title: IRF-4 expression in the human myeloid lineage: up-regulation during dendritic cell differentiation and inhibition by 1alpha,25-dihydroxyvitamin D3.
abstract: Interferon (IFN) regulatory factor (IRF)-4 is a lymphoid- and myeloid-restricted transcription factor of the IRF family. We analyzed its expression during differentiation of human monocytes along the macrophage or the dendritic cell (DC) pathway and in blood myeloid and plasmacytoid DC (M-DC and P-DC, respectively) subsets. Monocyte differentiation into DC, driven by granulocyte macrophage-colony stimulating factor (GM-CSF)/interleukin-4 or GM-CSF/IFN-beta, resulted in a strong up-regulation of IRF-4 mRNA and protein, which was further increased by lipopolysaccharide. It is interesting that 1alpha,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)], a potent inhibitor of DC differentiation, completely abolished IRF-4 up-regulation. IRF-4 was also detected in blood P-DC and M-DC. However, up-regulation upon in vitro culture and down-regulation by 1,25(OH)(2)D(3) was observed in M-DC but not in P-DC. These results point to IRF-4 as a potential player in human myeloid DC differentiation and as a novel target for the immunomodulatory activity of 1,25(OH)(2)D(3).
authors.affiliation: Department of Cell Biology and Neurosciences, Istituto Superiore di Sanità, Rome, Italy.
authors.forename: Maria Cristina
authors.initials: MC
authors.lastname: Gauzzi
authors.forename: Cristina
authors.initials: C
authors.lastname: Purificato
authors.forename: Lucia
authors.initials: L
authors.lastname: Conti
authors.forename: Luciano
authors.initials: L
authors.lastname: Adorini
authors.forename: Filippo
authors.initials: F
authors.lastname: Belardelli
authors.forename: Sandra
authors.initials: S
authors.lastname: Gessani
mesh_terms: D002117:Calcitriol / Q000494:pharmacology*; D002454:Cell Differentiation; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D003713:Dendritic Cells / Q000187:drug effects* / Q000378:metabolism; D015870:Gene Expression / Q000187:drug effects; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology; D006801:Humans; D050835:Interferon Regulatory Factors; D022423:Myeloid Cells / Q000187:drug effects / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D015854:Up-Regulation; D000099218:Interferon Regulatory Factor-4
chemical_list: D002117:Calcitriol; D004268:DNA-Binding Proteins; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D050835:Interferon Regulatory Factors; D012333:RNA, Messenger; D014157:Transcription Factors; D000099218:Interferon Regulatory Factor-4