Duke University scientists have grown functional human muscle tissue in the lab. The team grew the muscle tissue from “myogenic precursors” – cells that have developed beyond stem cells but are not yet muscle cells, and then tested the tissue’s contractile and other responses.

From the Duke University press release:

To see if the muscle could be used as a proxy for medical tests, Bursac and Madden studied its response to a variety of drugs, including statins used to lower cholesterol and clenbuterol, a drug known to be used off-label as a performance enhancer for athletes.

The effects of the drugs matched those seen in human patients. The statins had a dose-dependent response, causing abnormal fat accumulation at high concentrations. Clenbuterol showed a narrow beneficial window for increased contraction. Both of these effects have been documented in humans. Clenbuterol does not harm muscle tissue in rodents at those doses, showing the lab-grown muscle was giving a truly human response.

microscopic image of lab-grown muscle tissue

A microscopic view of lab-grown human muscle bundles stained to show patterns made by basic muscle units and their associated proteins (red), which are a hallmark of human muscle. Photo credit: Duke University; used with permission

Read more about the work and its implications for toxicity testing and disease modeling here. Watch video of the engineered muscle tissue below: