James J Yoo

Kyungpook National University, Daikyū, Daegu, South Korea

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Publications (134)768.59 Total impact

  • Julie Marco · Anthony Atala · James J. Yoo
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    ABSTRACT: Full-thickness skin wounds and extensive burn injuries are a major cause of morbidity and mortality. Currently, the clinical standard for wound treatment is the use of autologous split-thickness skin grafts, which is associated with donor site morbidity. Use of allografts often leads to an immune response and rejection. Other skin substitutes, synthetic and biologic, have been used, but each has advantages and disadvantages. Recently, direct application of skin cells onto wound sites has become a method to accelerate wound healing. To efficiently deliver cells onto the wound site for uniform coverage, bioprinting technology has been proposed as a delivery method. This chapter discusses the printer design and parameters specific to skin bioprinting applications for wound healing and skin repair.
    No preview · Article · Dec 2015
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    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.
    No preview · Article · Dec 2015 · Journal of Tissue Engineering and Regenerative Medicine
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    ABSTRACT: The long term efficacy of tissue based heart valve grafts may be limited by progressive degeneration characterized by immune mediated inflammation and calcification. To avoid this degeneration, decellularized heart valves with functionalized surfaces capable of rapid in vivo endothelialization have been developed. The aim of this study is to examine the capacity of CD133 antibody-conjugated valve tissue to capture circulating endothelial progenitor cells (EPCs). Decellularized human pulmonary valve tissue was conjugated with CD133 antibody at varying concentrations and exposed to CD133 expressing NTERA-2 cl.D1 (NT2) cells in a microflow chamber. The amount of CD133 antibody conjugated on the valve tissue surface and the number of NT2 cells captured in the presence of shear stress was measured. Both the amount of CD133 antibody conjugated to the valve leaflet surface and the number of adherent NT2 cells increased as the concentration of CD133 antibody present in the surface immobilization procedure increased. The data presented in this study support the hypothesis that the rate of CD133(+) cell adhesion in the presence of shear stress to decellularized heart valve tissue functionalized by CD133 antibody conjugation increases as the quantity of CD133 antibody conjugated to the tissue surface increases.
    No preview · Article · Sep 2015 · Biomedical Materials
  • So Young Chun · Se Heang Oh · James J Yoo · Tae Gyun Kwon
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    ABSTRACT: Organ transplantation has often been successful for treatment of end-stage organ failure. However, the shortage of donor organ still remains problematic in clinical practices. As an alternative, the tissue-engineering approach for functional organ replacement has been extensively studied. More recently, decellularized organs have been emerged as a promising scaffold for reconstruction of the complicated organs (e.g., heart, liver, lung and kidney). The ideal decellularized organ scaffolds need to contain extracellular matrix (ECM), bioactive molecules, vascular systems and tissue microarchitecture. To fulfill these requirements, physical, chemical, and biological techniques have been adapted in the process of organ decellularization. In this review, the representative techniques for the organ decellularization and their characterization as well as considerations for implantation are discussed.
    No preview · Article · Feb 2015 · Tissue Engineering and Regenerative Medicine
  • Y.-J. Seol · James J. Yoo · Anthony Atala
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    ABSTRACT: Three-dimensional (3D) bioprinting technology has been utilized as a method to engineer complex tissues and organs. This rapidly growing technology allows for precise placement of multiple types of cells, biomaterials, and biomolecules in spatially predefined locations within 3D structures. Many researchers are focusing on the further development of bioprinting technology and its applications. In this chapter, we introduce the general principles and limitations of widely used bioprinting systems and applications for tissue and organ regeneration. In addition, the current challenges facing the clinical applications of bioprinting technology are addressed.
    No preview · Article · Jan 2015
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    ABSTRACT: Objective To investigate whether a triple combination of early-differentiated cells derived from human amniotic fluid stem cells (hAFSCs) would show synergistic effects in urethral sphincter regeneration. Materials and Methods We early-differentiated hAFSCs into muscle, neuron and endothelial progenitor cells and then injected them into the urethral sphincter region of pudendal neurectomized ICR mice, as single-cell, double-cell or triple-cell combinations. Urodynamic studies and histological, immunohistochemical and molecular analyses were performed. ResultsUrodynamic study showed significantly improved leak point pressure in the triple-cell-combination group compared with the single-cell- or double-cell-combination groups. These functional results were confirmed by histological and immunohistochemical analyses, as evidenced by the formation of new striated muscle fibres and neuromuscular junctions at the cell injection site. Molecular analysis showed higher target marker expression in the retrieved urethral tissue of the triple-cell-combination group. The injection of early-differentiated hAFSCs suppressed in vivo host CD8 lymphocyte aggregations and did not form teratoma. The nanoparticle-labelled early-differentiated hAFSCs could be tracked in vivo with optical imaging for up to 14 days after injection. Conclusion Our novel concept of triple-combined early-differentiated cell therapy for the damaged sphincter may provide a viable option for incontinence treatment.
    No preview · Article · May 2014 · BJU International
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    ABSTRACT: Implantation of bone substitute materials and autologous bone grafting have been used for the treatment of extensive bone defects. Recent advances in tissue engineering have led to integration of viable, biological bone grafts composed of osteogenic cells proliferating within three-dimensional (3D) scaffolds. Not only could these novel grafts be used for implantation, but also they could serve in basic and translational studies of bone development, disease, and drug discovery. The ability to isolate human cells, expand them to a large density, and differentiate them into bone-forming cells remains critical to the success of human bone graft engineering. This chapter will focus on the characteristics and limitations of human amniotic stem cells and their application in bone tissue engineering. Stem cells have proved to be an ideal source of cells for bone tissue engineering due to their ability to differentiate into osteogenic lineages. Recently, amniotic fluid-derived stem (AFS) cells that are isolated from amniotic fluid removed by amniocentesis have been identified as a novel stem cell source. The proliferative potential of these cells, along with their anti-immunogenic and non-tumorigenic properties, make them an ideal therapeutic candidate for bone tissue regeneration without ethical issues. In this chapter, the current knowledge of AFS cell isolation, characterization, and osteogenic differentiation, as well as tissue engineering approaches for the use of these cells in bone regeneration, is discussed.
    No preview · Article · Apr 2014
  • Hyun-Jung Cho · Seung Hee Lee · James J. Yoo · Yun-Hee Shon
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    ABSTRACT: A previous study demonstrated that disaccharides, antioxidants, and caspase inhibitors can be used in freezing solutions to reduce the concentration of Me2SO from the current standard of 10% (v/v) to 5% (v/v) or 2.5% and to eliminate fetal bovine serum (FBS) for the cryopreservation of human amniotic fluid-derived stem cells (AFSCs). Hence, this study investigated whether an irreversible inhibitor of caspase enzymes, benzyloxycarbonyl-Val-Ala-DL-Asp-fluoromethylketone (zVAD-fmk), could be used in post-thaw culture media to increase the survival rate of AFSCs. Our results showed that AFSCs cryopreserved in freezing solution containing trehalose, catalase, and 5% (v/v) Me2SO and then supplemented with zVAD-fmk in the post-thaw culture media showed similar post-thawing viability, proliferation, and apoptosis than cells cryopreserved in the control solution (10% (v/v) Me2SO and 20% FBS). The caspase-3 activity in all the cryopreservation solutions tested was similar to that of the control. Caspase-3, caspase-8, caspase-9, and PARP expression was not found in the cryopreserved cells. In addition, no difference was found in the survival rate and apoptosis between short-term (3 weeks) and long-term (1 year) storage of AFSCs cryopreserved in the solutions used in this study. The results of the present study demonstrate that recovery of cryopreserved cells was enhanced by using a caspase inhibitor in the post-thaw culture media.
    No preview · Article · Apr 2014 · Cryobiology
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    ABSTRACT: Human amniotic fluid stem (hAFS) cells have been shown to differentiate into multiple lineages, including myoblasts. However, molecular mechanisms underlying the myogenic differentiation of hAFS cells and their regenerative potential for muscle injury remain to be elucidated. In order to induce myogenic differentiation of hAFS cells, lentiviruses for MYOD were constructed and transduced into hAFS cells. Formation of myotube-like cells was analyzed by immunocytochemistry, and expression of molecular markers for myoblasts was analyzed by reverse transcription polymerase chain reaction and Western blotting. For in vivo muscle regeneration, MYOD transduced human AFS cells were injected into left tibialis anterior (TA) muscles injured with cardiotoxin, and muscle regeneration was analyzed using hematoxilin and eosin, immunocytochemistry, and formation of neuro-muscular junction. MYOD expression in hAFS cells successfully induced differentiation into multinucleated myotube-like cells. Consistently, significant expression of myogenic marker genes, such as MYOG, DES, DMD, and MYH, was induced by MYOD. Analysis of pre-myogenic factors showed that expression of PAX3, MEOX1, and EYA2 was significantly increased by MYOD. MYOD was phosphorylated and localized in the nucleus. These results suggest that in hAFS cells, MYOD is phosphorylated and localized in the nucleus, thus inducing expression of myogenic factors, resulting in myogenic differentiation of hAFS cells. To test regenerative potential of MYOD-transduced hAFS cells, we transplanted them into injured muscles of immunodeficient BALB/cSlc-nu mice. The results showed a substantial increase in the volume of TA muscle injected with MYOD-hAFS cells. In addition, TA muscle tissue injected with MYOD-hAFS cells has more neuro-muscular junction, indicating functional restoration of muscle injury by hAFS cells expressing by MYOD. Collectively, our data suggest that transduction of hAFS cells with MYOD lentiviruses induces skeletal myogenic differentiation in vitro and morphological and functional regeneration of injured muscle in vivo.
    Preview · Article · Dec 2013 · Stem Cell Research & Therapy
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    ABSTRACT: Cellular therapy induced transient urodynamic improvement in a rat model of Parkinson's disease where bladder dysfunction was demonstrated after unilateral injection of 6-hydroxydopamine (6-OHDA) into the medial forebrain bundle (MFB). We attempted to prolong the effect by injecting allogeneic rat bone marrow mesenchymal stromal cells before (rBMSC) and after microencapsulation (ErBMSC) into the substantia nigra pars compacta (SNpc). Female rats underwent a unilateral stereotactic injection of 6-OHDA in the MFB. Treatment injection was performed in the ipsilateral SNpc of vehicle alone, or with either rBMSC or ErBMSC. Animals were evaluated by cystometry at four different time points after treatment: 7, 14, 28, and 42 days. Brains were extracted for immunostaining. At 42 days, the rBMSC group had lower threshold pressure (TP), intermicturition pressure, spontaneous activity (SA) and area under the curve than vehicle treated animals. The ErBMSC animals had lower TP at 28 days and lower SA at 42 days compared to vehicle treated animals. ErBMSC and rBMSC were demonstrated in the SNpc up to 42 days following transplantation. At 42 days, tyrosine hydroxylase (TH) positive neurons were more numerous in the SNpc of rBMSC, followed by ErBMSC, and vehicle treated animals. Urodynamic effects of the 6-OHDA lesion persisted up to 42 days after vehicle injection. Transplantation of rBMSC improved urodynamic pressures at 42 days after treatment more markedly than ErBMSC. This was associated with a higher number of TH-positive neurons in the treated SNpc of rBMSC animals, suggesting that functional improvements require a juxtacrine effect.
    Full-text · Article · Aug 2013 · The Journal of urology
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    ABSTRACT: Mesencymal stem cells have been used as an "off the shelf" cellular therapeutics due to their immunomodulatory properties. However, cryoprotectants used to store these cells have not been adequately studied, in terms of their safety and efficacy. In this study, we investigated whether use of natural cryoprotectants free of animal products would be effective in the cryopreservation of human bone marrow-derived mesenchymal stem cells (BMSCs). Cryopreservation medium containing disaccharides, antioxidants and caspase inhibitors combined with a reduced concentration of dimethylsulfoxide (DMSO) was used to cryopreserve BMSCs. The cells were tested for viability with cck-8 assay and a growth curve was generated to measure population doubling. In addition, flow cytometry analysis for cell surface antigens, and RT-PCR for mRNA expression of stem cell markers were performed. The solutions containing trehalose and catalase with 5% or 2.5% (v/v) DMSO produced results similar to those for that of the control (10% (v/v) DMSO and 30% FBS), in terms of cell viability, culture growth, expression of cell surface antigens and mRNA expression of stem cell markers in BMSCs cryopreserved for 3 weeks. Thus, these results show that BMSCs can be cryopreserved with a reduced concentration of DMSO with the addition of disaccharides, antioxidants and caspase inhibitors. This study suggests that human BMSCs can be effectively cryopreserved using natural cryoprotectants combined with reduced concentration of DMSO for cell therapy applications.
    No preview · Article · Aug 2013 · Tissue Engineering and Regenerative Medicine
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    ABSTRACT: Timely innervation of muscle tissue is critical in the recovery of function, and this time-sensitive process relies heavily on the host tissue microenvironment after implantation. However, restoration of muscle tissue mass and function has been a challenge. We investigated whether pre-forming acetylcholine receptor (AChR) clusters on engineered muscle fibers using an AChR cluster-inducing factor (agrin) prior to implantation would facilitate established contacts between implanted muscle tissues and nerves and result in rapid innervation of engineered muscle in vivo. We showed that agrin treatment significantly increased the formation of AChR clusters on culture differentiated myotubes (C2C12), enhanced contacts with nerves in vitro and in vivo, and increased angiogenesis. Pre-fabrication of AChR clusters on engineered skeletal muscle using a released neurotrophic factor can accelerate innervations following implantation in vivo. This technique has considerable potential for enhancing muscle tissue function.
    No preview · Article · Feb 2013 · Biomaterials
  • Weijie Xu · Anthony Atala · James J Yoo · Sang Jin Lee
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    ABSTRACT: Tissue engineered scaffolds should actively participate not only in structural support but also in functional tissue regeneration. Thus, novel smart biomaterial scaffolds have been developed, which incorporate a variety of bioactive molecules to accelerate neo-tissue formation. The effective delivery of multiple bioactive molecules with distinct kinetics to target sites at an appropriate concentration and in a timely manner is desired to drive tissue development to completion. To achieve effective, controllable delivery of multiple factors, a dual protein delivery system has been developed by electrospinning poly(lactide-co-glycolide) (PLGA) with different hydrophilicities. Bovine serum albumin or myoglobin was incorporated into and released gradually from these electrospun fibrous PLGA scaffolds. All the scaffolds exhibited similar loading efficiencies of approximately 80% of the target proteins. The introduction of Pluronic F-127 (PF127) dramatically increased scaffold hydrophilicity, which affected the release kinetics of these proteins from the scaffolds. Furthermore, distinct protein release patterns were achieved when using dual protein-loaded scaffolds with different hydrophilicities when these scaffolds were fabricated by co-electrospinning. This system may be useful as a method for delivering multiple bioactive vehicles for tissue engineering applications.
    No preview · Article · Feb 2013 · Biomedical Materials
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    ABSTRACT: Stem cells have become an important component of tissue regeneration, as they are able to differentiate into various cell types if guided appropriately. It is well known that cellular differentiation is greatly influenced by the surrounding microenvironment. We have developed a composite scaffold system using a collagen matrix derived from porcine bladder submucosa matrix (BSM) and poly(lactide-co-glycolide) (PLGA). In this study, we investigated whether a composite scaffold composed of naturally derived matrix combined with synthetic polymers would provide a microenvironment to facilitate the induction of osteogenic differentiation. We first showed that human amniotic fluid-derived stem cells (hAFSCs) adhered to the composite scaffolds and proliferated over time. We also showed that the composite scaffolds facilitated the differentiation of hAFSCs into an osteogenic lineage. The expression of osteogenic genes, including RUNX2, osteopontin (OPN) and osteocalcin (OCN) was upregulated in cells cultured on the composite scaffolds incubated in the osteogenic medium compared with ones without. Increased alkaline phosphatase (ALP) activity and calcium content indicates that hAFSCs seeded on 3D porous BSM-PLGA composite scaffolds resulted in higher mineralization rates as the duration of induction increased. This was also evidenced by the mineralized matrix within the scaffolds. The composite scaffold system provides a proper microenvironment that can facilitate osteogenic differentiation of AFSCs. This scaffold system may be a good candidate material for bone tissue engineering.
    Full-text · Article · Feb 2013 · Biomedical Materials
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    ABSTRACT: Tissue-engineered muscle has been proposed as a means of repairing volumetric muscle defects to restore anatomical and functional recovery. We have previously demonstrated that denervated muscle, which is analogous to engineered muscle construct, can be reinnervated by direct transplantation of host nerve (neurotization) in a rat model. However, the use of this approach is not possible if the length of host nerve is inadequate and cannot be mobilized to the insertion site of the engineered muscle. In this study we investigated whether neurotization coupled with nerve guidance channels would increase the regeneration of neuromuscular junctions (NMJs) in completely denervated muscle and encourage neurofunctional recovery. Seventy-two Lewis rats were evaluated in three groups, a normal control group (n = 8), a denervated group (n = 32) and a neurotization coupled with nerve guidance group (n = 32). Neurofunctional behaviour and histological evaluations were performed at 4, 8, 12 and 20 weeks postoperatively. Extensor postural thrust (EPT) and compound muscle action potential (CMAP) amplitude were significantly improved in the nerve guidance group when compared with the denervated group, even though these values were different from those of the normal control group at 20 weeks postoperation. Regeneration of axons and NMJs was demonstrated histologically in the nerve guidance group. Neurotization coupled with nerve guidance channels leads to regeneration of axons and NMJs in completely denervated muscle. To our knowledge, this is the first report to show that nerve guidance can allow re-innervation in denervated muscle containing long-gap nerve injuries. Copyright © 2013 John Wiley & Sons, Ltd.
    Full-text · Article · Jan 2013 · Journal of Tissue Engineering and Regenerative Medicine
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    ABSTRACT: Although hormone replacement therapy is an option for the loss of ovarian function, hormone delivery through pharmacological means results in various clinical complications. The present study was designed to deliver sex steroids by a functional construct fabricated using encapsulation techniques. Theca and granulosa cells isolated from ovaries of 21-day old rats were encapsulated in multilayer alginate microcapsules to recapitulate the native follicular structure. Cells encapsulated in two other schemes were used as controls to assess the importance of the multilayer structure. The endocrine functions of the encapsulated cells were assessed in vitro for a period of 30 days. Encapsulated cells showed sustained viability during long-term in vitro culture with those encapsulated in multilayer capsules secreting significantly higher and sustained concentrations of 17 β-estradiol (E(2)) than the two other encapsulation schemes (p < 0.05, n = 6) in response to follicle-stimulating hormone (FSH) and luteinizing hormone (LH). In addition, cells in the multilayer microcapsules also secreted activin and inhibin in vitro. In contrast, when granulosa and theca cells were cultured in 2D culture, progesterone (P(4)) secretion increased while E(2) secretion decreased over a 30-day period. In summary, we have designed a multilayer engineered ovarian tissue that secretes sex steroids and peptide hormones and responds to gonadotropins, thus demonstrating the ability to recapitulate native ovarian structure ex vivo.
    Full-text · Article · Dec 2012 · Biomaterials
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    ABSTRACT: Oxygen and nutrients cannot be delivered to cells residing in the interior of large-volume scaffolds via diffusion alone. Several efforts have been made to meet the metabolic needs of cells in a scaffold by constructing mass transport channels, particularly in the form of bifurcating networks. In contrast with progress in fabrication technologies, however, an approach to designing an optimal network based on experimental evaluation has not been actively reported. The main objective of this study was to establish a procedure for designing an effective microfluidic network system for a cell-seeded scaffold and to develop an experimental model to evaluate the design. We proposed a process to design a microfluidic network by combining an oxygen transport simulation with biomimetic principles governing biological vascular trees. The simulation was performed with the effective diffusion coefficient (De,s ), which was experimentally measured in our previous study. Porous scaffolds containing an embedded microfluidic network were fabricated using the lost mold shape-forming process and salt leaching method. The reliability of the procedure was demonstrated by experiments using the scaffolds. This approach established a practical basis for designing an effective microfluidic network in a cell-seeded scaffold.
    No preview · Article · Dec 2012 · Langmuir
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    ABSTRACT: Bioprinting is an emerging technique used to fabricate viable, 3D tissue constructs through the precise deposition of cells and hydrogels in a layer-by-layer fashion. Despite the ability to mimic the native properties of tissue, printed 3D constructs that are composed of naturally-derived biomaterials still lack structural integrity and adequate mechanical properties for use in vivo, thus limiting their development for use in load-bearing tissue engineering applications, such as cartilage. Fabrication of viable constructs using a novel multi-head deposition system provides the ability to combine synthetic polymers, which have higher mechanical strength than natural materials, with the favorable environment for cell growth provided by traditional naturally-derived hydrogels. However, the complexity and high cost associated with constructing the required robotic system hamper the widespread application of this approach. Moreover, the scaffolds fabricated by these robotic systems often lack flexibility, which further restrict their applications. To address these limitations, advanced fabrication techniques are necessary to generate complex constructs with controlled architectures and adequate mechanical properties. In this study, we describe the construction of a hybrid inkjet printing/electrospinning system that can be used to fabricate viable tissues for cartilage tissue engineering applications. Electrospinning of polycaprolactone fibers was alternated with inkjet printing of rabbit elastic chondrocytes suspended in a fibrin-collagen hydrogel in order to fabricate a five-layer tissue construct of 1 mm thickness. The chondrocytes survived within the printed hybrid construct with more than 80% viability one week after printing. In addition, the cells proliferated and maintained their basic biological properties within the printed layered constructs. Furthermore, the fabricated constructs formed cartilage-like tissues both in vitro and in vivo as evidenced by the deposition of type II collagen and glycosaminoglycans. Moreover, the printed hybrid scaffolds demonstrated enhanced mechanical properties compared to printed alginate or fibrin-collagen gels alone. This study demonstrates the feasibility of constructing a hybrid inkjet printing system using off-the-shelf components to produce cartilage constructs with improved biological and mechanical properties.
    Full-text · Article · Nov 2012 · Biofabrication
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    ABSTRACT: The most promising treatment for stress urinary incontinence can be a cell therapy. We suggest human amniotic fluid stem cells (hAFSCs) as an alternative cell source. We established the optimum in vitro protocol for the differentiation from hAFSCs into muscle progenitors. These progenitors were transplanted into the injured urethral sphincter and their therapeutic effect was analyzed. For the development of an efficient differentiation system in vitro, we examined a commercial medium, co-culture and conditioned medium (CM) systems. After being treated with CM, hAFSCs were effectively developed into a muscle lineage. The progenitors were integrated into the host urethral sphincter and the host cell differentiation was stimulated in vivo. Urodynamic analysis showed significant increase of leak point pressure and closing pressure. Immunohistochemistry revealed the regeneration of circular muscle mass with normal appearance. Molecular analysis observed the expression of a larger number of target markers. In the immunogenicity analysis, the progenitor group had a scant CD8 lymphocyte. In tumorigenicity, the progenitors showed no teratoma formation. These results suggest that hAFSCs can effectively be differentiated into muscle progenitors in CM and that the hAFSC-derived muscle progenitors are an accessible cell source for the regeneration of injured urethral sphincter.
    Preview · Article · Nov 2012 · Journal of Korean medical science
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    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. Copyright © 2012 John Wiley & Sons, Ltd.
    No preview · Article · Nov 2012 · Journal of Tissue Engineering and Regenerative Medicine

Publication Stats

8k Citations
768.59 Total Impact Points

Institutions

  • 2012-2014
    • Kyungpook National University
      • Department of Urology
      Daikyū, Daegu, South Korea
  • 2005-2014
    • Wake Forest University
      • School of Medicine
      Winston-Salem, North Carolina, United States
  • 2005-2013
    • Wake Forest School of Medicine
      • • Department of Urology
      • • Institute for Regenerative Medicine
      Winston-Salem, North Carolina, United States
  • 2010
    • Kyungpook National University Hospital
      Sŏul, Seoul, South Korea
  • 1997-2004
    • Harvard Medical School
      • Department of Surgery
      Boston, Massachusetts, United States
  • 2003
    • Ain Shams University
      Al Qāhirah, Muḩāfaz̧at al Qāhirah, Egypt
  • 1999
    • Boston University
      • Department of Urology
      Boston, Massachusetts, United States
  • 1997-1998
    • Boston Children's Hospital
      • Department of Urology
      Boston, Massachusetts, United States