Unlike transfecting cells with foreign DNA or RNA, virus transfection does not require transfection reagents. The viral vector itself, also known as the virion, can infect cells and transport DNA directly to the nucleus, regardless of other functions. After the DNA is released into the nucleus, the cell's own mechanism is used to produce the target protein.
Typical transduction protocols include the engineering of recombinant viruses carrying transgenes, amplification of recombinant virus particles in packaging cell lines, purification and titration of amplified virus particles, and subsequent infection of target cells. Although the transduction efficiency achieved in primary cells and cell lines is high (about 90-100%), only cells with virus-specific receptors can be infected by the virus. It is also important to note that packaging cell lines used for viral amplification need to be transfected with non-viral transfection methods.
