Engineering the vascular tree

The field of tissue engineering encompasses a wide array of disciplines, from life sciences to engineering and clinical sciences, with the shared goal of creating human tissue mimics for transplantation or observation. At its core, tissue engineering aims to develop mathematical and experimental models for understanding mammalian tissue and to devise scaffolds and methodologies for repairing, maintaining, and constructing tissues and organs in clinical settings. Despite remarkable progress, tissue engineering still faces significant challenges, particularly in creating large, cell-dense tissues and organs such as cardiac muscle, liver, and kidney. Current approaches often rely on porous biomaterials to support cell function, limiting the size of constructs due to diffusion limitations for oxygen and nutrients. To overcome these challenges, researchers are exploring methods to mimic the hierarchical vascular networks found in vivo, which play a crucial role in tissue function. In embryogenesis, blood vessel formation occurs through vasculogenesis and angiogenesis, processes regulated by signaling pathways like Vascular Endothelial Growth Factor (VEGF).
One approach to creating thick tissues involves mimicking the composition and construction of these vascular networks. Mechanical forces, such as blood flow patterns, play a key role in shaping vessel morphology and structure. However, replicating these structures in vitro remains a significant challenge. Arterioles, with their ability to regulate blood flow and deliver nutrients, are critical components of the vascular tree. Engineering arterioles remains a gap in tissue engineering, essential for creating thick tissues.