Mannosyl-coated nanocomplexes from amphiphilic cyclodextrins and pDNA for site-specific gene delivery

Abstract

Fully homogeneous facial amphiphiles consisting in a cyclodextrin (CD) platform onto which a polycationic cluster and a multi-tail hydrophobic moiety have been installed (polycationic amphiphilic CDs; paCDs) self-organized in the presence of plasmid DNA to form nanometric complexes (CDplexes) which exhibit broad-range transfection capabilities. We hypothesized that biorecognizable moieties located at the hydrophilic rim in the CD scaffold would be exposed at the surface of the corresponding nanoparticles after DNA-promoted aggregation, endowing the system with molecular recognition abilities towards cell receptors. This concept has been demonstrated by developing an efficient synthetic strategy for the preparation of multivalent polycationic glyco-amphiphilic CDs (pGaCDs). Self-assembled nanoparticles obtained from mannosylated pGaCDs and pDNA (average hydrodynamic diameter 80 nm) have been shown to be specifically recognized by mannose-specific lectins, including concanavalin A (Con A) and the human macrophage mannose receptor (MMR). Further macrophage adhesion studies indicated that unspecific binding, probably due to electrostatic interactions with negatively charged cell membrane components, can also operate. The relative specific versus non-specific internalization is dependent on the pGaCD:pDNA proportion, being optimal at a protonable nitrogen/phosphate (N/P) ratio of 5. The resulting GlycoCDplexes were shown to specifically mediate transfection in Raw 264.7 (murine macrophage) cells expressing the mannose-fucose receptor in vitro. FACS experiments confirmed that transfection using these nanoparticles is mannose-dependent, supporting the potential of the approach towards vectorized gene delivery.

Cyclodextrin-based multivalent glycodisplays: covalent and supramolecular conjugates to assess carbohydrate–protein interactions

“…Using this formulation, selective macrophage internalization was achieved as evidenced by fluorescent activated cell sorting (FACS), leading to macrophage-specific transfection. 167 Statistic incorporation of biorecognizable glycotopes onto a polycationic amphiphilic cyclodextrin (paCD) platform represents an alternative strategy to impart targeting abilities to molecular CD-based gene vectors. In principle, the pDNA complexing and lectin binding abilities could be optimized by varying the proportion of the coating sugar.…”

“…163 In the frame of a collaborative project aiming at developing CD-based molecular systems for site-specific gene delivery, García Fernández, Ortiz Mellet, Vierling and Defaye et al proposed a new multivalent vector prototype (108), characterized by incorporating (i) a cluster of alternated amino groups and glycosyl units at the primary rim of the bCD platform and (ii) a multitail hydrophobic domain at the secondary face (Scheme 44). 167 The synthesis followed a convergent scheme involving, as the key step, the multi-thiourea coupling reaction of an isothiocyanate-armed bifunctional dendritic element bearing an aMan residue and a Boc-protected amino group (106) with the per-(C-6)-cysteaminyl-per-(O-2,O-3)-hexanoyl bCD derivative 107. Final carbamate hydrolysis afforded the target C 7 -symmetric aMan-coated polycationic glycoamphiphilic CD (pGaCD) 108 in 70% yield.…”

Cyclodextrin-based star polymers as a versatile platform for nanochemotherapeutics: Enhanced entrapment and uptake of idarubicin

“…Polycationic amphiphilic CD derivative comprising a cationic cluster and multi-tail hydrophobic moiety was used as efficient vector for DNA [28]. Therefore, the ability of our particles to acquire a positive charge was verified.…”

Toward a magic or imaginary bullet? Ligands for drug targeting to cancer cells: principles, hopes, and challenges

“…128 Multivalent polycationic glyco-amphiphilic cyclodextrins were prepared and used for targeting the mannose receptor (MR) on macrophages. 129 Multibranched mannosylated lipids were prepared and incorporated into liposomes to allow for MR-mediated endocytosis by monocyte-derived dendritic cells. 125 Barrientos et al 130 have examined the interaction of lactose-functionalized gold nanoparticles (GNPs) with two different galactose-specific carbohydrate-binding proteins: an enzyme -β galactosidase from Escherichia coli and a lectin -the agglutinin from Viscum album.…”