Liposome-Mediated DNA Transfer

Abstract

The DNA-mediated transfer of genes has been used extensively as a tool for genetic study of both prokaryotic and eukaryotic cells. For those cells for which DNA transformation systems have been developed, gene transfer has yielded a wealth of detail for bacterial (Avery et al., 1944), yeast (Hinnen et al., 1978), and animal cell (McBride and Athwall, 1977; Wigler et al., 1977) molecular biology. A variety of techniques have been used to effect the introduction of relatively unpurified nucleic acids into eukaryotic cells, including cell: cell fusion (Ringertz and Savage, 1976) and uptake of isolated nuclei, microcells (Fournier and Ruddle, 1977), bacterial protoplasts (Schaffner, 1980), viruses (Hamer et al., 1979; Mulligan et al., 1979), or whole chromosomes (McBride and Athwall, 1977) by cells. Purified nucleic acids can be introduced into cells as calcium phosphate coprecipitates (Graham and Van der Eb, 1973) or polycation complexes (McCutchen and Pagano, 1968), which may be endocytosed. In addition, cryoprotectants and polyalcohols (Hinnen et al., 1978; Stow and Wilkie, 1976) also facilitate nucleic acid uptake. Direct introduction of genetic material into cells can be accomplished by microinjection with small capillary needles (Capecchi, 1980; Anderson et al., 1980) or by prepackaging the nucleic acid in carriers such as liposomes (phospholipid vesicles*) or red blood cell ghosts (Straus and Raskas, 1980). While specific successes have been attained by all the methods mentioned, this chapter will deal with the methods, advantages, and potential of liposomes as carriers of nucleic acids.