Wound healing: the main thing is the correct orientation

In the USA, they learned how to grow muscles with the help of micronitesDmitry Tselikov, Compulenta
Employees of Worcester Polytechnic Institute (USA) managed to eliminate a large wound in the muscle tissue of mice by growing and implanting micronites covered with a layer of human muscle cells.

Microniti seems to have helped the cells grow in the right direction. The latter is necessary to restore the working capacity of muscle tissue. "We assume that the cells migrate along these scaffolding," explains the creator of the micronite George Pince. The implanted cells are quickly embedded in existing muscles and reduce the formation of scar tissue.

Modern medicine is not capable of special feats if a patient with large lacerations is in front of her. As it heals, thick layers of scar tissue form in the muscles, which do not allow the muscles to fully restore their working capacity. Several approaches to solving the problem are being developed – this includes growing muscles in a "test tube" and injecting stem cells. But they all rest on the same thing: to heal large wounds, it is important to make the cells grow into a properly oriented structure.

Microniti consists of fibrin, a protein polymer that the body uses to initiate the wound healing process. To create the filaments, the researchers had to learn how to simultaneously extrude fibrinogen (the building block of fibrin) and thrombin (an enzyme that catalyzes the synthesis of soluble fibrinogen proteins into a polymer) from two small tubes. The diameter of the thread is from 500 to 100 microns, that is 5-10 times larger than the size of the cell.

Then the threads were seeded with human muscle cells obtained from postoperative waste. Before that, bioengineer Ray Page and his colleagues grew cells in conditions that made them "younger" (that is, become immature, less specialized) in order to enhance their ability to regenerate tissues.

During the experiments, the researchers removed about 30% of the tibial anterior muscle in mice, which is located in the front of the lower leg, and implanted microniti with cells.

According to scientists, fibrin filaments replace a natural signaling system that controls the healing process of wounds. They also attract an enzyme that destroys fibrin by releasing fibrinogen proteins: they are the ones that encourage surrounding cells to migrate and grow new tissues.

Apparently, the cells are implanted into the host tissues in just a couple of days. After a week, the microniti begin to decompose, and they are replaced by muscle fibers. After ten weeks, the wound is finally filled with human cells that look like mature muscle fibers.

Now scientists are finding out to what extent the new tissue acts like normal muscles. Preliminary data suggest that the implants also caused the growth of native muscle cells. In addition, microniti seems to have significantly reduced the production of collagen, the main component of scar tissue.

Perhaps, for the first time, scientists managed to completely heal a muscle wound.

The results of the study were presented at a symposium on bioengineering, which was held at Worcester Polytechnic Institute.

Prepared based on the materials of Technology Review: Microthreads Help Grow New Muscles.

Portal "Eternal youth" http://vechnayamolodost.ru16.11.2010