Types Of Viral Vectors
2nd generation lentiviral vector
The second-generation three-plasmid expression system is to separate the cis-acting sequence structure and the sequence encoding the trans-acting protein required for packaging, reverse transcription and integration in the HIV-1 genome, and then clone them into three independent plasmids Among them, one is a packaging plasmid, which contains the CMV promoter, which controls the expression of all viral structural genes except env, and the second is an envelope plasmid, which contains the sequence of the vesicular stomatitis virus glycoprotein (VSV-G) gene, This gene is used to replace the env gene of the original virus. The product of this gene can increase the host range of the virus, and the other is a vector plasmid, which contains the sequence structure of the gene that researchers are interested in. However, this three-plasmid system still retains the accessory genes of HIV-1. This plasmid system is more likely to have an active virus due to accidents, so it is considered to have a lower safety factor, but because of its higher potency for virus production , More suitable for research use.