Building vascular structures in 3D
Tags: 3D Bioprinting
As the field of 3D bioprinting matures, increasingly challenging applications of biofabrication are being undertaken. One such challenge is the construction of vascular networks, which can support the growth of larger tissue constructs by transporting vital nutrients and growth factors to the construct, while removing metabolic waste. This area of tissue engineering was recently reviewed by authors from the University of Saskatchewan in the Journal of Pharmaceutical Analysis, with a particular focus on recent examples of 3D printing directed to recreating vascular networks for tissue regeneration.
In addition to the complex three-dimensional architecture which must be recreated when printing a vascular structure, a truly representative construct must also allow incorporation of the relevant progenitor cells (such as endothelial progenitor cells). In this sense, a successful effort to fabricate a functional vascular construct will require high print fidelity and optimal methods, while providing sufficient biocompatibility to allow proliferation of embedded cells within the structure.
In terms of printing methodology, extrusion printing and inkjet deposition were highlighted as common methods used for the construction of vascular structures. Often these approaches require the use of sacrificial or fugitive materials which can be used in a print, encapsulate, dissolve workflow to form a hollow channel akin to a vascular structure. Commonly applied materials for this purpose include carbohydrate glass filaments and Pluronic F127. In addition, through emerging co-axial printing methodologies it is possible to print hollow fibres in real time.
The biopolymers used in the examples highlighted in this review vary from naturally-derived (alginate, collagen, fibrinogen, silk fibroin, laminin, Matrigel), synthetically-modified (GelMA, modified ceramics, alginate-PVA) to fully synthetic (PEG, Pluronic F127, PEUU). Each example describes the specific hardware, methodology, and materials to address a specific application, and it is clear that judicious choice of each variable is necessary for success in this fledgling area.
You might like: