Linked Life Data

15152187

Source:http://linkedlifedata.com/resource/pubmed/id/15152187

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
13
pubmed:dateCreated
2004-6-23
pubmed:abstractText
Vectors suitable for delivery of therapeutic genes to the CNS for chronic neurodegenerative diseases will require regulatable transgene expression. In this study, three self-regulating rAAV vectors encoding humanized green fluorescent protein (hGFP) were made using the tetracycline (tet)-off system. Elements were cloned in different orientations relative to each other and to the AAV internal terminal repeat (ITRs). The advantage of this vector system is that all infected cells will carry both the 'therapeutic' gene and the tet-regulator. To compare the efficiency of the vectors, 293T cells infected by each vector were grown in the presence or absence of the tet-analog doxycycline (dox). Cells were analyzed by flow cytometry for hGFP protein expression, and quantitative RT-PCR (QRT-PCR) for levels of hGFP mRNA and the tet-activator (tTA) mRNA. In the presence of dox, cells infected with one of the vectors, rAAVS3, showed less than 2% total fluorescent intensity and mRNA copy number than cells grown without dox. The other two vectors were significantly more leaky. Levels of tTA mRNA were not affected by dox. The S3 vector also displayed tight regulation in HeLa and HT1080 cells. To assess regulation in the brain, the S3 vector was injected into rat striatum and rats maintained on regular or dox-supplemented water. At 1 month after vector injection, numerous positive cells were observed in rats maintained on regular water whereas only rare positive cells with very low levels of fluorescence were observed in rats maintained on water containing dox. The QRT-PCR analysis showed that dox inhibited expression of hGFP mRNA in brain by greater than 99%. These results demonstrate that exceedingly tight regulation of transgene expression is possible using the tet-off system in the context of a self-regulating rAAV vector and that the specific orientation of two promoters relative to each other and to the ITRs is important. Regulatable vectors based on this design are ideal for therapeutic gene delivery to the CNS.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0969-7128
pubmed:author
pubmed:issnType
Print
pubmed:volume
11
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1057-67
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:15152187-Animals, pubmed-meshheading:15152187-Cell Line, pubmed-meshheading:15152187-Central Nervous System, pubmed-meshheading:15152187-Dependovirus, pubmed-meshheading:15152187-Doxycycline, pubmed-meshheading:15152187-Flow Cytometry, pubmed-meshheading:15152187-Gene Expression, pubmed-meshheading:15152187-Gene Expression Regulation, pubmed-meshheading:15152187-Gene Therapy, pubmed-meshheading:15152187-Genetic Vectors, pubmed-meshheading:15152187-Green Fluorescent Proteins, pubmed-meshheading:15152187-HeLa Cells, pubmed-meshheading:15152187-Humans, pubmed-meshheading:15152187-Luminescent Proteins, pubmed-meshheading:15152187-Neurodegenerative Diseases, pubmed-meshheading:15152187-RNA, Messenger, pubmed-meshheading:15152187-Rats, pubmed-meshheading:15152187-Rats, Inbred F344, pubmed-meshheading:15152187-Recombinant Proteins, pubmed-meshheading:15152187-Reverse Transcriptase Polymerase Chain Reaction, pubmed-meshheading:15152187-Tetracycline, pubmed-meshheading:15152187-Transgenes
pubmed:year
2004
pubmed:articleTitle
Tight regulation from a single tet-off rAAV vector as demonstrated by flow cytometry and quantitative, real-time PCR.
pubmed:affiliation
1Department of Pediatrics, Children's Memorial Institute for Education & Research, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't