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Zhao P, Fang Q, Gao D, Wang Q, Cheng Y, Ao Q, Wang X, Tian X, Zhang Y, Tong H, Yan N, Hu X, Fan J. Klotho functionalization on vascular graft for improved patency and endothelialization. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2022; 133:112630. [DOI: 10.1016/j.msec.2021.112630] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 12/13/2021] [Accepted: 12/19/2021] [Indexed: 10/19/2022]
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Shan Z, Lin X, Wang S, Zhang X, Pang Y, Li S, Yu T, Fan S, Zhao F. An injectable nucleus pulposus cell-modified decellularized scaffold: biocompatible material for prevention of disc degeneration. Oncotarget 2018; 8:40276-40288. [PMID: 28402966 PMCID: PMC5522320 DOI: 10.18632/oncotarget.16831] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Accepted: 02/27/2017] [Indexed: 01/22/2023] Open
Abstract
We developed a nucleus pulposus cell (NPC)-modulated decellularized small intestinal submucosa (SIS) scaffold, and assessed the ability of this material to prevent Intervertebral disc degeneration (IVD) degeneration. Decellularized porcine SIS was squashed into particles and the biological safety and efficiency of these particles were evaluated. Next, SIS particles were seeded with rabbit NPCs, cultured for two months in vitro, decellularized again and suspended for intervertebral injection. We demonstrated that use of the decellularization protocol resulted in the removal of cellular components with maximal retention of extracellular matrix. The xenogeneic decellularized SIS did not display cytotoxicity in vitro and its application prevented NPC degradation. Furthermore, the xenogeneic SIS microparticles were effective in preventing IVD progression in vivo in a rabbit disc degeneration model. In conclusion, our study describes an optimized method for decellularized SIS preparation and demonstrated that the material is safe and effective for treating IVD degeneration.
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Affiliation(s)
- Zhi Shan
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Medical College of Zhejiang University, Hangzhou, 310016, China
| | - Xianfeng Lin
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Medical College of Zhejiang University, Hangzhou, 310016, China
| | - Shengyu Wang
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Medical College of Zhejiang University, Hangzhou, 310016, China
| | - Xuyang Zhang
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Medical College of Zhejiang University, Hangzhou, 310016, China
| | - Yichuan Pang
- MOE Key Laboratory of Macromolecular synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Shengyun Li
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Medical College of Zhejiang University, Hangzhou, 310016, China
| | - Tianming Yu
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Medical College of Zhejiang University, Hangzhou, 310016, China
| | - Shunwu Fan
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Medical College of Zhejiang University, Hangzhou, 310016, China
| | - Fengdong Zhao
- Department of Orthopaedic Surgery, Sir Run Run Shaw Hospital, Medical College of Zhejiang University, Hangzhou, 310016, China
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Row S, Santandreu A, Swartz DD, Andreadis ST. Cell-free vascular grafts: Recent developments and clinical potential. TECHNOLOGY 2017; 5:13-20. [PMID: 28674697 PMCID: PMC5492388 DOI: 10.1142/s2339547817400015] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Recent advances in vascular tissue engineering have led to the development of cell-free grafts that are available off-the-shelf for on demand surgery. Challenges associated with cell-based technologies including cell sourcing, cell expansion and long-term bioreactor culture motivated the development of completely cell-free vascular grafts. These are based on decellularized arteries, decellularized cultured cell-based tissue engineered grafts or biomaterials functionalized with biological signals that promote in situ tissue regeneration. Clinical trials undertaken to demonstrate the applicability of these grafts are also discussed. This comprehensive review summarizes recent developments in vascular graft technologies, with potential applications in coronary artery bypass procedures, lower extremity bypass, vascular injury and trauma, congenital heart diseases and dialysis access shunts, to name a few.
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Affiliation(s)
- Sindhu Row
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Amherst, NY 14260-4200, USA
- Angiograft LLC, Amherst NY
| | - Ana Santandreu
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Amherst, NY 14260-4200, USA
| | | | - Stelios T Andreadis
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Amherst, NY 14260-4200, USA
- Department of Biomedical Engineering, University at Buffalo, The State University of New York, Amherst, NY 14260-4200, USA
- New York State Center of Excellence in Bioinformatics and Life Sciences, Buffalo, NY
- Angiograft LLC, Amherst NY
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Bryant D, Holtby R, Willits K, Litchfield R, Drosdowech D, Spouge A, White D, Guyatt G. A randomized clinical trial to compare the effectiveness of rotator cuff repair with or without augmentation using porcine small intestine submucosa for patients with moderate to large rotator cuff tears: a pilot study. J Shoulder Elbow Surg 2016; 25:1623-33. [PMID: 27545050 DOI: 10.1016/j.jse.2016.06.006] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Revised: 05/26/2016] [Accepted: 06/07/2016] [Indexed: 02/01/2023]
Abstract
BACKGROUND The rate of rotator cuff repair failure is between 13% and 67%. Porcine small intestine submucosa (SIS) may be suitable to augment the repair. METHODS There were 62 patients with moderate and large cuff tears randomized to repair alone (control) or augmentation with SIS (Restore Orthobiologic Implant; DePuy, Warsaw, IN, USA). Primary outcome was repair failure using magnetic resonance arthrography. Randomization occurred on completion of the repair. Patients and assessors were blind to group. Assessments occurred preoperatively and postoperatively at 2 and 6 weeks and 3, 6, 12, and 24 months. RESULTS There were 62 patients randomized (34 SIS, 28 control). Patient demographics, rotator cuff tear characteristics, and repair details were similar between groups. At 1 year, risk of failure was 52.9% (18/34) in the SIS group and 65.4% (17/26) in the control group for a risk difference of 12% (80% confidence interval, -7% to 32%) or relative risk of 0.81 (95% confidence interval, 0.53-1.24, P = .33) in favor of SIS. At 1 and 2 years, the mean difference between groups for patient-reported outcomes was small and consistent with chance but did not exclude the possibility of a clinically important difference. There was no statistically significant difference (P = .50) between the SIS group (59.6 ± 38.9; range, 3-112) and the control group (52.7 ± 38.6; range, 5-112) in number of days to being narcotic and pain free (<20 mm on a 100-mm visual analog scale). CONCLUSION We found no evidence that SIS-augmented rotator cuff repair provides superior outcomes in patients with moderate rotator cuff tears.
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Affiliation(s)
- Dianne Bryant
- Western University, London, ON, Canada; McMaster University, Hamilton, ON, Canada
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5
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Romanelli M, Gilligan AM, Waycaster CR, Dini V. Difficult-to-heal wounds of mixed arterial/venous and venous etiology: a cost-effectiveness analysis of extracellular matrix. CLINICOECONOMICS AND OUTCOMES RESEARCH 2016; 8:153-61. [PMID: 27217787 PMCID: PMC4862353 DOI: 10.2147/ceor.s104067] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Importance Difficult-to-heal wounds pose clinical and economic challenges, and cost-effective treatment options are needed. Objective The aim of this study is to determine the cost-effectiveness of extracellular matrix (ECM) relative to standard of care (SC) on wound closure for the treatment of mixed arterial/venous (A/V) or venous leg ulcers (VLUs). Design, setting, and participants A two-stage Markov model was used to predict the expected costs and outcomes of wound closure for ECM and SC. Outcome data used in the analysis were taken from an 8-week randomized clinical trial that directly compared ECM and SC. Patients were followed up for an additional 6 months to assess wound closure. Forty-eight patients completed the study; 25 for ECM and 23 for SC. SC was defined as a standard moist wound dressing. Transition probabilities for the Markov states were estimated from the clinical trial. Main outcomes and measures The economic outcome of interest was direct cost per closed-wound week. Resource utilization was based on the treatment regimen used in the clinical trial. Costs were derived from standard cost references. The payer’s perspective was taken. Results ECM-treated wounds closed, on average, after 5.4 weeks of treatment, compared with 8.3 weeks for SC wounds (P=0.02). Furthermore, complete wound closure was significantly higher in patients treated with ECM (P<0.05), with 20 wounds closed in the ECM group (80%) and 15 wounds closed in the SC group (65%). After 8 months, patients treated with ECM had substantially higher closed-wound weeks compared with SC (26.0 weeks versus 22.0 weeks, respectively). Expected direct costs per patient were $2,527 for ECM and $2,540 for SC (a cost savings of $13). Conclusion and relevance ECM yielded better clinical outcomes at a slightly lower cost in patients with mixed A/V and VLUs. ECM is an effective treatment for wound healing and should be considered for use in the management of mixed A/V and VLUs.
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Affiliation(s)
| | - Adrienne M Gilligan
- Department of Life Sciences, Truven Health Analytics, Fort Worth, TX, USA; Department of Pharmacotherapy, University of North Texas Health Sciences Center, Fort Worth, TX, USA
| | - Curtis R Waycaster
- Department of Pharmacotherapy, University of North Texas Health Sciences Center, Fort Worth, TX, USA; Department of Market Access, Smith and Nephew Inc., Fort Worth, TX, USA
| | - Valentina Dini
- Department of Dermatology, University of Pisa, Pisa, Italy
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Sánchez-Palencia D, Rathan S, Ankeny CJ, Fogg R, Briceño JC, Yoganathan AP. Mechanotransduction in small intestinal submucosa scaffolds: fabrication parameters potentially modulate the shear-induced expression of PECAM-1 and eNOS. J Tissue Eng Regen Med 2015. [PMID: 26220892 DOI: 10.1002/term.2040] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
In small intestinal submucosa (SIS) scaffolds for functional tissue engineering, the impact of scaffold fabrication parameters on cellular response and tissue regeneration may relate to the mechanotransductory properties of the final arrangement of collagen fibres. We previously proved that two fabrication parameters, (a) preservation (P) or removal (R) of a dense collagen layer present in SIS, and (b) SIS in a final dehydrated (D) or hydrated (H) state, have an effect on the micromechanical environment of SIS. In a continuation of our studies, we herein hypothesized that these fabrication parameters also modulate early mechanotransduction in cells populating the scaffold. Mechanotransduction was investigated by seeding human umbilical vein endothelial cells (HUVECs) on scaffolds, exposing them to pulsatile shear stress (12 ± 4 dyne/cm2 ) for 1 h (n = 5) in a cone-and-plate shear system, and evaluating the expression of the mechanosensitive genes Pecam1 and Enos by immunofluorescence and qPCR. Expression of mechanosensitive genes was highest in PD grafts, followed by PH and RH grafts. The RD group had similar expression to that of unsheared control cells, suggesting that the RD combination potentially reduced mechanotransduction of shear to cells. We concluded that the two fabrication parameters studied, which modify SIS micromechanics, also potentially modulated the early shear-induced expression of mechanosensitive genes in seeded HUVECs. Our findings suggest that fabrication parameters influence the outcome of SIS as a therapeutic scaffold. Copyright © 2015 John Wiley & Sons, Ltd.
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Affiliation(s)
- Diana Sánchez-Palencia
- Department of Biomedical Engineering, Universidad de los Andes, Bogota, Colombia.,CEIBA Complex Systems Research Centre, School of Engineering, Bogota, Colombia
| | - Swetha Rathan
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Casey J Ankeny
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA.,Arizona State University, School of Biological and Health Systems Engineering, Tempe, AR, USA
| | - Ruth Fogg
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Juan C Briceño
- Department of Biomedical Engineering, Universidad de los Andes, Bogota, Colombia.,CEIBA Complex Systems Research Centre, School of Engineering, Bogota, Colombia
| | - Ajit P Yoganathan
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
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Chen YC, Chen RN, Jhan HJ, Liu DZ, Ho HO, Mao Y, Kohn J, Sheu MT. Development and Characterization of Acellular Extracellular Matrix Scaffolds from Porcine Menisci for Use in Cartilage Tissue Engineering. Tissue Eng Part C Methods 2015; 21:971-86. [PMID: 25919905 DOI: 10.1089/ten.tec.2015.0036] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Given the growing number of arthritis patients and the limitations of current treatments, there is great urgency to explore cartilage substitutes by tissue engineering. In this study, we developed a novel decellularization method for menisci to prepare acellular extracellular matrix (ECM) scaffolds with minimal adverse effects on the ECM. Among all the acid treatments, formic acid treatment removed most of the cellular contents and preserved the highest ECM contents in the decellularized porcine menisci. Compared with fresh porcine menisci, the content of DNA decreased to 4.10%±0.03%, and there was no significant damage to glycosaminoglycan (GAG) or collagen. Histological staining also confirmed the presence of ECM and the absence of cellularity. In addition, a highly hydrophilic scaffold with three-dimensional interconnected porous structure was fabricated from decellularized menisci tissue. Human chondrocytes showed enhanced cell proliferation and synthesis of chondrocyte ECM including type II collagen and GAG when cultured in this acellular scaffold. Moreover, the scaffold effectively supported chondrogenesis of human bone marrow-derived mesenchymal stem cells. Finally, in vivo implantation was conducted in rats to assess the biocompatibility of the scaffolds. No significant inflammatory response was observed. The acellular ECM scaffold provided a native environment for cells with diverse physiological functions to promote cell proliferation and new tissue formation. This study reported a novel way to prepare decellularized meniscus tissue and demonstrated the potential as scaffolds to support cartilage repair.
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Affiliation(s)
- Ying-Chen Chen
- 1 School of Pharmacy, College of Pharmacy, Taipei Medical University , Taipei, Taiwan
| | - Ray-Neng Chen
- 2 Department of Cosmetics Applications and Management, Mackay Junior College of Medicine , Nursing, and Management, Taipei, Taiwan
| | - Hua-Jing Jhan
- 1 School of Pharmacy, College of Pharmacy, Taipei Medical University , Taipei, Taiwan
| | - Der-Zen Liu
- 3 Graduate Institute of Biomedical Materials and Tissue Engineering, College of Oral Medicine, Taipei Medical University , Taipei, Taiwan .,4 Center for General Education, Hsuan Chuang University , Hsinchu, Taiwan
| | - Hsiu-O Ho
- 1 School of Pharmacy, College of Pharmacy, Taipei Medical University , Taipei, Taiwan
| | - Yong Mao
- 5 New Jersey Center for Biomaterials, Rutgers, The State University of New Jersey, Piscataway, New Jersey
| | - Joachim Kohn
- 5 New Jersey Center for Biomaterials, Rutgers, The State University of New Jersey, Piscataway, New Jersey.,6 Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey , Piscataway, New Jersey
| | - Ming-Thau Sheu
- 1 School of Pharmacy, College of Pharmacy, Taipei Medical University , Taipei, Taiwan .,7 Clinical Research Center and Traditional Herbal Medicine Research Center, Taipei Medical University Hospital , Taipei, Taiwan
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8
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Row S, Peng H, Schlaich EM, Koenigsknecht C, Andreadis ST, Swartz DD. Arterial grafts exhibiting unprecedented cellular infiltration and remodeling in vivo: the role of cells in the vascular wall. Biomaterials 2015; 50:115-26. [PMID: 25736502 DOI: 10.1016/j.biomaterials.2015.01.045] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Revised: 01/13/2015] [Accepted: 01/20/2015] [Indexed: 01/21/2023]
Abstract
OBJECTIVE To engineer and implant vascular grafts in the arterial circulation of a pre-clinical animal model and assess the role of donor medial cells in graft remodeling and function. APPROACH AND RESULTS Vascular grafts were engineered using Small Intestinal Submucosa (SIS)-fibrin hybrid scaffold and implanted interpositionally into the arterial circulation of an ovine model. We sought to demonstrate implantability of SIS-Fibrin based grafts; examine the remodeling; and determine whether the presence of vascular cells in the medial wall was necessary for cellular infiltration from the host and successful remodeling of the implants. We observed no occlusions or anastomotic complications in 18 animals that received these grafts. Notably, the grafts exhibited unprecedented levels of host cell infiltration that was not limited to the anastomotic sites but occurred through the lumen as well as the extramural side, leading to uniform cell distribution. Incoming cells remodeled the extracellular matrix and matured into functional smooth muscle cells as evidenced by expression of myogenic markers and development of vascular reactivity. Interestingly, tracking the donor cells revealed that their presence was beneficial but not necessary for successful grafting. Indeed, the proliferation rate and number of donor cells decreased over time as the vascular wall was dominated by host cells leading to significant remodeling and development of contractile function. CONCLUSIONS These results demonstrate that SIS-Fibrin grafts can be successfully implanted into the arterial circulation of a clinically relevant animal model, improve our understanding of vascular graft remodeling and raise the possibility of engineering mural cell-free arterial grafts.
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Affiliation(s)
- Sindhu Row
- Department of Chemical and Biological Engineering, University at Buffalo, State University of New York, Amherst, NY 14260-4200, USA
| | - Haofan Peng
- Department of Chemical and Biological Engineering, University at Buffalo, State University of New York, Amherst, NY 14260-4200, USA
| | - Evan M Schlaich
- Department of Chemical and Biological Engineering, University at Buffalo, State University of New York, Amherst, NY 14260-4200, USA
| | - Carmon Koenigsknecht
- Department of Pediatrics, Women and Children's Hospital of Buffalo, University at Buffalo, State University of New York, Amherst, NY 14260-4200, USA
| | - Stelios T Andreadis
- Department of Chemical and Biological Engineering, University at Buffalo, State University of New York, Amherst, NY 14260-4200, USA; Department of Biomedical Engineering, University at Buffalo, State University of New York, Amherst, NY 14260-4200, USA; Center of Excellence in Bioinformatics and Life Sciences, University at Buffalo, State University of New York, Amherst, NY 14260-4200, USA.
| | - Daniel D Swartz
- Department of Pediatrics, Women and Children's Hospital of Buffalo, University at Buffalo, State University of New York, Amherst, NY 14260-4200, USA; Center of Excellence in Bioinformatics and Life Sciences, University at Buffalo, State University of New York, Amherst, NY 14260-4200, USA.
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Andrée B, Bär A, Haverich A, Hilfiker A. Small intestinal submucosa segments as matrix for tissue engineering: review. TISSUE ENGINEERING PART B-REVIEWS 2013; 19:279-91. [PMID: 23216258 DOI: 10.1089/ten.teb.2012.0583] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Tissue engineering (TE) is an emerging interdisciplinary field aiming at the restoration or improvement of impaired tissue function. A combination of cells, scaffold materials, engineering methods, and biochemical and physiological factors is employed to generate the desired tissue substitute. Scaffolds often play a pivotal role in the engineering process supporting a three-dimensional tissue formation. The ideal scaffold should mimic the native extracellular environment providing mechanical and biological properties to allow cell attachment, migration, and differentiation, as well as remodeling by the host organism. The scaffold should be nonimmunogenic and should ideally be resorbed by the host over time, leaving behind only the regenerated tissue. More than 40 years ago, a preparation of the small intestine was introduced for the replacement of vascular structures. Since then the small intestinal submucosa (SIS) has gained a lot of interest in TE and subsequent clinical applications, as this material exhibits key features of a highly supportive scaffold. This review will focus on the general properties of the SIS and its applications in therapeutical approaches as well as in generating tissue substitutes in vitro. Furthermore, the main problem of TE, which is the insufficient nourishment of cells within three-dimensional, artificial tissues exceeding certain dimensions is addressed. To solve this issue the implementation of another small intestine-derived preparation, the biological vascularized matrix (BioVaM), could be a feasible option. The BioVaM comprises in addition to SIS the arterial and venous mesenteric pedicles and exhibits thereby a perfusable vessel bed that is preserved after decellularization.
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10
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Construction of the recellularized corneal stroma using porous acellular corneal scaffold. Biomaterials 2011; 32:6962-71. [PMID: 21719100 DOI: 10.1016/j.biomaterials.2011.05.084] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2011] [Accepted: 05/27/2011] [Indexed: 12/17/2022]
Abstract
Acellular porcine cornea stroma (APCS) prepared using pancreatic phospholipase A(2) was proven to be promising corneal scaffold. However, its dense ultrastructure provides insufficient space that prevents the seeded cells from organizing into a functional tissue. In this report, freezing dry APCS (FD-APCS) biomaterials containing pores with different sizes were fabricated at different pre-freezing temperatures of -10, -80 or -198°C, and the percentage of large pores (equivalent circle diameter ≥10 μm) was 93.55%, 69.36%, 35.79%, while the small pores (<10 μm) were account for 6.45%, 30.64%, 64.21%, respectively. Both porosity and specific surface area increased in FD-APCS fabricated with decreased pre-freezing temperature, and they were dramatically higher than those in APCS. The three FD-APCS groups displayed higher permeability than APCS, and the -10°C FD-APCS possessed the highest permeability. The keratocytes seeded in the FD-APCS construct survived well in vitro, and maximal cell proliferation was observed in the -10°C FD-APCS. The light transmittance of the FD-APCS-transplanted cornea after interlamellar keratoplasty in rabbit eyes displayed no significant difference from the APCS-transplanted or native cornea. This study indicated that the porous FD-APCS prepared using pancreatic phospholipase A(2) is capable of serving as potential scaffold for constructing tissue-engineered cornea with biological properties.
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Eberli D, Atala A, Yoo JJ. One and four layer acellular bladder matrix for fascial tissue reconstruction. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2011; 22:741-751. [PMID: 21286788 DOI: 10.1007/s10856-011-4242-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2010] [Accepted: 01/14/2011] [Indexed: 05/30/2023]
Abstract
To determine whether the use of multiple layers of acellular bladder matrix (ABM) is more suitable for the treatment of abdominal wall hernia than a single layered ABM. The feasibility, biocompatibility and mechanical properties of both materials were assessed and compared. Biocompatibility testing was performed on 4 and 1 layered ABM. The matrices were used to repair an abdominal hernia model in 24 rabbits. The animals were followed for up to 3 months. Immediately after euthanasia, the implant site was inspected and samples were retrieved for histology, scanning electron microscopy and biomechanical studies. Both acellular biomaterials demonstrated excellent biocompatibility. At the time of retrieval, there was no evidence of infection. The matrices demonstrated biomechanical properties comparable to native tissue. Three hernias (25%) were found in the single layer ABM group and only 1 hernia (8%) was found in the 4 layer ABM group. Histologically, the matrix structure was intact and the cell density within the matrices decreased with time. The dominant cell type present within the matrices shifted from lymphocytes to fibroblasts over time. Both ABMs maintained adequate strength over time when used for hernia repair, and there was an extremely low incidence of adhesion formation. The single layer ABM showed enhanced cellular integration, while the 4 layer ABM reduced hernia formation. Either of these matrices may be useful as an off-the-shelf biomaterial for patients requiring fascial repair.
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Affiliation(s)
- Daniel Eberli
- Wake Forest Institute for Regenerative Medicine, Medical Center Boulevard, Winston Salem, NC 27154-1094, USA.
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12
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Valentin JE, Freytes DO, Grasman JM, Pesyna C, Freund J, Gilbert TW, Badylak SF. Oxygen diffusivity of biologic and synthetic scaffold materials for tissue engineering. J Biomed Mater Res A 2010; 91:1010-7. [PMID: 19097154 DOI: 10.1002/jbm.a.32328] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Scaffolds for tissue engineering and regenerative medicine applications are commonly manufactured from synthetic materials, intact or isolated components of extracellular matrix (ECM), or a combination of such materials. After surgical implantation, the metabolic requirements of cells that populate the scaffold depend upon adequate gas and nutrient exchange with the surrounding microenvironment. The present study measured the oxygen transfer through three biologic scaffold materials composed of ECM including small intestinal submucosa (SIS), urinary bladder submucosa (UBS), and urinary bladder matrix (UBM), and one synthetic biomaterial, Dacron. The oxygen diffusivity was calculated from Fick's first law of diffusion. Each material permitted measurable oxygen diffusion. The diffusivity of SIS was found to be dependent on the direction of oxygen transfer; the oxygen transfer in the abluminal-to-luminal direction was significantly greater than the luminal-to-abluminal direction. The oxygen diffusivity of UBM and UBS were similar despite the presence of an intact basement membrane on the luminal surface of UBM. Dacron showed oxygen diffusivity values seven times greater than the ECM biomaterials. The current study showed that each material has unique oxygen diffusivity values, and these values may be dependent on the scaffold's ultrastructure.
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Affiliation(s)
- Jolene E Valentin
- McGowan Institute for Regenerative Medicine, Pittsburgh, Pennsylvania 15219, USA
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13
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Piterina AV, Cloonan AJ, Meaney CL, Davis LM, Callanan A, Walsh MT, McGloughlin TM. ECM-based materials in cardiovascular applications: Inherent healing potential and augmentation of native regenerative processes. Int J Mol Sci 2009; 10:4375-4417. [PMID: 20057951 PMCID: PMC2790114 DOI: 10.3390/ijms10104375] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2009] [Revised: 09/07/2009] [Accepted: 09/30/2009] [Indexed: 01/21/2023] Open
Abstract
The in vivo healing process of vascular grafts involves the interaction of many contributing factors. The ability of vascular grafts to provide an environment which allows successful accomplishment of this process is extremely difficult. Poor endothelisation, inflammation, infection, occlusion, thrombosis, hyperplasia and pseudoaneurysms are common issues with synthetic grafts in vivo. Advanced materials composed of decellularised extracellular matrices (ECM) have been shown to promote the healing process via modulation of the host immune response, resistance to bacterial infections, allowing re-innervation and reestablishing homeostasis in the healing region. The physiological balance within the newly developed vascular tissue is maintained via the recreation of correct biorheology and mechanotransduction factors including host immune response, infection control, homing and the attraction of progenitor cells and infiltration by host tissue. Here, we review the progress in this tissue engineering approach, the enhancement potential of ECM materials and future prospects to reach the clinical environment.
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Affiliation(s)
- Anna V. Piterina
- Centre for Applied Biomedical Engineering Research (CABER), Department of Mechanical & Aeronautical Engineering, and Materials and Surface Science Institute (MSSI), University of Limerick, Limerick, Ireland; E-Mails:
(A.V.P.);
(A.J.C.);
(C.L.M.);
(L.M.D.);
(A.C.);
(M.T.W.)
| | - Aidan J. Cloonan
- Centre for Applied Biomedical Engineering Research (CABER), Department of Mechanical & Aeronautical Engineering, and Materials and Surface Science Institute (MSSI), University of Limerick, Limerick, Ireland; E-Mails:
(A.V.P.);
(A.J.C.);
(C.L.M.);
(L.M.D.);
(A.C.);
(M.T.W.)
| | - Claire L. Meaney
- Centre for Applied Biomedical Engineering Research (CABER), Department of Mechanical & Aeronautical Engineering, and Materials and Surface Science Institute (MSSI), University of Limerick, Limerick, Ireland; E-Mails:
(A.V.P.);
(A.J.C.);
(C.L.M.);
(L.M.D.);
(A.C.);
(M.T.W.)
| | - Laura M. Davis
- Centre for Applied Biomedical Engineering Research (CABER), Department of Mechanical & Aeronautical Engineering, and Materials and Surface Science Institute (MSSI), University of Limerick, Limerick, Ireland; E-Mails:
(A.V.P.);
(A.J.C.);
(C.L.M.);
(L.M.D.);
(A.C.);
(M.T.W.)
| | - Anthony Callanan
- Centre for Applied Biomedical Engineering Research (CABER), Department of Mechanical & Aeronautical Engineering, and Materials and Surface Science Institute (MSSI), University of Limerick, Limerick, Ireland; E-Mails:
(A.V.P.);
(A.J.C.);
(C.L.M.);
(L.M.D.);
(A.C.);
(M.T.W.)
| | - Michael T. Walsh
- Centre for Applied Biomedical Engineering Research (CABER), Department of Mechanical & Aeronautical Engineering, and Materials and Surface Science Institute (MSSI), University of Limerick, Limerick, Ireland; E-Mails:
(A.V.P.);
(A.J.C.);
(C.L.M.);
(L.M.D.);
(A.C.);
(M.T.W.)
| | - Tim M. McGloughlin
- Centre for Applied Biomedical Engineering Research (CABER), Department of Mechanical & Aeronautical Engineering, and Materials and Surface Science Institute (MSSI), University of Limerick, Limerick, Ireland; E-Mails:
(A.V.P.);
(A.J.C.);
(C.L.M.);
(L.M.D.);
(A.C.);
(M.T.W.)
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14
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Taveau JW, Tartaglia M, Buchannan D, Smith B, Koenig G, Thomfohrde K, Stouch B, Jeck S, Greene CH. Regeneration of Uterine Horn Using Porcine Small Intestinal Submucosa Grafts in Rabbits. J INVEST SURG 2009; 17:81-92. [PMID: 15204714 DOI: 10.1080/08941930490422456] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Tubal factor infertility may be reversed using porcine small-intestinal submucosa (SIS). The method uses as a model the New Zealand White rabbit uerine horn. In surgery, SIS grafts were prepared from porcine jejunum; the uterine horn segment was resected and a graft was placed; then the contralateral adnexa was resected. Fecundability was tested with natural mating. Three out of six rabbits became pregnant. Gross and microscopic examination confirmed regeneration of all tissue layers. Thus, this study determined that SIS facilitates successful regeneration of uterine horn morphology in a manner similar to that observed in other tissues and species.
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Affiliation(s)
- Jon W Taveau
- Department of Biomedical Sciences, Division of Physiology, Philadelphia College of Osteopathic Medicine, Philadelphia, Pennsylvania, USA
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15
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Pribitkin EA, Ambro BT, Bloeden E, O'Hara BJ. Rabbit Ear Cartilage Regeneration With a Small Intestinal Submucosa Graft. Laryngoscope 2009; 114:1-19. [PMID: 15475771 DOI: 10.1097/00005537-200409001-00001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES/HYPOTHESIS The objective was to demonstrate that interpositional grafting with porcine small intestinal submucosa promotes cartilage regeneration following excision of rabbit auricular cartilage. STUDY DESIGN Blinded, controlled study. METHODS Eight New Zealand white rabbits underwent excision of auricular cartilage on two sites with and two sites without preservation of perichondrium. Porcine small intestinal submucosa was implanted into one site with and one site without intact perichondrium. Remaining sites served as control sites. Histological assessment was performed at 3 (n = 4) and 6 (n = 3) months and at 1 year (n = 1) after grafting. RESULTS Histological evaluation showed cartilage regeneration accompanied by chronic inflammation in areas in which porcine small intestinal submucosa was implanted between layers of intact perichondrium. Other sites failed to show significant cartilage regeneration. CONCLUSION The results of the study using porcine small intestinal submucosa as a bioscaffold for cartilage regeneration are promising and justify further animal and human studies.
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Affiliation(s)
- Edmund A Pribitkin
- Department of Otolaryngology-Head and Neck Surgery, Jefferson Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.
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16
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Kasyanov VA, Hodde J, Hiles MC, Eisenberg C, Eisenberg L, De Castro LEF, Ozolanta I, Murovska M, Draughn RA, Prestwich GD, Markwald RR, Mironov V. Rapid biofabrication of tubular tissue constructs by centrifugal casting in a decellularized natural scaffold with laser-machined micropores. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2009; 20:329-337. [PMID: 18807150 DOI: 10.1007/s10856-008-3590-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2007] [Accepted: 09/04/2008] [Indexed: 05/26/2023]
Abstract
Centrifugal casting allows rapid biofabrication of tubular tissue constructs by suspending living cells in an in situ cross-linkable hydrogel. We hypothesize that introduction of laser-machined micropores into a decellularized natural scaffold will facilitate cell seeding by centrifugal casting and increase hydrogel retention, without compromising the biomechanical properties of the scaffold. Micropores with diameters of 50, 100, and 200 mum were machined at different linear densities in decellularized small intestine submucosa (SIS) planar sheets and tubular SIS scaffolds using an argon laser. The ultimate stress and ultimate strain values for SIS sheets with laser-machined micropores with diameter 50 mum and distance between holes as low as 714 mum were not significantly different from unmachined control SIS specimens. Centrifugal casting of GFP-labeled cells suspended in an in situ cross-linkable hyaluronan-based hydrogel resulted in scaffold recellularization with a high density of viable cells inside the laser-machined micropores. Perfusion tests demonstrated the retention of the cells encapsulated within the HA hydrogel in the microholes. Thus, an SIS scaffold with appropriately sized microholes can be loaded with hydrogel encapsulated cells by centrifugal casting to give a mechanically robust construct that retains the cell-seeded hydrogel, permitting rapid biofabrication of tubular tissue construct in a "bioreactor-free" fashion.
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17
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Xu CC, Chan RW. Pore Architecture of a Bovine Acellular Vocal Fold Scaffold. Tissue Eng Part A 2008; 14:1893-903. [DOI: 10.1089/ten.tea.2007.0243] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Affiliation(s)
- Chet C. Xu
- Department of Otolaryngology—Head and Neck Surgery, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Roger W. Chan
- Department of Otolaryngology—Head and Neck Surgery, University of Texas Southwestern Medical Center, Dallas, Texas
- Graduate Program in Biomedical Engineering, University of Texas Southwestern Medical Center, Dallas, Texas
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18
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Eberli D, Freitas Filho L, Atala A, Yoo JJ. Composite scaffolds for the engineering of hollow organs and tissues. Methods 2008; 47:109-15. [PMID: 18952175 DOI: 10.1016/j.ymeth.2008.10.014] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2008] [Revised: 10/05/2008] [Accepted: 10/16/2008] [Indexed: 11/24/2022] Open
Abstract
Several types of synthetic and naturally derived biomaterials have been used for augmenting hollow organs and tissues. However, each has desirable traits which were exclusive of the other. We fabricated a composite scaffold and tested its potential for the engineering of hollow organs in a bladder tissue model. The composite scaffolds were configured to accommodate a large number of cells on one side and were designed to serve as a barrier on the opposite side. The scaffolds were fabricated by bonding a collagen matrix to PGA polymers with threaded collagen fiber stitches. Urothelial and bladder smooth muscle cells were seeded on the composite scaffolds, and implanted in mice for up to 4 weeks and analyzed. Both cell types readily attached and proliferated on the scaffolds and formed bladder tissue-like structures in vivo. These structures consisted of a luminal urothelial layer, a collagen rich compartment and a peripheral smooth muscle layer. Biomechanical studies demonstrated that the tissues were readily elastic while maintaining their pre-configured structures. This study demonstrates that a composite scaffold can be fabricated with two completely different polymer systems for the engineering of hollow organs. The composite scaffolds are biocompatible, possess adequate physical and structural characteristics for bladder tissue engineering, and are able to form tissues in vivo. This scaffold system may be useful in patients requiring hollow organ replacement.
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Affiliation(s)
- Daniel Eberli
- Wake Forest Institute for Regenerative Medicine, Medical Center Boulevard, Winston Salem, NC 27154-1094, USA.
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19
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Korossis S, Bolland F, Ingham E, Fisher J, Kearney J, Southgate J. Review: Tissue Engineering of the Urinary Bladder: Considering Structure-Function Relationships and the Role of Mechanotransduction. ACTA ACUST UNITED AC 2006; 12:635-44. [PMID: 16674279 DOI: 10.1089/ten.2006.12.635] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
A variety of conditions encountered in urology result in bladder dysfunction and the need for bioengineered tissue substitutes. Traditionally, a number of synthetic materials and natural matrices have been used in experimental and clinical settings. However, the production of functional bladder tissue replacements remains elusive. The urinary bladder sustains considerable structural deformation during its normal function and represents an ideal model tissue in which to study the effects of biomechanical simulation on tissue morphogenesis, differentiation, and function. However, the actual role of mechanical forces within the bladder has received little attention. A strategy in which in vitro-generated tissue constructs are conditioned by exposure to the same mechanical forces as they would encounter in vivo could potentially be used both in the development of functional tissue replacements and to further study the role of biomechanical signalling. The purpose of this review is to examine the role and structure-function relationship of the urinary bladder and, through consultation of the literature available on mechanotransduction and tissue engineering of alternative tissues, to determine the factors that need to be considered when biomechanically engineering a functional bladder.
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Affiliation(s)
- Sotiris Korossis
- Biomedical Engineering Research Centre, School of Mechanical Engineering, University of Leeds, Leeds, United Kingdom
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20
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Shell DH, Croce MA, Cagiannos C, Jernigan TW, Edwards N, Fabian TC. Comparison of small-intestinal submucosa and expanded polytetrafluoroethylene as a vascular conduit in the presence of gram-positive contamination. Ann Surg 2005; 241:995-1001; discussion 1001-4. [PMID: 15912049 PMCID: PMC1357178 DOI: 10.1097/01.sla.0000165186.79097.6c] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE As a vascular conduit, expanded polytetrafluoroethylene (ePTFE) is susceptible to graft infection with Gram-positive organisms. Biomaterials, such as porcine small-intestinal submucosa (SIS), have been successfully used clinically as tissue substitutes outside the vascular arena. SUMMARY BACKGROUND DATA In the present study, we compared a small-diameter conduit of SIS to ePTFE in the presence of Gram-positive contamination to evaluate infection resistance, incorporation and remodeling, morphometry, graft patency, and neointimal hyperplasia (NH) development. METHODS Adult male mongrel pigs were randomized to receive either SIS or ePTFE (3-cm length, 6-mm diameter) and further randomized to 1 of 3 groups: Control (no graft inoculation), Staphylococcus aureus, or mucin-producing S epidermidis (each graft inoculation with 10 colonies/mL). Pressure measurements were obtained proximal and distal to the graft to create the iliac/aorta pressure ratio. Morphometric analysis of the neointima and histopathologic examinations was performed. Other outcomes included weekly WBC counts, graft incorporation, and quantitative culture of explanted grafts. RESULTS Eighteen animals were randomized. All grafts were patent throughout the 6-week study period. Infected SIS grafts had less NH and little change in their iliac/aorta indices compared with infected ePTFE grafts. Quantitative cultures at euthanasia demonstrated no growth in either SIS group compared with 1.7 x 10(4) colonies for ePTFE S aureus and 6 x 10(2) for ePTFE S epi (each P < 0.001). All SIS grafts were incorporated. Histology demonstrated remodeling into host artery with smooth muscle and capillary ingrowth in all SIS groups. Scanning electron micrography illustrated smooth and complete endothelialization of all SIS grafts. CONCLUSIONS Compared with ePTFE, SIS induces host tissue remodeling, exhibits a decreased neointimal response to infection, and is resistant to bacterial colonization. SIS may provide a superior alternative to ePTFE as a vascular conduit for peripheral vascular surgery.
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Affiliation(s)
- Daniel H Shell
- Department of Surgery, University of Tennessee Health Science Center, Memphis, Tennessee, USA
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21
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McCready RA, Hodde J, Irwin RJ, Coffey AC, Divelbiss JL, Bryant MA, Chitwood RW, Paget DS, Chess BA. Pseudoaneurysm formation in a subset of patients with small intestinal submucosa biologic patches after carotid endarterectomy. J Vasc Surg 2005; 41:782-8. [PMID: 15886661 DOI: 10.1016/j.jvs.2005.02.035] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND The carotid artery is frequently patched after carotid endarterectomy (CEA) to minimize the risks of early postoperative thrombosis and late recurrent stenosis. The small intestinal submucosa (SIS) patch is a biologic vascular patch derived from porcine small intestine. It is composed primarily of cell-free collagen and other extracellular matrix constituents that act as a scaffold for host cell deposition. METHODS In May 2001, we began an investigational trial of SIS patches in 76 patients undergoing patch angioplasty of the carotid artery after CEA. RESULTS No adverse events related to the patches were observed in the first 69 patients implanted with an SIS patch. However, in late 2002, seven patients were found to have asymptomatic pseudoaneurysms (PSA) by duplex imaging < or =10 weeks after their CEAs. The trial was immediately suspended. The PSAs were treated by surgical resection with vein grafting in two patients and placement of covered endoluminal stents in four patients. One patient is being followed as the PSA is small and has remained stable. Histopathologic examination of the SIS patch explanted from one of the surgically treated patients demonstrated the presence of actin-positive myofibroblasts or smooth muscle cells. Extensive mechanical testing of the SIS material from the two material lots associated with PSAs demonstrated thinner and more variable physical characteristics compared with control device lots. CONCLUSIONS Biologic patches that undergo active remodeling in the carotid artery require greater thickness than was anticipated to decrease wall stress and suture hole elongation. Patches exceeding this minimum thickness will be required to ensure the safety of new SIS patch designs for vascular operations.
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22
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Lu SH, Sacks MS, Chung SY, Gloeckner DC, Pruchnic R, Huard J, de Groat WC, Chancellor MB. Biaxial mechanical properties of muscle-derived cell seeded small intestinal submucosa for bladder wall reconstitution. Biomaterials 2005; 26:443-9. [PMID: 15275818 DOI: 10.1016/j.biomaterials.2004.05.006] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Bladder wall replacement remains a challenging problem for urological surgery due to leakage, infection, stone formation, and extensive time needed for tissue regeneration. To explore the feasibility of producing a more functional biomaterial for bladder reconstitution, we incorporated muscle-derived cells (MDC) into small intestinal submucosa (SIS) scaffolds. MDC were harvested from mice hindleg muscle, transfected with a plasmid encoding for beta-galactosidase, and placed into single-layer SIS cell culture inserts. Twenty-five MDC and/or SIS specimens were incubated at 37 degrees C for either 10 or 20 days. After harvesting, mechanical properties were characterized using biaxial testing, and the areal strain under 1 MPa peak stress used to quantify tissue compliance. Histological results indicated that MDC migrated throughout the SIS after 20 days. The mean (+/-SE) areal strain of the 0 day control group was 0.182 +/- 0.027 (n=5). After 10 days incubation, the mean (+/-SE) areal strain in MDC/SIS was 0.247 +/- 0.014 (n=5) compared to 10 day control SIS 0.200 +/- 0.024 (n=6). After 20 days incubation, the mean areal strain of MDC/SIS was 0.255 +/- 0.019 (n=5) compared to control SIS 0.170 +/- 0.025 (n=5). Both 10 and 20 days seeded groups were significantly different (p=0.027) than that of incubated SIS alone, but were not different from each other. These results suggest that MDC growth was supported by SIS and that initial remodeling of the SIS ECM had occurred within the first 10 days of incubation, but may have slowed once the MDC had grown to confluence within the SIS.
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Affiliation(s)
- Shing-Hwa Lu
- Department of Urology, University of Pittsburgh, Pittsburgh, PA 15219, USA
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23
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Abstract
The goal of this study is to examine whether porcine small intestine submucosa (SIS) exhibits antimicrobial properties in a standard in vitro system, without pretreatment with acetic acid or extraction of soluble proteins. Previous animal studies suggest that porcine SIS may have inherent antibiotic properties. Using the guidelines for disk diffusion susceptibility testing by Bauer, 17/64-inch diameter disks made of porcine small intestine submucosa and of gortex were compared with standard antibiotic-impregnated disks against six organisms. The zone of inhibition was measured after 24 hours and minimum bacterial concentrations were determined by serial dilutions of a solution in which porcine small intestine submucosa was allowed to elute for 24 hours. Neither porcine SIS or gortex discs caused inhibition of the growth of any organism. The porcine small intestine submucosa discs showed bacterial growth on top of the discs whereas the gortex did not. Neither the dilutional concentrations of the porcine small intestine submucosa eluent nor the gortex eluent inhibited the growth of any organism. These findings suggest that the porcine small intestine submucosa does not have intrinsic antimicrobial properties. The growth of bacteria on top of the porcine small intestine submucosa suggests that porcine small intestine submucosa itself may provide a favorable environment for the growth of bacteria. More research is necessary to decide what role porcine small intestine submucosa plays in the treatment of infected surgical sites.
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Affiliation(s)
- Paul D Holtom
- Division of Infectious Diseases, Department of Medicine, University of Southern California, Keck School of Medicine Los Angeles, CA, USA.
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24
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Abstract
Arterial occlusive disease remains the leading cause of death in western countries and often requires vascular reconstructive surgery. The limited supply of suitable small-diameter vascular grafts has led to the development of tissue engineered blood vessel substitutes. Many different approaches have been examined, including natural scaffolds containing one or more ECM proteins and degradable polymeric scaffolds. For optimal graft development, many efforts have modified the culture environment to enhance ECM synthesis and organization using bioreactors under physiologic conditions and biochemical supplements. In the past couple of decades, a great deal of progress on TEVGs has been made. Many challenges remain and are being addressed, particularly with regard to the prevention of thrombosis and the improvement of graft mechanical properties. To develop a patent TEVG that grossly resembles native tissue, required culture times in most studies exceed 8 weeks. Even with further advances in the field, TEVGs will likely not be used in emergency situations because of the time necessary to allow for cell expansion, ECM production and organization, and attainment of desired mechanical strength. Furthermore, TEVGs will probably require the use of autologous tissue to prevent an immunogenic response, unless advances in immune acceptance render allogenic and xenogenic tissue use feasible. TEVGs have not yet been subjected to clinical trials, which will determine the efficacy of such grafts in the long term. Finally, off-the-shelf availability and cost will become the biggest hurdles in the development of a feasible TEVG product. Although many obstacles exist in the effort to develop a small-diameter TEVG, the potential benefits of such an achievement are exciting. In the near future, a nonthrombogenic TEVG with sufficient mechanical strength may be developed for clinical trials. Such a graft will have the minimum characteristics of biological tissue necessary to remain patent over a period comparable to current vein graft therapies. As science and technology advance, TEVGs may evolve into complex blood vessel substitutes. TEVGs may become living grafts, capable of growing, remodeling, and responding to mechanical and biochemical stimuli in the surrounding environment. These blood vessel substitutes will closely resemble native vessels in almost every way, including structure, composition, mechanical properties, and function. They will possess vasoactive properties and be able to dilate and constrict in response to stimuli. Close mimicry of native blood vessels may aid in the engineering of other tissues dependent upon vasculature to sustain function. With further understanding of the factors involved in cardiovascular development and function combined with the foundation of knowledge already in place, the development of TEVGs should one day lead to improved quality of life for those with vascular disease and other life-threatening conditions.
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Affiliation(s)
- Rachael H Schmedlen
- Department of Bioengineering, Rice University, 6100 Main Street, MS 142 Houston, TX 77005-1892, USA
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25
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Stoll MR, Cook JL, Pope ER, Carson WL, Kreeger JM. The use of porcine small intestinal submucosa as a biomaterial for perineal herniorrhaphy in the dog. Vet Surg 2002; 31:379-90. [PMID: 12094353 DOI: 10.1053/jvet.2002.33596] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVES To develop an in vivo perineal hernia model, to develop a technique for using small intestinal submucosa (SIS) in perineal hernia repair, to further elucidate the biological behavior of SIS, and to compare SIS herniorrhaphy with the internal obturator muscle transposition (IOT) technique. STUDY DESIGN Prospective evaluation comparing SIS herniorrhaphy with IOT. ANIMALS Twelve adult castrated male, large-breed dogs. METHODS All dogs had bilateral pelvic diaphragm defects created by complete excision of the levator ani muscle. Each dog had one side repaired using SIS and the other by IOT. Pain and inflammation were subjectively scored. Dogs were killed 2 weeks (n = 4), 12 weeks (n = 4), or 16 weeks (n = 4) after surgery. Each pelvic diaphragm was biomechanically tested to failure. The pelvic diaphragms from 2 normal dogs (n = 4 sides) were also biomechanically tested. Failure site, maximum pressure, displacement at failure, and initial linear stiffness values were determined. Histologic assessment was performed. Statistical analysis was performed with significance set at P <.05 RESULTS No significant postoperative complications were noted. There were no significant differences in maximum pressure to failure, displacement, or stiffness when comparing normal, SIS, and IOT at any time point. The SIS group had significantly less displacement (P =.004) at 2 weeks than at weeks 12 or 16. For all herniorrhaphy techniques, the failure site was central (n = 22) or at the suture line (n = 2). At 2 weeks, histologic evaluation of tissues from the IOT group showed inflammation, mineralization, and necrosis, which were not present in tissues from the SIS group. Histologic examination at 12 and 16 weeks showed no microscopic differences in cell population or tissue characteristics between the IOT and SIS groups. CONCLUSIONS SIS herniorrhaphy was successfully performed in this in vivo model of perineal hernia in the dog. CLINICAL RELEVANCE This study suggests that SIS can be used as a primary means of repair, as augmentation when the internal obturator muscle is thin and friable, or as a salvage procedure in cases of recurrence in dogs with perineal hernia.
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Affiliation(s)
- Melissa R Stoll
- Department of Veterinary Medicine and Surgery, the Comparative Orthopaedic Laboratory, the College of Engineering, University of Missouri, Columbia, MO, USA
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26
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Sarikaya A, Record R, Wu CC, Tullius B, Badylak S, Ladisch M. Antimicrobial activity associated with extracellular matrices. TISSUE ENGINEERING 2002; 8:63-71. [PMID: 11886655 DOI: 10.1089/107632702753503063] [Citation(s) in RCA: 138] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Materials derived from extracellular matrices (ECMs) are being evaluated as scaffolds for surgical reconstruction of damaged or missing tissues. It is important to understand the susceptibility of these biological materials to bacterial infections. ECMs derived from porcine small intestinal submucosa (SIS) and urinary bladder submucosa (UBS) were found to possess antimicrobial activity. ECM extracts, obtained by digesting these acellular matrices in acetic acid, demonstrated antibacterial activity against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus. Antimicrobial activity was determined using a minimal inhibitory concentration assay. Bacteriostatic activity was detected at protein concentrations of ECM extracts equivalent to 0.77-1.60 mg/mL. ECM extracts were found to inhibit bacterial growth for up to at least 13 h. The resulting extracts consisted of water-soluble peptides and proteins with molecular weights ranging from <4 to >100 kDa and lower molecular weight compounds, as determined by size exclusion liquid chromatography.
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Affiliation(s)
- Ayda Sarikaya
- Laboratory of Renewable Resources Engineering, School of Veterinary Medicine, Purdue University, West Lafayette, Indiana 47907-1295, USA
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27
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Chen MK, Badylak SF. Small bowel tissue engineering using small intestinal submucosa as a scaffold. J Surg Res 2001; 99:352-8. [PMID: 11469910 DOI: 10.1006/jsre.2001.6199] [Citation(s) in RCA: 155] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND Small intestinal submucosa (SIS) is an extracellular matrix used in tissue engineering studies to create de novo abdominal wall, urinary bladder, tendons, blood vessels, and dura mater. The purpose of this study is to evaluate the feasibility of using SIS as a scaffold for small bowel regeneration in an in situ xenograft model. MATERIALS AND METHODS Twenty-three dogs had a partial defect created on the small bowel wall which was repaired with a SIS patch. Four dogs underwent small bowel resection with placement of an interposed tube of SIS. The animals were followed 2 weeks to 1 year. RESULTS Three of the 23 dogs with SIS placed as a patch died shortly after surgery due to leakage from the site. The other 20 dogs survived up to time of elective necropsy with no evidence of intestinal dysfunction. At necropsy, the bowel circumference in the patched area had no stenosis. Histological evaluation showed the presence of a mucosal epithelial layer, varying amount of smooth muscle, sheets of collagen, and a serosal covering. Architecturally, the layers were not well organized in the submucosal region. An abundance of inflammatory cells was present in the early postoperative period but receded with time. All 4 dogs with a tubular segment of SIS interposed had significant problems. One had partial obstruction at 1 month, and 3 died in the early postoperative period due to leakage. CONCLUSIONS This preliminary study suggests that SIS patches can be used for small bowel regeneration. Tubular segmental replacement is not feasible at this time.
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Affiliation(s)
- M K Chen
- Department of Surgery, University of Florida, Gainesville, FL 32610, USA.
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28
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Badylak S, Liang A, Record R, Tullius R, Hodde J. Endothelial cell adherence to small intestinal submucosa: an acellular bioscaffold. Biomaterials 1999; 20:2257-63. [PMID: 10614932 DOI: 10.1016/s0142-9612(99)00156-8] [Citation(s) in RCA: 123] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Degradable biomaterials to be used as scaffolds for tissue repair will ideally be able to support new blood vessel growth. The present study evaluated the adherence of human dermal microvascular endothelial cells (HMECs) to an acellular resorbable scaffold material derived from the small intestinal submucosa (SIS). HMECs were exposed to hydrated and dehydrated forms of SIS and to plastic surfaces coated with one of four different known components of the SIS extracellular matrix: collagen Type I, collagen Type IV, fibronectin, and laminin. Results showed that adherence of HMECs to hydrated SIS was greater than to any of the other tested surfaces (P < 0.05). Exposure of HMECs to either soluble collagen Type IV or soluble fibronectin prior to exposure of these cells to hydrated SIS showed only partial inhibition of HMEC attachment. We conclude that HMECs find hydrated SIS to be a suitable substrate for adherence and that dehydration of SIS adversely affects the ability of HMECs to adhere in vitro. The cause of HMEC adherence to SIS appears to be a combination of both its composition and architecture.
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Affiliation(s)
- S Badylak
- Department of Biomedical Engineering, Purdue University, West Lafayette, IN 47097-1296, USA
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29
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Roeder R, Wolfe J, Lianakis N, Hinson T, Geddes LA, Obermiller J. Compliance, elastic modulus, and burst pressure of small-intestine submucosa (SIS), small-diameter vascular grafts. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 1999; 47:65-70. [PMID: 10400882 DOI: 10.1002/(sici)1097-4636(199910)47:1<65::aid-jbm9>3.0.co;2-f] [Citation(s) in RCA: 116] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Small-intestine submucosa (SIS) is cell-free collagen, 100 mu thick, derived from the small intestine. It has been used as a vascular graft and has the highly desirable property of remodeling itself to become host tissue. To date there has been limited reporting on its preimplantation mechanical properties as a vascular graft. In this study, compliance, elastic modulus, and burst pressure have been measured on 5- and 8-mm SIS grafts. The compliance (percent of diameter increase for a pressure rise from 80 to 120 mmHg) was 4.6% av (range 2.9 to 8.6%) for the 5-mm grafts. For the 8-mm graft, the increase in diameter for the same pressure rise was 8.7% av (range 7.2 to 9.5%). The modulus of elasticity (E) increased exponentially with increasing pressure according to E = E(o)e(alphaP), where Eo is the zero-pressure modulus and alpha is the exponent that describes the rate of increase in E with pressure; the units for E, Eo, and P are g/cm2. The mean value for Eo was 4106 (g/cm2 range 1348-5601). The mean value for alpha was 0.0059 (range 0.0028-0.0125). At 100 mmHg, the mean value for E was 8.91 x 10(3) g/cm2 (range 1.02-8.80 x 10(3)). The mean burst pressure for 5.5-mm grafts was 3517 mm Hg (range 2069-4654). In terms of preimplant compliance, the small-diameter SIS graft is about (1/2) as compliant as the dog carotid artery, about four times more compliant than a typical vein graft, and more than an order of magnitude more compliant than synthetic vascular grafts.
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Affiliation(s)
- R Roeder
- Department of Biomedical Engineering, Purdue University, West Lafayette, Indiana 47907-1296, USA
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Cobb MA, Badylak SF, Janas W, Simmons-Byrd A, Boop FA. Porcine small intestinal submucosa as a dural substitute. SURGICAL NEUROLOGY 1999; 51:99-104. [PMID: 9952131 DOI: 10.1016/s0090-3019(97)00475-8] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND The continuing search for the ideal dural substitute is currently directed toward collagen preparations. Xenogeneic porcine small intestinal submucosa (SIS), a naturally occurring extracellular matrix rich in collagen, has been successfully used as a soft tissue graft in several body organ systems, including preliminary studies as a dural substitute in the rat. METHODS Eight dogs underwent temporoparietal craniotomy and dural resection with replacement by SIS. Five dogs had contralateral procedures without SIS grafting. Three dogs had contralateral SIS grafts placed 2 months after the initial procedure. Histologic assessment was obtained at 7, 30, 60, 90, and 120 days. Cerebrospinal fluid (CSF) cytological examination and routine serum chemistry preceded sacrifice. RESULTS Histologic evaluation showed initial graft infiltration by mononuclear round cells, spindle-shaped cells within an eosinophilic staining extracellular matrix, and neovascularity. Complete resorption of the graft was evident by 60 days. This pattern is consistent with the previously described incorporation and remodeling of the SIS graft at other sites. CSF cytology and routine serum chemistry at the time of sacrifice were normal. Response to repeat grafting was identical to that of initial exposure. There was no clinical or histologic evidence of sensitization or graft rejection. No evidence of adverse effect on the underlying cerebral cortex was observed. CONCLUSIONS Porcine small intestinal submucosa demonstrates a favorable biologic response as a dural substitute in the canine model. It is a promising biomaterial for dural replacement.
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Affiliation(s)
- M A Cobb
- Department of Neurosurgery, Yale University School of Medicine, New Haven, Connecticut 06520, USA
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Yoo JJ, Meng J, Oberpenning F, Atala A. Bladder augmentation using allogenic bladder submucosa seeded with cells. Urology 1998; 51:221-5. [PMID: 9495701 DOI: 10.1016/s0090-4295(97)00644-4] [Citation(s) in RCA: 393] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVES The search for a suitable material to reconstruct the genitourinary tract has been a challenging task. Bowel has been widely used for urinary tract reconstruction, despite its subsequent complications. We investigated the possibility of using allogenic bladder submucosa, a tissue consisting of nonimmunogenic acellular collagen, either with or without cells, as a material for bladder augmentation. METHODS Partial cystectomies were performed in 10 beagle dogs. Both urothelial and smooth muscle cells were harvested and expanded separately in 5 animals. The allogenic bladder submucosa obtained from sacrificed dogs was seeded with muscle cells on one side and urothelial cells on the opposite side. All beagles underwent cruciate cystotomies on the bladder dome. Augmentation cystoplasty was performed with the allogenic bladder submucosa seeded with cells in 5 animals and with the allogenic bladder submucosa without cells in 5. The augmented bladders were retrieved 2 and 3 months after augmentation. RESULTS Bladders augmented with the allogenic bladder submucosa seeded with cells showed a 99% increase in capacity compared with bladders augmented with the cell-free allogenic bladder submucosa, which showed only a 30% increase in capacity. All dogs showed a normal bladder compliance, as evidenced by urodynamic studies. Histologically, all retrieved bladders contained a normal cellular organization consisting of a urothelial lined lumen surrounded by submucosal tissue and smooth muscle. Immunocytochemical analyses confirmed the urothelial and muscle cell phenotype and showed the presence of nerve fibers. CONCLUSIONS These results show that allogenic bladder submucosa seeded with cells appears to be an excellent option as a biomaterial for bladder augmentation.
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Affiliation(s)
- J J Yoo
- Department of Urology, Children's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA
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Badylak SF, Tullius R, Kokini K, Shelbourne KD, Klootwyk T, Voytik SL, Kraine MR, Simmons C. The use of xenogeneic small intestinal submucosa as a biomaterial for Achilles tendon repair in a dog model. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 1995; 29:977-85. [PMID: 7593041 DOI: 10.1002/jbm.820290809] [Citation(s) in RCA: 329] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A study was conducted to evaluate the tissue response to a xenogeneic biomaterial when this material was used to repair an experimentally induced Achilles tendon defect in the dog. Twenty dogs had a 1.5 cm segmental defect of the Achilles tendon created surgically which was then repaired with acellular connective tissue derived from porcine small intestinal submucosa (SIS). The animals were sacrificed at 1, 2, 4, 8, 12, 16, 24, and 48 weeks and the neotendons examined for uniaxial longitudinal tensile strength, morphologic appearance, hydroxyproline (collagen) content, and disappearance of the originally implanted SIS material over time. The contralateral normal Achilles tendons served as controls as did four additional dogs that had a 1.5 cm segmental Achilles tendon defect created surgically without subsequent surgical repair with SIS. Results showed the SIS remodeled neotendons to be stronger than the musculotendinous origin or the boney insertion (> 1000 N) by 12 weeks after surgery and to consist of organized collagen-rich connective tissue similar to the contralateral normal tendons. The four dogs in which no SIS was implanted showed inferior strength at the comparable time points of 4, 8, 12, and 16 weeks. Immunohistochemical studies suggest that the SIS biomaterial becomes degraded within the first eight weeks and serves as a temporary scaffold around which the body deposits appropriate and organized connective tissue. SIS is a promising biomaterial worthy of further investigation for orthopedic soft tissue applications.
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Affiliation(s)
- S F Badylak
- Hillenbrand Biomedical Engineering Center, Purdue University, West Lafayette, Indiana 47907, USA
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Prevel CD, Eppley BL, McCarty M, Jackson JR, Voytik SL, Hiles MC, Badylak SF. Experimental evaluation of small intestinal submucosa as a microvascular graft material. Microsurgery 1994; 15:586-91; discussion 592-3. [PMID: 7830542 DOI: 10.1002/micr.1920150812] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The evaluation of porcine small intestine submucosa (SIS) in a microsurgical model was conducted using an interpositional graft in the rat femoral artery. The SIS grafts were fabricated from processed porcine material that was wrapped around a glass tube and oversewn longitudinally to produce a tubular structure. Of the 42 animals studied, 7 received grafts of untreated SIS (group I), 7 of the grafts were presoaked (PSH) in heparin (Group II), 7 animals were treated with systemic heparin prior to implantation of PSH-SIS (group III), 7 animals received SIS grafts crosslinked to heparin (group IV), 7 animals received SIS grafts crosslinked to urokinase (group V), and 7 animals received untreated autologous epigastric vein grafts (group VI). Patency was assessed postoperatively and selected grafts were evaluated by histology. All SIS grafts failed to maintain patency beyond the first postoperative hour. Histologic examination of the thrombosed graft surfaces revealed a smooth luminal surface with a thick layer of attached fibrin and platelets with a central occluding thrombus. The thickness of the induced fibrin layer appears to narrow intraluminal space significantly at the microvascular level. While having excellent success at vessel diameters greater than 3 mm, and in a variety of nonporcine animal models without xenographic rejection, SIS in this model was thrombogenic despite a favorable surface morphology as demonstrated by SEM. Even with use of heparin and urokinase SIS graft thrombosis occurred.
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Affiliation(s)
- C D Prevel
- Department of Surgery, Indiana University School of Medicine, Indianapolis
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Ferrand BK, Kokini K, Badylak SF, Geddes LA, Hiles MC, Morff RJ. Directional porosity of porcine small-intestinal submucosa. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 1993; 27:1235-41. [PMID: 8245038 DOI: 10.1002/jbm.820271004] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Small-intestinal submucosa (SIS) has been shown to be a promising biomaterial for vascular graft applications. This study examines the directionality property of SIS porosity using 35 SIS specimens from 13 pigs. In addition, the effects of the weight of the donor pig, pre-conditioning of 13 additional SIS specimens, and the duration of the test of five additional SIS specimens on such porosity are reported. The porosity from serosal to mucosal direction was found to be four times greater than the porosity in the opposite direction. The weight of the donor pig was not found to be an important factor in SIS porosity. Preconditioning served to increase the average serosal porosity index at 120 mm Hg static water pressure from 2.99 to 8.33 mL/(min cm2). The porosity in the mucosal direction was not affected by preconditioning. Porosity in both directions decreased with increasing test duration. The directionality property of SIS porosity may be an important factor in its success as a vascular graft. The term 'porosity' is used throughout this article, but current standards also refer to the term 'permeability' to describe the passage of liquid through a vascular graft.
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Affiliation(s)
- B K Ferrand
- School of Mechanical Engineering, Purdue University, W. Lafayette, IN 47907
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