...Can be packaged ONLY by a second generation packaging system that includes TAT Can be packaged by both...plasmid such as psPAX2 . 3rd generation packaging systems: express gag and pol from one packaging plasmid and...destination vector (in this case the destination vector would be the lentiviral transfer vector). The destination...envelope, and packaging components of the virus onto different vectors. The transfer vector encodes the ...the envelope and packaging vectors. Unless recombination occurs between the packaging, envelope, and transfer...SIN) after integration. Packaging plasmid(s) Envelope plasmid Addgene’s packaging and envelope plasmids ...transfer plasmid can be packaged by either a 2nd generation or 3rd generation packaging system. For a comparison...