Sustained Perfusion for Improved Long-Term Viability in Large Bioprinted Constructs

摘要

Vascularization is a key challenge in developing physiological tissues. Here, bioprinting technology is applied to create a large-scale construct with perfusable lumens, a first step towards clinically relevant vascularized tissues. This material was developed using principles from microextrusion printing and casting techniques. A perfusion connector was designed and fabricated to allow for flow through a multitude of parallel structures without requiring individual intubation. Fabricated structures were able to maintain fluid flow under ambient conditions for 5 weeks. Further refinement to allow for improved uniformity of perfusion is underway. This study has shown proof of concept in the development of a large, hydrogel-based construct with sustained perfusion. Moving forward, progress will focus on the inclusion of cells during the printing process, modifications to the gel precursors, and testing of the device under relevant environmental conditions. The inclusion of a multitude of simultaneously perfusable channels shown will, we hypothesize, improve long term cellular viability in constructs with dimensions surpassing the oxygen/nutrient diffusion limit and be a primary stepping stone for the development of clinically relevant bioengineered tissues.