To develop a tissue-engineered bladder wall replacement with elements obtained from non-urinary tract components is an atractive idea. The aim of this study was to compare growth of hair follicles epithelial stem cells and mesenchymal stem cells to urothelial cells and fibroblasts cells on scaffold prepared from rat collagen type I.
Materials and methods: Wistar rats were used in experiment. Rat urothelial cells, hair follicles epithelial stem cells, mesenchymal stem cells and 3T3 cells were cultivated in DMEM (Sigma) supplemented with 10% (or 20% for hair follicles cells) of Fetal Bovine Serum (FBS). Epithelial cell cultures were suplemented with EGF (10 ng/ml; Sigma). Cells were stained using anti-cytokeratine (Clone MMF) and anti-cytokeratine 7. Anti-CD34 and anti-p63 staining were done. Collagen scaffold was prepared from tendoms of Wistar rat's tails. 6-well plates were covered with collagen scaffold. 25 x 10(3) of cells were seeded on each well and cultured for a week. Cells in the controls were seeded on polystyrene surface. After a week cell viability was assessed using MTT test (Sigma). Each experiment was triplicated. Photo documentation was prepared. The differences between means were compared using t-Student test.
Results: There were 106.5 +/- 23.4 x 10(3) and 310.7 +/- 60.7 x 10(3) of 3T3 fibroblasts growing on polystyrene and collagen, respectively (p < 0.05). The initial cell number was 25.0 x 10(3). Urothelial cells expressed epithelial markers. There were 40.0 +/- 4.2 x 10(3) and 4.5 +/- 1.8 x 10(3) urothelial cells growing on polystyrene and collagen, respectively after 7 days of culture (p < 0.01). There were 118.5 +/- 19.7 x 10(3) and 114.1 +/- 33.2 x 0(3) of mesenchymal stem cells growing on polystyrene and collagen, respectively (NS). Hair follicles epithelial cells expressed epithelial markers and were slightly positive for CD34 and p63. There were 292.5 +/- 33.3 x 10(3) and 167.4 +/- 24.9 x 10(3) of hair follicles epithelial cells growing on polystyrene and collagen, respectively (p < 0.05). Collagen scaffold decreased proliferation of follicle epithelial and urothelial cells.
Conclusions: Hair follicles epithelial stem cells and mesenchymal stem cells can be potentially used in tissue-engineering, with the guarantee of the sufficient cell number for transplantation. It seems that construction in vitro of urinary bladder walls from elements obtained from non-urinary tract tissues is feasible.