Design of liposomes for circumventing the reticuloendothelial cells.
Two different aspects of liposomal drug delivery to non-RES cells have been described. In one of the systems, by incorporating neutral glycolipids, with terminal beta-galactoside residue into liposomes, it is possible to target liposomes to the liver parenchymal cells, partially bypassing the RES. Asialoganglioside seems to be the most suited for this purpose. In another approach, various factors that prolong the lifespan of circulating liposomes have been discussed. It is possible to design such liposomes by imparting hydrophilicity to the liposomal surface. The effectiveness of a number of possible candidates, such as dextran, GM1 ganglioside and PEG, has been discussed in this context.