title: Monoclonal antibody binding to the macrophage-specific receptor sialoadhesin alters the phagocytic properties of human and mouse macrophages.
abstract: Sialoadhesin (Sn) is a surface receptor expressed on macrophages in steady state conditions, but during inflammation, Sn can be upregulated both on macrophages and on circulating monocytes. It was shown for different species that Sn becomes internalized after binding with monoclonal antibodies. These features suggest that Sn is a potential target for immunotherapies. In this study, human and mouse macrophages were treated with anti-Sn monoclonal antibodies or F(ab')2fragments and the effect of their binding to Sn on phagocytosis was analyzed. Binding of antibodies to Sn resulted in delayed and reduced phagocytosis of fluorescent beads. No effect was observed on Fc-mediated phagocytosis or phagocytosis of bacteria by human macrophages. In contrast, an enhanced phagocytosis of bacteria by mouse macrophages was detected. These results showed that stimulation of Sn could have different effects on macrophage phagocytosis, depending both on the type of phagocytosis and cellular background.
authors.affiliation: Laboratory of Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp (UA), Antwerp 2610, Belgium. Electronic address: marjorie.deschryver@uantwerpen.be.
authors.forename: Marjorie
authors.initials: M
authors.lastname: De Schryver
authors.affiliation: Laboratory of Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp (UA), Antwerp 2610, Belgium. Electronic address: davie.cappoen@uantwerpen.be.
authors.forename: Davie
authors.initials: D
authors.lastname: Cappoen
authors.affiliation: Laboratory of Molecular Immunology and Inflammation, VIB Inflammation Research Center, Ghent University, Ghent 9052, Belgium; Department of Rheumatology, Ghent University Hospital, Ghent 9000, Belgium. Electronic address: dirk.elewaut@ugent.be.
authors.forename: Dirk
authors.initials: D
authors.lastname: Elewaut
authors.affiliation: Laboratory of Virology, Ghent University, Merelbeke 9820, Belgium. Electronic address: hans.nauwynck@ugent.be.
authors.forename: Hans J
authors.initials: HJ
authors.lastname: Nauwynck
authors.affiliation: Laboratory of Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp (UA), Antwerp 2610, Belgium. Electronic address: louis.maes@uantwerpen.be.
authors.forename: Louis
authors.initials: L
authors.lastname: Maes
authors.affiliation: Laboratory of Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp (UA), Antwerp 2610, Belgium. Electronic address: guy.caljon@uantwerpen.be.
authors.forename: Guy
authors.initials: G
authors.lastname: Caljon
authors.affiliation: Laboratory of Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp (UA), Antwerp 2610, Belgium. Electronic address: paul.cos@uantwerpen.be.
authors.forename: Paul
authors.initials: P
authors.lastname: Cos
authors.affiliation: Laboratory of Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp (UA), Antwerp 2610, Belgium. Electronic address: peter.delputte@uantwerpen.be.
authors.forename: Peter L
authors.initials: PL
authors.lastname: Delputte
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000494:pharmacology*; D002478:Cells, Cultured; D006801:Humans; D007249:Inflammation / Q000276:immunology*; D008264:Macrophages / Q000187:drug effects* / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D010587:Phagocytosis / Q000187:drug effects; D011485:Protein Binding / Q000187:drug effects; D063267:Sialic Acid Binding Ig-like Lectin 1 / Q000276:immunology / Q000378:metabolism*; D013045:Species Specificity
chemical_list: D000911:Antibodies, Monoclonal; D063267:Sialic Acid Binding Ig-like Lectin 1
keywords: Immunotherapy; Inflammation; Macrophages; Phagocytosis; Sialoadhesin/CD169/Siglec-1