Tissue engineered extracellular matrices (ECMs) in urology: Evolution and future directions

Abstract

Autologous gastrointestinal tissue has remained the gold-standard reconstructive biomaterial in urology for >100 years. Mucus-secreting epithelium is associated with lifelong metabolic and neuromechanical complications when implanted into the urinary tract. Therefore, the availability of biocompatible tissue-engineered biomaterials such as extracellular matrix (ECM) scaffolds may provide an attractive alternative for urologists. ECMs are decellularised, biodegradable membranes that have shown promise for repairing defective urinary tract segments in vitro and in vivo by inducing a host-derived tissue remodelling response after implantation. In urology, porcine small intestinal submucosa (SIS) and porcine urinary bladder matrix (UBM) are commonly selected as ECMs for tissue regeneration. Both ECMs support ingrowth of native tissue and differentiation of multi-layered urothelial and smooth muscle cells layers while providing mechanical support in vivo. In their native acellular state, ECM scaffolds can repair small urinary tract defects. Larger urinary tract segments can be repaired when ECMs are manipulated by seeding them with various cell types prior to in vivo implantation. In the present review, we evaluate and summarise the clinical potential of tissue engineered ECMs in reconstructive urology with emphasis on their long-term outcomes in urological clinical trials.

From Acellular Matrices to Smart Polymers: Degradable Scaffolds that are Transforming the Shape of Urethral Tissue Engineering

“…Acellular matrices, such as small intestinal submucosa (SIS) and bladder acellular matrix (BAM), are by far the most frequent scaffold type assessed in vivo for urethral tissue repair [57]. SIS is obtained from porcine small intestines, where the mucosal, serosal, and muscular layers are mechanically removed from the inner and outer surfaces of the intestinal wall to leave a 0.1 mm collagen-rich membrane, mostly formed of the submucosa [58,59].…”

Recent Trends in the Management of Bladder Exstrophy: The Gordian Knot Has Not Yet Been Cut

“…Tissue engineering aims to develop alternatives for current techniques in which intestinal tissue is used for patients with inadequate development of bladder capacity. Recent studies using tissue engineered extracellular matrices or acellular scaffolds with growth factor in animal models are promising (50, 51). However, there are scores of open issues which need to be fully clarified and defined before tissue-engineering in urology progresses from bench to bedside in BE-reconstruction.…”

Tissue engineering and stem cell therapy in pediatric urology

“…Acellular extracellular matrices are useful for repairing small urethral defects and cell-seeded extracellular matrices can augment or replace defective tissue segments in the ureter and bladder. [80] Although further immense detailed research is the need of the hour to fully utilize the hidden potential of stem cell research and tissue engineering, there is cautious optimism that the field of tissue engineering will play an increasing role in the management of a spectrum of urological disease. [81]…”