A new method of repairing damaged bones
The human body is often unable to cope with the recovery of severe traumatic bone tissue injuries on its own. In such cases, doctors resort to the introduction of specialized growth factors. However, such therapy requires the introduction of a large number of expensive drugs that can spread beyond the damage zone and stimulate the formation of undesirable elements of bone tissue around it.
Researchers have developed a complex of the most commonly used bone growth factor BMP-2 and microparticles of the drug heparin, the concentration of BMP-2 in which is 1000 times higher than the maximum indicator that was previously achieved.Researchers at the Georgia Institute of Technology, working under the guidance of Associate Professor Todd McDevitt, have developed a technology that provides more efficient delivery of bone growth factors with high accuracy and low financial costs.
The technology consists in the creation of microparticles from modified heparin methacrylamide, forming intermolecular bonds with growth factors when heated. Heparin is a widely used anticoagulant whose chemical properties make it ideal for binding growth factors. The authors demonstrated that the microparticles they developed have an exceptionally high affinity for the most commonly used growth factor in clinical practice, bone morphogenetic protein-2 (BMP-2), 1000 times higher than the maximum binding capacity of other heparin-containing biomaterials.
Currently, collagen sponges are used to deliver BMP-2 to the injury zone, releasing a large amount of the drug immediately after their introduction into the body. To compensate for this effect, an excessive amount of the drug is injected into the sponges, which leads to its nonspecific and ineffective delivery. Unlike sponges, heparin microparticles firmly bind BMP-2 molecules, which ensures their slow gradual release. Experiments have shown that only 25% of the drug is released within 28 days.
The authors also demonstrated that BMP-2 retains its activity after the release of their microparticles and stimulates an increase in the number of target cells in culture. In the near future, they plan to conduct experiments on animal models.
Article by Marian H. Hettiaratchi et al. Heparin microparticle effects on presentation and bioactivity of bone morphogenetic protein-2 is published in the journal Biomaterials.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on the materials of Georgia Institute of Technology:
Engineering a Better Way to Rebuild Bone Inside the Body.
02.06.2014