title: Bacterial adhesion, intracellular survival and cytokine induction upon stimulation of mononuclear cells with planktonic or biofilm phase Staphylococcus epidermidis.
abstract: Staphylococcus epidermidis is a leading cause of hospital-acquired and biofilm-associated infections. Interactions of peripheral blood mononuclear cells (PBMCs) and monocyte-derived macrophages with planktonic or biofilm phase S. epidermidis cells were studied. Biofilm phase bacteria exhibited higher attachment, as well as, a 10-fold higher intracellular survival in monocyte-derived macrophages than their planktonic counterparts. Stimulation of PBMCs and monocyte-derived macrophages was performed with live or formalin-fixed bacterial cells. Supernatant concentration of selected cytokines was measured by Luminex(®)  xMAP(™)  technology at different time points. As compared to planktonic phase, biofilm phase bacteria elicited lower amounts of proinflammatory cytokines and Th1 response cytokines, such as TNFα, IL-12p40, IL-12p70 and IFN-γ, whereas they enhanced production of IL-8, GM-CSF and IL-13. This phenomenon was independent of formalin pretreatment. Taken together, these results may contribute to interpretation of observed silent course of biofilm-associated infections.
authors.affiliation: Department of Microbiology, School of Medicine, University of Patras, Patras, Greece.
authors.forename: Anastasia I
authors.initials: AI
authors.lastname: Spiliopoulou
authors.forename: Fevronia
authors.initials: F
authors.lastname: Kolonitsiou
authors.forename: Maria I
authors.initials: MI
authors.lastname: Krevvata
authors.forename: Michalis
authors.initials: M
authors.lastname: Leontsinidis
authors.forename: Thomas S
authors.initials: TS
authors.lastname: Wilkinson
authors.forename: Dietrich
authors.initials: D
authors.lastname: Mack
authors.forename: Evangelos D
authors.initials: ED
authors.lastname: Anastassiou
mesh_terms: D001422:Bacterial Adhesion; D018441:Biofilms / Q000254:growth & development*; D002478:Cells, Cultured; D016207:Cytokines / Q000378:metabolism*; D006805:Human Experimentation; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000276:immunology / Q000382:microbiology*; D050296:Microbial Viability; D013212:Staphylococcus epidermidis / Q000276:immunology / Q000472:pathogenicity / Q000502:physiology*
chemical_list: D016207:Cytokines