title: A key role for poly(ADP-ribose) polymerase-1 activity during human dendritic cell maturation.
abstract: Poly(ADP-ribose) (PAR) polymerase (PARP)-1 is a nuclear enzyme regulating protein that functions by targeting PAR chains. Besides its classic role in DNA repair, PARP-1 is emerging as a key transcriptional regulator in different cell types including the immune ones. In this study, we investigated the role of PARP-1 in human dendritic cell (DC) function. We report that both PARP-1 mRNA and protein levels significantly increased during in vitro DC differentiation from monocytes. Of note, inhibitors of PARP-1 such as phenanthridinone and thieno[2,3-c]isoquinolin-5-one reduced expression of CD86 and CD83 in a concentration-dependent manner, having no effects on expression of CD80 and HLA-DR in mature DCs. In the same cultures, PARP-1 inhibitors also reduced production of IL-12 and IL-10. Addition of exogenous IL-12 to the culture medium partially restored CD86 expression in DCs exposed to PARP-1 inhibitors. In line with the role of PAR formation in NF-kappaB-dependent transactivation, we also report that phenanthridinone and thieno[2,3-c]isoquinolin-5-one impaired NF-kappaB and AP-1 subunit DNA binding activity in cellular extract of activated DCs. Finally, we show that PARP-1 inhibitors reduced the T cell allostimulatory activity of mature DCs, and that this reduction was prevented when DCs matured in the presence of PARP-1 inhibitors plus IL-12. Of note, nonproliferating T cells exposed to PARP-1 inhibitor-challenged DCs could undergo efficient proliferation when exposed to a subsequent activation stimulus such as anti-CD3 plus anti-CD-28. Together, data provide evidence for a key role of PARP-1 and poly ADP-ribosylation in DC immunocompetence and underscore the relevance of PARP-1 inhibitors to treatment of immune disorders.
authors.affiliation: Department of Pharmacology, University of Florence, Viale Pieraccini 6, 50139 Florence, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Aldinucci
authors.forename: Gianni
authors.initials: G
authors.lastname: Gerlini
authors.forename: Silvia
authors.initials: S
authors.lastname: Fossati
authors.forename: Giulia
authors.initials: G
authors.lastname: Cipriani
authors.forename: Clara
authors.initials: C
authors.lastname: Ballerini
authors.forename: Tiziana
authors.initials: T
authors.lastname: Biagioli
authors.forename: Nicola
authors.initials: N
authors.lastname: Pimpinelli
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Borgognoni
authors.forename: Luca
authors.initials: L
authors.lastname: Massacesi
authors.forename: Flavio
authors.initials: F
authors.lastname: Moroni
authors.forename: Alberto
authors.initials: A
authors.lastname: Chiarugi
mesh_terms: D002454:Cell Differentiation / Q000187:drug effects / Q000276:immunology*; D002478:Cells, Cultured; D004268:DNA-Binding Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism; D003713:Dendritic Cells / Q000166:cytology* / Q000187:drug effects / Q000201:enzymology*; D015536:Down-Regulation / Q000187:drug effects / Q000276:immunology; D004789:Enzyme Activation / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006801:Humans; D016130:Immunophenotyping; D016753:Interleukin-10 / Q000037:antagonists & inhibitors / Q000096:biosynthesis; D018664:Interleukin-12 / Q000037:antagonists & inhibitors / Q000096:biosynthesis; D008213:Lymphocyte Activation / Q000187:drug effects; D009000:Monocytes / Q000166:cytology / Q000201:enzymology; D016328:NF-kappa B / Q000037:antagonists & inhibitors / Q000378:metabolism; D000071137:Poly (ADP-Ribose) Polymerase-1; D000067856:Poly(ADP-ribose) Polymerase Inhibitors; D011065:Poly(ADP-ribose) Polymerases / Q000096:biosynthesis / Q000378:metabolism*; D018808:Transcription Factor AP-1 / Q000037:antagonists & inhibitors / Q000378:metabolism; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
chemical_list: D004268:DNA-Binding Proteins; D004791:Enzyme Inhibitors; D016328:NF-kappa B; D000067856:Poly(ADP-ribose) Polymerase Inhibitors; D018808:Transcription Factor AP-1; D016753:Interleukin-10; D018664:Interleukin-12; C499320:PARP1 protein, human; D000071137:Poly (ADP-Ribose) Polymerase-1; D011065:Poly(ADP-ribose) Polymerases; D048051:p38 Mitogen-Activated Protein Kinases