D GIPZ lentiviral control vectors were also obtained from Thermo Scientific. To generate nonreplicating lentivirus stocks, lentiviral gene silencing constructs were cotransfected with pMD2.G and psPAX2 vectors (Addgene plasmid 12259 and Addgene plasmid 12260, respectively; deposited by Dr. Didier Trono) into packaging HEK 293-T cells. Cell supernatants containing nonreplicating lentiviral vectors