PET reporter genes for noninvasive imaging of gene therapy, cell tracking and transgenic analysis.

Department of Biological Chemistry, Molecular Biology Institute, Crump Institute for Molecular Imaging, David Geffen School of Medicine at UCLA, 341 Boyer Hall, 611 Charles E. Young Drive East, Los Angeles, CA 90095, USA.
Critical Reviews in Oncology/Hematology (Impact Factor: 4.05). 10/2004; 51(3):191-204. DOI: 10.1016/j.critrevonc.2004.04.006
Source: PubMed

ABSTRACT Positron-emission tomography (PET) has been used extensively in the clinic for cancer diagnosis, for staging and for monitoring of therapeutic efficacy. PET has not, however, been used extensively in contemporary animal cancer models. Until recently, appropriate instrumentation was not available and the expertise and knowledge necessary to perform PET analyses in murine models has not been widespread. The fabrication of microPET instruments with appropriate resolution for murine experiments has lead to the establishment of non-invasive techniques for functional imaging. The development of "PET reporter genes" whose activity can be monitored in living animals, based on the reporter gene-dependent sequestration of positron-emitting "PET reporter probes," has lead to innovative analyses of gene expression in transgenic animals, to methods to monitor the location, magnitude and duration of expression for gene therapy vectors and to the ability to non-invasively track the targeting, viability and expansion of cellular therapeutics.

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    • "SPECT gathers imaging information based on the amount of gamma-emitting radionucleotides that emit a single photon, but it is generally not as sensitive and less quantifiable than PET. PET detects biochemical processes in cells by measuring the positrons emitted by the probe as it decays and collides with electrons in vivo (Doubrovin et al. 2004, Herschman 2004). The PET emissions are two photons released 180° from one another and detected in an array, which measure the volume and concentration of the probe (Blasberg 2002). "
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