T-shaped posts on one layer of a tissue scaffold pass through the holes in a second layer — similar to the hooks and loops used to fasten Velcro. (Image: Raymond Cheah).
Tissue bioengineering for cardiac repair is a field of intense study. The protocols for heart muscle tissue culture are well established, but the cells that make up laboratory-engineered cardiac tissue often differ from those in the human body. This is primarily due to the lack of support cells, such as fibroblasts and endothelial cells, required for normal growth and function. Researchers from the University of Toronto’s Faculty of Applied Science and Engineering have created a novel tissue scaffold that enables the modular assembly of cardiac tissue sheets. A two-dimensional asymmetrical honeycomb-shaped polymer mesh was devised to facilitate adherence and linear organization of cardiac cells. The flexibility of the biodegradable polymer enables coordinated beating of the adhered cells in response to an electric current.
Honeycomb mesh of cells being compressed by contracting heart cells growing along the scaffold (Image: Boyang Zhang).
The uniqueness of the scaffold lies in the T-shaped posts on the top of the honeycomb, which click into place when a second module is positioned over the top, much like the “hook and loop” mechanism of Velcro. When combined together, the modular sheets begin beating in unison, almost immediately, in response to electrical current. Moreover, because three different sheets were used, each with a different cell type (cardiomyocytes, fibroblasts, and endothelial cells), the result is a tougher engineered tissue that more closely resembles human heart tissue. The relative simplicity of assembly, as well as the robustness and functionality of the sheets, make this a promising technique for further in vivo testing and translation for cardiac repair, as well as repair of various other tissues.
Study in Science Advances: Platform technology for scalable assembly of instantaneously functional mosaic tissues…
Source: University of Toronto…