Ray P, Gambhir SSNoninvasive imaging of molecular events with bioluminescent reporter genes in living subjects. Methods Mol Biol 411: 131-144

Molecular Imaging Program at Stanford, Department of Radiology, Bio-X Program, Stanford University, USA.
Methods in Molecular Biology (Impact Factor: 1.29). 02/2007; 411:131-44. DOI: 10.1007/978-1-59745-549-7_10
Source: PubMed


Bioluminescence imaging has become a very popular tool for noninvasive monitoring of fundamental biological and molecular processes in small living subjects. Luciferases are light-emitting enzymes that can generate light (known as bioluminescence) after reacting with specific substrates. The emitted light is used as a detection system for luciferase activity, which acts as a "reporter" for the activity of any regulatory elements that control its expression. These enzymes are isolated from various organisms, conveniently modified for expression in mammalian cells, and are extensively used in molecular biology and cell culture experiments. Recent advances in optical technology have opened a new dimension for in vivo application of luciferase enzymes in biomedical research. The most commonly utilized luciferases for in vivo bioluminescence are isolated from two very different sources: firefly luciferase (or beetle luciferase) and renilla luciferase (isolated from sea pansy). Although both these luciferases can produce light following interaction with the substrates, structurally and biochemically they are very different. Here we describe the methods and applications of firefly and renilla luciferases in molecular imaging using small animals.

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Article: Ray P, Gambhir SSNoninvasive imaging of molecular events with bioluminescent reporter genes in living subjects. Methods Mol Biol 411: 131-144

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    • "A region of interest of constant shape and size (0.53 cm2) was drawn over the transfected hindlimbs of all animals. Bioluminescence signal in the region of interest was quantified using the maximum radiance measured in photons/sec/cm2/steradian (sr) 31. "
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    • "In support of this, several groups have utilized optical, magnetic, or nuclear imaging techniques to evaluate gene transfer in animal models. In optical imaging studies, genes inducing fluorescence or bioluminescence have been used very successfully in mouse models [1, 2]. However, these approaches are limited for human studies due to low tissue penetration and high scattering of the fluorescent or bioluminescent signal, and potential immunogenicity of the fluorescent or luminescent proteins. "
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