Practical Methods for Molecular In Vivo Optical Imaging

Abstract

Traditional approaches for translating observations of molecular events into the context of a living organism have suffered from the requirements for either sacrificing animals at multiple time points prior to labor-intensive analyses of multiple tissues, or have relied on subjective observations or measurements of the animals over time. Recently an explosion of dedicated animal imaging modalities and the release of modified clinical imaging devices dedicated for animal imaging have allowed for the design of quantitative real time experiments incorporating fewer animals and providing whole animal analyses. Of these modalities, optical imaging (bioluminescence and fluorescence) has emerged as a powerful research tool, allowing investigators with limited whole animal imaging expertise to rapidly and inexpensively translate models produced in cellular assays into the context of a living animal. Here we will outline the steps necessary for translation of models established in culture systems into rodents.

Keywords: Bioluminescence; fluorescence; molecular imaging; non-invasive; reporter; whole animal.

Fig 1

Different stage heights provide different fields of view, such that multiple animals may be imaged at one time (high throughput) or a single region of one animal may be imaged (high resolution).

Fig 2

(A) Representative image produced for mice with luciferase labeled ovarian cancer cell line implanted into the peritoneal cavity. Individual tumor nodules can be visualized. (B) The tumor burden from these mice was quantified as a measure of light output and plotted over time (with each graph representing an individual mouse implanted with the same tumor cell line).