Figure 3. Scheme for bioprinting an organ construct with a ‘built in’ intra-organ branched vascular tree.
A. Solid vascular tissue spheroids (red = endothelial cells; green = smooth muscle/pericytic cells). B. Uni-lumenal vascular tissue spheroids with a single lumen (red = endothelial cells; green = smooth muscle/pericytic cells). C. Tissue-specific spheroids with internal microvascular networks (yellow = tissue-specific cells; red = microvasculature). D. Bioprinting of a large-diameter vascular segment using solid vascular tissue spheroids. E. Bioprinting of an intermediate-diameter vascular segment using uni-lumenal vascular tissue spheroids with a single lumen. F. Bioprinting of an organ segment using tissue-specific spheroids with internal microvascular networks G. Bioprinting of a vascularized organ segment using all three types of tissue spheroids.