MULTI-MATERIAL BIO-PRINTIG FOR NASAL OSTEOCHONDRAL TISSUE ENGINEERING

Abstract

One of the main difficulties faced by nasal Tissue Engineering (TE) methods is the recapitulation of complex 3D tissue environments that mimic native anatomy, including the nasal osseocartilaginous interface region. Bio-printing is an emerging TE method that can fabricate constructs with precise placement of multiple bio-inks to create 3D multi-material TE constructs. However, such methods rely on sequentially adding bio-inks, resulting in discontinuity between the different regions. This can cause stress concentrations and improper signalling across the discontinuity. Resolving this issue would greatly improve the bio-functionality of constructs with physiologically relevant interface. An extrusion bio-printing method that can be used to fabricate 3D scaffolds with a continuous junction across different bio-inks is introduced, by combining two bio-ink outlets into a single channel and seamlessly switching between ‘on-the-fly’, resulting in a continuous bio-printed construct with physiologically relevant gradient interfaces. This bio-printing method was used in conjunction with silk-based bio-inks to fabricate the nasal osseocartilaginous junction to show that a seamless gradient junction can be formed with 3D fidelity. The resulting construct was seeded with different cells to better understand the effect of cellular gradients on the resulting bio-printed construct.