title: Cellular inflammatory response to persistent localized Staphylococcus aureus infection: phenotypical and functional characterization of polymorphonuclear neutrophils (PMN).
abstract: Persistent, localized Staphylococcus aureus infections, refractory to antibiotic treatment, can result in massive tissue destruction and surgical intervention is often the only therapeutic option. In that context, we investigated patients with S. aureus-induced infection at various sites, apparent as either olecranon bursitis, empyema of the knee joint or soft tissue abscess formation. As expected, a prominent leucocyte infiltrate was found, consisting predominantly of polymorphonuclear neutrophils (PMN) (up to 75%) and to a lesser extent of T lymphocytes and natural killer (NK) cells. In line with their bactericidal capacity, PMN expressed the high-affinity receptor for IgG, CD64 and the lipopolysaccharide (LPS) receptor CD14; moreover, the oxygen radical production in response to the bacterial peptide f-MLP was enhanced, while chemotactic activity was greatly reduced. The more intriguing finding, however, was that a portion of PMN had acquired major histocompatibility complex (MHC) class II antigens and CD83, indicative of a transdifferentiation of PMN to cells with dendritic-like characteristics. Of note is that a similar transdifferentiation can be induced in PMN in vitro, e.g. by gamma interferon or by tumour necrosis factor alpha. Co-cultivation of transdifferentiated PMN with autologous T lymphocytes resulted in prominent T cell proliferation, provided that S. aureus enterotoxin A was added. Taken together, persistent S. aureus infection induces PMN to acquire characteristics of dendritic cells, which in turn might promote the local immune response.
authors.affiliation: Klinik für Unfall- und Wiederherstellungschirurgie, Berufsgenossenschaftliche Unfallklinik Ludwigshafen, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Wagner
authors.forename: C
authors.initials: C
authors.lastname: Iking-Konert
authors.forename: F
authors.initials: F
authors.lastname: Hug
authors.forename: S
authors.initials: S
authors.lastname: Stegmaier
authors.forename: V
authors.initials: V
authors.lastname: Heppert
authors.forename: A
authors.initials: A
authors.lastname: Wentzensen
authors.forename: G M
authors.initials: GM
authors.lastname: Hänsch
mesh_terms: D000368:Aged; D000938:Antigen-Presenting Cells / Q000276:immunology; D002454:Cell Differentiation; D049109:Cell Proliferation; D002469:Cell Separation; D002634:Chemotaxis, Leukocyte; D005260:Female; D005434:Flow Cytometry; D000949:Histocompatibility Antigens Class II / Q000032:analysis; D006801:Humans; D018950:Lipopolysaccharide Receptors / Q000032:analysis; D008213:Lymphocyte Activation; D008297:Male; D008875:Middle Aged; D009504:Neutrophils / Q000276:immunology*; D017464:Receptors, Complement 3d / Q000032:analysis; D017452:Receptors, IgG / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013203:Staphylococcal Infections / Q000276:immunology*; D013481:Superoxides / Q000378:metabolism; D013601:T-Lymphocytes / Q000166:cytology
chemical_list: D000949:Histocompatibility Antigens Class II; D018950:Lipopolysaccharide Receptors; D017464:Receptors, Complement 3d; D017452:Receptors, IgG; D013481:Superoxides