Transfection is generally defined as the process of introducing DNA, RNA or proteins into cells to influence their genotype or phenotype. This includes introducing new genes to study or leverage their function, as well as using other constructs to indirectly influence endogenous gene expression or other cellular processes. Although less common, protein transfection is also used, either to generate a more rapid response or to facilitate certain applications (for example, CRISPR for genome editing).
Transfection has many applications. Besides basic research, these include gene therapy, immunotherapy and induced pluripotent stem cell generation. Meanwhile, recombinant protein expression also enables a wide range of functional, genetic mapping and biochemical characterization studies, in addition to bioproduction applications. Different types of cells can be transfected (such as primary cells, cell lines, and stem cells), making this a powerful tool for use across the life sciences.
Choosing the most effective transfection method for your application and cell type is important, as transfection efficiency, cell viability and expression levels can vary between each. Common approaches include transfection of different substrates (e.g. DNA, RNA, or protein) using one of various transfection methods, like lipofection, electroporation, calcium phosphate transfection, liposome transfection, and viral transduction, as well as physical methods such as microinjection and biolistic particle delivery. Further development of electroporation by legacy Amaxa has led to the development of a more efficient transfection technology called Nucleofection.
Before choosing a transfection method, it is important to consider what substrate to transfect and whether you wish to achieve transient or stable transfection. Below, we outline the difference between stable and transient transfection and discuss the different transfection substrates you might use. We also describe in more detail the transfection methods that are currently available, including their respective benefits, drawbacks and ideal applications. This information will help you select the best transfection processes and reagents for your needs. You can also download our free transfection methods guide for more information.