“Once engineered tissues are made in the lab, the only way for them to get into the human body is by a surgical approach, by opening the chest to place the tissues in,” biomedical engineering professor Milica Radisic told Digital Trends. “In this work, we were able to marry minimally invasive delivery with tissues engineering [to develop] shape memory polymer scaffolds that enable us to inject fully functional tissues into the body.”
The term “shape memory” refers to a material with the ability to return to its original default shape at a certain temperature. In this case, it means that the smart patch could be injected through a needle, and then unfold itself into a bandage-like shape once inside a patient. The results would be organ repair with no surgery more invasive than the injection of a small needle. It is one of a number of exciting new projects that will allow for less invasive surgery to be carried out, thereby reducing risks for patients.
The scaffold itself is made out a biocompatible, biodegradable polymer. Over time, this material breaks down to leave only the new tissue behind. “We are particularly excited about using this technology to inject patches of heart tissue for the treatment of myocardial infarction, although we can deliver other tissues as well,” Radisic said. These tissues might include organs like the liver.
So far, the technology has been tested effectively on hearts in pigs and rats, where the subjects not only survived the operation but did so with flying colors. In the experiment with post-heart damaged rats, the injected patch allowed them to pump more blood than they did without it. While it does not restore heart function entirely, it could still greatly improve the quality of life for patients.
Radisic said that the team hopes to carry out human trials in the future, although this will almost certainly be “years” away. “This will likely be done through a startup company,” Radisic concluded.
A paper describing the work was recently published in the journal Nature Materials.
