Hydrogel for muscle regeneration

Very often, elderly patients who have suffered injuries suffer from non-healing damage to muscle tissue. Therapy with muscle stem cells from donors could be useful in such cases, but to date, doctors do not have effective methods of introducing such cells into the injury zone.

Researchers at the Georgia Institute of Technology, working under the guidance of Associate Professor Young Jang, propose a solution to this problem with the help of a molecular matrix – hydrogel developed by them, which allows the introduction of muscle stem cells, also known as satellite cells of skeletal muscles, directly into the damaged tissue of patients.

The usual introduction of satellite cells into damaged inflamed tissue is ineffective in part because on their way the stem cells meet with the cells of the patient's immune system that kill them. Only from 1% to 20% of the injected muscle stem cells fall into the damage zone, while even the surviving cells are weakened. Moreover, some tissue damage makes it impossible to carry out any injections.

The hydrogel offered as an alternative protects stem cells, which not only remain viable, but also actively divide inside the hydrogel matrix. When it is applied to the damaged muscle, the cells take root and promote tissue regeneration.

Usually a hydrogel is a three-dimensional molecular "network", as if suspended in water and giving it the consistency of a gel. The peculiarity of the material developed by the authors is that in addition to cross-linked threads, the hydrogel framework has special "latches" – molecules interacting with proteins of the cell surface. The presence of such molecules not only enhances cell adhesion, but also prevents their suicide, since in the free state stem cells are prone to triggering the process of apoptosis, or programmed cell death.

In experiments on old mice, applying a hydrogel containing muscle stem cells to damaged muscles stimulated the healing process and prevented the development of serious immune reactions.

In addition, the method demonstrated good results on a mouse model of Duchenne muscular dystrophy. This serious disease affects one out of 3,500 boys and subsequently leads to their death due to atrophy of the respiratory muscles. The authors hope that in the future the approach they have developed will save the lives of such patients by restoring their diaphragmatic muscles. They also note that if the method reaches the stage of clinical trials, they will have to find a way to minimize the risk of developing a rejection reaction of donor cells.

Article by Woojin M. Han et al. Synthetic matrix enhancements transplanted satellite cell engraftment in dystrophic and aged skeletal muscle with comorbid trauma is published in the journal Science Advances.

Evgenia Ryabtseva, portal "Eternal Youth" http://vechnayamolodost.ru Based on materials from Georgia Institute of Technology: This Matrix Delivers Healing Stem Cells to Injured Elderly Muscles.