Posted on by Dr. Francis Collins
When you do a hard workout at the gym, or run a marathon, you generate lots of little tears in muscle. This is usually not a problem and may even lead to improved muscle strength—because the injury activates stem cells in the muscle (called satellite cells) that replicate and form new muscle fibers to repair and rebuild the damaged tissue. But when injuries extend beyond the normal wear and tear—a major injury or resection, for example—this amazing self-healing system isn’t enough. That’s when a self-healing, lab-grown muscle transplant would be particularly useful—but we haven’t yet been able to create this in a dish.