Imaging cyclooxygenase-2 (Cox-2) gene expression in living animals with a luciferase knock-in reporter gene.
The cyclooxygenase-2 (Cox-2) gene plays a role in a variety of normal and pathophysiological conditions. Expression of the Cox-2 gene is induced in a broad range of cells, in response to many distinct stimuli. The ability to monitor and quantify Cox-2 expression noninvasively in vivo may facilitate a better understanding of the role of Cox-2, both in normal physiology and in different diseases. We generated a "knock-in" mouse in which the firefly luciferase reporter enzyme is expressed at the start site of translation of the endogenous Cox-2 gene. Correlation of luciferase and Cox-2 expression was confirmed in heterozygous Cox-2luc/+ mouse embryonic fibroblasts isolated from the knock-in mouse. In an acute sepsis model, following injection of interferon gamma and endotoxin, ex vivo imaging and Western blotting demonstrated coordinate Cox-2 and luciferase induction in multiple organs. Using both paw and air pouch inflammation models, we can monitor repeatedly localized luciferase expression in the same living mouse. Cox-2luc/+ knock-in mice should provide a valuable tool to analyze Cox-2 expression in many disease models.
Ishikawa
Tomo-O
TO
Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, 341 Boyer Hall, 611 Charles E. Young Drive East, UCLA, Los Angeles, CA 90095, USA.
Jain
Naveen K
NK
Taketo
Makoto M
MM
Herschman
Harvey R
HR
D000818:Animals; D052160:Benzothiazoles / Q000008:administration & dosage / Q000378:metabolism; D051546:Cyclooxygenase 2 / Q000096:biosynthesis* / Q000235:genetics*; D053595:Embryonic Stem Cells / Q000201:enzymology; D048888:Fireflies / Q000235:genetics; D055879:Gene Knock-In Techniques / Q000379:methods; D017930:Genes, Reporter; D008156:Luciferases / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D011401:Promoter Regions, Genetic; D015054:Zymosan / Q000008:administration & dosage
D052160:Benzothiazoles; C532924:D-luciferin; D015054:Zymosan; D008156:Luciferases; D051546:Cyclooxygenase 2