Human muscle that contracts has been grown in the lab.

Existing models of human skeletal muscle are two-dimensional and do not mimic the structure or behaviour of natural tissue well. Nenad Bursac at Duke University in Durham, North Carolina, and his colleagues took samples of living human muscle cells and grew them in three dimensions using a scaffold. This coaxed the cells into forming muscle that could spontaneously twitch. When the team stimulated it with electrical pulses similar to nerve signals, the muscle contracted.

The tissue also responded to various drugs, including a steroid-like one, in much the same way as human muscles. The researchers plan to use their tissue to test drugs for muscle disorders.

eLife http://doi.org/zfs (2015)