INTERPOLYELECTROLYTE COMPLEXES OF NUCLEIC -ACIDS AS A MEANS FOR TARGETED DELIVERY OF GENETIC MATERIAL TO THE CELL

The prospects of using interpolyelectrolyte complexes (IPEC) of DNA wi th polycations to deliver genetic material to the cell are reviewed. I PEC are formed in solutions of DNA and polycation due to a cooperative system of interchain electrostatic bonds. Physicochemical characteris tics of IPEC, including solubility and the size and the surface charge of IPEC particles are controlled by IPEC composition, which is descri bed as the polycation: DNA ratio expressed in base-mole units of each component. Incorporation into IPEC significantly affects the propertie s of DNA; it becomes more compact and stable to cleavage by nucleases. Transformation of B. subtilis is used to illustrate the incorporation of plasmid into IPEC with carbochain polycation, which significantly enhances the transforming activity. These IPEC can bind to animal cell s and exhibit endocytosis. An effective procedure for transfection of animal cells is reported, which involves incorporation of plasmid DNA into complexes with carbochain polycations and lipopolyamines. IPEC-ba sed structures are also used to deliver DNA via a receptor-mediated pa thway. For this purpose, the molecule of polycation [poly(L-lysine)] t hat enters into the complex is covalently bound to the ligand; this en sures endocytosis of IPEC and transfection of the cells. A similar app roach was used for targeted delivery of genetic material to the target cells in the body. In this case, the polycation combines with antibod ies or other molecules that can selectively interact with the target.