Abstract
Quantification of vascular permeability is important for cancer research because tumor neovessels have a higher vascular permeability than that of normal tissue. Previous studies have quantified the mean permeability in the field of view (FOV) of a microscopy or regional permeability by setting region of interests (ROIs) manually. Tumor vascular permeability is spatially heterogeneous but existing methods cannot reflect it. In this study, we developed an imaging method to visualize the heterogeneous vascular permeability. To observe vasculature, we implanted a window chamber on the back of a mouse and fluorescent dye was injected via the tail vein. Three dimensional time-lapse images were acquired by confocal microscopy. Then vascular structure was extracted from the image and multiple ROIs were automatically set in the FOV. Permeability at each point was quantified from fluorescent intensity change and the differences of the permeability in the entire vasculature was imaged as a pseudocolor image. In conclusion we developed an imaging method to visualize heterogeneous vascular permeability. Applying our method to tumor vasculature will contribute to cancer research.
