title: Butanol-extracted lipoteichoic acid induces in vivo leukocyte adhesion.
abstract: Lipoteichoic acid (LTA), an immunostimulatory component of the cell walls of gram positive bacteria, has pro-inflammatory effects in vitro and in vivo. However, one in vivo study concluded that LTA had no noticeable effects on leukocyte recruitment. In this study we investigated the effects of highly purified LTA, prepared by butanol extraction (Bu-LTA) at room temperature, on in vivo leukocyte adhesion. Using intravital microscopy we measured adhesion of leukocytes in mesenteric post-capillary venules of rats and mice. Topical superfusion of Bu-LTA (1 microg/ml) in rats significantly (p<0.05) increased adhesion within 30 min. By contrast, hot phenol-extracted LTA did not increase adhesion. Alkaline hydrolysis of Bu-LTA removed alanine residues and prevented adhesion. Also, pre-administration of anti-rat beta2-integrin antibody abolished Bu-LTA-induced adhesion. Finally, intraperitoneal injection of Bu-LTA (100 microg/ml) into mice also significantly (p<0.01) increased leukocyte adhesion measured at 60 min. In conclusion, Bu-LTA with intact alanine residues promotes beta2-integrin-dependent leukocyte adhesion in vivo.
authors.affiliation: Unit of Critical Care, National Heart and Lung Institute, Faculty of Medicine, Imperial College London, Dovehouse Street, London, SW3 6LY, United Kingdom. s.finney@imperial.ac.uk
authors.forename: Simon J
authors.initials: SJ
authors.lastname: Finney
authors.forename: Peter B
authors.initials: PB
authors.lastname: Anning
authors.forename: Thong V
authors.initials: TV
authors.lastname: Cao
authors.forename: Mauro
authors.initials: M
authors.lastname: Perretti
authors.forename: Timothy W
authors.initials: TW
authors.lastname: Evans
authors.forename: Anne
authors.initials: A
authors.lastname: Burke-Gaffney
mesh_terms: D000818:Animals; D000440:Butanols / Q000737:chemistry*; D002448:Cell Adhesion / Q000187:drug effects / Q000502:physiology; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D007962:Leukocytes / Q000166:cytology* / Q000187:drug effects / Q000502:physiology*; D008070:Lipopolysaccharides / Q000008:administration & dosage* / Q000302:isolation & purification*; D051379:Mice; D051381:Rats; D013211:Staphylococcus aureus / Q000378:metabolism*; D013682:Teichoic Acids / Q000008:administration & dosage* / Q000302:isolation & purification*
chemical_list: D000440:Butanols; D008070:Lipopolysaccharides; D013682:Teichoic Acids; C009900:lipoteichoic acid