November 30, 2009
Israeli Professor Works to Regenerate Lost Limbs
As seen at TheMediaLine.org
An Israeli researcher’s breakthrough provides a major boost to the regeneration of human tissue.
Zilberman’s most notable invention involves soluble fibers that can be used to form a biologically active and flexible ‘scaffolding’ to encourage tissue and bone regeneration in humans.
The flexible scaffolding, shaped so that regenerating bone will take the proper form, can release drugs in a controlled fashion and then completely dissolve into non-toxic material.
“The main idea here is that we succeeded in developing a scaffold that is not only biodegradable but that also releases very sensitive bioactive agents in a controlled manner,” Professor Zilberman told The Media Line. “So for example if a segment of a bone is missing then we could use such a scaffold to promote cell growth and regeneration of damaged tissue.”
Zilberman said the challenge she faced was to develop a fiber that allowed for the release of drugs that break down easily.
“The technology to build a three dimensional, biodegradable scaffold to replace damaged tissue or bone already exists,” she explained. “We did not invent this part, it’s exactly the same polymers that are used, for example, in biodegradable sutures.”
“But the problem is that it’s not very easy to incorporate sensitive molecules such as proteins into a scaffold without destroying their activity,” Professor Zilberman said. “What we did was incorporate bioactive agents, such as any type of drug or protein molecules, that enhance tissue regeneration and growth into the scaffolding. That’s the major accomplishment here.”
Zilberman has not only succeeded in embedding bioactive materials into the scaffolding, but has developed a mechanism to control their release.
“The bioactive protein molecules are released in a controlled manner,” she explained. “So for example in many applications we would like to have a burst release, a relatively high quantity of a drug released during the first week and then decrease the rate over time. Or if we want we could have a constant release over many months, but the point is that we can control the release profile.”
Zilberman’s invention, which has been tested both in vitro and on animal models, could take a variety of physical forms.
“We have developed the fiber,” she said. “We could use these fibers as sutures or we could use them to create a three dimensional scaffold to replace missing bone. We haven’t yet tested it with large bones but there is potential… The scaffold would just dissolve over time and a new tissue will grow in its place.”
In the meantime, Zilberman says her invention is most likely to be used for smaller scale applications.
“When we need to put dental implants, for example, sometimes the bone mass of the patient is insufficient and we first need to enable the growth of further bone mass before inserting the dental implants,” she said. “This would be perfect for that.”
Professor Zilberman has used the same technology to develop wound dressings that allow for the controlled release of antibiotics as well as a drug-carrying fiber platform that can form the basis for biodegradable stents used to keep weak arteries from collapsing.
Zilberman’s research is in the process of being licensed through Ramot, Tel Aviv University’s technology transfer company.