title: Intercellular adhesion molecule 3, a candidate human immunodeficiency virus type 1 co-receptor on lymphoid and monocytoid cells.
abstract: The CD4 molecule serves as the principal cell surface receptor common to both the human and simian immunodeficiency viruses (HIV-1, HIV-2 and SIV). Since binding to CD4 is not sufficient to permit virus entry, HIV 'co-receptors' have been implicated in mediating the fusion of viral and cellular membranes necessary for completing the entry process. In order to identify candidate co-receptor molecules, a panel of monoclonal antibodies (MAbs) directed against adhesion molecules was tested for the ability of the MAbs to inhibit HIV-1-induced cell fusion (syncytium formation) and HIV-1 entry. Certain antibodies directed against CD18, CD11b and CD11c inhibited HIV-1-induced syncytium formation but not entry, in agreement with previous reports. Interestingly, certain antibodies to ICAM-3 (intercellular adhesion molecule 3) (CD50) significantly inhibited HIV-1-specific entry but not syncytium formation using human SupT1 cells. Only one antibody directed against ICAM-3 significantly inhibited HIV-1-induced syncytium formation, entry and infectivity. Our results suggest that certain epitopes of ICAM-3 may be involved in mediating HIV-1-specific entry into lymphoid and monocytoid cells.
authors.affiliation: Centre for Research in Virology, University of Bergen, Bergen High Technology Centre, Norway.
authors.forename: M A
authors.initials: MA
authors.lastname: Sommerfelt
authors.forename: B
authors.initials: B
authors.lastname: Asjö
mesh_terms: D000911:Antibodies, Monoclonal / Q000494:pharmacology; D000918:Antibody Specificity; D015703:Antigens, CD; D000943:Antigens, Differentiation; D015704:CD4 Antigens / Q000502:physiology; D015815:Cell Adhesion Molecules / Q000276:immunology / Q000502:physiology*; D002460:Cell Line; D015726:Giant Cells / Q000276:immunology; D054303:HIV Reverse Transcriptase; D015497:HIV-1 / Q000502:physiology*; D006367:HeLa Cells; D006801:Humans; D008214:Lymphocytes / Q000276:immunology / Q000821:virology*; D008561:Membrane Fusion; D009000:Monocytes / Q000276:immunology / Q000821:virology*; D012194:RNA-Directed DNA Polymerase / Q000032:analysis; D011991:Receptors, Virus / Q000502:physiology*; D014721:Vesicular stomatitis Indiana virus / Q000502:physiology
chemical_list: D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D000943:Antigens, Differentiation; D015704:CD4 Antigens; D015815:Cell Adhesion Molecules; C483616:ICAM3 protein, human; D011991:Receptors, Virus; D054303:HIV Reverse Transcriptase; D012194:RNA-Directed DNA Polymerase