title: Lectin KM+-induced neutrophil haptotaxis involves binding to laminin.
abstract: The lectin KM+ from Artocarpus integrifolia, also known as artocarpin, induces neutrophil migration by haptotaxis. The interactions of KM+ with both the extracellular matrix (ECM) and neutrophils depend on the lectin ability to recognize mannose-containing glycans. Here, we report the binding of KM+ to laminin and demonstrate that this interaction potentiates the KM+-induced neutrophil migration. Labeling of lung tissue by KM+ located its ligands on the endothelial cells, in the basement membrane, in the alveolus, and in the interstitial connective tissue. Such labeling was inhibited by 400 mM D-mannose, 10 mM Manalpha1-3[Manalpha1-6]Man or 10 microM peroxidase (a glycoprotein-containing mannosyl heptasaccharide). Laminin is a tissue ligand for KM+, since both KM+ and anti-laminin antibodies not only reacted with the same high molecular mass components of a lung extract, but also determined colocalized labeling in basement membranes of the lung tissue. The relevance of the KM+-laminin interaction to the KM+ property of inducing neutrophil migration was evaluated. The inability of low concentrations of soluble KM+ to induce human neutrophil migration was reversed by coating the microchamber filter with laminin. So, the interaction of KM+ with laminin promotes the formation of a substrate-bound KM+ gradient that is able to induce neutrophil haptotaxis.
authors.affiliation: Departamento de Biologia Celular e Molecular e Bioagentes Patogênicos, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes 3900, 14049-900, Ribeirão Preto, SP, Brazil.
authors.forename: Luciane
authors.initials: L
authors.lastname: Ganiko
authors.forename: Antônio R
authors.initials: AR
authors.lastname: Martins
authors.forename: Edna
authors.initials: E
authors.lastname: Freymüller
authors.forename: Renato A
authors.initials: RA
authors.lastname: Mortara
authors.forename: Maria-Cristina
authors.initials: MC
authors.lastname: Roque-Barreira
mesh_terms: D000818:Animals; D001485:Basement Membrane / Q000378:metabolism; D001665:Binding Sites; D002634:Chemotaxis, Leukocyte / Q000187:drug effects*; D006801:Humans; D007797:Laminin / Q000378:metabolism*; D008024:Ligands; D008168:Lung / Q000378:metabolism; D037241:Mannose-Binding Lectins / Q000378:metabolism / Q000494:pharmacology*; D009504:Neutrophils / Q000187:drug effects* / Q000276:immunology; D037121:Plant Lectins / Q000378:metabolism / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D007797:Laminin; D008024:Ligands; D037241:Mannose-Binding Lectins; D037121:Plant Lectins; C090683:artocarpin lectin