000053707 001__ 53707
000053707 005__ 20181203015831.0
000053707 022__ $$a0022-538X
000053707 037__ $$aARTICLE
000053707 245__ $$aA third-generation lentivirus vector with a conditional packaging system
000053707 269__ $$a1998
000053707 260__ $$bAmerican Society for Microbiology$$c1998
000053707 336__ $$aJournal Articles
000053707 520__ $$aVectors derived from human immunodeficiency virus (HIV) are highly efficient vehicles for in vivo gene delivery. However, their biosafety is of major concern. Here we exploit the complexity of the HIV genome to provide lentivirus vectors with novel biosafety features. In addition to the structural genes, HIV contains two regulatory genes, tat and rev, that are essential for HIV replication, and four accessory genes that encode critical virulence factors. We previously reported that the HIV type 1 accessory open reading frames are dispensable for efficient gene transduction by a lentivirus vector. We now demonstrate that the requirement for the tat gene can be offset by placing constitutive promoters upstream of the vector transcript. Vectors generated from constructs containing such a chimeric long terminal repeat (LTR) transduced neurons in vivo at very high efficiency, whether or not they were produced in the presence of Tat. When the rev gene was also deleted from the packaging construct, expression of gag and pol was strictly dependent on Rev complementation in trans. By the combined use of a separate nonoverlapping Rev expression plasmid and a 5' LTR chimeric transfer construct, we achieved optimal yields of vector of high transducing efficiency (up to 10(7) transducing units [TU]/ml and 10(4) TU/ng of p24). This third-generation lentivirus vector uses only a fractional set of HIV genes: gag, pol, and rev. Moreover, the HIV-derived constructs, and any recombinant between them, are contingent on upstream elements and trans complementation for expression and thus are nonfunctional outside of the vector producer cells. This split-genome, conditional packaging system is based on existing viral sequences and acts as a built-in device against the generation of productive recombinants. While the actual biosafety of the vector will ultimately be proven in vivo, the improved design presented here should facilitate testing of lentivirus vectors.
000053707 6531_ $$aGenetic Vectors
000053707 700__ $$aDull, T.
000053707 700__ $$0240510$$aZufferey, R.$$g162095
000053707 700__ $$aKelly, M.
000053707 700__ $$aMandel, R. J.
000053707 700__ $$aNguyen, M.
000053707 700__ $$0240083$$aTrono, Didier$$g167919
000053707 700__ $$aNaldini, L.
000053707 773__ $$j72$$k11$$q8463-71$$tJ Virol
000053707 909C0 $$0252036$$pLVG$$xU11172
000053707 909C0 $$0252067$$pLEN$$xU10457
000053707 909CO $$ooai:infoscience.tind.io:53707$$pSV$$particle
000053707 917Z8 $$x182396
000053707 937__ $$aLVG-ARTICLE-1998-004
000053707 973__ $$aEPFL$$rREVIEWED$$sPUBLISHED
000053707 970__ $$a9765382/LVG
000053707 980__ $$aARTICLE