title: The recognition of adsorbed and denatured proteins of different topographies by beta2 integrins and effects on leukocyte adhesion and activation.
abstract: Leukocyte beta2 integrins Mac-1 and p150,95 are promiscuous cell-surface receptors that recognise and mediate cell adhesion to a variety of adsorbed and denatured proteins. We used albumin as a model protein to study whether leukocyte adhesion and activation depended on the nm-scale topography of a protein adlayer. Albumin adsorbed from the native conformation gave rise to different adlayer topographies and different amounts of adsorbed protein on hydrophobic and relatively hydrophilic polystyrene and silanised silicon-wafer surfaces, whereas adsorption of pre-denatured Alb resulted in similar adlayer topographies and similar amounts of adsorbed protein on these surfaces. All three distinct protein-adlayer topographies supported adhesion of in vitro differentiated, macrophage-like U937 and THP-1 cells, but did not support adhesion of their promonocytic precursors. Human monocytes freshly isolated from peripheral blood did not adhere to adsorbed albumin, not even in the presence of monocyte chemoattractant protein-1 and macrophage inflammatory protein-1alpha chemokines. Adhesion of the macrophage-like cells to albumin in any of the three topographies was inhibited by antibodies against beta2 integrins, but not by antibodies against beta1 integrins, and did not induce secretion of the proinflammatory cytokine tumour necrosis factor-alpha.
authors.affiliation: Bioneer A/S, Mammalian Cell Biology, Kogle Allé 2, DK-2970 Hørsholm, Denmark. tbr@bioneer.dk
authors.forename: Thomas
authors.initials: T
authors.lastname: Brevig
authors.forename: Bjørn
authors.initials: B
authors.lastname: Holst
authors.forename: Zahida
authors.initials: Z
authors.lastname: Ademovic
authors.forename: Noemi
authors.initials: N
authors.lastname: Rozlosnik
authors.forename: Jette H
authors.initials: JH
authors.lastname: Røhrmann
authors.forename: Niels B
authors.initials: NB
authors.lastname: Larsen
authors.forename: Ole C
authors.initials: OC
authors.lastname: Hansen
authors.forename: Peter
authors.initials: P
authors.lastname: Kingshott
mesh_terms: D000327:Adsorption; D000418:Albumins / Q000737:chemistry / Q000378:metabolism; D017209:Apoptosis; D001672:Biocompatible Materials / Q000737:chemistry*; D018821:CD18 Antigens / Q000737:chemistry*; D002448:Cell Adhesion; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D054407:Chemokine CCL4; D016207:Cytokines / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004492:Edetic Acid / Q000494:pharmacology; D006801:Humans; D007249:Inflammation; D007962:Leukocytes / Q000166:cytology*; D019402:Macrophage Inflammatory Proteins / Q000378:metabolism; D008264:Macrophages / Q000378:metabolism; D018625:Microscopy, Atomic Force; D009000:Monocytes / Q000378:metabolism; D011137:Polystyrenes / Q000737:chemistry; D011487:Protein Conformation; D011489:Protein Denaturation; D011506:Proteins / Q000737:chemistry; D012825:Silicon / Q000737:chemistry; D013052:Spectrometry, X-Ray Emission / Q000379:methods; D013499:Surface Properties; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D020298:U937 Cells
chemical_list: D000418:Albumins; D001672:Biocompatible Materials; D018821:CD18 Antigens; D054407:Chemokine CCL4; D016207:Cytokines; D019402:Macrophage Inflammatory Proteins; D011137:Polystyrenes; D011506:Proteins; D014409:Tumor Necrosis Factor-alpha; D004492:Edetic Acid; D012825:Silicon