Biomedical engineers at Johns Hopkins have developed a new liquid material that in early experiments in rats and humans shows promise in restoring damaged soft tissue relatively safely and durably. The material, a composite of biological and synthetic molecules, is injected under the skin, then "set" using light to form a more solid structure, like using cold to set gelatin in a mold. The researchers say the product one day could be used to reconstruct soldier's faces marred by blast injuries.
The Hopkins researchers caution that the material, described in a report in the July 27 issue of Science Translational Medicine, is "promising," but not yet ready for widespread clinical use.
"Implanted biological materials can mimic the texture of soft tissue, but are usually broken down by the body too fast, while synthetic materials tend to be more permanent but can be rejected by the immune system and typically don't meld well with surrounding natural tissue," says Jennifer Elisseeff, Ph.D., Jules Stein Professor of Ophthalmology and director of the Translational Tissue Engineering Center at the Johns Hopkins University School of Medicine. "Our composite material has the best of both worlds, with the biological component enhancing compatibility with the body and the synthetic component contributing to durability."
The researchers created their composite material from hyaluronic acid (HA), a natural component in skin of young people that confers elasticity, and polyethylene glycol (PEG), a synthetic molecule used successfully as surgical glue in operations and known not to cause severe immune reactions. The PEG can be "cross-linked"or made to form sturdy chemical bonds between many individual moleculesusing energy from light, which traps the HA molecules with it. Such cross-linking makes the implant hold its shape and not ooze away from the injection site, Elisseeff says.
To develop the best PEG-HA composite with the highest
|Contact: Vanessa McMains|
Johns Hopkins Medical Institutions