Scientists make 3D heart using personalized bio-ink

Credit: Rebecca Enright/Art Editor Credit: Rebecca Enright/Art Editor

Over the last several years, 3D printing technology has allowed designers and enthusiasts to produce all sorts of items without an extensive manufacturing pipeline, from shoes to artwork to robots. There have been some applications in medicine, such as “printing” drugs and prosthetics, but never something as complex and critical as a human organ.

That changed this month when researchers at Tel Aviv University in Israel created the first 3D-printed vascularized engineered heart using a patient’s own cells and biological materials. The artificial heart completely matches the immunological, cellular, biochemical, and anatomical properties of the patient.

“This is the first time anyone anywhere has successfully engineered and printed an entire heart replete with cells, blood vessels, ventricles, and chambers,” said lead scientist and professor at the Tel Aviv University School of Molecular Cell Biology and Biotechnology Tal Dvir in a press release. The research was conducted in Dvir’s lab along with professor Assaf Shapira of the Tel Aviv University Life Sciences Department and doctoral student Nadav Moor.

Scientists in the field of regenerative medicine have only been able to print simple tissues without cells or blood vessels thus far. They have recreated the 3D structure of a heart but nothing more. Dvir’s breakthrough is an artificial organ using personalized tissue that serves as bio-ink, substances made of sugars and proteins that can be used for printing complex tissue models. According to Dvir, the results demonstrate the potential for organ replacement in the future. “At this stage, our 3D heart is small, the size of a rabbit's heart,” he explained. “But larger human hearts require the same technology.”

In order to construct the engineered heart, a biopsy of fatty tissue was extracted from patients. The cellular materials of the tissue were then separated, and were reprogrammed to become pluripotent stem cells. Remaining materials, particularly the extracellular matrix (a network of extracellular macromolecules such as collagen and glycoproteins), were processed into a hydrogel that served as the bio-ink for printing. The bio-ink was mixed with the reprogrammed cells, which then differentiated into cardiac or endothelial cells. Together, these components created cardiac patches with blood vessels that were compatible with the specific patient’s immune system.

“The biocompatibility of engineered materials is crucial to eliminating the risk of implant rejection, which jeopardizes the success of such treatments,” Dvir clarified. “Ideally, the biomaterial should possess the same biochemical, mechanical, and topographical properties of the patient's own tissues. Here, we can report a simple approach to 3D-printed thick, vascularized, and perfusable cardiac tissues that completely match the immunological, cellular, biochemical, and anatomical properties of the patient.”

The researchers plan to expand upon their work by culturing the engineered hearts in order to “teach” them the tasks performed by natural hearts. Currently, the cells can contract but are unable to work together. Dvir hopes that with further development his team’s artificial heart can actually pump blood. He said, “Maybe, in ten years, there will be organ printers in the finest hospitals around the world, and these procedures will be conducted routinely.”