title: CD56+ human blood dendritic cells effectively promote TH1-type gammadelta T-cell responses.
abstract: CD56+ human dendritic cells (DCs) have recently been shown to differentiate from monocytes in response to GM-CSF and type 1 interferon in vitro. We show here that CD56+ cells freshly isolated from human peripheral blood contain a substantial subset of CD14+CD86+HLA-DR+ cells, which have the appearance of intermediate-sized lymphocytes but spontaneously differentiate into enlarged DC-like cells with substantially increased HLA-DR and CD86 expression or into fully mature CD83+ DCs in response to appropriate cytokines. Stimulation of CD56+ cells containing both DCs and abundant gammadelta T cells with zoledronate and interleukin-2 (IL-2) resulted in the rapid expansion of gammadelta T cells as well as in IFN-gamma, TNF-alpha, and IL-1beta but not in IL-4, IL-10, or IL-17 production. IFN-gamma, TNF-alpha, and IL-1beta production were almost completely abolished by depleting CD14+ cells from the CD56+ subset before stimulation. Likewise, depletion of CD14+ cells dramatically impaired gammadelta T-cell expansion. IFN-gamma production could also be blocked by neutralizing the effects of endogenous IL-1beta and TNF-alpha. Conversely, addition of recombinant IL-1beta, TNF-alpha, or both further enhanced IFN-gamma production and strongly up-regulated IL-6 production. Our data indicate that CD56+ DCs from human blood are capable of stimulating CD56+ gammadelta T cells, which may be harnessed for immunotherapy.
authors.affiliation: Cell Therapy Unit, Department of Urology, Innsbruck Medical University, Innsbruck, Austria.
authors.forename: Georg
authors.initials: G
authors.lastname: Gruenbacher
authors.forename: Hubert
authors.initials: H
authors.lastname: Gander
authors.forename: Andrea
authors.initials: A
authors.lastname: Rahm
authors.forename: Walter
authors.initials: W
authors.lastname: Nussbaumer
authors.forename: Nikolaus
authors.initials: N
authors.lastname: Romani
authors.forename: Martin
authors.initials: M
authors.lastname: Thurnher
mesh_terms: D019002:CD56 Antigen / Q000276:immunology* / Q000378:metabolism; D002454:Cell Differentiation / Q000276:immunology; D016207:Cytokines / Q000096:biosynthesis; D003713:Dendritic Cells / Q000166:cytology / Q000276:immunology*; D005434:Flow Cytometry; D006801:Humans; D007118:Immunoassay; D018950:Lipopolysaccharide Receptors / Q000276:immunology / Q000378:metabolism; D008213:Lymphocyte Activation / Q000276:immunology; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000276:immunology*; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D018417:Th1 Cells / Q000276:immunology*
chemical_list: D019002:CD56 Antigen; D016207:Cytokines; D018950:Lipopolysaccharide Receptors; D016692:Receptors, Antigen, T-Cell, gamma-delta