Transfection of Mammalian cells in vitro: use in analysis of neuronal damage

Transfection of specific elements of DNA into cultured mammalian cells allows for the analysis of a range of functional and toxicologic mechanisms. At the heart of this technique is the ability to promote the uptake of DNA into actively growing cells, and to detect and analyze the expression of the gene(s) encoded by the DNA (1). The two basic types of transfection analyses are transient transfections, in which the DNA is expressed during the few days postapplication, and stable transfections, in which cells expressing the gene of interest are actively selected via cointroduction of a marker for positive selections (2). Choosing which technique is appropriate for a given experiment is determined by the temporal aspects of the question, the types of assays performed, and whether the gene of interest is expressed constitutively or via an inducible promoter. Illustrations for both methods will be provided.