title: Mature but not immature Fas ligand (CD95L)-transduced human monocyte-derived dendritic cells are protected from Fas-mediated apoptosis and can be used as killer APC.
abstract: Several in vitro and animal studies have been performed to modulate the interaction of APCs and T cells by Fas (CD95/Apo-1) signaling to delete activated T cells in an Ag-specific manner. However, due to the difficulties in vector generation and low transduction frequencies, similar studies with primary human APC are still lacking. To evaluate whether Fas ligand (FasL/CD95L) expressing killer APC could be generated from primary human APC, monocyte-derived dendritic cells (DC) were transduced using the inducible Cre/Loxp adenovirus vector system. Combined transduction of DC by AdLoxpFasL and AxCANCre, but not single transduction with these vectors, resulted in dose- and time-dependent expression of FasL in >70% of mature DC (mDC), whereas <20% of immature DC (iDC) expressed FasL. In addition, transduction by AdLoxpFasL and AxCANCre induced apoptosis in >80% of iDC, whereas FasL-expressing mDC were protected from FasL/Fas (CD95/Apo-1)-mediated apoptosis despite coexpression of Fas. FasL-expressing mDC eliminated Fas(+) Jurkat T cells as well as activated primary T cells by apoptosis, whereas nonactivated primary T cells were not deleted. Induction of apoptosis in Fas(+) target cells required expression of FasL in DC and cell-to-cell contact between effector and target cell, and was not dependent on soluble FasL. Induction of apoptosis in Fas(+) target cells required expression of FasL in DC, cell-to-cell contact between effector and target cell, and was not dependent on soluble FasL. The present results demonstrate that FasL-expressing killer APC can be generated from human monocyte-derived mDC using adenoviral gene transfer. Our results support the strategy to use killer APCs as immunomodulatory cells for the treatment of autoimmune disease and allograft rejection.
authors.affiliation: Department of Internal Medicine I, Regensburg, Germany.
authors.forename: Sabine
authors.initials: S
authors.lastname: Hoves
authors.forename: Stefan W
authors.initials: SW
authors.lastname: Krause
authors.forename: Dagmar
authors.initials: D
authors.lastname: Halbritter
authors.forename: Huang-Ge
authors.initials: HG
authors.lastname: Zhang
authors.forename: John D
authors.initials: JD
authors.lastname: Mountz
authors.forename: Jürgen
authors.initials: J
authors.lastname: Schölmerich
authors.forename: Martin
authors.initials: M
authors.lastname: Fleck
mesh_terms: D000256:Adenoviridae / Q000235:genetics; D000938:Antigen-Presenting Cells / Q000276:immunology* / Q000378:metabolism; D017209:Apoptosis / Q000235:genetics / Q000276:immunology*; D002454:Cell Differentiation / Q000235:genetics / Q000276:immunology; D002460:Cell Line; D002478:Cells, Cultured; D018920:Coculture Techniques; D003601:Cytotoxicity Tests, Immunologic; D003713:Dendritic Cells / Q000276:immunology* / Q000378:metabolism; D053222:Fas Ligand Protein; D005822:Genetic Vectors; D049452:Green Fluorescent Proteins; D006801:Humans; D019426:Integrases / Q000235:genetics; D019169:Jurkat Cells; D007694:Killer Cells, Natural / Q000276:immunology* / Q000378:metabolism; D008024:Ligands; D008164:Luminescent Proteins / Q000235:genetics; D008213:Lymphocyte Activation / Q000235:genetics; D008212:Lymphocyte Depletion; D008562:Membrane Glycoproteins / Q000096:biosynthesis / Q000235:genetics* / Q000502:physiology; D009000:Monocytes / Q000276:immunology* / Q000378:metabolism; D011995:Recombination, Genetic; D012995:Solubility; D016176:T-Lymphocyte Subsets / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D014161:Transduction, Genetic; D014764:Viral Proteins / Q000235:genetics; D019014:fas Receptor / Q000096:biosynthesis / Q000502:physiology*
chemical_list: C505661:FASLG protein, human; D053222:Fas Ligand Protein; D008024:Ligands; D008164:Luminescent Proteins; D008562:Membrane Glycoproteins; D014764:Viral Proteins; D019014:fas Receptor; D049452:Green Fluorescent Proteins; C045073:Cre recombinase; D019426:Integrases