Muscle Fibers (IMAGE) Brigham and Women's Hospital Caption Researchers have been able to grow differentiated muscle fibers (green) in the lab. Nuclei shown in blue. Credit Olivier Pourquie, Brigham and Women's Hospital Usage Restrictions Credit required License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.