Calcium Phosphate Transfection of Mammalian Cultured Cells

Calcium phosphate and DEAE-dextran reagents were incorporated into the first chemical methods that successfully transferred nucleic acid directly to cultured mammalian cells in a process referred to as transfection (1 –4 ). Early transfection studies used viral RNA (1 ) and DNA (2 ,4 ), which, at that time, were relatively easy to propagate and purify, and allowed phenotypic discrimination of the transfected mammalian cells. Calcium phosphate coprecipitation and DEAE-dextran methods became widely used after cloning and manipulation of plasmid DNA became routine, and it was demonstrated that plasmid DNA was effectively transferred to cultured cells using these methods. Together with advancements in vector development came the introduction of additional transfection methods using chemical reagents such as liposomes (5 ,6 ), dendrimers (7 ,8 ), and cationic polymers (9 ,10 ), plus physical methods such as electroporation (11 ) and biolistic microparticle bombardment (12 ). However, the calcium phosphate coprecipitation technique still remains one of the most widely used in vitro transfection methods.