A general approach to the non-invasive imaging of transgenes using cis-linked herpes simplex virus thymidine kinase.
Non-invasive imaging of gene expression opens new prospects for the study of transgenic animals and the implementation of genetically based therapies in patients. We have sought to establish a general paradigm to enable whole body non-invasive imaging of any transgene. We show that the expression and imaging of HSV1-tk (a marker gene) can be used to monitor the expression of the LacZ gene (a second gene) under the transcriptional control of a single promoter within a bicistronic unit that includes a type II internal ribosomal entry site. In cells bearing a single copy of the vector, the expression of the two genes is proportional and constant, both in vitro and in vivo. We demonstrate that non-invasive imaging of HSV1-tk gene accurately reflects the topology and activity of the other cis-linked transgene.
Department of Neurology, Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA.
J G
JG
Tjuvajev
A
A
Joshi
J
J
Callegari
L
L
Lindsley
R
R
Joshi
J
J
Balatoni
R
R
Finn
S M
SM
Larson
M
M
Sadelain
R G
RG
Blasberg
D000818:Animals; D015139:Blotting, Southern; D003952:Diagnostic Imaging / Q000379:methods*; D004926:Escherichia coli / Q000201:enzymology; D005720:Gamma Rays; D015316:Genetic Therapy / Q000379:methods; D005822:Genetic Vectors; D007763:Lac Operon / Q000235:genetics; D009368:Neoplasm Transplantation; D011401:Promoter Regions, Genetic; D051381:Rats; D017207:Rats, Sprague-Dawley; D012190:Retroviridae / Q000235:genetics; D018139:Simplexvirus / Q000201:enzymology*; D013937:Thymidine Kinase / Q000235:genetics*; D014158:Transcription, Genetic; D014161:Transduction, Genetic; D019076:Transgenes; D014407:Tumor Cells, Cultured; D001616:beta-Galactosidase / Q000378:metabolism
D013937:Thymidine Kinase; D001616:beta-Galactosidase