Microthreads Enhanced With Human Cells Help Mice Grow New Muscle

Skeletal Muscle

Longitudinal view of human skeletal muscle.Wikimedia Commons

Future stitches could be made out of your own muscle cells, ensuring proper re-growth of injured muscle tissues.

Researchers in Massachusetts are implanting injured mice with microthreads coated with human muscle cells, reports Technology Review. The threads are made of the same proteins the human body uses to heal wounds, and when seeded with muscle cells, they act as a scaffold for the construction of healthy tissue.

In a study presented earlier this month, George Pins, associate professor of bioengineering at Worcester Polytechnic Institute, and his colleagues sliced out 30 percent of the lower leg muscle in some mice. They took microthreads made of the protein fibrin and coated them with human muscle cells that had been discarded during surgery, Tech Review says. Then they implanted the microthreads into the mouse muscle wounds.

Within a couple days, the cells integrated into the mouse tissue; after a week, the microthreads started to degrade. After 10 weeks, the wound was full of human cells, according to Pins.

Traumatic muscle injuries often don't heal well because scar tissue can prevent them from functioning properly. And for muscle regeneration techniques to work, the tissue must align properly, or the muscles won't contract.

The wounded mice had less scar tissue, suggesting the microthread technique could solve that problem, Tech Review reports. And the microthreads seemed to simulate native wound healing, signaling other cells to migrate to the wound area and grow new tissue in the right alignment. The researchers believe the microthreads even stimulated the mice to regrow their own tissue, not just human cells, but they need confirmation.

The next step is to determine whether the new human tissue behaves like real muscle.