Lentivirus-Mediated Transfection Models

Lentiviral transgenesis is known as a method of using lentivectors to generate transgenic animals through the transduction of embryonic stem (ES) cells or early embryos. Lentiviruses are capable of integrating the transgene of interest into the host chromosome and ensuring stable expression. Largely because of its high efficiency, lentiviral transgenesis is an attractive alternative to the classical pronuclear injection of DNA. At Creative Biolabs, we offer this traditional but efficient technology to produce transgenic animal models for various research applications.

Introduction of Lentiviral Vectors

Lentiviruses are members of the Retroviridae family. Lentiviral vectors have proven to be potent gene delivery vehicles that enable stable expression of transgenes into a broad spectrum of cells and tissues, including non-dividing cells and stem cells. The typical lentiviral vector system is based on separate vector and packaging constructs. The vector carries the transgene of interest, while the packaging plasmids provide the viral proteins required for packaging. To address important safety concerns like insertional activation of cellular oncogenes, self-inactivating (SIN) vectors have been designed in which the viral enhancer and promoter sequences within the LTRs have been deleted. Therefore, during vector design process, promoters have to be incorporated in SIN vector constructs to drive transgene expression in the target cells. Generally, ubiquitously expressing promoters or specific promoters can be incorporated for different research purposes.

Principles of Lentiviral Transgenesis

The key to lentiviral transgenesis is to infect single-cell embryo with lentiviral particles by microinjecting the high titer viral solution into the space between the plasma membrane of the embryo and the zona pellucida. Therefore, three principles of successful lentiviral transgenesis are design and generation of the optimal lentiviral vector, production of high titer lentivirus, and skillful manipulation of microinjection.

Features of Lentiviral Transgenesis

Lentivirus-mediated transgenesis allows the production of a large number of transgenic animals containing a single-copy transgene. Transgenic animals can be obtained from a single experiment due to its high efficiency.
Unlike the recombinant Moloney murine leukemia virus vectors, the gene expression from lentiviral vectors does not get silenced during the development of the transgenic animal.
Lentiviral transgenesis has been shown to be highly effective in many different species, including mouse, rat, pig, bovine, and even birds, thereby having the potential to become a versatile and widespread transgenic technology.
Lentiviral vectors expressing small hairpin RNAs are widely used to downregulate specific target genes, acting as a method of RNA interference.
Despite its enormous potential, lentiviral transgenesis is a specialized technique that needs sufficient experience to make it work.