Surgical Bioengineering of the Microvasculature and Challenges in Clinical Translation

Abstract

Tissue and organ dysfunction are major causes of worldwide morbidity and mortality with all medical specialties being impacted. Tissue engineering is an interdisciplinary field relying on the combination of scaffolds, cells, and biologically active molecules to restore form and function. However, clinical translation is still largely hampered by limitations in vascularization. Consequently, a thorough understanding of the microvasculature is warranted. This review provides an overview of (1) angiogenesis, including sprouting angiogenesis, intussusceptive angiogenesis, vascular remodeling, vascular co-option, and inosculation; (2) strategies for vascularized engineered tissue fabrication such as scaffold modulation, prevascularization, growth factor utilization, and cell-based approaches; (3) guided microvascular development via scaffold modulation with electromechanical cues, 3D bioprinting, and electrospinning; (4) surgical approaches to bridge the micro- and macrovasculatures in order to hasten perfusion; and (5) building specific vasculature in the context of tissue repair and organ transplantation, including skin, adipose, bone, liver, kidney, and lung. Our goal is to provide the reader with a translational overview that spans developmental biology, tissue engineering, and clinical surgery.

Impact Statement

This translational article provides a concise review of microvascular engineering efforts to date within the context of grafts, flaps, and entire organ replacement. Our article systematically and logically discusses current developments, challenges, and novel approaches in microvascular engineering. It provides a readable starting point for understanding various approaches and the implications of successful vascularization at the microvascular level as well as how surgical approaches can be used to facilitate connections to the recipient macrovasculature.