help for memory CD8 T cells therefore appears to be conditioned primarily not by Ag specificity but by activation status.
authors.affiliation: Institut National de la Santé et de la Recherche Médicale U-1012, Université Paris-Sud, Faculté de Médecine, 94276 Le Kremlin-Bicêtre, France.
authors.forename: Marie-Ghislaine
authors.initials: MG
authors.lastname: de Goër de Herve
authors.forename: Bamory
authors.initials: B
authors.lastname: Dembele
authors.forename: Mélissa
authors.initials: M
authors.lastname: Vallée
authors.forename: Florence
authors.initials: F
authors.lastname: Herr
authors.forename: Anne
authors.initials: A
authors.lastname: Cariou
authors.forename: Yassine
authors.initials: Y
authors.lastname: Taoufik
mesh_terms: D000818:Animals; D017951:Antigen Presentation / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology* / Q000378:metabolism; D019013:CD40 Antigens / Q000276:immunology / Q000378:metabolism; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology* / Q000378:metabolism; D018827:Carcinoma, Lewis Lung / Q000276:immunology / Q000473:pathology; D002450:Cell Communication / Q000276:immunology; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D018920:Coculture Techniques; D003602:Cytotoxicity, Immunologic / Q000276:immunology; D003713:Dendritic Cells / Q000166:cytology / Q000276:immunology*; D005260:Female; D005434:Flow Cytometry; D053804:Granzymes / Q000378:metabolism; D007156:Immunologic Memory / Q000276:immunology; D007376:Interleukin-2 / Q000276:immunology / Q000378:metabolism; D008213:Lymphocyte Activation / Q000276:immunology; D008285:Major Histocompatibility Complex / Q000235:genetics / Q000276:immunology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout
chemical_list: D019013:CD40 Antigens; D007376:Interleukin-2; D053804:Granzymes