title: The influence of net surface charge on the interaction of uropathogenic Escherichia coli with human neutrophils.
abstract: Escherichia coli strains, grown to suppress fimbrial expression, synthesised enhanced quantities of polysaccharide capsule, which significantly lessened their binding to heparin sepharose columns. In the presence of poly-L-lysine, these strains were strongly retained on the columns confirming their highly anionic nature. Uropathogenic strains of E. coli expressing type 1 fimbrial adhesins activated the respiratory burst, the degranulation response and the release of leukotrienes from human neutrophils (PMN) to a significantly greater extent than the same strains grown in a medium to suppress this fimbrial expression. The addition of the poly-cation poly-L-lysine, however, selectively increased neutrophil activation in response to these non-fimbriate strains. This dose-dependent effect was reversed by the addition of heparin suggesting a mechanism dependent on surface charge. The results of this study suggest that non-specific mechanisms involving the neutralisation of surface charge, in addition to specific receptor and adhesin mediated events could affect neutrophil activation at sites of infection.
authors.affiliation: Institute of Nephrology, University of Wales College of Medicine, Cardiff Royal Infirmary, U.K.
authors.forename: R
authors.initials: R
authors.lastname: Steadman
authors.forename: J
authors.initials: J
authors.lastname: Knowlden
authors.forename: M
authors.initials: M
authors.lastname: Lichodziejewska
authors.forename: J
authors.initials: J
authors.lastname: Williams
mesh_terms: D002462:Cell Membrane / Q000502:physiology; D004563:Electrochemistry; D004926:Escherichia coli / Q000502:physiology*; D010861:Fimbriae, Bacterial / Q000502:physiology; D006801:Humans; D007975:Leukotriene B4 / Q000378:metabolism; D008163:Luminescent Measurements; D008247:Lysosomes / Q000201:enzymology; D009504:Neutrophils / Q000382:microbiology* / Q000502:physiology; D009195:Peroxidase / Q000378:metabolism; D011107:Polylysine / Q000494:pharmacology; D014155:Transcobalamins / Q000378:metabolism
chemical_list: D014155:Transcobalamins; D007975:Leukotriene B4; D011107:Polylysine; D009195:Peroxidase