Use of Cat-Anionic Vesicles as Molecular Vectors for Gene Transfer into Target Cells

Abstract

We report on the possibilities to use cat-anionic vesicles as active vectors for transfection technologies. Cat-anionic aggregates are non-stoichiometric mixtures made of oppositely charged surfactants, or lipids. Depending on the relative amounts of two such components, bi- or multi-layered vesicles may be formed. The former ones adsorb bio-polymers on their outer surface, but bi-layers may also contain large amounts of lipophilic species in their interior. The transfection fate depends on the vesicle ability and efficiency in adsorption, which leads, eventually, to fusion with cell membranes. The intra-membrane uptake mechanisms differ significantly, and depend on whether the outer, inner, or bi-layer distribution of the species is considered. The first possibility involves a direct exchange of (supra) molecular entities between fluid surfaces in contact; the second and third, conversely, imply membrane fusion and subsequent transport of material within the cell matrix. A realistic combination of the above possibilities can be envisaged, and would ensure a long term action of the transferred (transfected) formulations. Examples taken from recent literature suggest that a realistic possibility is offered to high-yield molecular penetration: this becomes useful in gene transfer and molecular transfection technologies. Some technological aspects inherent to the above formulations are briefly outlined. The overall effect of penetration across the cell membrane of exogenous material in terms of biocompatibility is quite a formidable task to face with and shall be described in detail.