Growing back a lost limb
Israel21c (Link) (November 30, 2009)
An Israeli researcher has developed a biologically active �scaffolding� of soluble fibers which could be used to regenerate lost or damaged bone and tissue.
If a lizard loses its tail, it grows right back, but for human beings a lost limb can never be replaced. Now, however, thanks to breakthrough research from Israel, we may one day be able to regenerate lost or damaged human limbs as effectively as a lizard replaces its tail.
Prof. Meital Zilberman of Tel Aviv University has developed a new biologically active �scaffold� made from soluble fibers, which could be used to help humans replace lost or missing bone or tissue.
The artificial and flexible scaffolding releases growth-stimulating drugs to the place where new bone or tissue is needed. It connects tissues together in much the same way as scaffolding is used to surround an existing building when additions to that building are made.
With more research, says Zilberman, it could also serve as the basic technology for regenerating other types of human tissue, including muscle, arteries, and skin.
�The bioactive agents that spur bone and tissue to regenerate are available to us. The problem is that no technology has been able to effectively deliver them to the tissue surrounding that missing bone,� explains Zilberman of the university�s Department of Biomedical Engineering.
Going out on a limb
Zilberman�s invention, which hasn�t yet been named, could be used to restore missing bone in a limb lost in an accident, or to repair receded jawbones to secure dental implants. The scaffold can be shaped so that the bone will grow into the proper form. After a period of time, the fibers can be programmed to dissolve, without a trace.
Though it�s still early days, Zilberman�s technology also has potential uses in cosmetic surgery. Instead of using silicon implants to square the chin or raise cheekbones, the technology could be used to �grow your own� cheekbones or puffy lips.
�Our material is very special,� says Zilberman: �The fibers not only support body parts like bones and arteries. They�re also specially developed to release drugs and proteins in a controlled manner. Our special 3-D matrix can hold together drugs that are particularly vulnerable to breaking down easily. The matrix gives the body shape and form, coaxing it to re-grow and strengthen missing parts.�
Zilberman started her work in biomaterials at the UT Southwestern Medical Center at Dallas in Texas, and is now focusing on various medical applications. Her research is being licensed through Ramot, the technology transfer company of Tel Aviv University.
The basic building blocks of bones and tissues
Scientific peer-reviewed research on Zilberman�s scaffold fiber has appeared in a number of journals, including Acta Biomaterialia. In vitro results on bone have been good, and some basic unpublished results from animal models have also shown excellent promise for bone regeneration, the professor adds.
�It sounds simple, but it�s not. It�s quite difficult to develop a process for scaffold formation for bone growth. It�s a delicate balance to apply only mild conditions that will not destroy the activity of the growth factor molecules,� she explains.
So far, Zilberman has developed both a fibrous artificial scaffold and an organic scaffold which forms a film. The technology could also be applied to peripheral nerve regeneration.
�Our fibers provide all the advantages that clinicians in tissue regeneration are calling for,� asserts Zilberman. �Being thin, they�re ideal when delicate scaffolds are called for. But they can also be the basic building blocks of bones and tissues when bigger structures are needed.�