title: Plasmacytoid dendritic cells and CD8 T cells from pregnant women show altered phenotype and function following H1N1/09 infection.
abstract: BACKGROUND
  Pregnant women are a high-risk group during influenza pandemics. In this study we determined whether plasmacytoid dendritic cells (pDCs) and CD8 T cells from pregnant women display altered activity following in vitro infection with 2009 pandemic swine influenza (H1N1/09).
  
  
  METHODS
  Peripheral blood mononuclear cells (PBMCs) were isolated from pregnant (n = 26) and nonpregnant (n = 28) women. DC subtypes were enumerated from PBMCs. PBMCs were infected with H1N1/09 and CD86, human leukocyte antigen-DR (HLA-DR), and programmed death ligand 1/2 (PDL1/2) measured on pDCs. PD receptor 1 (PD1) was measured on CD8 T cells. Interferon-alpha (IFN-α), interleukin-2 (IL-2), tumor necrosis factor-alpha (TNFα), and IFN-gamma were measured from culture supernatant.
  
  
  RESULTS
  pDC (ie, CD303(+)/CD1c(-) PBMCs) percentages were lower in pregnant compared with nonpregnant women (P < .05). Following H1N1/09 infection, pDCs from pregnant women showed higher expression of CD86 (P < .01), HLA-DR (P < .001), and PDL1 (P < .001) compared with nonpregnant women. Expression of PD1 on CD8 T cells was higher during pregnancy (P < .05). Following H1N1/09 infection, PBMCs from pregnant women displayed reduced IFN-α (P < .01), IL-2 (P < .01), and IFN-γ (P < .01) compared with nonpregnant women. Blocking PDL1 during H1N1/09 infection increased these cytokines during pregnancy (P < .05).
  
  
  CONCLUSIONS
  Altered maternal cellular antiviral activity is implicated in the increased morbidity during pregnancy following influenza pandemics.
authors.affiliation: Centre for Asthma and Respiratory Diseases, School of Medicine and Public Health, The University of Newcastle Newcastle, Australia. rebecca.vanders@newcastle.edu.au
authors.forename: Rebecca L
authors.initials: RL
authors.lastname: Vanders
authors.forename: Peter G
authors.initials: PG
authors.lastname: Gibson
authors.forename: Vanessa E
authors.initials: VE
authors.lastname: Murphy
authors.forename: Peter A B
authors.initials: PA
authors.lastname: Wark
mesh_terms: D000328:Adult; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D002478:Cells, Cultured; D016207:Cytokines / Q000378:metabolism; D003713:Dendritic Cells / Q000276:immunology*; D005260:Female; D006801:Humans; D016130:Immunophenotyping; D053118:Influenza A Virus, H1N1 Subtype / Q000276:immunology*; D007251:Influenza, Human / Q000276:immunology* / Q000821:virology*; D007963:Leukocytes, Mononuclear / Q000276:immunology; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000276:immunology* / Q000821:virology*; D037841:Pregnant People
chemical_list: D016207:Cytokines
keywords: CD8 T cell; CD86; H1N1/09; HLA-DR; IFN; PD1; PDL1; PDL2; pDCs; pregnancy