title: Aquaphilus dolomiae extract counteracts the effects of cutaneous S. aureus secretome isolated from atopic children on CD4+T cell activation.
abstract: BACKGROUND
  Skin microbiota takes part in the control of cutaneous inflammation. In skin diseases such as atopic dermatitis (AD) cutaneous dysbiosis and the emergence of Staphylococcus aureus contribute to the pathophysiology of the disease. New therapeutic approaches consist in topical application of natural products able to counteract S. aureus effects through activation of resident immune cells producing anti-inflammatory cytokines such as IL-10.
  
  
  OBJECTIVE
  This study investigates the potential immunosuppressive properties of Aquaphilus dolomiae (Neisseriaceae), a flagellated bacterium contained in Avène Thermal Spring Water used in hydrotherapy treatments of AD patients.
  
  
  METHODS
  An aqueous protein extract of Aquaphilus dolomiae (ADE, 60 μg/mL) was added to human monocyte-derived dendritic cells (moDC) for 24 h. Expression of HLA-DR, CD86 and CD83 was evaluated by flow cytometry and released cytokines (IL-10, IL-12) by cytometry bead array assay. The proliferation of allogeneic CFSE-labelled CD4+T cells stimulated with ADE-conditioned moDC and S. aureus secretome was analysed by flow cytometry.
  
  
  RESULTS
  MoDC exposed to ADE expressed lower levels of HLA-DR and CD86 than untreated cells, no CD83 and secreted barely detectable IL-12 but high amounts of IL-10 (N = 12, p < 0.0002). The proliferative effect of S. aureus secretome on CD4+T cells was reduced (p < 0.001) in the presence of ADE-moDC.
  
  
  CONCLUSIONS
  ADE counteracted the mitogenic effect of a S. aureus secretome on CD4+T cells. Owing to the role of S. aureus colonization in driving inflammation in AD the immunosuppressive property of the ADE might be useful to reduce disease severity.
authors.affiliation: a INSERM UMR 1043, CNRS UMR 5282, Université Toulouse III Paul Sabatier , Toulouse , France.
authors.forename: Hélène
authors.initials: H
authors.lastname: Martin
authors.affiliation: a INSERM UMR 1043, CNRS UMR 5282, Université Toulouse III Paul Sabatier , Toulouse , France.
authors.forename: Emeline
authors.initials: E
authors.lastname: Laborel-Préneron
authors.affiliation: a INSERM UMR 1043, CNRS UMR 5282, Université Toulouse III Paul Sabatier , Toulouse , France.
authors.forename: Frédérique
authors.initials: F
authors.lastname: Fraysse
authors.affiliation: b Dermo-Cosmétique , Pierre Fabre , Toulouse , France.
authors.forename: Thien
authors.initials: T
authors.lastname: Nguyen
authors.affiliation: b Dermo-Cosmétique , Pierre Fabre , Toulouse , France.
authors.forename: Anne-Marie
authors.initials: AM
authors.lastname: Schmitt
authors.affiliation: b Dermo-Cosmétique , Pierre Fabre , Toulouse , France.
authors.forename: Daniel
authors.initials: D
authors.lastname: Redoulès
authors.affiliation: a INSERM UMR 1043, CNRS UMR 5282, Université Toulouse III Paul Sabatier , Toulouse , France.
authors.forename: Christian
authors.initials: C
authors.lastname: Davrinche
mesh_terms: D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D002648:Child; D003876:Dermatitis, Atopic / Q000188:drug therapy* / Q000382:microbiology; D006801:Humans; D007166:Immunosuppressive Agents / Q000494:pharmacology*; D016753:Interleukin-10 / Q000096:biosynthesis; D008213:Lymphocyte Activation; D009346:Neisseriaceae; D012867:Skin / Q000382:microbiology*; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000276:immunology
chemical_list: D007166:Immunosuppressive Agents; D016753:Interleukin-10
keywords: Dendritic cells; IL-10; lymphocyte proliferation; skin microbiota