Bioprinting Scaffolds for Vascular Tissues and Tissue Vascularization

Abstract

In recent years, tissue engineering has achieved significant advancements towards the repair of damaged tissues. Until this day, the vascularization of engineered tissues remains a challenge to the development of large-scale artificial tissue. Recent breakthroughs in biomaterials and three-dimensional (3D) printing have made it possible to manipulate two or more biomaterials with complementary mechanical and/or biological properties to create hybrid scaffolds that imitate natural tissues. Hydrogels have become essential biomaterials due to their tissue-like physical properties and their ability to include living cells and/or biological molecules. Furthermore, 3D printing, such as dispensing-based bioprinting, has progressed to the point where it can now be utilized to construct hybrid scaffolds with intricate structures. Current bioprinting approaches are still challenged by the need for the necessary biomimetic nano-resolution in combination with bioactive spatiotemporal signals. Moreover, the intricacies of multi-material bioprinting and hydrogel synthesis also pose a challenge to the construction of hybrid scaffolds. This manuscript presents a brief review of scaffold bioprinting to create vascularized tissues, covering the key features of vascular systems, scaffold-based bioprinting methods, and the materials and cell sources used. We will also present examples and discuss current limitations and potential future directions of the technology.

Novel In Situ-Cross-Linked Electrospun Gelatin/Hydroxyapatite Nonwoven Scaffolds Prove Suitable for Periodontal Tissue Engineering

“…As an example, a gelatin methacryloyl hydrogel was produced in a microextrusion approach as a cell-laden scaffold for periodontal tissue engineering [118]. Despite the promising features of 3D bioprinting, however, it has some drawbacks, including the need for specific bioinks and inaccuracies in droplet placement [119]. In comparison with 3D bioprinting, where cells are possibly directly incorporated into the scaffold, the population of electrospun biomaterials by externally seeded cells allows for the selective study of cellular penetration.…”

Vascularization Strategies in 3D Cell Culture Models: From Scaffold-Free Models to 3D Bioprinting

“…Vasculogenesis refers to the de novo formation process observed when precursor cells such as angioblasts differentiate into endothelial cells, sparking the onset of the formation of a primitive vascular network [ 76 ]. Angiogenesis, however, refers to the development of newer vasculature from pre-existing blood vessels [ 77 ]. Angiogenesis is the preferred methodology to introduce vascularization in 3D tissue models; it is preferred over creating tubule-like vascular structures, partly due to the difficulty in the high-precision fabrication of capillary structures (<10 μm) [ 77 ].…”

3D Bioprinting: Introduction and Recent Advancement

“…Bioprinting requires the right cell choice for efficacious print of functional tissue. Parenchymal and nonparenchymal cells whereby cells with structural, supportive, or barrier functions have to be included to generate bioprinted vascular (Hauser et al, 2021). Cells incorporated should maintain cellular homeostasis and the potential for self-renewal while delivering their assigned functions after printing to recapitulate the entire tissue physiology (Hauser et al, 2021).…”

“…Parenchymal and nonparenchymal cells whereby cells with structural, supportive, or barrier functions have to be included to generate bioprinted vascular (Hauser et al, 2021). Cells incorporated should maintain cellular homeostasis and the potential for self-renewal while delivering their assigned functions after printing to recapitulate the entire tissue physiology (Hauser et al, 2021). Besides that, the cells used should exhibit robustness to support the printing process and have control over the cells to avoid excessive proliferation of hyperplasia or apoptosis (Hauser et al, 2021).…”