In vivo Noninvasive Small Animal Molecular Imaging

Abstract

The remarkable efforts that are made on molecular imaging technologies demonstrate its potential importance and range of applications. The generation of disease-specific animal models, and the developments of target-specific probes and genetically encoded reporters are another important component. Continued improvements in the instrumentation, the identification of novel targets and genes, and the availability of improved imaging probes should be made. Multimodal imaging probes should provide easier transitions between laboratory studies, including small animal studies and clinical applications. Here, we reviewed basic strategies of noninvasive in vivo imaging methods in small animals to introducing the concept of molecular imaging.

Keywords: animal imaging; computed tomography; magnetic resonance imaging; nuclear imaging; optical imaging; ultrasonography.

Figure 1.. Multimodal imaging modalities for small animal imaging.

Figure 2.. Multimodal imaging modalities for preclinical and clinical research.

Figure 3.. Schematic illustration of direct imaging with a target-specific probe. Stars are radioisotope labeled, fluorescent, or magnetic probes.

Figure 4.. Strategy of the promoter-reporter gene construct for monitoring gene expression using optical imaging. P is a promoter/ enhancer sequence.

Figure 5.. Schematic illustration of three-type reporter gene expression used in nuclear imaging modalities. Stars are radioisotope labeled substrates (enzyme) or ligands (receptor) or the radioisotope itself (transporter type).

Figure 6.. Strategies of promoter-reporter gene constructs for monitoring gene expression. P1, P2 are promoter/enhancer sequences. Gene1, Gene2, Gene3 and Gene4 can be reporter genes; internal ribosomal entry site (IRES); ribosomal skipping 2A sequence from foot-and-mouth disease virus (F2A), porcine teschovirus-1 (P2A), and Thosea asigna virus (T2A).