Molecular Microbiology & Immunology

Saint Louis University Small Animal Imaging Facility

In vivo imaging has become a standard research tool in medical science. Non-invasive in vivo imaging techniques allow researchers to obtain information not available by other methods. Sequential imaging of the same animal can yield valuable insight to the progression of physiological or pathological processes. Further, the number of experimental animals can be reduced as there is no need to sacrifice animals at multiple time point. The Small Animal Imaging Facility, located in the ABSL-3 facility of the vivarium in the Doisy Research Center, now offers sophisticated equipment for the optical imaging of small animals.

Equipment

The IVIS Spectrum is the flagship of Caliper Life Science’s IVIS line of equipment. It is capable of detecting both luminescent and fluorescent light sources ranging from blue to near-infrared wavelengths using 10 excitation and 18 emission filters. It offers both a planar view (the light source is registered on the animal’s surface) and a single-view 3-D reconstruction of both fluorescent and luminescent reporters. The latter can be viewed in anatomical context using a digital rendering of internal organs (at the present, mouse only). Multiple animals (5 mice or 2 rats) can be imaged simultaneously. The intensity of light emission can be quantified in terms of photons/s/cm2/sr, which is an absolute measurement of tissue radiance independent of all camera settings, and can be compared between separate subjects or experiments.

Planar and 3-D image of orthotopic pancreatic cancer expressing luciferase in Syrian hamsters

Imaging of a GFP-expressing poxvirus in a nude mouse

The IVIS Spectrum is connected to the XGI-8 Anesthesia System. The system uses isoflurane as anesthetic agent, and it is mild enough for repeated daily use in rodents.
Anesthesia gas is supplied to the animals in the imaging chamber through a five-place manifold. Alternatively, the XIC-3 isolation chamber is used to image animals infected with Risk Group 3 agents or agents that cause disease in laboratory animals. In both cases, anesthesia gas is scavenged from the chambers and is absorbed onto activated charcoal.

Uses

Researchers who utilize the IVIS Spectrum work in almost all fields of biomedical research. Among others, the imaging platform can be used in:

• Cancer research: Growth, localization, and metastasis of tagged cancer cells can be imaged. Response to treatment is easily followed longitudinally in the same animal throughout the study.
• Infectious diseases: The spread of pathogens expressing fluorescent or luminescent reporters can be monitored.
• Immunology: The activation and migration of various immune cells can be observed.
• Adoptive transfer models: Engraftment of tagged cells can be monitored.

Numerous animal models are commercially available from Caliper and The Jackson Laboratory.

Training

Click here for a Powerpoint presentation by Braden Sanders from Caliper Life Sciences about the IVIS Spectrum.

After initial training, users can operate the imaging apparatus independently. If you are interested in using the equipment, please contact Karoly Toth (toth@slu.edu).

Manuals

IVIS Spectrum
Living Image 3.1 (25 Mb file)
How to use the XGI-8
Connecting the XIC-3 isolation chamber
Luciferin injection
Luciferin preparation
Coelenterazine