2/11/2025 Jenny Applequist
Written by Jenny Applequist
The technology opens the possibility of wireless treatment of cardiac and other conditions.
For years, Cunjiang Yu’s group has pursued the dream of developing bioprinted tissue that could be embedded in a patient and stimulated remotely by light, without any connective wiring or genetic modification, to achieve therapeutic or diagnostic goals. In January, his team published in Science Advances a description of a major milestone in that effort: a bioprinted cardiac tissue they developed that can be remotely stimulated by light, and their experimental demonstration of the tissue’s use to manipulate a rat’s heart rate.
Yu, who is a Founder Professor of electrical and computer engineering, explains that medical stimulation of patients’ internal tissues has been done for some time—for example, stimulation of muscle tissue to treat pain, or of brain tissue to treat neurological conditions—but that it’s required invasive hardware. “You have to have a wire... [or] have a pin penetrate into the body,” he says.
In recent years, the possibility of “optogenetics”—whereby tissues are genetically modified to be remotely manipulable via light—has introduced a new option, albeit one that has potential side effects and other limitations.
But Yu has nursed a greater ambition: to find a way to manipulate tissue remotely, using either light or some other type of electromagnetic waves, such that neither invasive probes nor genetic modification are needed.
The new paper details his team’s design and experimental validation of a bioprinted cardiac tissue that can fulfill that dream.
Bioprinting is a technology for manufacturing tissue from hydrogel inks, and Yu explains that the combination of bioprinting with functional components, thereby forming a specialized ink suspension, has opened the door to creation of tissues that support medical interventions. The approach has made it possible not only to create replicas of natural tissues—even entire organs—but to create “functionalized tissues” with valuable attributes not found in natural tissue.
Specifically, in the newly published work, the team mixed micro-solar cells into ink that was then used to print “scaffold” structures, which could be bonded onto a target living tissue surface. In their experiment, the target surface was the heart of a live rat under sedation. The researchers showed that they could successfully manipulate the rat’s heart rate by stimulating the scaffold via exposure to light.
The paper notes that potential medical applications of the cardiac scaffold include replacement of damaged tissue followed by modulation that could restore normal beating to an injured heart. It could also be used, for example, to support recovery from a stroke, or to treat or prevent ventricular tachycardia. Light-activated bioprinted tissues could also be used for parts of the body other than the heart.
Yu says that the publication is the culmination of a long effort. “Personally, I feel like this is something we really put our heart in for a good number of years,” he says. “Andwe thought this could be a game-changing technology.”
He credits his own “hardworking students and postdoc” as well as his collaborators, particularly Dr. Yu Shrike Zhang of the Harvard Medical School, for the success of the project.
Yu is also looking forward to where his team, and the broader research community, go from here.
“This is probably one of the first works in this field, and we continue to work on it,” he says. “I think that this could really create a lot of new opportunities, a new field, for this community.”
Among other ongoing work, his team is now studying multiple promising avenues for overcoming the challenges of exposing tissue, once it’s been deeply embedded in a patient, to sufficient light.
Illinois Grainger Engineering Affiliations
In addition to his primary ECE appointment, Yu has affiliations with the departments of Materials Science and Engineering, Mechanical Science and Engineering, and Bioengineering, and with the Beckman Institute for Advanced Science and Technology, the Materials Research Laboratory, and the Holonyak Micro and Nanotechnology Laboratory.