The long-term objective of this proposal is to investigate the cellular and molecular mechanisms of growth factors mediated regeneration of acellular bladder matrix using both in vitro and in vivo models and its potential clinical use. The hypothesis is that growth factors (TGFb1, EGF, KGF and VEGF) will stimulate the process of regeneration of acellular matrix bladder when grafted to the host bladder (normal, diabetic and interstitial cystitis) after partial cystectomy. These growth factors will stimulate the process of ingrowth of smooth muscle, urothelial lining, vascularization and innervation in the regeneration of new functional bladder.
Specific Aim # 1. Effects of growth factors (TGFb1, EGF, KGF and VEGF) on regeneration of bladder morphology and growth using normal and diseased bladder. Under this specific aim, the investigators will test the hypothesis that growth factors will stimulate the process of regeneration of acellular matrix bladder when grafted to the host bladder (normal and diseased such as diabetic and interstitial cystitis) after partial cystectomy. To test this hypothesis following experiments will be conducted: (a). Effects of growth factors on epithelial migration and growth in normal and diseased bladder. (b). Effects of growth factors on smooth muscle cells migration and growth in normal and diseased bladder. (c). Effects of growth factors on invasion of blood vessels and nerves in normal and diseased bladder.
Specific Aim # 2. Functional studies of matrix-directed regenerated bladders in normal and diseased hosts treated with growth factors. Under this specific aim, they will test the hypothesis that the augmented bladder after acellular matrix grafting in normal and diseased hosts (diabetic and interstitial cystitis) will be re-innervated with cholinergic and adrenergic nerve fibers and perform normal voiding function through their receptors. To test this hypothesis, following experiments will be done: (a). In vivo bladder functional studies by micturition pattern. (b). In vitro bladder functional studies by tissue bath experiments. (c). Immunochemical studies of adrenergic and cholinergic nerves of regenerated bladder.
Specific Aim # 3. Cellular and molecular mechanisms of growth factor-induced and matrix directed bladder regeneration in normal and diseased hosts. Under this specific aim, they will test the hypothesis that gene and protein expression of growth factors (TGFb1, EGF, KGF and VEGF) will enhance reepithelization, vascularization and innervation of matrix-directed bladder regeneration in normal and diseased hosts (diabetic and interstitial cystitis). To test this hypothesis, following experiments will be done: (a). To analyze gene expression of growth factor TGFb1, EGF, KGF and VEGF in host and regenerated bladder.; (b). To analyze protein expression and localization of growth factors TGFb1, EGF, KGF and VEGF in host and re-generated bladder. (c). To analyze gene and protein expression of receptors for growth factors TGFb1, EGF, KGF and VEGF in host and re-generated bladder.
Specific Aim # 4. Clinical application of matrix-directed bladder regeneration. The investigators will initiate clinical trials for bladder augmentation and urethral stricture repair using organ specific acellular matrix.
