Authors: E.H. Chowdhury and T. Akaike
Affilation: Tokyo Institute of Technology, Japan
Pages: 284 - 287
Keywords: Ca-Mg phosphate, gene delivery, nano-crystal
Significant efforts are now being made for the development of non-viral gene-delivery techniques as alternatives to the viral vectors for basic research and clinical medicine. Despite existence of a wide variety of non-viral techniques particularly relying on synthetic lipids (liposomes), peptides (poly-L-lysine), dendrimers (polyamidoamine) and other polymers, such as polyethylenimine, limited understanding of the molecular and cellular basis in gene transfer hinders the development of a smart technology. Co-precipitation of DNA with calcium phosphate which is based on hydroxyapatite, is one of the most commonly used non-viral vectors. Although inefficiency in particle-mediated uptake of DNA by the cells has been considered as a major barrier of low transgene expression in vitro and in vivo an effective way of manipulating particle growth kinetics at the molecular level has not been focused so far, which could overcome the hurdle dramatically. Here, we report here on the development of a highly efficient synthetic device for gene delivery and expression into mammalian cells, based on controllable growth of nano-apatite particles. Mg2+ incorporation into the apatite particles caused significant inhibition of particle-growth (Fig. 1), resulting in retention of nano-sized particles (Fig. 2) which could contribute remarkably to the cellular uptake of DNA (not showing here) and its subsequent expression (at last 10-fold) compared with classical calcium phosphate co-precipitation (Fig. 3), one of the most widely used transfection methods. Thus, this innovative technology is a tool of utmost importance in bioresearch laboratories, biotech companies for production of recombinant cell lines and finally for gene therapy.