Scientists bioprint tissue-like constructs capable of controlled, complex shape change
Published in Bioprinting.
Where standard 3D printing uses a digital blueprint to manufacture an object out of materials like plastic or resin, 3D bioprinting manufactures biological parts and tissues out of living cells, or bioinks. A fourth dimension — shape transformation over time — can be achieved by incorporating materials that enable printed constructs to morph multiple times in a preprogrammed or on-demand manner in response to external signals.
Bioprinting 4D constructs provides opportunities for scientists to better mimic the shape changes that occur during the development, healing and normal function of real tissues and fabricate complex structures.
A new study in the science journal Advanced Materials describes the development of a new cell-laden bioink, comprised of tightly-packed, flake-shaped microgels and living cells, for bioprinting 4D constructs. This new system enables the production of cell-rich bioconstructs that can change shape under physiological conditions.
Titled “Jammed Micro-Flake Hydrogel for Four-Dimensional Living Cell Bioprinting,” the study is authored by engineers at the University of Illinois Chicago who created the bioink and conducted experiments of prototype hydrogels.
Their experiments resulted in a variety of complex bioconstructs with well-defined configurations and high cell viability, including a 4D?cartilage-like tissue formation. Further designs demonstrate complex, multiple 3D-to-3D shape transformations in bioconstructs fabricated in a single printing.
“This bioink system provides the opportunity to print bioconstructs capable of achieving more sophisticated architectural changes over time than was previously possible. These cell-rich structures with pre-programmable and controllable shape morphing promise to better mimic the body’s natural developmental processes and could help scientists conduct more accurate studies of tissue morphogenesis and achieve greater advances in tissue engineering,” said study corresponding author Eben Alsberg, Richard and Loan Hill Chair, who has appointments in the departments of biomedical engineering, mechanical and industrial engineering, pharmacology and regenerative medicine, and orthopaedics.
Alsberg says the bioink advances previous technologies in several ways.