Fabricating Tissues In Situ with the Controlled Cellular Alignments.

Tissue engineering techniques have enabled to replicate the geometrical architecture of native tissues but usually fail to reproduce their exact cellular arrangements during the fabricating process, while it's critical for manufacturing physiologically relevant tissues. To address this problem, we here report a "sewing-like" method of controlling cellular alignment during the fabricating process. By integrating the stretching step into the fabricating process, we are able to create a static mechanical environment which, in turn, would regulate the subsequent cellular alignment, elongation, and differentiation in the generated tissues. With this method, patterned cellular constructs can be fabricated with controlled cellular alignment. Moreover, our method shows a potent capability to fabricate physiologically relevant skeletal muscle constructs in vitro by mechanically inducing myoblast fusion and maturation. As a potential clinical application, aligned myofibers were directly fabricated onto injured muscles in vivo, which repair the damaged tissues effectively. This study shows that our "sewing-like" method can produce engineered tissues with precise control of cellular arrangements and more clinically viable functionalities. This article is protected by copyright. All rights reserved.