Scientists Figure Out How to Make Muscles from Scratch
Scientists Figure Out How to Make Muscles from Scratch.
For the past several years, Nenad Bursac has been trying to make muscles from scratch.
A biological engineer at Duke, Bursac came close in 2015, when his lab became the first to grow functional human skeletal muscle in culture. "Functional" being the operative word. Like the muscle fibers in, say, your bicep, the tissues could contract and generate forces in response to things like electrical pulses and shots of chemicals.
But to produce the tissue, the researchers had to isolate their starting materials from pea-sized globs of muscle, which they sliced from human test subjects. The lab was, in effect, growing muscle from muscle. It was a significant accomplishment, but also kind of a letdown: Biopsied cells don't proliferate well in the lab, so producing a large, consistent supply is difficult. What's more, Bursac is interested in developing models of muscular disorders (muscular dystrophies, for example). But for the 2015 study, his lab sampled healthy tissues; sampling it from someone with a muscle-wasting disease, he says, would be unethical.
"In a lot of people with rare, congenital diseases, their muscles are already damaged, so you don't want to biopsy on top of that and cause further damage," Bursac says. "The ideal scenario is to take a skin, blood, or urine sample, use that to generate stem cells, and use that to generate functional muscles." In other words: Reprogram skin or blood cells to act like undifferentiated stem cells.