TABLE 2.
Pre-clinical studies utilizing electrospun scaffolds for tissue engineering of urethra and ureter.
|
Urethra | |||||||||
| Study | Biomaterial | Electrospinning Method | Fiber Diameter (nm) | Solvent | Cell Source | Animal Model | Scaffold Shape (and Size) | Follow-up time | Outcome |
| Lv et al. (2016) | PLLA/PEG | Single-jet | 500–1500 | Chloroform/DMF | hAMSCs | Rabbit | Onlay (2*1.5 cm) | 12 weeks | No stricture and fistula Formation of a multilayered urothelium, and alignment of smooth muscle cells along the scaffold fibers in the pre-seeded group |
| Wang D.J. et al., 2015 | PLA | Single-jet | NA | Dichloromethane | ADSCs | Rabbit | Onlay (1*0.5 cm) | 6 weeks | The incidence of urethrostenosis in the pre-seeded group was 50% lower than bare scaffold Formation of multilayered urothelium with organized, smooth muscle cells with lower inflammation in the pre-seeded group |
| Zhang et al. (2015) | PLCL/Collagen loaded with ICG-001 (Wnt pathway inhibitor) | Coaxial | 457 ± 82 | 2,2,2-Trifluoroethanol/DMSO | B-UCs | Rabbit | Tubularized (2*1 cm) | 12 weeks | Wide caliber urethra without strictures and fistulas Less ECM deposition, and more developed smooth muscle and epithelium layers |
| Xie et al. (2013) | Silk fibroin | Single-jet | 800–1200 | Water | B-UCs | Dog | Onlay (3.2*1.2 cm) | 24 weeks | Wide caliber urethra without signs of stricture and fistula Well-developed stratified urothelial cells in the tissue-engineered group |
| Fu et al. (2009) | PLLA | Single-jet | 3000–5000 | Chloroform | Rabbit urethra urothelial cells | Rabbit | Tubular (variable based on the size of stricture induced by PTUS) | 24 weeks | Complete coverage of urothelial cells No stricture, voiding difficulty, and other complications |
|
Ureter | |||||||||
| Kloskowski et al. (2014) | PLCL | Single-jet | 810–2150 | Chloroform/DMF | None | Rat | Tubular (1 cm) | 4 weeks | Regeneration of urothelium Focal regeneration of smooth muscle layer Hydronephrosis and ureter extension Patency of anastomosis site in 4 out of 6 animals |
PLLA/PEG, poly(L-lactic acid)/poly(ethylene glycol); DMF, N,N-dimethylformamide; hAMSCs, human amniotic mesenchymal cells; PLA, Poly(Lactic Acid); ADSCs, adipose tissue-derived stem cells; DMSO, dimethyl sulfoxide, B-UCs, bladder urothelial cells; PLLA, poly(L-lactic acid); PTUS, post-traumatic urethral stricture; PLCL, poly(L-lactide-co-caprolactone).