title: Putative IKDCs are functionally and developmentally similar to natural killer cells, but not to dendritic cells.
abstract: Interferon-producing killer dendritic cells (IKDCs) have been described as possessing the lytic potential of NK cells and the antigen-presenting capacity of dendritic cells (DCs). In this study, we examine the lytic function and antigen-presenting capacity of mouse spleen IKDCs, including those found in DC preparations. IKDCs efficiently killed NK cell targets, without requiring additional activation stimuli. However, in our hands, when exposed to protein antigen or to MHC class II peptide, IKDCs induced little or no T cell proliferation relative to conventional DCs or plasmacytoid DCs, either before or after activation with CpG, or in several disease models. Certain developmental features indicated that IKDCs resembled NK cells more than DCs. IKDCs, like NK cells, did not express the transcription factor PU.1 and were absent from recombinase activating gene-2-null, common gamma-chain-null (Rag2(-/-)Il2rg(-/-)) mice. When cultured with IL-15 and -18, IKDCs proliferated extensively, like NK cells. Under these conditions, a proportion of expanded IKDCs and NK cells expressed high levels of surface MHC class II. However, even such MHC class II(+) IKDCs and NK cells induced poor T cell proliferative responses compared with DCs. Thus, IKDCs resemble NK cells functionally, and neither cell type could be induced to be effective antigen-presenting cells.
authors.affiliation: Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, 3050, Australia. caminschi@wehi.edu.au
authors.forename: Irina
authors.initials: I
authors.lastname: Caminschi
authors.forename: Fatma
authors.initials: F
authors.lastname: Ahmet
authors.forename: Klaus
authors.initials: K
authors.lastname: Heger
authors.forename: Jason
authors.initials: J
authors.lastname: Brady
authors.forename: Stephen L
authors.initials: SL
authors.lastname: Nutt
authors.forename: David
authors.initials: D
authors.lastname: Vremec
authors.forename: Suzanne
authors.initials: S
authors.lastname: Pietersz
authors.forename: Mireille H
authors.initials: MH
authors.lastname: Lahoud
authors.forename: Louis
authors.initials: L
authors.lastname: Schofield
authors.forename: Diana S
authors.initials: DS
authors.lastname: Hansen
authors.forename: Meredith
authors.initials: M
authors.lastname: O'Keeffe
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Smyth
authors.forename: Sammy
authors.initials: S
authors.lastname: Bedoui
authors.forename: Gayle M
authors.initials: GM
authors.lastname: Davey
authors.forename: Jose A
authors.initials: JA
authors.lastname: Villadangos
authors.forename: William R
authors.initials: WR
authors.lastname: Heath
authors.forename: Ken
authors.initials: K
authors.lastname: Shortman
mesh_terms: D000818:Animals; D003713:Dendritic Cells / Q000145:classification / Q000276:immunology*; D000949:Histocompatibility Antigens Class II / Q000276:immunology; D016130:Immunophenotyping; D039421:Integrin alpha2 / Q000032:analysis / Q000276:immunology; D007372:Interferons / Q000096:biosynthesis* / Q000276:immunology; D007694:Killer Cells, Natural / Q000145:classification / Q000276:immunology*; D017493:Leukocyte Common Antigens / Q000032:analysis / Q000276:immunology; D008213:Lymphocyte Activation; D051379:Mice; D013154:Spleen / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D000949:Histocompatibility Antigens Class II; D039421:Integrin alpha2; D007372:Interferons; D017493:Leukocyte Common Antigens