Feasibility study of a novel urinary bladder bioreactor.

We have devised a bioreactor to simulate normal urinary bladder dynamics. The design permits a cell-seeded scaffold made from a modified porcine acellular matrix to be placed between 2 closed chambers filled with culture medium and be mechanically stimulated in a physiologically relevant manner. Specifically designed software increased hydrostatic pressure from 0 to 10 cm of water in a linear fashion in 1 chamber, resulting in mechanical stretch and strain on the scaffold.

Quantifying angiogenesis in VEGF-enhanced tissue-engineered bladder constructs by dynamic contrast-enhanced MRI using contrast agents of different molecular weights.

Purpose: To compare Gadomer, a macromolecular magnetic resonance (MR) contrast agent, and gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA) for quantifying angiogenesis in tissue-engineered bladder constructs.

Materials And Methods: Constructs enhanced with vascular endothelial growth factor (VEGF) were grafted onto the bladder of 12 rabbits (N= 3/VEGF, VEGF = 0,10,15,20 ng/g tissue). After eight days dynamic contrast-enhanced MRI (DCE-MRI) was performed in each animal using Gadomer and Gd-DTPA, separated by a one-hour interval.

Porcine bladder acellular matrix porosity: impact of hyaluronic acid and lyophilization.

Bladder acellular matrix (ACM) is being investigated as a urinary bladder replacement scaffold. We have demonstrated that ACM is porous and theorized that this contributes to ACM fibrosis and contracture over time in vivo and may preclude uptake and retention of molecules, which may aid cellular repopulation. We sought to determine if hyaluronic acid (HA) would decrease ACM porosity.