Research - Animal Imaging Core Laboratory
Zheng-Zheng Shi, M.D.
Jennifer Jacobs, B.Sc.
The Animal Imaging Core Laboratory of the Department of Radiology at TMHRI is a specialized core facility that provides resources, services, and expertise necessary to perform multimodality imaging studies on laboratory animals, including PET, SPECT, CT, MRI/MRS, ultrasound, and optical imaging, as well as the related animal procedures. Using these non-invasive imaging technologies, we are able to acquire “real-time” anatomic, biochemical, physiological/functional, and pharmacological information in a living body (in vivo). The same animals can be scanned repetitively over time; this allows a longitudinal observation of biological activities and disease development, as well as body’s response to a treatment, generating more meaningful data but requiring substanitially fewer animals. Moreover, these imaging-based methods developed with laboratory animals are readily “translational”; they can be translated to clinical studies using the corresponding clinical imaging modalities.
- To provide resources and services of animal imaging studies including PET, SPECT, CT, MRI/MRS, ultrasound, and bioluminescence/fluorescence imaging. The core will perform not only the scans (data acquisition), but also post-imaging data processing and analysis, and result interpretation.
- To provide services of animal procedures related to the above imaging studies. These include general animal care and handling, animal preparation and monitoring prior to and during imaging, and certain specific procedures such as xenograft tumor models and tissue collection.
- To support the Imaging Chemistry Group (see the related webpage) in its effort to develop novel imaging agents, nanoparticles, therapeutic compounds and agents by providing pharmacokinetics evaluation by means of in vivo PET/CT, SPECT/CT, and optical imaging.
- To carry out collaborative research with emphasis on cellular imaging and trafficking.
The Animal Imaging Core Laboratory was established in 2007 using funds provided by Houston Methodist Research Institute. During the past year, we have completed the essential instrumentation for multimodality imaging studies on small laboratory animals (mice and rats), including in vivo bioluminescence and fluorescence imaging, integrated small animal PET, SPECT and CT imaging (see below), and we have also built up a team that is well trained to operate these systems as well as to provide animal care and handling. More importantly, our core has obtained close communication and strong support from experts of synthetic chemistry and radiochemistry, imaging processing, and bioinformatics who are faculty members of the same department (Radiology) at TMHRI (see the related webpage). In the near future, we will extend our capacity of animal imaging from small animals to large animals such as rabbits and dogs, and we are also seeking to acquire a high-field MRI system for animal dedicated MR studies.
The following imaging services are currently available at the Animal Imaging Core Laboratory:
- Integrated small animal PET, SPECT and CT imaging systems
We have installed the Inveon Dedicated PET System and the Inveon Multimodality (SPECT/CT) system (Siemens Medical Solutions). These two systems can be operated as standalone high-performance microPET and high-resolution SPECT/CT scanners, and can also be “docked” together to form a “3 in 1” scanner, enabling the real integration of PET/CT, SPECT/CT, and PET/CT/SPECT imaging. The PET and/or SPECT signals can be easily “fused” onto CT images. In addition, Inveon also offers the industry’s highest PET resolution (≤ 1.4 mm) and sensitivity, advanced multi-pinhole SPECT collimators for improved sensitivity and spatial resolution, and high resolution CT analysis (down to 15 micron) and real-time image reconstruction.
- In vivo bioluminescence/fluorescence imaging: the Xenogen IVIS200 system
The scanner has an integrated fluorescence system (400–900 nm) that allows easy switching between fluorescent and bioluminescent spectral imaging applications, and a laser scanner that provides 3D surface topography for single-view diffuse tomographic reconstructions of internal sources. It is also equipped with excitation and emission filters for GFP, DsRed, Cy5.5, and ICG in addition to a set of four background filters for subtraction of auto-fluorescence. It permits high-throughput imaging of up to 5 mice (or 3 rats) simultaneously via gas anesthesia.
- Small animal high-intensity focused ultrasound (HIFU)
See Medical Physics Laboratory (Brian O’Neil).