title: Beta amyloid precursor protein mediates neuronal cell-cell and cell-surface adhesion.
abstract: The beta-amyloid precursor protein (APP) is a membrane-bound glycoprotein which has been proposed to play a role both as a growth factor and a mediator of cell adhesion. Using the Neuro-2A neuroblastoma cell line, we have investigated the capacity of APP to mediate neural cell adhesion. The cells express the protein at a high level, the immunohistochemical staining pattern at the level of the membrane having a punctate pattern. Fab' fragments of antibodies to the extracellular portion of the molecule were found to inhibit cell binding to a collagen substrate, but not to laminin, fibronectin, or poly-l-lysine. Fab' fragments of antibodies to the nerve cell adhesion molecule N-CAM also inhibited binding of Neuro-2A cells specifically to collagen. This inhibition of cell-surface binding was accompanied by a repression of neurite outgrowth in differentiating cells in the presence of antibodies. APP antibodies also inhibited neuron-neuron and neuron-glial binding, but not glial-glial cell adhesion. These data suggest that the APP, which is expressed primarily on differentiated neuronal cells, may play a role in the mediation of both cell-cell and cell-substrate adhesion.
authors.affiliation: Department of Cellular and Molecular Sciences, St. Georges Hospital Medical School, London, England.
authors.forename: K C
authors.initials: KC
authors.lastname: Breen
authors.forename: M
authors.initials: M
authors.lastname: Bruce
authors.forename: B H
authors.initials: BH
authors.lastname: Anderton
mesh_terms: D016229:Amyloid beta-Peptides / Q000502:physiology*; D016564:Amyloid beta-Protein Precursor; D000818:Animals; D001369:Axons / Q000648:ultrastructure; D003994:Bucladesine / Q000494:pharmacology; D002448:Cell Adhesion; D015816:Cell Adhesion Molecules, Neuronal / Q000502:physiology*; D002454:Cell Differentiation / Q000187:drug effects; D002460:Cell Line; D002531:Cerebellum / Q000166:cytology; D016326:Extracellular Matrix Proteins / Q000378:metabolism; D005347:Fibroblasts / Q000166:cytology; D007140:Immunoglobulin Fab Fragments / Q000494:pharmacology; D051379:Mice; D009447:Neuroblastoma / Q000473:pathology; D009457:Neuroglia / Q000166:cytology; D009474:Neurons / Q000166:cytology* / Q000648:ultrastructure; D011480:Protease Inhibitors / Q000378:metabolism; D011485:Protein Binding; D011498:Protein Precursors / Q000502:physiology*; D051381:Rats; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000473:pathology
chemical_list: D016229:Amyloid beta-Peptides; D016564:Amyloid beta-Protein Precursor; D015816:Cell Adhesion Molecules, Neuronal; D016326:Extracellular Matrix Proteins; D007140:Immunoglobulin Fab Fragments; D011480:Protease Inhibitors; D011498:Protein Precursors; D003994:Bucladesine