title: Expression and function of the IL-2 receptor in activated human plasmacytoid dendritic cells.
abstract: Human and mouse plasmacytoid dendritic cells (PDC) express IL-2 mRNA specifically upon TLR stimulation, but not under CD40L stimulation. Even though the expression of the IL-2R by PDC has been described, the functional implications of this expression remain unknown. Here, we investigated the expression and function of the IL-2R in activated human PDC. The IL-2Ralpha chain, CD25, is expressed in both CpG- and CD40L-activated PDC. CD25 expression is a relatively rapid event, as the receptor was detected 6 h after the initial activation signal. Exogenous IL-2 added to CD40L-activated PDC increased the expression of CD25, enhanced the secretion of pro-inflammatory cytokines and promotes PDC survival. CpG-activated PDC cultured in the presence of IL-2R-blocking monoclonal antibodies showed a reduced expression of pro-inflammatory cytokines, especially TNF-alpha. This reduction was dose and time dependent, suggesting a regulatory role of IL-2 in TNF secretion that might occur at the post-transcriptional level. These results indicate that the expression of the IL-2R is relevant to human PDC activation, and that IL-2 may be an important auto- and/or paracrine factor modulating the activation and survival of PDC. Finally, CD25 expression may be considered as a useful early activation marker for human PDC.
authors.affiliation: Laboratory of Immunobiology for Research and Applications to Diagnosis, Blood and Tissue Bank, Department of Cell Biology, Physiology and Immunology, Universitat Autònoma de Barcelona, Barcelona, Spain.
authors.forename: Mar
authors.initials: M
authors.lastname: Naranjo-Gómez
authors.forename: Harold
authors.initials: H
authors.lastname: Oliva
authors.forename: Nuria
authors.initials: N
authors.lastname: Climent
authors.forename: Marco A
authors.initials: MA
authors.lastname: Fernández
authors.forename: Marta
authors.initials: M
authors.lastname: Ruiz-Riol
authors.forename: Margarita
authors.initials: M
authors.lastname: Bofill
authors.forename: José M
authors.initials: JM
authors.lastname: Gatell
authors.forename: Teresa
authors.initials: T
authors.lastname: Gallart
authors.forename: Ricardo
authors.initials: R
authors.lastname: Pujol-Borrell
authors.forename: Francesc E
authors.initials: FE
authors.lastname: Borràs
mesh_terms: D000276:Adjuvants, Immunologic; D023201:CD40 Ligand / Q000276:immunology / Q000378:metabolism; D002478:Cells, Cultured; D018899:CpG Islands / Q000276:immunology; D003713:Dendritic Cells / Q000276:immunology* / Q000378:metabolism; D005434:Flow Cytometry; D006801:Humans; D053645:Interleukin-2 Receptor alpha Subunit / Q000276:immunology / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis; D015375:Receptors, Interleukin-2 / Q000276:immunology* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis / Q000276:immunology
chemical_list: D000276:Adjuvants, Immunologic; D053645:Interleukin-2 Receptor alpha Subunit; D012333:RNA, Messenger; D015375:Receptors, Interleukin-2; D014409:Tumor Necrosis Factor-alpha; D023201:CD40 Ligand