Stable transfection is a technique used to introduce foreign DNA into the genome of a eukaryotic cell in order to achieve long-term, stable expression of a transgene. This technique is commonly used in molecular biology and biotechnology research to study gene function or to produce recombinant proteins for therapeutic or commercial purposes.
The process of stable transfection involves introducing the foreign DNA into the host cell using a vector, which is a DNA molecule that is capable of replicating in the host cell and carrying the foreign DNA into the nucleus. The most commonly used vectors for stable transfection are plasmids, which are circular pieces of DNA that can be easily manipulated and propagated in bacteria.
After the vector is introduced into the host cell, the cells are typically subjected to a selection process in order to identify those cells that have incorporated the foreign DNA into their genome. The selection process usually involves the use of antibiotics or other selective agents that kill or inhibit the growth of cells that do not have the foreign DNA integrated into their genome.
Once the stable transfection cells are isolated, they can be expanded and used for downstream applications, such as protein expression, gene function studies, or drug screening. The advantage of stable transfection over transient transfection is that stable transfection cells can maintain long-term expression of the transgene, whereas transiently transfected cells only express the transgene for a limited time. However, stable transfection requires more time and effort to establish and can be subject to positional effects, which can affect the level and stability of gene expression.