A new era of virtual histology: novel contrast agents for 3D multi-tissue imaging using contrast-enhanced computed tomography

Biological tissues have a spatial heterogeneity. Thus, 2D measurements like histomorphometry only partially reveal their full 3D morphology. We propose contrast-enhanced computed tomography (CE-CT) for 3D structural quantification of biological tissues and 3D immunological imaging. Previously, we explored commercially available and in-house synthesized contrast agents (polyoxometalates - POMs). In this project, as pioneers in the field, we aim to set the stage for a new era of virtual 3D histology using CE-CT by developing and validating novel CE-CT contrast agents. A multidisciplinary approach will be used, crossing the boundaries between biology, engineering, imaging and chemical synthesis, making this project unique. First, different POM formulations will be evaluated for their binding efficiency, image contrast and cost. As case study, the bone marrow vascularization in human osteoarthritic and osteonecrotic femoral heads will be evaluated. Then, a novel iodine-based contrast agent will be synthesized to specifically stain saturated lipids. A high fat diet-induced Type 2 diabetes mouse model will be applied to validate this contrast agent. Next, the existing compound CA4+ will be further optimized in terms of net charge. Finally, a novel CE-CT antigen-specific staining method will be developed for immunological imaging. The two latter staining methods will be tested in a murine fracture healing model and for assessing the ‘maturity’ of engineered cartilage intermediates.