Smart Dressing Harnesses the Body’s Own Proteins to Accelerate Wound Healing

Deep skin wounds can be difficult to treat, and the available methods are often too short-acting or lack proper targeting to the wound site. But a newly developed biomaterial may overcome these challenges.

Researchers at Imperial College London developed a new wound dressing that assembles and delivers the body’s own healing proteins at the precise time and place where they’re needed. They showed that the material could accelerate healing in wounds on mouse skin as well as on living human skin tested in a lab.¹ They published their results in Nature Materials.

Stubborn wounds put a huge burden on healthcare systems. For example, diabetic foot ulcers, caused by poor circulation and lack of sensation, affect nearly 19 million people each year, with one in five cases leading to an amputation.²

To heal wounds quickly, an orchestra of different cellular and biochemical factors needs to play together at the right time and place. The conductors of this process are proteins called growth factors, which direct cells to migrate, replicate, and then restore damaged tissue. But to heal stubborn wounds, these signals need to be heard in the right place and for long enough for wounds to respond. Existing treatments address this issue by blasting large doses of growth factor drugs into wound areas, but these proteins still often struggle to last long enough in the wound to make a difference.

Previous teams of researchers have tried to improve on these more rudimentary approaches by using targeted delivery strategies. These respond to signals in the wound environment, like enzymes, light, or even magnetic fields. The Imperial College London team developed a platform that responds to a signal from within the body: The cellular traction forces that move cells together when wounds close.

The platform consists of nucleic acids called aptamers that latch onto nearby healing growth factors, holding them in place until cellular forces cause them to loosen their grip, releasing the factors into the wound. The platform can be tailored so that only forces produced by certain cell types activate it.

Ben Almquist, a bioengineer at Imperial College London and coauthor of the study, said in a statement, “What particularly stands out with this research is that the patient's own body becomes the pharmacy. We are not delivering a manufactured drug and hoping it survives long enough to work. We are capturing what the body is already making and giving it back to the cells that need it.”

The researchers tested their aptamer platform in a series of models, beginning with rats and mice. In each model, the team loaded up the aptamers with different growth factors and then released them into the wounds. In rats with leg wounds, collagen sponges seeded with the platform enhanced a healing process called vascularization compared with control sponges without the platform. In mice with skin wounds, the same sponges reduced the wound size after 10 days compared to control sponges. When the researchers tested the material on human skin, the dressing sped up tissue growth.

“What excites me most is that this works in living human skin. We can see repair cells migrating into the wound dressing and confirm the material is engaging with human biology. That result makes me optimistic that this approach has a future in the clinic,” said Magdalene Ho, a bioengineer at Imperial College London and coauthor of the study, in the statement.