Transfection polysaccharides

The process by which cells take up large molecules is called endocytosis. Some of these molecules (eg, polysaccharides, proteins, and polynucleotides), when hydrolyzed inside the cell, yield nutrients. Endocytosis provides a mechanism for regulating the content of certain membrane components, hormone receptors being a case in point. Endocytosis can be used to learn more about how cells function. DNA from one cell type can be used to transfect a different cell and alter the latter s function or phenotype. A specific gene is often employed in these experiments, and this provides a unique way to smdy and analyze the regulation of that gene. DNA transfection depends upon endocytosis endocy-... 

Abstract Carbohydrates have been investigated and developed as delivery vehicles for shuttling nucleic acids into cells. In this review, we present the state of the art in carbohydrate-based polymeric vehicles for nucleic acid delivery, with the focus on the recent successes in preclinical models, both in vitro and in vivo. Polymeric scaffolds based on the natural polysaccharides chitosan, hyaluronan, pullulan, dextran, and schizophyllan each have unique properties and potential for modification, and these results are discussed with the focus on facile synthetic routes and favorable performance in biological systems. Many of these carbohydrates have been used to develop alternative types of biomaterials for nucleic acid delivery to typical polyplexes, and these novel materials are discussed. Also presented are polymeric vehicles that incorporate copolymerized carbohydrates into polymer backbones based on polyethylenimine and polylysine and their effect on transfection and biocompatibility. Unique scaffolds, such as clusters and polymers based on cyclodextrin (CD), are also discussed, with the focus on recent successes in vivo and in the clinic. These results are presented with the emphasis on the role of carbohydrate and charge on transfection. Use of carbohydrates as molecular recognition ligands for cell-type specific dehvery is also briefly... 

Keywords Carbohydrate DNA Nucleic acid delivery polysaccharide Transfection... 

Eliyahu H, Siani S, Azzam T et al (2006) Relationships between chemical composition, physical properties and transfection efficiency of polysaccharide-spermine conjugates. Biomaterials 27 1646-1655... 

Chitosan is a biodegradable polysaccharide and has been shown to interact with the phosphate groups of DNA, condensing plasmids into spherical and toroidal particles. The colloidal and surface properties of plasmid/chitosan complexes have been shown to depend on the molecular weight of chitosan, the ratio of plasmid to chitosan and the preparation medium. Smaller nanoparticles have been observed with low molecular weight chitosan (2 kDa) as compared to high molecular weight chitosan (540 kDa). A number of cell lines have been transfected with plasmid/chitosan complexes. 

Among cationic polymers, cationic polysaccharides secured an important position in this research area. Cationic polysaccharides most widely used for this purpose are chitosan, dextran, cyclodextrin (CD), pullulan and schizophyllan. These pol3aners act through the formation of an electrostatic complex, but they also create some problems like undesired interaction with blood components, low transfection efficiency and failure from endosomal escape, etc. Various modifications have been proposed to solve all these issues. 

Apart from polyplexes, various nanoscale assemblies of cationic polysaccharides are also proposed to promote the surface-mediated delivery of DNA to cells. These approaches are classified into one of two broad categories (i) methods based upon the physical adsorption of preformed polyplex on polymeric surfaces like PLGA or collagen films and these polyplex functionalized films promoted surface-mediated transfection of cells in vitro and in vivof (ii) methods for layer-by-layer adsorption of DNA and cationic polymers on surfaces to fabricate multilayered thin films. Recently, degradable carbohydrate-based nanogels were proposed for codelivery of pDNA and therapeutic proteins. These systems were designed to possess stimuli-sensitive characteristics where the temperature-sensitive property of nanogels allowed the facile encapsulation of biomaterials, while... 

Jo J, Okazaki A, Nagane K et al (2010) Preparation of cationized polysaccharides as gene transfection carrier for bone marrow-derived mesenchjnnal stem cells. J Biomater Sci Polym Ed 21 185-204. doi 10.1163/156856209X415495... 

Abstract Polysaccharides based nanomaterials have diverse applications in biomedical research. This chapter covers one of the major achievements in modification of polysaccharides using microwave irradiation and cationization methods. Additionally chapter focused on mucoadhesive polysaccharides and its recent advancement in nano drug delivery system. Applications such as gene transfection, bone regeneration and vaccine delivery are also separately discussed. 

Khan W, Hosseinkhani H, Ickowicz D, Hong PD, Yu DS, Dom AJ. Polysaccharide gene transfection agents. Acta Biomater. 2012 8 4224-32. 

Chitosan is another polymer that has been well characterized for use in transfection [49]. This natural nontoxic polysaccharide lends DNAase-resistance to its cargo while condensing the DNA to form stronger complexes [50]. The efficiency of chitosan is thought to rely upon its ability to swell and burst endolysosomes, which allows the delivered DNA to continue its path to the nucleus [51]. 

Thixotropy Property An aqueous solution of DEAE-dextran graft copolymer is with a thixotropy property as a non-Newtonian fluids, whose transfection solution is suflScient to flow and wet cells through a sheer stress for the solution in the transfection, such as swirling the pan distribute. A water-soluble polysaccharides and copolymers of vinyl coimection are interested for the wet-ability of the cells by the rheological properties[69]. Most reports in the rheological field were on the water-soluble polysaccharides and a few report deals with Graft polymerization of aerylamide (AM) on water-insoluble polysaeeharides such as cellulose [70]. 

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