Ultra-High Resolution Angiogenesis Imaging using μCT

Aims As a classical hallmark of cancer, angiogenesis is essential for enabling tumors to grow beyond a size of 1-2 mm. Therefore, the visualization and quantification of functional tumor blood vessels within tumors is essential for assessing treatment responses to anti-angiogenic therapies. In experiments using tumor xenografts, anti-angiogenic effects are generally evaluated by immunohistochemistry (IHC). This method, however, has several limitations. For example, the functionality and the 3D architecture of tumor blood vessels are not fully considered. To overcome these shortcomings, we established a protocol based on ex vivo high-resolution micro-computed tomography (μCT) for the 3D visualization and characterization of the microvascular network in tumors. Similar studies were performed in mouse models of liver and kidney fibrosis. To date, such systematic and highly detailed 3D analyses of vascular branching resulting in an angiogenic characterization based on ultrahigh resolution μCT and 3D volume rendering have not yet been described.