Transfection vectors

Besides exploring DQAsomes as a mitochondrial transfection vector, we also have been working on utilizing DQAsomes as amitochondiia-targeted carrier... 

Lynn DM, Anderson DG, Putnam D, Langer R (2001) Accelerated discovery of synthetic transfection vectors parallel synthesis and screening of a degradable polymer library. J Am Chem Soc 123 8155-8156... 

The principal advantage of COS cell transient cDNA expression systems is that they provide a rapid means for producing catalytically active protein. The introduction of the cDNA into the vector is simple, based on rapid bacteria-based molecular biology. The vector DNA is then used to directly transfect the host cells. COS cell expression suffers from limitations in expression level (which tends to be low) and overall yield, since a limited number of cells can be transfected and only about 10% of the cells take up the transfected vector molecule. The practical aspects of COS cell expression are discussed in Clarke and Waterman (1991). 

Abstract In the late 1980s independent work by Feigner and Behr pioneered the use of cationic materials to complex and deliver nucleic acids into eukaryotic cells. Since this time, a vast number of synthetic transfection vectors, which are typically divided into two main transfectors , have been developed namely (1) cationic lipids and (2) polycationic polymers. In this chapter the main synthetic approaches used for the synthesis of these compounds will be reviewed with particular attention paid to cationic lipids and dendrimers. This review is aimed primarily at the younger audience of doctoral students and non-specialist readers. 

The search for an efficient and non-toxic gene transfection vector has led to the design and synthesis of a great variety of macromolecular scaffolds. An extensive analysis of the key features for the efficient and safe delivery of genes in vivo and in vitro has led to the conclusion that hyperbranched polymers are potential candidates for further development. In this chapter we have presented a detailed analysis of the different hyperbranched polymer scaffolds commonly used in gene delivery applications. Several structural modifications toward the development of an optimal gene vector have been analyzed. 

Recently, studies performed in DMSO revealed that it is crucial to remove traces of both carbon dioxide and water in the crosslinking of PEI with DSP. In addition, the DSP adding rate as well as its amount is important for the preparation of low toxicity and high efficiency gene transfection vectors [141], Super-expandable nanogels that undergo nano- to microscale volume transition in response to... 

Functionalized GNPs with branched 2 kDa polyethyleneimine (PEI) for transfection vectors The transfection efficiency into monkey kidney (Cos-7) cells varied with the PEIrgold molar ratio in the conjugates. The study indicates that increasing the hydrophobicity of the transfection agent enhances cellular intemalizatirai. Positively chaiged synthetic materials are widely used as transfection vectors Klibanov et al. [63]... 

A major drawback of current transfection vectors is that they have poor in vivo transfection efficiency and only confer transient gene expression. Indeed, poor transfection efficiency is due, in part, to the lack of stability of the non-viral vector-DNA complex under physiological conditions and its ability to interact with blood plasma proteins after intravenous injection, the extracellular matrix, and undesirable cells, and its possible degradation by enzymes, even before reaching the intracellular compartment (Scheme 12). In order to overcome these problems and to enable the carrier to translocate across cellular membranes (thus... 

Kubasiak LA, Tomalia DA (2005) Cationic dendiimcas as gene transfection vectors dtaidri-poly(amidoamines) and dendri-poly(propylenimines). In Amiji MM (ed) Polymeric gene delivery-principles and applications. CRC, Boca Raton, pp 133-157... 

When oxidized (-1-3), the ferrocenium-containing BFDMA cationic lipids were poor transfection vectors for plasmid DNA in simian kidney (COS-7) cells (Figure 12). Quantitative studies with luciferase showed that transfection with the oxidized vector occurred best at 20 pM, while higher and lower concentrations showed little to no activity, making them considerably less effective than either of the commercially available delivery agents Lipofectamine or TransIT-LTl. Cytotoxicity studies with this oxidized compound showed <20% cell death for all concentrations, but this increased drastically when incubation time with cells was increased past 4 h (over 50% cell death for concentrations of 40 and... 

Viral vector is one of the important transfection vector systems, which used as an effective way of DNA delivery and efficient target cell- specific transfection. In fact, viral vector based gene therapy involves 75% of recent clinical protocols. However, except few, no definitive success has been credited for the clinical effectiveness of viral system [136, 137]. Moreover, toxicity, restricted targeting of specific cell types, limited DNA carrying capacity, production and packaging problems, and high cost limits the application of viral medicated delivery system [138-141]. 

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