title: Antibacterial effect of microvesicles released from human neutrophilic granulocytes.
abstract: Cell-derived vesicles represent a recently discovered mechanism for intercellular communication. We investigated their potential role in interaction of microbes with host organisms. We provide evidence that different stimuli induced isolated neutrophilic granulocytes to release microvesicles with different biologic properties. Only opsonized particles initiated the formation of microvesicles that were able to impair bacterial growth. The antibacterial effect of neutrophil-derived microvesicles was independent of production of toxic oxygen metabolites and opsonization or engulfment of the microbes, but depended on β(2) integrin function, continuous actin remodeling, and on the glucose supply. Neutrophil-derived microvesicles were detected in the serum of healthy donors, and their number was significantly increased in the serum of bacteremic patients. We propose a new extracellular mechanism to restrict bacterial growth and dissemination.
authors.affiliation: Department of Physiology, Semmelweis University, Budapest, Hungary.
authors.forename: Csaba I
authors.initials: CI
authors.lastname: Timár
authors.forename: Akos M
authors.initials: AM
authors.lastname: Lorincz
authors.forename: Roland
authors.initials: R
authors.lastname: Csépányi-Kömi
authors.forename: Anna
authors.initials: A
authors.lastname: Vályi-Nagy
authors.forename: György
authors.initials: G
authors.lastname: Nagy
authors.forename: Edit I
authors.initials: EI
authors.lastname: Buzás
authors.forename: Zsolt
authors.initials: Z
authors.lastname: Iványi
authors.forename: Agnes
authors.initials: A
authors.lastname: Kittel
authors.forename: David W
authors.initials: DW
authors.lastname: Powell
authors.forename: Kenneth R
authors.initials: KR
authors.lastname: McLeish
authors.forename: Erzsébet
authors.initials: E
authors.lastname: Ligeti
mesh_terms: D000328:Adult; D016470:Bacteremia / Q000097:blood / Q000276:immunology*; D055252:Cell-Derived Microparticles / Q000276:immunology* / Q000382:microbiology; D054377:Chemokine CXCL12 / Q000494:pharmacology; D002630:Chemotactic Factors / Q000494:pharmacology; D022162:Cytoplasmic Vesicles / Q000187:drug effects / Q000276:immunology*; D003599:Cytoskeleton / Q000502:physiology; D006801:Humans; D008070:Lipopolysaccharides / Q000494:pharmacology; D009504:Neutrophils / Q000276:immunology* / Q000382:microbiology* / Q000648:ultrastructure; D009895:Opsonin Proteins / Q000276:immunology / Q000378:metabolism*; D013203:Staphylococcal Infections / Q000276:immunology; D013211:Staphylococcus aureus / Q000254:growth & development / Q000276:immunology
chemical_list: C515255:CXCL12 protein, human; D054377:Chemokine CXCL12; D002630:Chemotactic Factors; D008070:Lipopolysaccharides; D009895:Opsonin Proteins