Scientists have recently been able to create a 3D-printed heart and arteries, as well as structural copies of the brain and other organs, using collagen, fibrin and a seaweed substance called alginate.
The research was published on October 23 in the journal Science Advances, and was conducted by a team of experts at Carnegie Mellon University in Pittsburgh, Pennsylvania.
The scientists created two miniature organs (a human brain and a baby chicken heart), as well as an artery tree, with magnetic resonance imaging and microscopy images serving as models.
They used a Makerbot 3D printer, whose nozzle had been modified with a syringe, in order to build soft tissues out of organic materials.
Normally, such printers use plastic, and when replacing that with collagen or other more fragile substances there is a heightened risk that the newly created shapes will fail to stay intact, and instead collapse under their own weight.
Therefore, researchers sought to reinforce the material, and after thinking of the way Jell-O molds can be used in order to keep fruit suspended they decided to incorporate gelatin particles into the structure.
They added the mayonnaise-like gel in order to support the shapes that were being built by the Makerbot 3-D printer.
Upon completing the organ replicas, they could easily remove the collagen slurry by heating the printed objects at body temperature, give the fact that the melting point of the gel was much lower than that of the structures.
The approach, called FRESH (freeform reversible embedding of suspended hydrogels), allowed the soft body parts to remain in place and successfully hold their shape, without suffering any sort of distortion.
“We’ve been able to make MRI images of coronary arteries and 3D images of embryonic hearts and 3D bioprint them with unprecedented resolution and quality”, explained Adam Feinberg, associate professor at Carnegie Mellon University.
According to Anthony Atala, tissue engineer and director at the Wake Forest Institute for Regenerative Medicine in Winston-Salem, North Carolina, the recently developed technique surpasses all prior ones, when it comes to the complexity and lifelike appearance of the replicas.
Similarly, Jonathan Butcher, biomedical engineer at Cornell University who creates 3D-printed heart valves, has called the new achievement “stunning”
Before, 3-D printing had only been used in the health sector for creating more rigid materials, such as prosthetics.
For example, in September it was announced that a Spanish man with a cancerous tumor in his chest wall had received a 3D-printed titanium implant which could replicate the structure of his ribcage and sternum.
Back in 2014, another patient who suffered from cancer of the calcaneus benefited from a heel bone implant, also printed in titanium.
Scientists have even used 3D printing in order to implant dissolvable airway splints, which were used for treating 3 infants suffering from severe tracheobronchomalacia, a life-threatening disease which can cause cardiac arrest.
The promising results of this study suggest that custom-made, artificial tissues and organs required for life-saving transplants may be more easily achievable and less cost-prohibitive than previously thought.
For now, scientists are carrying out follow-up research in order to devise a way for incorporating live cells into the model organs.
The plan is to develop functional heart muscle, in order to test new drugs and analyze heart disease evolution more carefully, with the ultimate aim of repairing heart defects or heart attack damage.
Image Source: Science Advances