Scientists say that they have been able to use bladder cells grown in a laboratory to repair injured urinary systems in boys – an achievement that may mark an advancement in the field of tissue engineering, HealthDay News reported. Common practice is to use pieces of skin to repair boys' injured urethras, but this procedure typically fails. In a new trial, surgeons instead reconnected severed urethras with tube-like structures created from bladder cells. They did this by taking a small bit of tissue, about half the size of a postage stamp, from the bladder and grew the bladder cells into urethra-like tubes. Then, they reconnected the severed urethras with the tubes. Six years later, the five boys – aged 10 to 14 – who underwent the procedure are doing fine, which shows that the tubes are able to grow with the body, according to researchers. "Tissues can be engineered using the patients' own cells, and they last long term," said Dr. Anthony Atala, director of the Wake Forest Institute for Regenerative Medicine and a co-author of the study, of the results. However, despite the apparent success, there are still roadblocks to overcome before this procedure has a chance of becoming a medical standard. More testing needs to be done, and it is still uncertain whether it would work in adults. Also, creating body parts from cells, which is crucial for tissue engineering, is still a challenge. Nevertheless, Atala hopes his findings could pave the way for the creation of other tube-like structures in the body, such as replacement arteries. Scientists are currently in the early stages of testing products for the repair of cartilage, the cornea and the heart. The study was published The Lancet and was funded by the U.S. National Institutes of Health. Click here to read more from HealthDay News.