title: Lipid mediator-induced expression of bactericidal/ permeability-increasing protein (BPI) in human mucosal epithelia.
abstract: Epithelial cells which line mucosal surfaces are the first line of defense against bacterial invasion and infection. Recent studies have also indicated that epithelial cells contribute significantly to the orchestration of ongoing inflammatory processes. Here, we demonstrate that human epithelial cells express bactericidal/permeability-increasing protein (BPI), an antibacterial and endotoxin-neutralizing molecule previously associated with neutrophils. Moreover, we demonstrate that such BPI expression is transcriptionally regulated by analogs of endogenously occurring anti-inflammatory eicosanoids (aspirin-triggered lipoxins, ATLa). Initial studies to verify microarray analysis revealed that epithelial cells of wide origin (oral, pulmonary, and gastrointestinal mucosa) express BPI and each is similarly regulated by aspirin-triggered lipoxins. Studies aimed at localization of BPI revealed that such expression occurs on the cell surface of cultured epithelial cell lines and dominantly localizes to epithelia in human mucosal tissue. Functional studies employing a BPI-neutralizing anti-serum revealed that surface BPI blocks endotoxin-mediated signaling in epithelia and kills Salmonella typhimurium. These studies identify a previously unappreciated "molecular shield" for protection of mucosal surfaces against Gram-negative bacteria and their endotoxin.
authors.affiliation: Department of Veterinary Physiology, University College of Dublin, Dublin 4, Ireland.
authors.forename: Geraldine
authors.initials: G
authors.lastname: Canny
authors.forename: Ofer
authors.initials: O
authors.lastname: Levy
authors.forename: Glenn T
authors.initials: GT
authors.lastname: Furuta
authors.forename: Sailaja
authors.initials: S
authors.lastname: Narravula-Alipati
authors.forename: Richard B
authors.initials: RB
authors.lastname: Sisson
authors.forename: Charles N
authors.initials: CN
authors.lastname: Serhan
authors.forename: Sean P
authors.initials: SP
authors.lastname: Colgan
mesh_terms: D000900:Anti-Bacterial Agents / Q000378:metabolism* / Q000494:pharmacology; D000893:Anti-Inflammatory Agents / Q000378:metabolism / Q000494:pharmacology; D023181:Antimicrobial Cationic Peptides; D001798:Blood Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D018938:Caco-2 Cells; D002460:Cell Line; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D004847:Epithelial Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects*; D006801:Humans; D007249:Inflammation / Q000378:metabolism / Q000382:microbiology / Q000473:pathology; D008055:Lipids / Q000494:pharmacology*; D008070:Lipopolysaccharides / Q000037:antagonists & inhibitors / Q000378:metabolism / Q000494:pharmacology; D008565:Membrane Proteins; D009092:Mucous Membrane / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*; D021381:Protein Transport; D012486:Salmonella typhimurium / Q000502:physiology
chemical_list: D000900:Anti-Bacterial Agents; D000893:Anti-Inflammatory Agents; D023181:Antimicrobial Cationic Peptides; D001798:Blood Proteins; D008055:Lipids; D008070:Lipopolysaccharides; D008565:Membrane Proteins; C021623:bactericidal permeability increasing protein