Vascularization strategies in tissue engineering approaches for soft tissue repair

Abstract

Insufficient vascularization during tissue repair is often associated with poor clinical outcomes. This is a concern especially when patients have critical-sized injuries, where the size of the defect restricts vascularity, or even in small defects that have to be treated under special conditions, such as after radiation therapy (relevant to tumor resection) that hinders vascularity. In fact, poor vascularization is one of the major obstacles for clinical application of tissue engineering methods in soft tissue repair. As a key issue, lack of graft integration, caused by inadequate vascularization after implantation, can lead to graft failure. Moreover, poor vascularization compromises the viability of cells seeded in deep portions of scaffolds/graft materials, due to hypoxia and insufficient nutrient supply. In this article we aim to review vascularization strategies employed in tissue engineering techniques to repair soft tissues. For this purpose, we start by providing a brief overview of the main events during the physiological wound healing process in soft tissues. Then, we discuss how tissue repair can be achieved through tissue engineering, and considerations with regards to the choice of scaffold materials, culture conditions, and vascularization techniques. Next, we highlight the importance of vascularization, along with strategies and methods of prevascularization of soft tissue equivalents, particularly cellbased prevascularization. Lastly, we present a summary of commonly used in vitro methods during the vascularization of tissue-engineered soft tissue constructs.

Characterization of an Innovative Biomaterial Derived From Human Wharton’s Jelly as a New Promising Coating for Tissue Engineering Applications

“…Therefore, having a uniform and continuous cell layer on the luminal surface of the graft seems to be a prerequisite for obtaining a hemocompatible small-diameter TEVG ( Pashneh-Tala et al, 2016 ). Adding a luminal coating step prior to cellularization in the TEVG manufacture protocol is strongly recommended because it can create a microenvironment that can modify cell behavior by enhancing cell adhesion, proliferation and/or differentiation ( Masson-Meyers and Tayebi, 2021 ). We are one of the multiple teams concerned by the lack of small-caliber vascular substitutes and seeking to develop a long-term patent and efficient small-diameter TEVG.…”

Pro‐angiogenic potential of a functionalized hydrogel scaffold as a secretome delivery platform: An innovative strategy for cell homing‐based dental pulp tissue engineering

“…The angiogenesis assays performed in this study showed the capacity of the CS‐S system to significantly increase and accelerate the capacity of vascular‐like structure formation in all analyzed parameters at 6 h, probably due to the controlled release of important growth, resulting in sustained angiogenesis. This form of analysis of the angiogenesis process is widely validated in the literature, with Matrigel® being the most used base, due to having the ability to evaluate potential pro‐angiogenic factors (Masson‐Meyers & Tayebi, 2021; Stryker et al., 2019). Recruited cells need nutrition to differentiate and form new tissue, and the root canal structure is surrounded by hard tissue with only a foramen that allows the entry of nutrition.…”

The Therapeutic Potential of Exosomes in Soft Tissue Repair and Regeneration

“…Soft tissue injuries, including skin, muscle, tendon, and nerve injury, affect millions of people every year [ 1 , 2 , 3 , 4 , 5 , 6 ]. Studies on tissue repair and regeneration have focused primarily on skin wound healing; however, for complete repair of composite soft tissue defects, healing of tendons, skeletal muscles, and peripheral nerves will also be required to restore function.…”