In vivo image analysis using iRFP transgenic mice.

Area of Science:

• Biotechnology
• Molecular Imaging
• Genetics

Background:

• In vivo imaging techniques are advancing with fluorescent proteins emitting light within the optical window.
• Near-infrared (NIR) fluorescent protein (iRFP) offers stable, non-toxic fluorescence without exogenous substrates.

Purpose of the Study:

• To report the generation of transgenic mice with ubiquitous NIR fluorescence expression (iRFP mice).
• To evaluate the utility of iRFP mice as a model for in vivo imaging.

Main Methods:

• Generation of iRFP transgenic mice through genetic engineering.
• Mating of iRFP transgenic mice with wild-type (WT) mice to assess inheritance.
• Analysis of physiological parameters (serum, blood cell indices, body weight) and fluorescence detection in various tissues.

Main Results:

• Successful generation of iRFP transgenic mice with approximately 50% transmission of the iRFP gene.
• iRFP mice showed normal physiological parameters comparable to WT mice.
• Ubiquitous NIR fluorescence (excitation 690 nm, emission 713 nm) was detected in multiple organs of both newborn and adult iRFP mice.

Conclusions:

• Transgenic iRFP mice provide a valuable, self-sufficient model for in vivo near-infrared fluorescence imaging.
• The widespread expression and stability of iRFP in these mice support their application in diverse biological studies and imaging modalities.