title: Cellular uptake of gold nanoparticles bearing HIV gp120 oligomannosides.
abstract: Dendritic cells are the most potent of the professional antigen-presenting cells which display a pivotal role in the generation and regulation of adaptive immune responses against HIV-1. The migratory nature of dendritic cells is subverted by HIV-1 to gain access to lymph nodes where viral replication occurs. Dendritic cells express several calcium-dependent C-type lectin receptors including dendritic cell-specific ICAM-3 grabbing non-integrin (DC-SIGN), which constitute a major receptor for HIV-1. DC-SIGN recognizes N-linked high-mannose glycan clusters on HIV gp120 through multivalent and Ca(2+)-dependent protein-carbohydrate interactions. Therefore, mimicking the cluster presentation of oligomannosides from the virus surface is a strategic approach for carbohydrate-based microbicides. We have shown that gold nanoparticles (mannoGNPs) displaying multiple copies of structural motifs (di-, tri-, tetra-, penta-, or heptaoligomanosides) of the N-linked high-mannose glycan of viral gp120 are efficient inhibitors of DC-SIGN-mediated trans-infection of human T cells. We have now prepared the corresponding fluorescent-labeled glyconanoparticles (FITC-mannoGNPs) and studied their uptake by DC-SIGN expressing Burkitt lymphoma cells (Raji DC-SIGN cell line) and monocyte-derived immature dendritic cells (iDCs) by flow cytometry and confocal laser scanning microscopy. We demonstrate that the 1.8 nm oligomannoside coated nanoparticles are endocytosed following both DC-SIGN-dependent and -independent pathways and part of them colocalize with DC-SIGN in early endosomes. The blocking and sequestration of DC-SIGN receptors by mannoGNPs could explain their ability to inhibit HIV-1 trans-infection of human T cells in vitro.
authors.affiliation: Laboratory of Glyconanotechnology, Biofunctional Nanomaterials Unit, CIC biomaGUNE, P° de Miramón 182, 20009 San Sebastian, Spain.
authors.forename: Blanca
authors.initials: B
authors.lastname: Arnáiz
authors.forename: Olga
authors.initials: O
authors.lastname: Martínez-Ávila
authors.forename: Juan M
authors.initials: JM
authors.lastname: Falcon-Perez
authors.forename: Soledad
authors.initials: S
authors.lastname: Penadés
mesh_terms: D015815:Cell Adhesion Molecules / Q000378:metabolism; D002460:Cell Line; D003713:Dendritic Cells / Q000166:cytology / Q000378:metabolism; D016650:Fluorescein-5-isothiocyanate / Q000737:chemistry; D006046:Gold / Q000737:chemistry*; D015699:HIV Envelope Protein gp120 / Q000737:chemistry*; D015497:HIV-1; D006801:Humans; D042541:Intracellular Space / Q000378:metabolism; D007700:Kinetics; D037181:Lectins, C-Type / Q000378:metabolism; D053768:Metal Nanoparticles / Q000737:chemistry*; D009844:Oligosaccharides / Q000737:chemistry* / Q000378:metabolism*; D021381:Protein Transport; D011956:Receptors, Cell Surface / Q000378:metabolism; D000099215:DC-Specific ICAM-3 Grabbing Nonintegrin
chemical_list: D015815:Cell Adhesion Molecules; D016650:Fluorescein-5-isothiocyanate; D006046:Gold; D015699:HIV Envelope Protein gp120; D037181:Lectins, C-Type; D009844:Oligosaccharides; D011956:Receptors, Cell Surface; D000099215:DC-Specific ICAM-3 Grabbing Nonintegrin; C514793:gp120 protein, Human immunodeficiency virus 1; C028569:oligomannoside