title: Defects in CD54 and CD86 up-regulation by plasmacytoid dendritic cells during pregnancy.
abstract: Physiological modulation of the immune system is required for foetal tolerance during pregnancy. However, this immune regulation might lead to impaired self-defence against pathogens. Indeed, pregnant women are more susceptible to newly encountered viruses comparing to non-pregnant women, as exemplified by the prevalence of severe complications in pregnant women infected with the pandemic influenza virus in 2009. Plasmacytoid dendritic cells (pDCs) are specialized dendritic cells that recognise viral antigens and initiate both innate and adaptive immune responses. We therefore sought to determine whether the number and/or the functions of peripheral blood pDCs are regulated during pregnancy. pDC maturation and interferon (IFN)-α production were analysed in response to Toll-like receptor (TLR) stimulation of peripheral blood mononuclear cells from pregnant and non-pregnant women. Our results reveal that pDC frequency is slightly decreased, while the IFN-α production in response to TLR stimulation increases during pregnancy. Interestingly, the up-regulation of the co-stimulatory receptors CD54 (ICAM1) and CD86 is significantly decreased in pDCs from pregnant women as compared to controls, suggesting a possible impact on T-cell responses. In conclusion, we propose that the modulation of CD54 and CD86 expression on peripheral blood pDCs during pregnancy might decrease the initiation of adaptive antiviral immune responses.
authors.affiliation: Groupe de Recherche En Transplantation et Immunologie du Sang de Cordon (GRETISC), Centre de cancérologie Charles-Bruneau, Centre de recherche du CHU Sainte-Justine, Québec, Canada.
authors.forename: Martine
authors.initials: M
authors.lastname: Cordeau
authors.forename: Sabine
authors.initials: S
authors.lastname: Herblot
authors.forename: Emily
authors.initials: E
authors.lastname: Charrier
authors.forename: François
authors.initials: F
authors.lastname: Audibert
authors.forename: Paulo
authors.initials: P
authors.lastname: Cordeiro
authors.forename: Michaël
authors.initials: M
authors.lastname: Harnois
authors.forename: Michel
authors.initials: M
authors.lastname: Duval
mesh_terms: D000328:Adult; D051940:B7-2 Antigen / Q000276:immunology*; D003713:Dendritic Cells / Q000276:immunology*; D005260:Female; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000276:immunology*; D016898:Interferon-alpha / Q000276:immunology*; D008024:Ligands; D011247:Pregnancy / Q000276:immunology*; D011263:Pregnancy Trimester, Third / Q000276:immunology*; D011374:Progesterone / Q000097:blood; D051199:Toll-Like Receptor 7 / Q000276:immunology; D051217:Toll-Like Receptor 9 / Q000276:immunology; D015854:Up-Regulation
chemical_list: D051940:B7-2 Antigen; C497964:CD86 protein, human; D016898:Interferon-alpha; D008024:Ligands; C495348:TLR7 protein, human; C495371:TLR9 protein, human; D051199:Toll-Like Receptor 7; D051217:Toll-Like Receptor 9; D018799:Intercellular Adhesion Molecule-1; D011374:Progesterone