UROLOGICAL SURVEY   ( Download pdf )

 

RECONSTRUCTIVE UROLOGY

A collagen matrix derived from bladder can be used to engineer smooth muscle tissue
Kim BS, Atala A, Yoo JJ
Department of Bioengineering, Hanyang University, Seoul, South Korea
World J Urol. 2008 Jul 2 [Epub ahead of print]

  • We have previously demonstrated that a collagen matrix derived from lamina propria, commonly known as bladder submucosa (BSM matrix), is a suitable biomaterial for several urologic applications, including reconstruction of the bladder and urethra in experimental models and clinical trials. In the present study, we evaluated the physical properties of BSM as well as its biocompatibility, cellular interactions, and ability to support the formation of functional tissue in order to determine whether this biomaterial could serve as a matrix for urinary smooth muscle tissue engineering. BSM matrix resembles the extracellular matrix of bladder submucosa in its native structure, composition, and mechanical properties. BSM matrix supported normal mitochondrial metabolic and proliferative functions of human urinary smooth muscle cells and did not induce cytotoxic effects in vitro. When implanted in vivo, BSM matrix promoted the regeneration of urinary smooth muscle tissues with contractility, which is a smooth muscle-specific tissue function. These results suggest that BSM matrix would be a useful biomaterial for urinary smooth muscle reconstruction.

  • Editorial Comment
    Using scaffolds to regenerate tissue especially in the urological field has been the aim for the last decade. Which scaffold might be the best still seems to be not clear. The paper of Kim et al. investigated the native structure of Bladder Submucosa Matrix (BSM), seeded with smooth muscle cells as a composition and its mechanical properties. Compared to previous publications the extended investigation was performed in a tissue-engineered seeded fashion, but as Piechota et al. (1) previously demonstrated (and further investigated by Dahms et al. (2), the acellular Bladder Matrix Graft (BMG) fully regenerated and functioned as native bladder tissue.
    The use of organ-specific scaffolds was extended to other urological organs such as urethra and ureter (3). However, the use of SIS® by Cook in the context of pre-seeding scaffold did not always demonstrate the expected success (4). Through the investigation of BSM, Kim et al. compared unseeded scaffolds; they found that BSM demonstrated a faster functional regeneration, thus underlining, depending on its thickness, that an organ-specific scaffold might be more favorable (5).

References
1. Piechota HJ, Gleason CA, Dahms SE, Dahiya R, Nunes LS, Lue TF, et al.: Bladder acellular matrix graft: in vivo functional properties of the regenerated rat bladder. Urol Res. 1999; 27: 206-13.
2. Dahms SE, Piechota HJ, Dahiya R, Gleason CA, Hohenfellner M, Tanagho EA: Bladder acellular matrix graft in rats: its neurophysiologic properties and mRNA expression of growth factors TGF-alpha and TGF-beta. Neurourol Urodyn. 1998; 17: 37-54.
3. Sievert KD, Tanagho EA: Organ-specific acellular matrix for reconstruction of the urinary tract. World J Urol. 2000; 18: 19-25.
4. Feil G, Christ-Adler M, Maurer S, Corvin S, Rennekampff HO, Krug J, et al.: Investigations of urothelial cells seeded on commercially available small intestine submucosa. Eur Urol. 2006; 50: 1330-7.
5. Sievert KD, Wefer J, Bakircioglu ME, Nunes L, Dahiya R, Tanagho EA: Heterologous acellular matrix graft for reconstruction of the rabbit urethra: histological and functional evaluation. J Urol. 2001; 165: 2096-102.

Dr. Karl-Dietrich Sievert &
Dr. Arnulf Stenzl

Department of Urology
Eberhard-Karls-University Tuebingen
Tuebingen, Germany
E-mail: arnulf.stenzl@med.uni-tuebingen.de