Abstract:Objective: To construct a tissue-engineered bladder patch with multilayer structure and abundant vascularization on the basis of bladder acellular matrix (BAM) combined with various cells wrapped up in omentum. Methods: Bone marrow mesenchymal stem cells (BMSCs), bladder epithelial cells and bladder smooth muscle cells of rabbits were seeded on the surface of BAM at 1.0×106cells/mL, respectively. After 10 days of cultivation, bladder epithelial cells-smooth muscle cells-BMSCs-BAM tissue engineered bladder patch was prepared. In the experimental group, tissue engineered bladder patch were wrapped on silica gel catheter and implanted into rabbit omentum for culture. In the control group, BAM patch was wrapped on silica gel catheter and implanted into rabbit omentum for culture. Samples in two groups were taken for immunohistochemistry after 4 weeks and 8 weeks respectively. The epithelial layer was detected by CKAE1/AE3 antibody, the smooth muscle layer was detected by α-SMA antibody and the angiogenesis was detected by CD31 antibody. Results: After 4 weeks, epithelial layer and smooth muscle layer were formed in the experimental group, and obvious neovascularization were found in the bladder patch and CKAE1/AE3, α-SMA and CD31 were expressed positively. After 8 weeks, the epithelial layer and smooth muscle layer in the experimental group became thicker, and the blood vessels became denser and thicker. However, the BAM patch in the control group had only minute angiogenesis, without epithelial layer and smooth muscle layer. Conclusion: Tissue engineered bladder patch with multilayer structure and abundant vascularization can be constructed by BAM combined with bladder epithelial cells, smooth muscle cells and BMSCs and wrapped up in omentum.
