The bladder as a bioreactor: Urothelium production and secretion of growth hormone into urine
Uroplakin genes are expressed in a bladder-specific and differentiation-dependent fashion. Using a 3.6-kb promoter of mouse uroplakin II gene, we have generated transgenic mice that express human growth hormone (hGH) in their bladder epithelium, resulting in its secretion into the urine at 100-500 ng/ml. The levels of urine hGH concentration remain constant for longer than 8 months. hGH is present as aggregates mostly in the uroplakin-delivering cytoplasmic vesicles that are targeted to fuse with the apical surface. Using the bladder as a bioreactor offers unique advantages, including the utility of all animals throughout their lives. Using urine, which contains little protein and lipid, as a starting material facilitates recombinant protein purification.
Publication Source (Journal or Book title)
Kerr, D., Liang, F., Bondioli, K., Zhao, H., Kreibich, G., Wall, R., & Sun, T. (1998). The bladder as a bioreactor: Urothelium production and secretion of growth hormone into urine. Nature Biotechnology, 16 (1), 75-79. https://doi.org/10.1038/nbt0198-75