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Urinary Tissue Engineering: Challenges and Opportunities. Sex Med Rev 2017; 6:35-44. [PMID: 29066225 DOI: 10.1016/j.sxmr.2017.08.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 08/09/2017] [Accepted: 08/17/2017] [Indexed: 01/14/2023]
Abstract
INTRODUCTION In this review, we discuss major advancements and common challenges in constructing and regenerating a neo-urinary conduit (NUC). First, we focus on the need for regenerating the urothelium, the hallmark the urine barrier, unique to urinary tissues. Second, we focus on clinically feasible scaffolds based on decellularized matrices and molded collagen that are currently of great research interest. AIM To discuss the major advancements in constructing a tissue-engineered NUC (TE-NUC) and the challenges involved in their successful clinical translation. METHODS A comprehensive search of peer-reviewed literature from PubMed and Google Scholar on subjects related to urothelium regeneration, decellularized tissue matrices, and collagen scaffolds was conducted. MAIN OUTCOME MEASURE We evaluated the main biological and mechanical functions of urinary tissues, the need for TE implants to create a urinary diversion, the reasons for their failures in clinical settings, and the applications of decellularized tissue matrices and collagen-based molded scaffolds in their regeneration. RESULTS It is necessary to create a urine barrier that prevents urine leakage into the stroma that can cause failure of the graft. Despite the regeneration potential of the urothelium, the limited supply of healthy urothelial cells in patients with bladder cancer remains a major challenge. In this context, alternative strategies, such as transdifferentiation of cells into urothelium or engineered scaffolds based on decellularized tissues and molded collagen with robust urine barrier properties, are active areas of research. CONCLUSION There is an immediate need for developing a functional TE-NUC that can improve the quality of life of patients with bladder cancer. It is possible to achieve a TE-NUC by bioengineering an implant that has appropriate biological and mechanical properties to store and transport urine. We anticipate that future advancements in urothelium regeneration and material design will lead us closer to successful neo-urinary tissue constructs. Singh A, Bivalacqua TJ, Sopko N. Urinary Tissue Engineering: Challenges and Opportunities. Sex Med Rev 2018;6:35-44.
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Adamowicz J, Pokrywczynska M, Van Breda SV, Kloskowski T, Drewa T. Concise Review: Tissue Engineering of Urinary Bladder; We Still Have a Long Way to Go? Stem Cells Transl Med 2017; 6:2033-2043. [PMID: 29024555 PMCID: PMC6430044 DOI: 10.1002/sctm.17-0101] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Accepted: 07/18/2017] [Indexed: 12/18/2022] Open
Abstract
Regenerative medicine is a new branch of medicine based on tissue engineering technology. This rapidly developing field of science offers revolutionary treatment strategy aimed at urinary bladder regeneration. Despite many promising announcements of experimental urinary bladder reconstruction, there has been a lack in commercialization of therapies based on current investigations. This is due to numerous obstacles that are slowly being identified and precisely overcome. The goal of this review is to present the current status of research on urinary bladder regeneration and highlight further challenges that need to be gradually addressed. We put an emphasis on expectations of urologists that are awaiting tissue engineering based solutions in clinical practice. This review also presents a detailed characteristic of obstacles on the road to successful urinary bladder regeneration from urological clinician perspective. A defined interdisciplinary approach might help to accelerate planning transitional research tissue engineering focused on urinary tracts. Stem Cells Translational Medicine 2017;6:2033-2043.
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Affiliation(s)
- Jan Adamowicz
- Chair of Urology, Department of Regenerative Medicine, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz, Poland
| | - Marta Pokrywczynska
- Chair of Urology, Department of Regenerative Medicine, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz, Poland
| | | | - Tomasz Kloskowski
- Chair of Urology, Department of Regenerative Medicine, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz, Poland
| | - Tomasz Drewa
- Chair of Urology, Department of Regenerative Medicine, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz, Poland
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Zhou S, Yang R, Zou Q, Zhang K, Yin T, Zhao W, Shapter JG, Gao G, Fu Q. Fabrication of Tissue-Engineered Bionic Urethra Using Cell Sheet Technology and Labeling By Ultrasmall Superparamagnetic Iron Oxide for Full-Thickness Urethral Reconstruction. Theranostics 2017; 7:2509-2523. [PMID: 28744331 PMCID: PMC5525753 DOI: 10.7150/thno.18833] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Accepted: 04/21/2017] [Indexed: 01/18/2023] Open
Abstract
Urethral strictures remain a reconstructive challenge, due to less than satisfactory outcomes and high incidence of stricture recurrence. An “ideal” urethral reconstruction should establish similar architecture and function as the original urethral wall. We fabricated a novel tissue-engineered bionic urethras using cell sheet technology and report their viability in a canine model. Small amounts of oral and adipose tissues were harvested, and adipose-derived stem cells, oral mucosal epithelial cells, and oral mucosal fibroblasts were isolated and used to prepare cell sheets. The cell sheets were hierarchically tubularized to form 3-layer tissue-engineered urethras and labeled by ultrasmall super-paramagnetic iron oxide (USPIO). The constructed tissue-engineered urethras were transplanted subcutaneously for 3 weeks to promote the revascularization and biomechanical strength of the implant. Then, 2 cm length of the tubularized penile urethra was replaced by tissue-engineered bionic urethra. At 3 months of urethral replacement, USPIO-labeled tissue-engineered bionic urethra can be effectively detected by MRI at the transplant site. Histologically, the retrieved bionic urethras still displayed 3 layers, including an epithelial layer, a fibrous layer, and a myoblast layer. Three weeks after subcutaneous transplantation, immunofluorescence analysis showed the density of blood vessels in bionic urethra was significantly increased following the initial establishment of the constructs and was further up-regulated at 3 months after urethral replacement and was close to normal level in urethral tissue. Our study is the first to experimentally demonstrate 3-layer tissue-engineered urethras can be established using cell sheet technology and can promote the regeneration of structural and functional urethras similar to normal urethra.
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Versteegden LRM, de Jonge PKJD, IntHout J, van Kuppevelt TH, Oosterwijk E, Feitz WFJ, de Vries RBM, Daamen WF. Tissue Engineering of the Urethra: A Systematic Review and Meta-analysis of Preclinical and Clinical Studies. Eur Urol 2017; 72:594-606. [PMID: 28385451 DOI: 10.1016/j.eururo.2017.03.026] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Accepted: 03/17/2017] [Indexed: 01/31/2023]
Abstract
CONTEXT Urethra repair by tissue engineering has been extensively studied in laboratory animals and patients, but is not routinely used in clinical practice. OBJECTIVE To systematically investigate preclinical and clinical evidence of the efficacy of tissue engineering for urethra repair in order to stimulate translation of preclinical studies to the clinic. EVIDENCE ACQUISITION A systematic search strategy was applied in PubMed and EMBASE. Studies were independently screened for relevance by two reviewers, resulting in 80 preclinical and 23 clinical studies of which 63 and 13 were selected for meta-analysis to assess side effects, functionality, and study completion. Analyses for preclinical and clinical studies were performed separately. Full circumferential and inlay procedures were assessed independently. Evaluated parameters included seeding of cells and type of biomaterial. EVIDENCE SYNTHESIS Meta-analysis revealed that cell seeding significantly reduced the probability of encountering side effects in preclinical studies. Remarkably though, cells were only sparsely used in the clinic (4/23 studies) and showed no significant reduction of side effects. ln 21 out of 23 clinical studies, decellularized templates were used, while in preclinical studies other biomaterials showed promising outcomes as well. No direct comparison to current clinical practice could be made due to the limited number of randomized controlled studies. CONCLUSIONS Due to a lack of controlled (pre)clinical studies, the efficacy of tissue engineering for urethra repair could not be determined. Meta-analysis outcome measures were similar to current treatment options described in literature. Surprisingly, it appeared that favorable preclinical results, that is inclusion of cells, were not translated to the clinic. Improved (pre)clinical study designs may enhance clinical translation. PATIENT SUMMARY We reviewed all available literature on urethral tissue engineering to assess the efficacy in preclinical and clinical studies. We show that improvements to (pre)clinical study design is required to improve clinical translation of tissue engineering technologies.
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Affiliation(s)
- Luuk R M Versteegden
- Department of Biochemistry, Radboud Institute for Molecular Life Sciences, Radboud university medical center, Nijmegen, The Netherlands
| | - Paul K J D de Jonge
- Department of Urology, Radboud Institute for Molecular Life Sciences, Radboud university medical center, Nijmegen, The Netherlands
| | - Joanna IntHout
- Department for Health Evidence, Radboud Institute for Health Sciences, Radboud university medical center, Nijmegen, The Netherlands
| | - Toin H van Kuppevelt
- Department of Biochemistry, Radboud Institute for Molecular Life Sciences, Radboud university medical center, Nijmegen, The Netherlands
| | - Egbert Oosterwijk
- Department of Urology, Radboud Institute for Molecular Life Sciences, Radboud university medical center, Nijmegen, The Netherlands
| | - Wout F J Feitz
- Department of Urology, Radboud Institute for Molecular Life Sciences, Radboud university medical center, Nijmegen, The Netherlands; Radboudumc Amalia Children's Hospital, Radboud university medical center, Nijmegen, The Netherlands
| | - Rob B M de Vries
- SYRCLE (SYstematic Review Centre for Laboratory Animal Experimentation), Department for Health Evidence (section HTA), Radboud Institute for Health Sciences, Radboud university medical center, Nijmegen, The Netherlands
| | - Willeke F Daamen
- Department of Biochemistry, Radboud Institute for Molecular Life Sciences, Radboud university medical center, Nijmegen, The Netherlands.
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Liu Y, Ma W, Liu B, Wang Y, Chu J, Xiong G, Shen L, Long C, Lin T, He D, Butnaru D, Alexey L, Zhang Y, Zhang D, Wei G. Urethral reconstruction with autologous urine-derived stem cells seeded in three-dimensional porous small intestinal submucosa in a rabbit model. Stem Cell Res Ther 2017; 8:63. [PMID: 28279224 PMCID: PMC5345143 DOI: 10.1186/s13287-017-0500-y] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2016] [Revised: 12/31/2016] [Accepted: 02/09/2017] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Urethral reconstruction is one of the great surgical challenges for urologists. A cell-based tissue-engineered urethra may be an alternative for patients who have complicated long strictures and need urethral reconstruction. Here, we demonstrated the feasibility of using autologous urine-derived stem cells (USCs) seeded on small intestinal submucosa (SIS) to repair a urethral defect in a rabbit model. METHODS Autologous USCs were obtained and characterized, and their capacity to differentiate into urothelial cells (UCs) and smooth muscle cells (SMCs) was tested. Then, USCs were labeled with PKH67, seeded on SIS, and transplanted to repair a urethral defect. The urethral defect model was surgically established in New Zealand white male rabbits. A ventral urethral gap was created, and the urethral mucosa was completely removed, with a mean rabbit penile urethra length of 2 cm. The urethral mucosal defect was repaired with a SIS scaffold (control group: SIS with no USCs; experimental group: autologous USC-seeded SIS; n = 12 for each group). A series of tests, including a retrograde urethrogram, histological analysis, and immunofluorescence, was undertaken 2, 3, 4, and 12 weeks after the operation to evaluate the effect of the autologous USCs on urethral reconstruction. RESULTS Autologous USCs could be easily collected and induced to differentiate into UCs and SMCs. In addition, the urethral caliber, speed of urothelial regeneration, content of smooth muscle, and vessel density were significantly improved in the group with autologous USC-seeded SIS. Moreover, inflammatory cell infiltration and fibrosis were found in the control group with only SIS, but not in the experimental autologous USC-seeded SIS group. Furthermore, immunofluorescence staining demonstrated that the transplanted USCs differentiated into UCs and SMCs in vivo. CONCLUSIONS Autologous USCs can be used as an alternative cell source for cell-based tissue engineering for urethral reconstruction.
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Affiliation(s)
- Yang Liu
- Department of Urology, Children’s Hospital of Chongqing Medical University, Chongqing, 400014 China
- Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, China International Science and Technology Cooperation base of Child development and Critical Disorders, Chongqing Key Laboratory of Child Urogenital Development and Tissue Engineering, Chongqing, 400014 China
| | - Wenjun Ma
- Department of Urology, Children’s Hospital of Chongqing Medical University, Chongqing, 400014 China
- Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, China International Science and Technology Cooperation base of Child development and Critical Disorders, Chongqing Key Laboratory of Child Urogenital Development and Tissue Engineering, Chongqing, 400014 China
- Chongqing Engineering Research Center of Stem Cell Therapy, Children’s Hospital of Chongqing Medical University, Chongqing, China
| | - Bo Liu
- Department of Urology, Children’s Hospital of Chongqing Medical University, Chongqing, 400014 China
- Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, China International Science and Technology Cooperation base of Child development and Critical Disorders, Chongqing Key Laboratory of Child Urogenital Development and Tissue Engineering, Chongqing, 400014 China
| | - Yangcai Wang
- Department of Urology, Children’s Hospital of Chongqing Medical University, Chongqing, 400014 China
- Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, China International Science and Technology Cooperation base of Child development and Critical Disorders, Chongqing Key Laboratory of Child Urogenital Development and Tissue Engineering, Chongqing, 400014 China
| | - Jiaqiang Chu
- Department of Urology, Children’s Hospital of Chongqing Medical University, Chongqing, 400014 China
- Chongqing Engineering Research Center of Stem Cell Therapy, Children’s Hospital of Chongqing Medical University, Chongqing, China
| | - Geng Xiong
- Department of Urology, Children’s Hospital of Chongqing Medical University, Chongqing, 400014 China
- Wake Forest Institute for Regenerative Medicine, Wake Forest School of Medicine, Winston-Salem, NC 27101 USA
| | - Lianju Shen
- Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, China International Science and Technology Cooperation base of Child development and Critical Disorders, Chongqing Key Laboratory of Child Urogenital Development and Tissue Engineering, Chongqing, 400014 China
| | - Chunlan Long
- Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, China International Science and Technology Cooperation base of Child development and Critical Disorders, Chongqing Key Laboratory of Child Urogenital Development and Tissue Engineering, Chongqing, 400014 China
| | - Tao Lin
- Department of Urology, Children’s Hospital of Chongqing Medical University, Chongqing, 400014 China
| | - Dawei He
- Department of Urology, Children’s Hospital of Chongqing Medical University, Chongqing, 400014 China
| | - Denis Butnaru
- Research Institute for Uronephrology, Sechenov First Moscow State Medical University, Moscow, 119991 Russia
| | - Lyundup Alexey
- Biomedical Research Department of Institute of Molecular Medicine, Sechenov First Moscow State Medical University, Moscow, 119991 Russia
| | - Yuanyuan Zhang
- Wake Forest Institute for Regenerative Medicine, Wake Forest School of Medicine, Winston-Salem, NC 27101 USA
| | - Deying Zhang
- Department of Urology, Children’s Hospital of Chongqing Medical University, Chongqing, 400014 China
- Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, China International Science and Technology Cooperation base of Child development and Critical Disorders, Chongqing Key Laboratory of Child Urogenital Development and Tissue Engineering, Chongqing, 400014 China
| | - Guanghui Wei
- Department of Urology, Children’s Hospital of Chongqing Medical University, Chongqing, 400014 China
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Browne BM, Vanni AJ. Use of Alternative Techniques and Grafts in Urethroplasty. Urol Clin North Am 2017; 44:127-140. [DOI: 10.1016/j.ucl.2016.08.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Pinnagoda K, Larsson HM, Vythilingam G, Vardar E, Engelhardt EM, Thambidorai RC, Hubbell JA, Frey P. Engineered acellular collagen scaffold for endogenous cell guidance, a novel approach in urethral regeneration. Acta Biomater 2016; 43:208-217. [PMID: 27450527 DOI: 10.1016/j.actbio.2016.07.033] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Revised: 07/12/2016] [Accepted: 07/18/2016] [Indexed: 11/18/2022]
Abstract
UNLABELLED The treatment of congenital malformations or injuries of the urethra using existing autologous tissues can be associated with post-operative complications. Using rat-tail collagen, we have engineered an acellular high-density collagen tube. These tubes were made of 2 layers and they could sustain greater burst pressures than the monolayered tubes. Although it remains a weak material this 2 layered tube could be sutured to the native urethra. In 20 male New Zealand white rabbits, 2cm long grafts were sutured in place after subtotal excision of the urethra. This long-term study was performed in Lausanne (Switzerland) and in Kuala Lumpur (Malaysia). No catheter was placed post-operatively. All rabbits survived the surgical implantation. The animals were evaluated at 1, 3, 6, and 9months by contrast voiding cysto-urethrography, histological examination and immunohistochemistry. Spontaneous re-population of urothelial and smooth muscle cells on all grafts was demonstrated. Cellular organization increased with time, however, 20% of both fistula and stenosis could be observed post-operatively. This off-the shelf scaffold with a promising urethral regeneration has a potential for clinical application. STATEMENT OF SIGNIFICANCE In this study we have tissue engineered a novel cell free tubular collagen based scaffold and used it as a urethral graft in a rabbit model. The novelty of our technique is that the tube can be sutured. Testing showed better burst pressures and the grafts could then be successfully implanted after a urethral excision. This long term study demonstrated excellent biocompatibility of the 2cm graft and gradual regeneration with time, challenging the current literature. Finally, the main impact is that we describe an off-the-shelf and cost-effective product with comparable surgical outcome to the cellular grafts.
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Affiliation(s)
- Kalitha Pinnagoda
- Department of Pediatric Surgery, Centre Hospitalier Universitaire Vaudois (CHUV), Lausanne, Switzerland; Laboratory for Regenerative Medicine and Pharmacobiology, Institute for Bioengineering, School of Life Sciences and School of Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Hans M Larsson
- Department of Pediatrics, Centre Hospitalier Universitaire Vaudois (CHUV), Lausanne, Switzerland; Laboratory for Regenerative Medicine and Pharmacobiology, Institute for Bioengineering, School of Life Sciences and School of Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Ganesh Vythilingam
- Department of Surgery, Faculty of Medicine, University Malaya, Kuala Lumpur, Malaysia; Laboratory for Regenerative Medicine and Pharmacobiology, Institute for Bioengineering, School of Life Sciences and School of Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Elif Vardar
- Laboratory for Regenerative Medicine and Pharmacobiology, Institute for Bioengineering, School of Life Sciences and School of Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Eva-Maria Engelhardt
- Laboratory for Regenerative Medicine and Pharmacobiology, Institute for Bioengineering, School of Life Sciences and School of Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | | | - Jeffrey A Hubbell
- Laboratory for Regenerative Medicine and Pharmacobiology, Institute for Bioengineering, School of Life Sciences and School of Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland; Institute for Molecular Engineering, University of Chicago, Chicago, IL, USA
| | - Peter Frey
- Laboratory for Regenerative Medicine and Pharmacobiology, Institute for Bioengineering, School of Life Sciences and School of Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
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Ramsay S, Ringuette-Goulet C, Langlois A, Bolduc S. Clinical challenges in tissue-engineered urethral reconstruction. Transl Androl Urol 2016; 5:267-70. [PMID: 27141456 PMCID: PMC4837313 DOI: 10.21037/tau.2016.01.11] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Sophie Ramsay
- 1 Centre de Recherche en Organogénèse Expérimentale/LOEX, Division of Regenerative Medicine, CHU de Québec Research Center/FRQS, Québec City, QC, Canada ; 2 Department of Surgery, Faculty of Medicine, Laval University, Quebec City, QC, Canada
| | - Cassandra Ringuette-Goulet
- 1 Centre de Recherche en Organogénèse Expérimentale/LOEX, Division of Regenerative Medicine, CHU de Québec Research Center/FRQS, Québec City, QC, Canada ; 2 Department of Surgery, Faculty of Medicine, Laval University, Quebec City, QC, Canada
| | - Alexandre Langlois
- 1 Centre de Recherche en Organogénèse Expérimentale/LOEX, Division of Regenerative Medicine, CHU de Québec Research Center/FRQS, Québec City, QC, Canada ; 2 Department of Surgery, Faculty of Medicine, Laval University, Quebec City, QC, Canada
| | - Stéphane Bolduc
- 1 Centre de Recherche en Organogénèse Expérimentale/LOEX, Division of Regenerative Medicine, CHU de Québec Research Center/FRQS, Québec City, QC, Canada ; 2 Department of Surgery, Faculty of Medicine, Laval University, Quebec City, QC, Canada
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Lv X, Li Z, Chen S, Xie M, Huang J, Peng X, Yang R, Wang H, Xu Y, Feng C. Structural and functional evaluation of oxygenating keratin/silk fibroin scaffold and initial assessment of their potential for urethral tissue engineering. Biomaterials 2016; 84:99-110. [DOI: 10.1016/j.biomaterials.2016.01.032] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Revised: 12/31/2015] [Accepted: 01/15/2016] [Indexed: 11/17/2022]
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Xue JD, Gao J, Fu Q, Feng C, Xie H. Seeding cell approach for tissue-engineered urethral reconstruction in animal study: A systematic review and meta-analysis. Exp Biol Med (Maywood) 2016; 241:1416-28. [PMID: 27022134 DOI: 10.1177/1535370216640148] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 02/22/2016] [Indexed: 11/16/2022] Open
Abstract
We systematically reviewed published preclinical studies to evaluate the effectiveness of cell-seeded tissue engineering approach for urethral reconstruction in an animal model. The outcomes were summarized by success factors in the animal experiments, which evaluate the possibility and feasibility of a clinical application in the future. Preclinical studies of tissue engineering approaches for urethral reconstruction were identified through a systematic search in PubMed, Embase, and Biosis Previews (web of science SP) databases for studies published from 1 January 1980 to 23 November 2014. Primary studies were included if urethral reconstruction was performed using a tissue-engineered biomaterial in any animal species (with the experiment group being a cell-seeded scaffold and the control group being a cell-free scaffold) with histology and urethrography as the outcome measure. A total of 15 preclinical studies were included in our meta-analysis. The histology and urethrography outcome between the experimental and control groups were considered to be the most clinically relevant. Through this systematic approach, our outcomes suggested that applying the cell-seeded biomaterial in creating a neo-urethra was stable and effective. And multi-type cells including epithelial cells as well as smooth muscle cells or fibroblasts seemed to be a better strategy. Stem cells, especially after epithelial differentiation, could be a promising choice for future researches.
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Affiliation(s)
- Jing-Dong Xue
- Department of Urology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233, China
| | - Jing Gao
- Department of Obstetrics & Gynecology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Qiang Fu
- Department of Urology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233, China
| | - Chao Feng
- Department of Urology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233, China
| | - Hong Xie
- Department of Urology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233, China
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Campos-Juanatey F, Bugeja S, Ivaz SL, Frost A, Andrich DE, Mundy AR. Management of penile urethral strictures: Challenges and future directions. World J Clin Urol 2016; 5:1-10. [DOI: 10.5410/wjcu.v5.i1.1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 12/15/2015] [Accepted: 02/24/2016] [Indexed: 02/06/2023] Open
Abstract
The anatomy of the penile urethra presents additional challenges when compared to other urethral segments during open stricture surgery particularly because of its unsuitability for excision and primary anastomosis and its relatively deficient corpus spongiosum. Stricture aetiology, location, length and previous surgical intervention remain the primary factors influencing the choice of penile urethroplasty technique. We have identified what we feel are the most important challenges and controversies in penile urethral stricture reconstruction, namely the use of flaps vs grafts, use of skin or oral mucosal tissue for augmentation/substitution and when a single or a staged approach is indicated to give the best possible outcome. The management of more complex cases such as pan-urethral lichen-sclerosus strictures and hypospadias “cripples” is outlined and potential developments for the future are presented.
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Development of a cell-seeded modified small intestinal submucosa for urethroplasty. Heliyon 2016; 2:e00087. [PMID: 27441265 PMCID: PMC4946073 DOI: 10.1016/j.heliyon.2016.e00087] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 01/28/2016] [Accepted: 03/01/2016] [Indexed: 11/21/2022] Open
Abstract
OBJECTIVE To explore the feasibility of a modified 3D porous small intestinal submucosa (SIS) scaffold seeded with urothelial cells (UC) for surgical reconstruction in a rabbit model. MATERIAL AND METHODS Eighteen New England white male rabbits were divided into three groups and a 0.8 × 1.5 cm(2) section of the anterior urethral mucosa was removed from each animal. Ventral onlay urethroplasty was performed with a 1.0 × 1.7 cm(2) SIS scaffold that was either cell-seeded and treated with 5% peracetic acid (PAA) (n = 6), or cell-seeded and untreated (n = 6), or unseeded and treated with 5% PAA (n = 6). Animals were sacrificed at 6 months post-repair and retrograde urethrography and histological analyses performed. RESULTS In animals implanted with cell-seeded and PAA treated SIS scaffolds, urethrography showed wide-caliber urethra without any signs of stricture or fistulae, and histological analyses confirmed a complete urethral structure. In contrast, ulceration and fistula occurred in the reconstructed urethra of animals implanted with cell-seeded but untreated SIS scaffolds, and evident stricture was present in the unseeded, PAA treated group. Histological analyses demonstrated less urothelial coverage and smooth muscle in the cell-seeded and untreated SIS scaffold group, and serious fibrosis formation occurred in the unseeded, treated group. CONCLUSIONS A modified 3D porous SIS scaffold seeded with UC and treated with PAA produces better urethroplasty results than cell-seeded untreated SIS scaffolds, or unseeded PAA treated SIS scaffolds.
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Atala A, Danilevskiy M, Lyundup A, Glybochko P, Butnaru D, Vinarov A, Yoo JJ. The potential role of tissue-engineered urethral substitution: clinical and preclinical studies. J Tissue Eng Regen Med 2015; 11:3-19. [PMID: 26631921 DOI: 10.1002/term.2112] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Revised: 10/01/2015] [Accepted: 10/15/2015] [Indexed: 01/10/2023]
Abstract
Urethral strictures and anomalies remain among the difficult problems in urology, with urethroplasty procedures being the most effective treatment options. The two major types of urethroplasty are anastomotic urethroplasty and widening the urethral lumen using flaps or grafts (i.e. substitution urethroplasty). However, no ideal material for the latter has been found so far. Designing and selecting such a material is a necessary and challenging endeavour, driving the need for further bioengineered urethral tissue research. This article reviews currently available studies on the potentialities of tissue engineering in urethral reconstruction, in particular those describing the use of both acellular and recellularized tissue-engineered constructs in animal and human models. Possible future developments in this field are also discussed. Copyright © 2015 John Wiley & Sons, Ltd.
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Affiliation(s)
- Anthony Atala
- Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Mikhail Danilevskiy
- Research Institute of Uronephrology and Reproductive Health, I. M. Sechenov First Moscow State Medical University, Moscow, Russian Federation
| | - Alexey Lyundup
- Research Institute of Molecular Medicine, I. M. Sechenov First Moscow State Medical University, Moscow, Russian Federation
| | - Petr Glybochko
- I. M. Sechenov First Moscow State Medical University, Moscow, Russian Federation
| | - Denis Butnaru
- Research Institute of Uronephrology and Reproductive Health, I. M. Sechenov First Moscow State Medical University, Moscow, Russian Federation
| | - Andrey Vinarov
- Research Institute of Uronephrology and Reproductive Health, I. M. Sechenov First Moscow State Medical University, Moscow, Russian Federation
| | - James J Yoo
- Wake Forest Institute for Regenerative Medicine, Wake Forest University, Winston-Salem, NC, USA
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Huang JW, Lv XG, Li Z, Song LJ, Feng C, Xie MK, Li C, Li HB, Wang JH, Zhu WD, Chen SY, Wang HP, Xu YM. Urethral reconstruction with a 3D porous bacterial cellulose scaffold seeded with lingual keratinocytes in a rabbit model. ACTA ACUST UNITED AC 2015; 10:055005. [PMID: 26358641 DOI: 10.1088/1748-6041/10/5/055005] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The goal of this study was to evaluate the effects of urethral reconstruction with a three-dimensional (3D) porous bacterial cellulose (BC) scaffold seeded with lingual keratinocytes in a rabbit model. A novel 3D porous BC scaffold was prepared by gelatin sponge interfering in the BC fermentation process. Rabbit lingual keratinocytes were isolated, expanded, and seeded onto 3D porous BC. BC alone (group 1, N = 10), 3D porous BC alone (group 2, N = 10), and 3D porous BC seeded with lingual keratinocytes (group 3, N = 10) were used to repair rabbit ventral urethral defects (2.0 × 0.8 cm). Scanning electron microscopy revealed that BC consisted of a compact laminate while 3D porous BC was composed of a porous sheet buttressed by a dense outer layer. The average pore diameter and porosity of the 3D porous BC were 4.23 ± 1.14 μm and 67.00 ± 6.80%, respectively. At 3 months postoperatively, macroscopic examinations and retrograde urethrograms of urethras revealed that all urethras maintained wide calibers in group 3. Strictures were found in all rabbits in groups 1 and 2. Histologically, at 1 month postoperatively, intact epithelium occurred in group 3, and discontinued epithelium was found in groups 1 and 2. However, groups 2 and 3 exhibited similar epithelial regeneration, which was superior to that of group 1 at 3 months (p < 0.05). Comparisons of smooth muscle content and endothelia density among the three groups revealed a significant increase at each time point (p < 0.05). Our results demonstrated that 3D porous BC seeded with lingual keratinocytes enhanced urethral tissue regeneration. 3D porous BC could potentially be used as an optimized scaffold for urethral reconstruction.
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Affiliation(s)
- Jian-Wen Huang
- Department of Urology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yishan Road, Shanghai, 200233, People's Republic of China
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65
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Scully BB, Fan C, Grigoryan B, Jacot JG, Vick GW, Kim JJ, Fraser CD, Grande-Allen KJ, Morales DLS. Remodeling of ECM patch into functional myocardium in an ovine model: A pilot study. J Biomed Mater Res B Appl Biomater 2015; 104:1713-1720. [PMID: 26348258 DOI: 10.1002/jbm.b.33484] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Revised: 06/03/2015] [Accepted: 07/02/2015] [Indexed: 11/09/2022]
Abstract
BACKGROUND Previous studies have demonstrated that surgical patches comprised of small intestinal submucosa-derived extracellular matrix (ECM) have biological remodeling potential. This pilot study investigated histological, mechanical, and bioelectrical properties of an ECM patch implanted in the ovine right-ventricular outflow tract (RVOT). MATERIALS AND METHODS ECM patches (2 × 2 cm2 ) were implanted in four Western Range sheep (wether males, 37-49 kg, age <1 year) and explanted at 5 months (n = 2) and 8 months (n = 2). In vivo analysis included epicardial echocardiography and contact electrical mapping. Optical mapping was used to map electrical activity of two hearts on a Langendorff preparation. Mechanical testing quantified stiffness. Histological stains characterized structure, neovascularization, and calcification; immunohistochemistry (IHC) assessed cell phenotype. RESULTS In vivo analysis showed that ECM patch tissue was contractile by M-mode and two-dimensional echocardiographic evaluation. In vivo electrical mapping, and optical mapping confirmed that ECM conducted an organized electrical signal. Mechanical testing of native and ECM patched RVOT tissue showed an elastic modulus of the implanted patch comparable to native tissue stiffness. CONCLUSIONS At 5 and 8 months, the ECM had undergone extracellular matrix remodeling and neovascularization without calcification. The ECM was populated with locally aligned muscle cells positive for sarcomeric alpha-actinin, CD45, and troponin I and T. In sheep, the ECM patch appears to have the potential of remodeling to resemble native, functional ventricular tissue as evidenced by histological, mechanical, and electrical properties. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1713-1720, 2016.
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Affiliation(s)
- Brandi B Scully
- Michael E. DeBakey Department of Surgery, Division of Congenital Heart Surgery, Baylor College of Medicine, Houston, Texas.,Department of Surgery, Division of Congenital Heart Surgery, Texas Children's Hospital, Houston, Texas.,Department of Bioengineering, Rice University, Houston, Texas
| | - Christopher Fan
- Department of Bioengineering, Rice University, Houston, Texas
| | | | - Jeffrey G Jacot
- Department of Surgery, Division of Congenital Heart Surgery, Texas Children's Hospital, Houston, Texas.,Department of Bioengineering, Rice University, Houston, Texas
| | - G W Vick
- Department of Surgery, Division of Congenital Heart Surgery, Texas Children's Hospital, Houston, Texas.,Department of Pediatrics, Baylor College of Medicine, Houston, Texas
| | - Jeffrey J Kim
- Department of Surgery, Division of Congenital Heart Surgery, Texas Children's Hospital, Houston, Texas.,Department of Pediatrics, Baylor College of Medicine, Houston, Texas
| | - Charles D Fraser
- Michael E. DeBakey Department of Surgery, Division of Congenital Heart Surgery, Baylor College of Medicine, Houston, Texas.,Department of Surgery, Division of Congenital Heart Surgery, Texas Children's Hospital, Houston, Texas.,Department of Bioengineering, Rice University, Houston, Texas.,Department of Pediatrics, Baylor College of Medicine, Houston, Texas
| | | | - David L S Morales
- Department of Cardiothoracic Surgery, Cincinnati Children's Hospital, Cincinnati, Ohio.
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Jia W, Tang H, Wu J, Hou X, Chen B, Chen W, Zhao Y, Shi C, Zhou F, Yu W, Huang S, Ye G, Dai J. Urethral tissue regeneration using collagen scaffold modified with collagen binding VEGF in a beagle model. Biomaterials 2015; 69:45-55. [PMID: 26280949 DOI: 10.1016/j.biomaterials.2015.08.009] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Revised: 08/01/2015] [Accepted: 08/04/2015] [Indexed: 01/02/2023]
Abstract
Extensive urethral defects have a serious impact on quality of life, and treatment is challenging. A shortage of material for reconstruction is a key limitation. Improving the properties of biomaterials and making them suitable for urethral reconstruction will be helpful. Previously, we constructed a fusion protein, collagen-binding VEGF (CBD-VEGF), which can bind to collagen scaffold, stimulate cell proliferation, and promote angiogenesis and tissue regeneration. We proposed that CBD-VEGF could improve the performance of collagen in reconstruction of extensive urethral defects. Our results showed that collagen scaffolds modified with CBD-VEGF could promote urethral tissue regeneration and improve the function of the neo-urethra in a beagle extensive urethral defect model. Thus, modifying biomaterials with bioactive factors provides an alternative strategy for the production of suitable biomaterials for urethral reconstruction.
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Affiliation(s)
- Weisheng Jia
- Department of Urology, Center of Nephrology, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, China
| | - He Tang
- Department of Chemical-defence Medicine, College of Preventive Medicine, Third Military Medical University, Chongqing 400038, China
| | - Jianjian Wu
- Department of Urology, Center of Nephrology, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, China
| | - Xianglin Hou
- Institute of Combined Injury, State Key Laboratory of Trauma, Burns and Combined Injury, Chongqing Engineering Research Center for Nanomedicine, College of Preventive Medicine, Third Military Medical University, Chongqing 400038, China; State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100190, China
| | - Bing Chen
- Institute of Combined Injury, State Key Laboratory of Trauma, Burns and Combined Injury, Chongqing Engineering Research Center for Nanomedicine, College of Preventive Medicine, Third Military Medical University, Chongqing 400038, China; State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100190, China
| | - Wei Chen
- Department of Urology, Center of Nephrology, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, China
| | - Yannan Zhao
- Institute of Combined Injury, State Key Laboratory of Trauma, Burns and Combined Injury, Chongqing Engineering Research Center for Nanomedicine, College of Preventive Medicine, Third Military Medical University, Chongqing 400038, China; State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100190, China
| | - Chunying Shi
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100190, China
| | - Feng Zhou
- Department of Urology, Center of Nephrology, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, China
| | - Wei Yu
- Department of Urology, Center of Nephrology, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, China
| | - Shengquan Huang
- Department of Urology, Center of Nephrology, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, China
| | - Gang Ye
- Department of Urology, Center of Nephrology, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, China.
| | - Jianwu Dai
- Institute of Combined Injury, State Key Laboratory of Trauma, Burns and Combined Injury, Chongqing Engineering Research Center for Nanomedicine, College of Preventive Medicine, Third Military Medical University, Chongqing 400038, China; State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100190, China.
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67
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Lv XG, Feng C, Fu Q, Xie H, Wang Y, Huang JW, Xie MK, Atala A, Xu YM, Zhao WX. Comparative study of different seeding methods based on a multilayer SIS scaffold: Which is the optimal procedure for urethral tissue engineering? J Biomed Mater Res B Appl Biomater 2015; 104:1098-108. [DOI: 10.1002/jbm.b.33460] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Revised: 04/27/2015] [Accepted: 05/13/2015] [Indexed: 12/11/2022]
Affiliation(s)
- Xiang-Guo Lv
- Department of Urology; Shanghai Jiao Tong University Affiliated Sixth People's Hospital; Shanghai People's Republic of China
| | - Chao Feng
- Department of Urology; Shanghai Jiao Tong University Affiliated Sixth People's Hospital; Shanghai People's Republic of China
| | - Qiang Fu
- Department of Urology; Shanghai Jiao Tong University Affiliated Sixth People's Hospital; Shanghai People's Republic of China
| | - Hong Xie
- Department of Urology; Shanghai Jiao Tong University Affiliated Sixth People's Hospital; Shanghai People's Republic of China
| | - Ying Wang
- Department of Urology; Shanghai Jiao Tong University Affiliated Sixth People's Hospital; Shanghai People's Republic of China
| | - Jian-Wen Huang
- Department of Urology; Shanghai Jiao Tong University Affiliated Sixth People's Hospital; Shanghai People's Republic of China
| | - Min-Kai Xie
- Department of Urology; Shanghai Jiao Tong University Affiliated Sixth People's Hospital; Shanghai People's Republic of China
| | - Anthony Atala
- Wake Forest Institute for Regenerative Medicine, Wake Forest University; Winston-Salem North Carolina
| | - Yue-Min Xu
- Department of Urology; Shanghai Jiao Tong University Affiliated Sixth People's Hospital; Shanghai People's Republic of China
| | - Wei-Xin Zhao
- Wake Forest Institute for Regenerative Medicine, Wake Forest University; Winston-Salem North Carolina
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68
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Tissue engineering in urothelium regeneration. Adv Drug Deliv Rev 2015; 82-83:64-8. [PMID: 25477302 DOI: 10.1016/j.addr.2014.11.021] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Revised: 11/04/2014] [Accepted: 11/24/2014] [Indexed: 12/12/2022]
Abstract
The development of therapeutic treatments to regenerate urothelium, manufacture tissue equivalents or neourethras for in-vivo application is a significant challenge in the field of tissue engineering. Many studies have focused on urethral defects that, in most cases, inadequately address current therapies. This article reviews the primary tissue engineering strategies aimed at the clinical requirements for urothelium regeneration while concentrating on promising investigations in the use of grafts, cellular preparations, as well as seeded or unseeded natural and synthetic materials. Despite significant progress being made in the development of scaffolds and matrices, buccal mucosa transplants have not been replaced. Recently, graft tissues appear to have an advantage over the use of matrices. These therapies depend on cell isolation and propagation in vitro that require, not only substantial laboratory resources, but also subsequent surgical implant procedures. The choice of the correct cell source is crucial when determining an in-vivo application because of the risks of tissue changes and abnormalities that may result in donor site morbidity. Addressing an appropriately-designed animal model and relevant regulatory issues is of fundamental importance for the principal investigators when a therapy using cellular components has been developed for clinical use.
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69
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Ribeiro-Filho LA, Sievert KD. Acellular matrix in urethral reconstruction. Adv Drug Deliv Rev 2015; 82-83:38-46. [PMID: 25477304 DOI: 10.1016/j.addr.2014.11.019] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Revised: 11/21/2014] [Accepted: 11/24/2014] [Indexed: 01/10/2023]
Abstract
The treatment of severe urethral stenosis has always been a challenge even for skilled urologists. Classic urethroplasty, skin flaps and buccal mucosa grafting may not be used for long and complex strictures. In the quest for an ideal urethral substitute, acellular scaffolds have demonstrated the ability to induce tissue regeneration layer by layer. After several experimental studies, the use of acellular matrices for urethral reconstruction has become a clinical reality over the last decade. In this review we analyze advantages and limitations of both biological and polymeric scaffolds that have been reported in experimental and human studies. Important aspects such as graft extension, surgical technique and cell-seeding versus cell-free grafts will be discussed.
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Kloskowski T, Pokrywczyńska M, Drewa T. Artificial urinary conduit construction using tissue engineering methods. Cent European J Urol 2014; 68:109-14. [PMID: 25914849 PMCID: PMC4408386 DOI: 10.5173/ceju.2015.01.448] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Revised: 09/12/2014] [Accepted: 11/16/2014] [Indexed: 11/24/2022] Open
Abstract
Introduction Incontinent urinary diversion using an ileal conduit is the most popular method used by urologists after bladder cystectomy resulting from muscle invasive bladder cancer. The use of gastrointestinal tissue is related to a series of complications with the necessity of surgical procedure extension which increases the time of surgery. Regenerative medicine together with tissue engineering techniques gives hope for artificial urinary conduit construction de novo without affecting the ileum. Material and methods In this review we analyzed history of urinary diversion together with current attempts in urinary conduit construction using tissue engineering methods. Based on literature and our own experience we presented future perspectives related to the artificial urinary conduit construction. Results A small number of papers in the field of tissue engineered urinary conduit construction indicates that this topic requires more attention. Three main factors can be distinguished to resolve this topic: proper scaffold construction along with proper regeneration of both the urothelium and smooth muscle layers. Conclusions Artificial urinary conduit has a great chance to become the first commercially available product in urology constructed by regenerative medicine methods.
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Affiliation(s)
- Tomasz Kloskowski
- Chair of Regenerative Medicine, Department of Tissue Engineering, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz, Poland
| | - Marta Pokrywczyńska
- Chair of Regenerative Medicine, Department of Tissue Engineering, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz, Poland
| | - Tomasz Drewa
- Chair of Regenerative Medicine, Department of Tissue Engineering, Collegium Medicum, Nicolaus Copernicus University, Bydgoszcz, Poland ; Nicolaus Copernicus Hospital in Toruń, Department of General and Oncologic Urology, Toruń, Poland
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71
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Huang JW, Xie MK, Zhang Y, Wei GJ, Li X, Li HB, Wang JH, Zhu WD, Li C, Xu YM, Song LJ. Reconstruction of Penile Urethra With the 3-Dimensional Porous Bladder Acellular Matrix in a Rabbit Model. Urology 2014; 84:1499-505. [DOI: 10.1016/j.urology.2014.07.044] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Revised: 07/24/2014] [Accepted: 07/27/2014] [Indexed: 10/24/2022]
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Engel O, de Petriconi R, Volkmer BG, Gust KM, Mani J, Haferkamp A, Hautmann RE, Bartsch G. The feasibility of ureteral tissue engineering using autologous veins: an orthotopic animal model with long term results. J Negat Results Biomed 2014; 13:17. [PMID: 25381044 PMCID: PMC4304067 DOI: 10.1186/1477-5751-13-17] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Accepted: 10/23/2014] [Indexed: 11/12/2022] Open
Abstract
Background In an earlier study we demonstrated the feasibility to create tissue engineered venous scaffolds in vitro and in vivo. In this study we investigated the use of tissue engineered constructs for ureteral replacement in a long term orthotopic minipig model. In many different projects well functional ureretal tissue was established using tissue engineering in animals with short-time follow up (12 weeks). Therefore urothelial cells were harvested from the bladder, cultured, expanded in vitro, labelled with fluorescence and seeded onto the autologous veins, which were harvested from animals during a second surgery. Three days after cell seeding the right ureter was replaced with the cell-seeded matrices in six animals, while further 6 animals received an unseeded vein for ureteral replacement. The animals were sacrificed 12, 24, and 48 weeks after implantation. Gross examination, intravenous pyelogram (IVP), H&E staining, Trichrome Masson’s Staining, and immunohistochemistry with pancytokeratin AE1/AE3, smooth muscle alpha actin, and von Willebrand factor were performed in retrieved specimens. Results The IVP and gross examination demonstrated that no animals with tissue engineered ureters and all animals of the control group presented with hydronephrosis after 12 weeks. In the 24-week group, one tissue engineered and one unseeded vein revealed hydronephrosis. After 48 weeks all tissue engineered animals and none of the control group showed hydronephrosis on the treated side. Histochemistry and immunohistochemistry revealed a multilayer of urothelial cells attached to the seeded venous grafts. Conclusions Venous grafts may be a potential source for ureteral reconstruction. The results of so far published ureteral tissue engineering projects reveal data up to 12 weeks after implantation. Even if the animal numbers of this study are small, there is an increasing rate of hydronephrosis revealing failure of ureteral tissue engineering with autologous matrices in time points longer than 3 months after implantation. Further investigations have to prove adequate clinical outcome and appropriate functional long-term results.
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Affiliation(s)
| | | | | | | | | | | | | | - Georg Bartsch
- Department of Urology, Johann Wolfgang Goethe University, Theodor Stern Kai 7, 60486 Frankfurt, Germany.
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73
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Li CL, Liao WB, Yang SX, Song C, Li YW, Xiong YH, Chen L. Urethral reconstruction using bone marrow mesenchymal stem cell- and smooth muscle cell-seeded bladder acellular matrix. Transplant Proc 2014; 45:3402-7. [PMID: 24182824 DOI: 10.1016/j.transproceed.2013.07.055] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Revised: 07/11/2013] [Accepted: 07/30/2013] [Indexed: 01/01/2023]
Abstract
BACKGROUND Congenital or acquired abnormalities may lead to a urethral defect that often requires surgical reconstruction. The traditional methods often lead to complications, including urethrocutaneous fistulae and strictures. In this study, we proposed to construct a tissue-engineered sheet graft (TESG) using a bone marrow mesenchymal stem cell (BMSC)- and smooth muscle cell (SMC)-seeded bladder acellular matrix (BAM) for urethral reconstruction. METHODS Rabbit BMSCs and SMCs were isolated, expanded, and identified in vitro before seeding into BAM as the experimental group, whereas BAM-only was the control group. The graft was used to construct TESG for implantation into the rabbit omentum for 2 weeks before urethral reconstruction. We divided 24 male rabbits into four experimental groups six each, and six other were the control group. Histological analysis was performed at 2 weeks, 4 weeks, 8 weeks, and 16 weeks postoperatively. Retrograde urethrography was performed at 16 weeks postoperatively. RESULTS All experimental rabbits survived to they were humanly killed. At 8 weeks, there was no difference between the graft and the normal urethra with no severe shrinkage. At 8 and 16 weeks after TESG grafting in vivo, multilayer urothelium covered the graft, neovascularization was visible within the center of TESG, and organized smooth muscle bundles were present. Retrograde urethrography failed to demonstrate diverticula formation or urethral stricture. Three control rabbits died within 4 weeks postoperatively. Autopsy showed their urethras to be almost completely blocked whereas another three hosts displays urethral strictures. CONCLUSION A TESG was constructed using a BMSC- and SMC-seeded BAM for urethral reconstruction.
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Affiliation(s)
- C L Li
- Department of Urology, Renmin Hospital of Wuhan University, Wuhan, and Jingmen No. 2 People's Hospital, Jingmen, Hubei, China
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Huang GTJ, Garcia-Godoy F. Missing Concepts in De Novo Pulp Regeneration. J Dent Res 2014; 93:717-24. [PMID: 24879576 DOI: 10.1177/0022034514537829] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Accepted: 05/08/2014] [Indexed: 12/13/2022] Open
Abstract
Regenerative endodontics has gained much attention in the past decade because it offers an alternative approach in treating endodontically involved teeth. Instead of filling the canal space with artificial materials, it attempts to fill the canal with vital tissues. The objective of regeneration is to regain the tissue and restore its function to the original state. In terms of pulp regeneration, a clinical protocol that intends to reestablish pulp/dentin tissues in the canal space has been developed--termed revitalization or revascularization. Histologic studies from animal and human teeth receiving revitalization have shown that pulp regeneration is difficult to achieve. In tissue engineering, there are 2 approaches to regeneration tissues: cell based and cell free. The former involves transplanting exogenous cells into the host, and the latter does not. Revitalization belongs to the latter approach. A number of crucial concepts have not been well discussed, noted, or understood in the field of regenerative endodontics in terms of pulp/dentin regeneration: (1) critical size defect of dentin and pulp, (2) cell lineage commitment to odontoblasts, (3) regeneration vs. repair, and (4) hurdles of cell-based pulp regeneration for clinical applications. This review article elaborates on these missing concepts and analyzes them at their cellular and molecular levels, which will in part explain why the non-cell-based revitalization procedure is difficult to establish pulp/dentin regeneration. Although the cell-based approach has been proven to regenerate pulp/dentin, such an approach will face barriers--with the key hurdle being the shortage of the current good manufacturing practice facilities, discussed herein.
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Affiliation(s)
- G T-J Huang
- Department of Bioscience Research, University of Tennessee Health Science Center, College of Dentistry, Memphis, TN 38163
| | - F Garcia-Godoy
- Department of Bioscience Research, University of Tennessee Health Science Center, College of Dentistry, Memphis, TN 38163
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Sayeg K, Freitas-Filho LG, Waitzberg ÂFL, Arias VEA, Laks M, Egydio FM, Oliveira AS. Integration of collagen matrices into the urethra when implanted as onlay graft. Int Braz J Urol 2014; 39:414-23. [PMID: 23849574 DOI: 10.1590/s1677-5538.ibju.2013.03.16] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Accepted: 04/29/2013] [Indexed: 01/10/2023] Open
Abstract
OBJECTIVE To assess the integration of decellularized heterologous collagen matrices into the urethra, when implanted with no cells or when seeded with autologous smooth muscle cells. MATERIALS AND METHODS Eighteen New Zealand rabbits were randomly assigned to two groups: Group I (n = 9) - animals undergoing urethral segment resection with interposition of a patch of heterologous collagen matrix seeded with autologous smooth muscle cells; Group II (n = 9) - animals undergoing resection of a urethral segment with interposition of a decellularized heterologous collagen matrix patch. Two animals from each group were sacrificed on postoperative days seven, fourteen and twenty-eight; three animals from each group were sacrificed at the end of three postoperative months. At the end of the third month one animal from each group underwent urethroscopy for urethral integrity assessment and one animal from each group had its microcirculation image captured by a SDF device (Side-stream Dark Field - Microscan Analysis Software). One animal from each group in each euthanasia period underwent cystourethrography so as the urethra could be viewed at flow time. The matrices integration was assessed through histological examination using hematoxylin and eosin (H & E), Masson trichrome (MT), Picrosirius red and Von Willebrand staining. In a blind study with two pathologists all the slides were studied. RESULTS The matrices whether seeded or not with autologous muscle cells were able to restore the architecture of the urethra, but were eliminated from the first week on, before incorporation. Microcirculation of the neourethra, at the end of the third month, showed the same characteristics as a normal urethra in both groups of animals. CONCLUSION Natural heterologous matrices implanted in the urethra as onlay graft were not incorporated into its walls but were able to fully restore the cell architecture of the organ, regardless of being seeded or not with autologous muscle cells.
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Affiliation(s)
- Kleber Sayeg
- Department of Surgery, Federal University of Sao Paulo, Brazil
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Simaioforidis V, de Jonge P, Sloff M, Oosterwijk E, Geutjes P, Feitz WF. Ureteral Tissue Engineering: Where Are We and How to Proceed? TISSUE ENGINEERING PART B-REVIEWS 2013; 19:413-9. [DOI: 10.1089/ten.teb.2012.0737] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Vasileios Simaioforidis
- Department of Urology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Paul de Jonge
- Department of Urology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
- Technical Medicine, Faculty of Science and Technology, University of Twente, The Netherlands
| | - Marije Sloff
- Department of Urology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Egbert Oosterwijk
- Department of Urology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Paul Geutjes
- Department of Urology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - Wout F.J. Feitz
- Department of Urology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
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Tissue engineering and ureter regeneration: is it possible? Int J Artif Organs 2013; 36:392-405. [PMID: 23645581 DOI: 10.5301/ijao.5000130] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/11/2012] [Indexed: 12/11/2022]
Abstract
Large ureter damages are difficult to reconstruct. Current techniques are complicated, difficult to perform, and often associated with failures. The ureter has never been regenerated thus far. Therefore the use of tissue engineering techniques for ureter reconstruction and regeneration seems to be a promising way to resolve these problems. For proper ureter regeneration the following problems must be considered: the physiological aspects of the tissue, the type and shape of the scaffold, the type of cells, and the specific environment (urine).
This review presents tissue engineering achievements in the field of ureter regeneration focusing on the scaffold, the cells, and ureter healing.
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Li C, Xu YM, Liu ZS, Li HB. Urethral reconstruction with tissue engineering and RNA interference techniques in rabbits. Urology 2013; 81:1075-80. [PMID: 23490528 DOI: 10.1016/j.urology.2013.01.041] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2012] [Revised: 01/18/2013] [Accepted: 01/25/2013] [Indexed: 11/15/2022]
Abstract
OBJECTIVE To investigate the feasibility of replacing urinary epithelial cells with oral keratinocytes and transforming growth factor β (TGF-β)1 siRNA transfected fibroblasts seeded on bladder acellular matrix graft (BAMG) to reconstruct urethra. METHODS Autologous oral keratinocytes and TGF-β1 siRNA transfected fibroblasts were seeded onto BAMGs to obtain a tissue-engineered mucosa. The tissue-engineered mucosa was assessed using morphology and scanning electron microscopy. In 27 male rabbits, a ventral urethral mucosal defect was created. Urethroplasty was performed with autogenic oral keratinocyte and TGF-β1 siRNA transfected fibroblast-seeded BAMGs (9 rabbits, group 1), with autogenic oral keratinocyte-seeded BAMGs (9 rabbits, group 2) or with BAMGs with no cell seeding (9 rabbits, group 3). Retrograde urethrography and histological analyses were performed to evaluate the results of urethroplasty. RESULTS In vitro, oral keratinocytes and TGF-β1 siRNA transfected fibroblasts had good biocompatibility with BAMGs. In vivo, the urethra kept a wide caliber in groups 1 and 2. Strictures were observed in group 3. Histologically, the retrieved urethra in group 3 showed fibrosis and inflammation during 6 months. Stratified epithelial layer regenerated in group 2, whereas there was no evidence of formation of capillary in the epithelial lower layer during the study period. Stratified epithelial layer and formation of capillary in the epithelial lower layer were evident after 6 months in group 1. CONCLUSION Our study suggested that oral keratinocytes and TGF-β1 siRNA transfected fibroblasts could be used as a source of seed cells for urethral tissue engineering.
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Affiliation(s)
- Chao Li
- Department of Urology, Affiliated Sixth People's Hospital, Shanghai Jiaotong University, Shanghai, People's Republic of China.
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Orabi H, AbouShwareb T, Zhang Y, Yoo JJ, Atala A. Cell-seeded tubularized scaffolds for reconstruction of long urethral defects: a preclinical study. Eur Urol 2013; 63:531-8. [PMID: 22877501 PMCID: PMC3554849 DOI: 10.1016/j.eururo.2012.07.041] [Citation(s) in RCA: 82] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2012] [Accepted: 07/20/2012] [Indexed: 02/05/2023]
Abstract
BACKGROUND The treatment options for patients requiring repair of a long segment of the urethra are limited by the availability of autologous tissues. We previously reported that acellular collagen-based tubularized constructs seeded with cells are able to repair small urethral defects in a rabbit model. OBJECTIVE We explored the feasibility of engineering clinically relevant long urethras for surgical reconstruction in a canine preclinical model. DESIGN, SETTING, AND PARTICIPANTS Autologous bladder epithelial and smooth muscle cells from 15 male dogs were grown and seeded onto preconfigured collagen-based tubular matrices (6 cm in length). The perineal urethral segment was removed in 21 male dogs. Urethroplasties were performed with tubularized collagen scaffolds seeded with cells in 15 animals. Tubularized constructs without cells were implanted in six animals. Serial urethrography and three-dimensional computed tomography (CT) scans were performed pre- and postoperatively at 1, 3, 6, and 12 mo. The animals were euthanized at their predetermined time points (three animals at 1 mo, and four at 3, 6, and 12 mo) for analyses. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS Statistical analysis of CT imaging and histology was not needed. RESULTS AND LIMITATIONS CT urethrograms showed wide-caliber urethras without strictures in animals implanted with cell-seeded matrices. The urethral segments replaced with acellular scaffolds collapsed. Gross examination of the urethral implants seeded with cells showed normal-appearing tissue without evidence of fibrosis. Histologically, an epithelial cell layer surrounded by muscle fiber bundles was observed on the cell-seeded constructs, and cellular organization increased over time. The epithelial and smooth muscle phenotypes were confirmed using antibodies to pancytokeratins AE1/AE3 and smooth muscle-specific desmin. Formation of an epithelial cell layer occurred in the unseeded constructs, but few muscle fibers formed. CONCLUSIONS Cell-seeded tubularized collagen scaffolds can be used to repair long urethral defects, whereas scaffolds without cells lead to poor tissue development and strictures. This study demonstrates that long tissue-engineered tubularized urethral segments may be used for urethroplasty in patients.
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Affiliation(s)
- Hazem Orabi
- Department of Urology and Institute for Regenerative Medicine, Wake Forest School of Medicine, Winston Salem, NC, USA
- Urology Department, Assiut University, Egypt 71516
| | - Tamer AbouShwareb
- Department of Urology and Institute for Regenerative Medicine, Wake Forest School of Medicine, Winston Salem, NC, USA
| | - Yuanyuan Zhang
- Department of Urology and Institute for Regenerative Medicine, Wake Forest School of Medicine, Winston Salem, NC, USA
| | - James J. Yoo
- Department of Urology and Institute for Regenerative Medicine, Wake Forest School of Medicine, Winston Salem, NC, USA
| | - Anthony Atala
- Department of Urology and Institute for Regenerative Medicine, Wake Forest School of Medicine, Winston Salem, NC, USA
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Henkel J, Hutmacher DW. Design and fabrication of scaffold-based tissue engineering. ACTA ACUST UNITED AC 2013. [DOI: 10.1515/bnm-2013-0021] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Yannas IV. Emerging rules for inducing organ regeneration. Biomaterials 2013; 34:321-30. [DOI: 10.1016/j.biomaterials.2012.10.006] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Accepted: 10/03/2012] [Indexed: 12/11/2022]
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De Filippo RE, Kornitzer BS, Yoo JJ, Atala A. Penile urethra replacement with autologous cell-seeded tubularized collagen matrices. J Tissue Eng Regen Med 2012; 9:257-64. [PMID: 23172803 DOI: 10.1002/term.1647] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2012] [Revised: 07/27/2012] [Accepted: 10/15/2012] [Indexed: 11/06/2022]
Abstract
Acellular collagen matrices have been used as an onlay material for urethral reconstruction. However, cell-seeded matrices have been recommended for tubularized urethral repairs. In this study we investigated whether long segmental penile urethral replacement using autologous cell-seeded tubularized collagen-based matrix is feasible. Autologous bladder epithelial and smooth muscle cells from nine male rabbits were grown and seeded onto preconfigured tubular matrices constructed from decellularized bladder matrices obtained from lamina propria. The entire anterior penile urethra was resected in 15 rabbits. Urethroplasties were performed with tubularized matrices seeded with cells in nine animals, and with matrices without cells in six. Serial urethrograms were performed at 1, 3 and 6 months. Retrieved urethral tissues were analysed using histo- and immunohistochemistry, western blot analyses and organ bath studies. The urethrograms showed that animals implanted with cell-seeded matrices maintained a wide urethral calibre without strictures. In contrast, the urethras with unseeded scaffolds collapsed and developed strictures. Histologically, a transitional cell layer surrounded by muscle was observed in the cell-seeded constructs. The epithelial and smooth muscle phenotypes were confirmed with AE1/AE3 and α-actin antibodies. Organ bath studies of the neourethras confirmed both physiological contractility and the presence of neurotransmitters. Tubularized collagen matrices seeded with autologous cells can be used successfully for long segmental penile urethra replacement, while implantation of tubularized collagen matrices without cells leads to poor tissue development and stricture formation. The cell-seeded collagen matrices are able to form new tissue, which is histologically similar to native urethra.
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Affiliation(s)
- Roger E De Filippo
- Division of Urology, Saban Research Institute, Children's Hospital Los Angeles, University of Southern California, Los Angeles, CA, USA
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Abstract
The field of tissue engineering is rapidly progressing. Much work has gone into developing a tissue engineered urethral graft. Current grafts, when long, can create initial donor site morbidity. In this article, we evaluate the progress made in finding a tissue engineered substitute for the human urethra. Researchers have investigated cell-free and cell-seeded grafts. We discuss different approaches to developing these grafts and review their reported successes in human studies. With further work, tissue engineered grafts may facilitate the management of lengthy urethral strictures requiring oral mucosa substitution urethroplasty.
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Micol LA, Arenas da Silva LF, Geutjes PJ, Oosterwijk E, Hubbell JA, Feitz WF, Frey P. In-vivo performance of high-density collagen gel tubes for urethral regeneration in a rabbit model. Biomaterials 2012; 33:7447-55. [DOI: 10.1016/j.biomaterials.2012.06.087] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2012] [Accepted: 06/28/2012] [Indexed: 11/16/2022]
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Vaegler M, Lenis AT, Daum L, Amend B, Stenzl A, Toomey P, Renninger M, Damaser MS, Sievert KD. Stem cell therapy for voiding and erectile dysfunction. Nat Rev Urol 2012; 9:435-47. [PMID: 22710667 PMCID: PMC3769422 DOI: 10.1038/nrurol.2012.111] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Voiding dysfunction comprises a variety of disorders, including stress urinary incontinence and overactive bladder, and affects millions of men and women worldwide. Erectile dysfunction (ED) also decreases quality of life for millions of men, as well as for their partners. Advanced age and diabetes are common comorbidities that can exacerbate and negatively impact upon the development of these disorders. Therapies that target the pathophysiology of these conditions to halt progression are not currently available. However, stem cell therapy could fill this therapeutic void. Stem cells can reduce inflammation, prevent fibrosis, promote angiogenesis, recruit endogenous progenitor cells, and differentiate to replace damaged cells. Adult multipotent stem cell therapy, in particular, has shown promise in case reports and preclinical animal studies. Stem cells also have a role in urological tissue engineering for ex vivo construction of bladder wall and urethral tissue (using a patient's own cells) prior to transplantation. More recent studies have focused on bioactive factor secretion and homing of stem cells. In the future, clinicians are likely to utilize allogeneic stem cell sources, intravenous systemic delivery, and ex vivo cell enhancement to treat voiding dysfunction and ED.
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Affiliation(s)
- Martin Vaegler
- Department of Urology, University of Tuebingen, Hoppe-Seyler-Strasse 3, D72076 Tuebingen, Germany
| | - Andrew T Lenis
- The Cleveland Clinic, Case Western Reserve University School of Medicine, 9500 Euclid Avenue, Cleveland, OH 44195, USA
| | - Lisa Daum
- Department of Urology, University of Tuebingen, Hoppe-Seyler-Strasse 3, D72076 Tuebingen, Germany
| | - Bastian Amend
- Department of Urology, University of Tuebingen, Hoppe-Seyler-Strasse 3, D72076 Tuebingen, Germany
| | - Arnulf Stenzl
- Department of Urology, University of Tuebingen, Hoppe-Seyler-Strasse 3, D72076 Tuebingen, Germany
| | - Patricia Toomey
- Department of Urology, University of Tuebingen, Hoppe-Seyler-Strasse 3, D72076 Tuebingen, Germany
| | - Markus Renninger
- Department of Urology, University of Tuebingen, Hoppe-Seyler-Strasse 3, D72076 Tuebingen, Germany
| | - Margot S Damaser
- The Cleveland Clinic, Case Western Reserve University School of Medicine, 9500 Euclid Avenue, Cleveland, OH 44195, USA
| | - Karl-Dietrich Sievert
- Department of Urology, University of Tuebingen, Hoppe-Seyler-Strasse 3, D72076 Tuebingen, Germany
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Gu GL, Xia SJ, Zhang J, Liu GH, Yan L, Xu ZH, Zhu YJ. Tubularized urethral replacement using tissue-engineered peritoneum-like tissue in a rabbit model. Urol Int 2012; 89:358-64. [PMID: 22797559 DOI: 10.1159/000339745] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Accepted: 05/28/2012] [Indexed: 11/19/2022]
Abstract
INTRODUCTION This study aims to investigate whether mesothelial cells could function as seed cells to construct tissue-engineered peritoneum-like tissue for urethral reconstruction in a rabbit model. MATERIALS AND METHODS Bladder acellular matrices were prepared and trimmed to 1.5 × 1 cm. Nine male rabbits underwent omentum biopsy and autologous mesothelial cells were isolated. After in vitro expansion, the cells were seeded onto the matrices and incubated for 7 days. In 18 rabbits, a pendulous urethral segment 1.5 cm long was totally excised and urethroplasty was performed with tubularized matrices seeded with cells in 9 animals and without cells in 9 as controls. Urethrography was performed at 1, 2 and 6 months postoperatively. Meanwhile, the neourethras were harvested and analyzed grossly and histologically. RESULTS Histological analysis of the cell-seeded grafts revealed a loose collagen matrix covered with a single layer of mesothelim. Serial urethrography indicated a wide urethral caliber without stricture formation in animals implanted with cell-seeded matrices, while all animals of the control group developed stricture. Histological analysis of the implanted cell-seeded matrices demonstrated a normal urethral architecture by 1 month, composed of multilayers of urothelium surrounded by smooth muscle bundles, which became increasingly organized with time. By 6 months, the neourethra could be hardly distinguished from native urethra both grossly and histologically. CONCLUSIONS Autologous mesothelial cells could be successfully used as seed cells for tubularized urethral reconstruction in male rabbits.
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Affiliation(s)
- Gang-Li Gu
- Department of Urology, Qilu Hospital, Shandong University, Jinan, China
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Fossum M, Skikuniene J, Orrego A, Nordenskjöld A. Prepubertal follow-up after hypospadias repair with autologous in vitro cultured urothelial cells. Acta Paediatr 2012; 101:755-60. [PMID: 22471328 DOI: 10.1111/j.1651-2227.2012.02659.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
AIM To evaluate the long-term effects on hypospadias repair with cultured autologous urothelial cells. METHODS From 2000 to 2002, six patients with scrotal or perineal hypospadias and pronounced chordee were treated surgically with cultured autologous urothelial cell transplants. All patients were evaluated at 6-8 years postoperatively, that is, in the prepubertal period. The outcome was assessed with respect to cosmetic appearance, voiding function, urinary flow, artificial erection, urethroscopy and biopsies. RESULTS Median follow-up time was 7.25 years. Up to date, all patients present with a good cosmetic appearance. One of the boys prefers a sitting voiding position. Urinary flow curves are bell-shaped in all but one. All have straight erections, urethroscopy reveals an even, non-hair-bearing surface on the transplanted side and 2/6 present with urothelial cells in biopsies. Limitations of this follow-up study include a small group of patients and lack of controls. However, patients with severe hypospadias have high complication rates, and our results are equal or better than expected for the phenotype. CONCLUSION Tissue engineering for severe hypospadias repair can be performed in a safe manner. The method is feasible for treatment of a selected group of hypospadias, where pronounced chordee and shortage of preputial and penile skin complicates the creation of a neourethra.
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Affiliation(s)
- Magdalena Fossum
- Department of Paediatric Surgery, Division of Urology, Astrid Lindgren Children's Hospital, Karolinska University Hospital, Stockholm, Sweden.
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Orlando G, Wood KJ, De Coppi P, Baptista PM, Binder KW, Bitar KN, Breuer C, Burnett L, Christ G, Farney A, Figliuzzi M, Holmes JH, Koch K, Macchiarini P, Mirmalek Sani SH, Opara E, Remuzzi A, Rogers J, Saul JM, Seliktar D, Shapira-Schweitzer K, Smith T, Solomon D, Van Dyke M, Yoo JJ, Zhang Y, Atala A, Stratta RJ, Soker S. Regenerative medicine as applied to general surgery. Ann Surg 2012; 255:867-80. [PMID: 22330032 PMCID: PMC3327776 DOI: 10.1097/sla.0b013e318243a4db] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The present review illustrates the state of the art of regenerative medicine (RM) as applied to surgical diseases and demonstrates that this field has the potential to address some of the unmet needs in surgery. RM is a multidisciplinary field whose purpose is to regenerate in vivo or ex vivo human cells, tissues, or organs to restore or establish normal function through exploitation of the potential to regenerate, which is intrinsic to human cells, tissues, and organs. RM uses cells and/or specially designed biomaterials to reach its goals and RM-based therapies are already in use in several clinical trials in most fields of surgery. The main challenges for investigators are threefold: Creation of an appropriate microenvironment ex vivo that is able to sustain cell physiology and function in order to generate the desired cells or body parts; identification and appropriate manipulation of cells that have the potential to generate parenchymal, stromal and vascular components on demand, both in vivo and ex vivo; and production of smart materials that are able to drive cell fate.
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Affiliation(s)
- Giuseppe Orlando
- Wake Forest Institute for Regenerative Medicine, Winston Salem, NC, USA.
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El-Tabey N, Shokeir A, Barakat N, El-Refaie H, El-Hamid MA, Gabr M. Cell-seeded tubular acellular matrix for replacing a long circumferential urethral defect in a canine model: Is it clinically applicable? Arab J Urol 2012; 10:192-8. [PMID: 26558025 PMCID: PMC4442891 DOI: 10.1016/j.aju.2012.01.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2011] [Revised: 01/29/2012] [Accepted: 01/30/2012] [Indexed: 11/30/2022] Open
Abstract
Objective To evaluate the feasibility of replacing a relatively long segment of the canine urethra by a tube of cell-seeded acellular collagen bladder matrix. Materials and methods The study included 14 female mongrel dogs in which a 3-cm segment of the whole urethral circumference was excised and replaced by a tube of acellular matrix seeded with autologous urothelial cells. The acellular matrix was obtained from the excised bladder of female donor dogs that were not included in the study. Autologous cells were obtained from the study dogs by open bladder biopsy, with subsequent in vitro expansion and cultivation. Urethroplasty was performed over a 16 F urethral catheter that was kept for 4 weeks. The dogs were killed humanely (one every week for 4 weeks and then one monthly for 10 months). After stent removal, retrograde urethrography was used each month in the living dogs. If retention occurred a urethrogram was taken and then the dog was killed humanely. All grafts from dogs were harvested and sent for histopathological examination. Results Exploration at 1, 2, 3 and 4 weeks showed progressive shrinkage in length, together with relative narrowing of the lumen. Three dogs developed retention within a week after stent removal and the other seven developed retention within 4 months. Retrograde urethrograms showed evidence of stricture and/or fistula at the graft site in all dogs. On exploration, grafts showed marked shrinkage (0.6–1.2 cm in length) with complete obliteration of their lumens. Histopathological examination showed extensive fibrosis of the matrix with no evident urothelial architecture. Conclusion Cell-seeded acellular matrix tube is insufficient to replace a 3-cm circumferential urethral defect in dogs.
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Affiliation(s)
- Nasr El-Tabey
- Urology and Nephrology Center, Mansoura University, Mansoura, Egypt
| | - Ahmed Shokeir
- Urology and Nephrology Center, Mansoura University, Mansoura, Egypt
| | - Nashwa Barakat
- Urology and Nephrology Center, Mansoura University, Mansoura, Egypt
| | - Hoda El-Refaie
- Urology and Nephrology Center, Mansoura University, Mansoura, Egypt
| | | | - Mahmoud Gabr
- Urology and Nephrology Center, Mansoura University, Mansoura, Egypt
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Abstract
Many congenital and acquired anomalies affect the genitourinary tract, necessitating surgical intervention. Among these are bladder exstrophy, hypospadias, epispadias, posterior urethral valves, myelomeningocele, bladder carcinoma, urethral stricture disease, stress urinary incontinence, pelvic organ prolapse, vesicoureteral reflux and traumatic injuries of the urinary tract. Surgical repair of these conditions often utilizes skin, oral mucosa or bowel autograft or xenograft material to replace missing tissue or to augment inadequate tissues. These materials are often sufficient to restore the basic anatomy of the organ to which they are being grafted, but they usually do not completely restore normal function. In addition, postoperative complications are common, especially in the case of bladder augmentation or neobladder creation with autologous bowel. The complications and inherent limitations of these procedures may be mitigated by the availability of alternative tissue sources. Therefore, there has been a great deal of interest in developing tissues engineered from autologous materials, such as mature bladder cells, bone marrow-derived stem cells and adipose tissue. Ideally, an engineered tissue would restore or preserve the normal function of the organ it is augmenting or replacing. In addition, the engineered tissue should be nonimmunogenic to minimize rejection or foreign-body reactions. For the purposes of this article, we will focus on selection of scaffolding materials, selection of cell sources, and the current applications and potential future roles of tissue engineering in urology.
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Xu Y, Fu W, Li G, Shi J, Tan H, Hu K, Cui F, Lin Q, Zhang X. Autologous urothelial cells transplantation onto a prefabricated capsular stent for tissue engineered ureteral reconstruction. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2012; 23:1119-1128. [PMID: 22382733 DOI: 10.1007/s10856-012-4583-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2011] [Accepted: 02/06/2012] [Indexed: 05/31/2023]
Abstract
In this study, we have fabricated an artificial ureter by transplantation of in vitro-expanded urothelial cells onto an in vivo-prefabricated capsular stent using tissue engineering methods. Spiral poly (L-lactic acid) (PLLA) stents were transplanted into the subcutaneous of Wistar rats for a period of 1, 2 or 3 weeks to induce the formation of connective tissue capsules on their surfaces. The capsular PLLA stents were then decellularized and further recellularized with bladder epithelial cells to fabricate artificial ureters. The results showed that the entrapped cells in all capsules remained continuously proliferation and lined up in continuous layers. In addition, the urothelial cells on the capsular stents with an embedding period of 2 or 3 weeks showed higher proliferative viability compared with the cells on the stents with an embedding time of 1 week (P < 0.05). The results of the study indicated that the prefabricated capsular stents could serve as alternative cell carriers for tissue engineered ureters, especially with embedding time from 2 to 3 weeks.
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Affiliation(s)
- Yongde Xu
- Department of Urology, PLA General Hospital, Military Postgraduate Medical College, Haidian District, Beijing, China
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95
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Fu WJ, Xu YD, Wang ZX, Li G, Shi JG, Cui FZ, Zhang Y, Zhang X. New ureteral scaffold constructed with composite poly(L-lactic acid)-collagen and urothelial cells by new centrifugal seeding system. J Biomed Mater Res A 2012; 100:1725-33. [PMID: 22447771 DOI: 10.1002/jbm.a.34134] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2012] [Revised: 02/19/2012] [Accepted: 02/21/2012] [Indexed: 11/07/2022]
Abstract
A tissue-engineered ureteral scaffold was constructed with composited poly L-lactic acid (PLLA)-collagen endoluminal stent and uroepithelial cells (UECs) using a new seeding system. The electrospun PLLA-collagen nanofibrous mesh was seeded efficiently with human ureteral epithelial cells using a modified centrifugal seeding device. The cellular nanofibrous mesh was then wound around a spiral endoluminal stent to form a cellular composited PLLA-collagen ureteral scaffold. The cellular ureteral scaffold was subcutaneously implanted into nude mice. Cell attachment, distribution, and viability in vitro were investigated along with the cell fate in vivo. (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay showed that scaffolds seeded with centrifugal method had higher cellular activity than scaffolds seeded with static method (p < 0.05), and the metabolic activity per cell had no significant differences between the two methods (p > 0.05). Histologic analysis showed that the entrapped UECs remained in the scaffolds after 2 wk of implantation. The results of the study indicated that the composited PLLA-collagen endoluminal stent could serve as alternative cell carrier for tissue engineering ureter. In addition, the new modified centrifugal seeding system allowed rapid homogeneous distribution of cells onto the nanofibrous mesh, which will be useful to ureteral reconstruction.
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Affiliation(s)
- Wei-Jun Fu
- Department of Urology, Chinese People's Liberation Army General Hospital, Military Postgraduate Medical College, Haidian District, Beijing 100853, People's Republic of China.
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Cheng HLM, Loai Y, Farhat WA. Monitoring tissue development in acellular matrix-based regeneration for bladder tissue engineering: multiexponential diffusion and T2* for improved specificity. NMR IN BIOMEDICINE 2012; 25:418-426. [PMID: 22351641 DOI: 10.1002/nbm.1617] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2010] [Revised: 06/26/2010] [Accepted: 08/10/2010] [Indexed: 05/31/2023]
Abstract
Cell-seeded acellular matrices (ACMs) are a promising approach for the tissue engineering of soft tissues and organs, such as the urinary bladder. ACM contains site-preferred structural and functional molecules, and degradation products derived from ACM play important roles in tissue remodeling. Regeneration proceeds along concurrent trajectories of cell growth and matrix degradation, characterized by evolving biophysical and biochemical properties. The assessment of tissue development through a noninvasive imaging technique, such as MRI, must therefore be capable of distinguishing these concurrent biophysical and biochemical changes. However, although MRI provides exquisite sensitivity to tissue microstructure, composition and function, specificity remains limited. In this study, multiexponential diffusion and the effective transverse relaxation time T(2)* were investigated for their ability to assess cell growth and tissue composition, respectively. Bladder ACMs prepared with and without hyaluronic acid, and ACMs seeded with smooth muscle cells, were assessed on MRI. The slow diffusion fraction from multiexponential diffusion analysis demonstrated the best correlation with cellularity, with minimal influence from underlying matrix degradation. T(2)* measurements were sensitive to macromolecular content, specifically the presence of hyaluronic acid, without confounding influence from tissue hydration. T(2)* also appeared to be sensitive to cell filling of the matrix pore space. Compared with these metrics, commonly used MRI parameters, such as T(1), T(2) and single diffusion coefficients, were more limited in specificity. The use of T(2) to measure tissue structure and composition is limited by its large dependence on water content, and single diffusion can only reflect the overall characteristics of the extra- and intracellular environment. These findings are important for further development of more specific MRI methods for the monitoring of regeneration in tissue-engineered systems.
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Patel MN, Atala A. Tissue engineering of the penis. ScientificWorldJournal 2011; 11:2567-78. [PMID: 22235188 PMCID: PMC3253692 DOI: 10.1100/2011/323989] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2010] [Accepted: 08/27/2010] [Indexed: 12/20/2022] Open
Abstract
Congenital disorders, cancer, trauma, or other conditions of the genitourinary tract can lead to significant organ damage or loss of function, necessitating eventual reconstruction or replacement of the damaged structures. However, current reconstructive techniques are limited by issues of tissue availability and compatibility. Physicians and scientists have begun to explore tissue engineering and regenerative medicine strategies for repair and reconstruction of the genitourinary tract. Tissue engineering allows the development of biological substitutes which could potentially restore normal function. Tissue engineering efforts designed to treat or replace most organs are currently being undertaken. Most of these efforts have occurred within the past decade. However, before these engineering techniques can be applied to humans, further studies are needed to ensure the safety and efficacy of these new materials. Recent progress suggests that engineered urologic tissues and cell therapy may soon have clinical applicability.
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Affiliation(s)
- Manish N Patel
- Wake Forest Institute for Regenerative Medicine, Medical Center Boulevard, Winston-Salem, NC 27157, USA
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Feng C, Xu YM, Fu Q, Zhu WD, Cui L. Reconstruction of Three-Dimensional Neourethra Using Lingual Keratinocytes and Corporal Smooth Muscle Cells Seeded Acellular Corporal Spongiosum. Tissue Eng Part A 2011; 17:3011-9. [PMID: 21736450 DOI: 10.1089/ten.tea.2011.0061] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Chao Feng
- Department of Urology, Affiliated Sixth People's Hospital, Shanghai Jiaotong University, Shanghai, People's Republic of China
| | - Yue-min Xu
- Department of Urology, Affiliated Sixth People's Hospital, Shanghai Jiaotong University, Shanghai, People's Republic of China
| | - Qiang Fu
- Department of Urology, Affiliated Sixth People's Hospital, Shanghai Jiaotong University, Shanghai, People's Republic of China
| | - Wei-dong Zhu
- Department of Urology, Affiliated Sixth People's Hospital, Shanghai Jiaotong University, Shanghai, People's Republic of China
| | - Lei Cui
- Shanghai Tissue Engineering Research and Development Center, Shanghai, People's Republic of China
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Fu Q, Cao YL. Tissue engineering and stem cell application of urethroplasty: from bench to bedside. Urology 2011; 79:246-53. [PMID: 22014966 DOI: 10.1016/j.urology.2011.08.043] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2011] [Revised: 08/13/2011] [Accepted: 08/18/2011] [Indexed: 01/15/2023]
Abstract
OBJECTIVE To review the advances in the basic research and clinical application of tissue engineering and stem cell technology in urethral reconstruction. Urethral defects resulting from congenital malformations, trauma, inflammation, or cancer are a common urologic issue. Traditional urethral reconstruction is associated with various complications. Tissue engineering and stem cell technology hold novel therapeutic promise for urethral reconstruction. METHODS One of us searched the PubMed database (January 1999 to January 2011) using the English search terms "tissue engineering," "stem cells," "urethral reconstruction," and "urethra." A total of 86 reports were retrieved. After the repetitive and irrelevant reports were excluded, 40 were included in the final analysis. The review outlined and evaluated the advances in basic research and clinical application and the current status and prospects of tissue engineering and stem cell technology in urinary reconstruction. RESULTS Two therapeutic strategies are available for urethral reconstruction using tissue engineering: the acellular matrix bioscaffold model and the cell-seeded bioscaffold model. The acellular matrix bioscaffold model has been successfully used in the clinic and the cell-seeded bioscaffold model is making its transition from bench to bedside. CONCLUSION Stem cells can provide the seed cells for urologic tissue engineering, but much basic research is still needed before their clinical use is possible.
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Affiliation(s)
- Qiang Fu
- Department of Urology, Shanghai 6th People's Hospital, Shanghai Jiaotong University, Shanghai, China.
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Abstract
The term 'regenerative medicine' encompasses strategies for restoring or renewing tissue or organ function by: (i) in vivo tissue repair by in-growth of host cells into an acellular natural or synthetic biomaterial, (ii) implantation of tissue 'engineered'in vitro by seeding cultured cells into a biomaterial scaffold, and (iii) therapeutic cloning and stem cell-based tissue regeneration. In this article, we review recent developments underpinning the emerging science of regenerative medicine and critically assess where successful implementation of novel regenerative medicine approaches into urology practice might genuinely transform the quality of life of affected individuals. We advocate the need for an evidence-based approach supported by strong science and clinical objectivity.
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Affiliation(s)
- Felix Wezel
- Jack Birch Unit for Molecular Carcinogenesis, Department of Biology, University of York, York, UK
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