动物实验 z-bo 2020-08-31 450

　　Researchers at the University of Pittsburgh School of Medicine used porcine extracellular matrix (ECM) to induce stem cells into muscle cells. The study found that muscles lost due to traumatic accidents or muscle injuries can be regenerated by transplanting these cells.

　　According to a new study of five patients, muscle loss caused by traumatic accidents and military injuries may increase significantly. After injury, skeletal muscle may regenerate, but it cannot regenerate under extreme conditions. Under extreme conditions, a large amount of skeletal muscle will be destroyed (this situation is called volumetric muscle loss or VML). The treatment of VML is so limited that it is difficult for patients to perform daily activities. Stem cells have been shown to help regenerate damaged tissues. Most stem cell therapies follow the same pattern: Researchers collect stem cells, separate them, grow them into target cells, and then reinject them into the patient. Steven Badilak and Brian Shikari and colleagues developed another stem cell technology that does not involve the addition of stem cells, but uses porcine extracellular matrix (ECM) to induce stem cells into muscle cells. In the first proof

　　After the ECM method is effective for rodents with severe hindlimb injuries, the researchers applied it to patients with a limb muscle loss of 58% to 90%.. They tested this technique on 5 male patients, at least 6 away from the injured site Months, and the surgery and physical therapy of these patients were unsuccessful. Three of the patients were from the military, two were injured in the leg due to an improvised explosive device (IED) explosion, and the other was injured in the leg muscle due to exercise. The other two patients were civilians who were injured in the leg muscles caused by the skiing accident.

　　Before the operation, due to dysfunction, all patients completed a 12-16 week physical therapy plan. When these therapies stagnated, there was no sign of any further improvement, and all patients currently undergo ECM stent placement. Researchers used surgical methods to remove scar tissue from these patients and added ECM materials. Then, each patient immediately resumed the preoperative physical therapy program and received physical therapy for 5 to 23 weeks. The indicator of successful treatment is that the ability of these patients is at least improved compared to the patient's maximum ability of daily activities before surgery. 25% (raise one foot when walking, stand up from a chair, raise one leg to a sitting position, etc.). For each patient, their muscles are regenerated, and this regeneration can partially restore normal muscle appearance. When MRI and computed tomography image analysis were performed on the treated muscles, the researchers found that dense tissue formed at the implant site 6 months after the operation. After implantation, the matrix scaffold material degrades and acts as an induction and recovery device to attract stem cells to the injured site. These stem cells then grow into muscle cells, thereby promoting the development of new healthy muscle tissue. The quality of life of all patients improved, but the researchers determined that 3 out of 5 patients improved their function by 25%. The author of the article pointed out that post-treatment physical therapy is very important to the effectiveness of treatment. Physical therapy can trigger the generation of signals that direct stem cells to become muscle cells, rather than other cell types. For newly wounded soldiers, such as newly wounded patients, the treatment is more effective. Badilak said: "The ability to treat patients immediately will be an advantage of this technology."