Researchers implant tissue engineered bladdersBMJ 1999; 318 doi: https://doi.org/10.1136/bmj.318.7180.350b (Published 06 February 1999) Cite this as: BMJ 1999;318:350
Bladders grown in the laboratory with tissue engineering techniques have been successfully implanted and shown to function in animals, according to a study published in Nature Biotechnology (1999;17:140-55).
Dr Anthony Atala, a surgeon and director of the tissue engineering laboratory, and a team from the Boston Children's Hospital and Harvard Medical School claim that this advance is the first laboratory grown mammalian organ. The team hopes to begin human trials with the technique within the next two years.
In the study, bladders were removed from 14 dogs. Two dogs had no reconstructive procedure; six received an implant of a cell free, bladder shaped biodegradable polymer; and six received bladder “neo-organs” grown in the laboratory. Dr Atala explained how the “neo-organs” were produced: “We took small biopsies of tissue, teased apart the layers, and grew the urothelial tissue and muscle tissue separately in culture. Then we applied the tissue to a mould of biodegradable material, with epithelium on the inside and muscle tissue on the outside.” The new organs were ready for implantation within five weeks.
Urodynamic studies showed that the dogs receiving the tissue engineered implants regained 95%of their original bladder capacity, were continent, and voided normally. At necropsy, which occurred up to 11 months later, the implanted organs were completely covered with epithelium and muscle tissue, and showed both angiogenesis and nerve growth. Dogs who did not undergo reconstructive procedures or who had polymer implants did not regain normal bladder capacity.
The ability to implant new bladders would potentially be useful in babies with congenital bladder conditions and in people who have lost their bladders to trauma or cancer.