Fabrication of capillary-like structures with Pluronic F127® and Kerria lacca resin (shellac) in biocompatible tissue-engineered constructs.

The fabrication of large cellular tissue-engineered constructs is currently limited by an inability to manufacture internal vasculature that can be anastomosed to the host circulatory system. Creation of synthetic tissues with microvascular networks that adequately mimic the size and density of in vivo capillaries remains one of the foremost challenges within tissue engineering, as cells must reside within 200-300 μm of vasculature for long-term survival. In our previous work, we used a sacrificial microfibre technique whereby Pluronic® F127 fibres were embedded and then sacrificed within a collagen matrix, leaving behind a patent channel, which was subsequently seeded with endothelial and smooth muscle cells, forming a neointima and neomedia. We now have extended our technique and describe two approaches to synthesize a biocompatible tissue-engineered construct with macro-inlet and -outlet vessels, bridged by a dense network of cellularized microvessels, recapitulating the hierarchical organization of an arteriole, venule and capillary bed, respectively. Copyright © 2016 John Wiley & Sons, Ltd.