Engineered human organ-specific urethra as a functional substitute

Urologic patients may be affected by pathologies requiring surgical reconstruction to re-establish a normal function. The lack of autologous tissues to reconstruct the urethra led clinicians toward new solutions, such as tissue engineering. Tridimensional tissues were produced and characterized from a clinical perspective. The balance was optimized between increasing the mechanical resistance of urethral-engineered tissue and preserving the urothelium’s barrier function, essential to avoid urine extravasation and subsequent inflammation and fibrosis. The substitutes produced using a mix of vesical (VF) and dermal fibroblasts (DF) in either 90%:10% or 80%:20% showed mechanical resistance values comparable to human native bladder tissue while maintaining functionality. The presence of mature urothelium markers such as uroplakins and tight junctions were documented. All substitutes showed similar histological features except for the noticeable decrease in polysaccharide globules for the substitutes made with a higher proportion of DF. The degree of maturation evaluated with electron microscopy was positively correlated with the increased concentration of VF in the stroma. Substitutes produced with VF and at least 10% of DF showed sufficient mechanical resistance to withstand surgeon manipulation and high functionality, which may improve long-term patients’ quality of life, representing a great future alternative to current treatments.