Renato Ribeiro-Viana

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Ligand polyvalency is a powerful modulator of protein-receptor interactions. Host-pathogen infection interactions are often mediated by glycan ligand-protein interactions, yet its interrogation with very high copy number ligands has been limited to heterogenous systems. Here we report that through the use of nested layers of multivalency we are able to(More)
BACKGROUND The involvement of the complement system in brain injury has been scarcely investigated. Here, we document the pivotal role of mannose-binding lectin (MBL), one of the recognition molecules of the lectin complement pathway, in brain ischemic injury. METHODS AND RESULTS Focal cerebral ischemia was induced in mice (by permanent or transient(More)
DC-SIGN is a C-type lectin receptor on antigen presenting cells (dendritic cells) which has an important role in some viral infection, notably by HIV and Dengue virus (DV). Multivalent presentation of carbohydrates on dendrimeric scaffolds has been shown to inhibit DC-SIGN binding to HIV envelope glycoprotein gp120, thus blocking viral entry. This approach(More)
Water-soluble glycofullerenes based on a hexakis-adduct of [60]fullerene with an octahedral addition pattern are very attractive compounds providing a spherical presentation of carbohydrates. These tools have been recently described and they have been used to interact with lectins in a multivalent manner. Here, we present the use of these glycofullerenes,(More)
In genital mucosa, different fates are described for HIV according to the subtype of dendritic cells (DCs) involved in its recognition. This notably depends on the C-type lectin receptor, langerin or DC-SIGN, involved in gp120 interaction. Langerin blocks HIV transmission by its internalization in specific organelles of Langerhans cells. On the contrary,(More)
Vaccination strategies based on dendritic cells (DCs) armed with specific tumor antigens have been widely exploited due the properties of these immune cells in coordinating an innate and adaptive response. Here, we describe the convergent synthesis of the bifunctional multivalent glycodendron 5, which contains nine residues of mannose for DC targeting and(More)
Glycodendrons bearing nine copies of mannoses or fucoses have been prepared by an efficient convergent strategy based on Cu(I) catalyzed azide-alkyne cycloaddition (CuAAC). These glycodendrons present a well-defined structure and have an adequate size and shape to interact efficiently with the C-type lectin DC-SIGN. We have selected a BODIPY derivative to(More)
The C-type lectin DC-SIGN expressed on immature dendritic cells is a promising target for antiviral drug development. Previously, we have demonstrated that mono- and divalent C-glycosides based on d-manno and l-fuco configurations are promising DC-SIGN ligands. Here, we described the convergent synthesis of C-glycoside dendrimers decorated with 4, 6, 9, and(More)
Glycofullerenes, in which carbohydrate molecules are attached via a linker to a [60]fullerene core, facilitate spherical presentation of glyco-based epitopes. We herein investigate the dynamics of two glycofullerenes, having 12 and 36 mannose residues at their periphery, by NMR translational diffusion and quantitative (13)C relaxation studies employing a(More)
DC-SIGN (dendritic cell-specific ICAM-3 grabbing non-integrin) is a C-type lectin receptor (CLR) present, mainly in dendritic cells (DCs), as one of the major pattern recognition receptors (PRRs). This receptor has a relevant role in viral infection processes. Recent approaches aiming to block DC-SIGN have been presented as attractive anti-HIV strategies.(More)