3d Imaging and visualization of gene therapies in whole animals


Hemi Dimant, Ph.D., Director of Applications for Advanced Pathology Services, Invicro

With major advancements in genetics and bioengineering, gene therapies offer extraordinary promise in restoring normal physiological processes by repairing deleterious molecular alterations. To move gene therapies into clinical trials, it is critical to first characterize the biological behavior of different candidates in preclinical animal studies. While various imaging modalities can support pharmacological research applications ranging from biodistribution, pharmacokinetics, pharmacodynamics and cellular localization, no
single imaging one can support all.
Cryofluorescence tomography (CFT) is a 3D blockface imaging modality in which large samples, such as whole animals or whole organs are embedded in optimal cutting temperature compound followed by sequential sectioning and image acquisition throughout the entire sample. With a high-resolution camera and no signal attenuation, CFT provides higher resolution and sensitivity compared to other fluorescent or chemiluminescent in vivo imaging modalities to answer research questions for gene therapy applications.
In this technical note, you will learn:
  • General considerations that must be taken when designing a preclinical research study examining gene therapies.
  • How CFT bridges the gap between in vivo imaging and histopathology when evaluating test articles in preclinical animals.
  • How a multimodality study was used to understand AAV distribution compared to AAV-mediated protein expression.
  • Importance of running a multimodality study to evaluate ASO pharmacology in the intrathecal space, using SPECT/CT for PK analysis, CFT for biodistribution analysis and immunofluorescence to confirm cellular localization.