Researchers engineered the first injectable microtissue containing motor and sensory neurons encased in protective tissue, called tissue engineered neuromuscular interfaces (TE-NMIs). The TE-NMI neurons provide a source of axons to muscles in rats who suffered nerve injuries, and “babysit” the muscles to prevent degeneration and loss of function, while the damaged nerve regrows, according to researchers at the Perelman School of Medicine at the University of Pennsylvania. Their findings were published in Bioactive Materials.