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Eyni H, Ghorbani S, Nazari H, Hajialyani M, Razavi Bazaz S, Mohaqiq M, Ebrahimi Warkiani M, Sutherland DS. Advanced bioengineering of male germ stem cells to preserve fertility. J Tissue Eng 2021; 12:20417314211060590. [PMID: 34868541 PMCID: PMC8638075 DOI: 10.1177/20417314211060590] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Accepted: 11/01/2021] [Indexed: 12/22/2022] Open
Abstract
In modern life, several factors such as genetics, exposure to toxins, and aging have resulted in significant levels of male infertility, estimated to be approximately 18% worldwide. In response, substantial progress has been made to improve in vitro fertilization treatments (e.g. microsurgical testicular sperm extraction (m-TESE), intra-cytoplasmic sperm injection (ICSI), and round spermatid injection (ROSI)). Mimicking the structure of testicular natural extracellular matrices (ECM) outside of the body is one clear route toward complete in vitro spermatogenesis and male fertility preservation. Here, a new wave of technological innovations is underway applying regenerative medicine strategies to cell-tissue culture on natural or synthetic scaffolds supplemented with bioactive factors. The emergence of advanced bioengineered systems suggests new hope for male fertility preservation through development of functional male germ cells. To date, few studies aimed at in vitro spermatogenesis have resulted in relevant numbers of mature gametes. However, a substantial body of knowledge on conditions that are required to maintain and mature male germ cells in vitro is now in place. This review focuses on advanced bioengineering methods such as microfluidic systems, bio-fabricated scaffolds, and 3D organ culture applied to the germline for fertility preservation through in vitro spermatogenesis.
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Affiliation(s)
- Hossein Eyni
- Department of Anatomical Sciences,
School of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Sadegh Ghorbani
- Interdisciplinary Nanoscience Center
(iNANO), Aarhus University, Aarhus, Denmark
| | - Hojjatollah Nazari
- Research Center for Advanced
Technologies in Cardiovascular Medicine, Tehran Heart Center, Tehran University of
Medical Sciences, Tehran, Iran
| | - Marziyeh Hajialyani
- Pharmaceutical Sciences Research
Center, Health Institute, Kermanshah University of Medical Sciences, Kermanshah,
Iran
| | - Sajad Razavi Bazaz
- School of Biomedical Engineering,
University of Technology Sydney, Sydney, NSW, Australia
| | - Mahdi Mohaqiq
- Institute of Regenerative Medicine,
School of Medicine, Wake Forest University, Winston-Salem, NC, USA
| | | | - Duncan S Sutherland
- Interdisciplinary Nanoscience Center
(iNANO), Aarhus University, Aarhus, Denmark
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2
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Mohammadrezaei D, Golzar H, Rezai Rad M, Omidi M, Rashedi H, Yazdian F, Khojasteh A, Tayebi L. In vitroeffect of graphene structures as an osteoinductive factor in bone tissue engineering: A systematic review. J Biomed Mater Res A 2018; 106:2284-2343. [DOI: 10.1002/jbm.a.36422] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2018] [Revised: 03/13/2018] [Accepted: 03/26/2018] [Indexed: 12/13/2022]
Affiliation(s)
- Dorsa Mohammadrezaei
- School of Chemical Engineering, College of Engineering; University of Tehran; Tehran Iran
| | - Hossein Golzar
- School of Chemical Engineering, College of Engineering; University of Tehran; Tehran Iran
| | - Maryam Rezai Rad
- Department of Tissue Engineering, School of Advanced Technologies in Medicine; Shahid Beheshti University of Medical Sciences; Tehran Iran
- Dental Research Center, Research Institute of Dental Sciences, School of Dentistry, Shahid Beheshti University of Medical Sciences; Tehran Iran
| | - Meisam Omidi
- Protein Research Center, Shahid Beheshti University, GC, Velenjak; Tehran Iran
| | - Hamid Rashedi
- School of Chemical Engineering, College of Engineering; University of Tehran; Tehran Iran
| | - Fatemeh Yazdian
- Department of Life Science Engineering; Faculty of New Science and Technologies, University of Tehran; Tehran Iran
| | - Arash Khojasteh
- Department of Tissue Engineering, School of Advanced Technologies in Medicine; Shahid Beheshti University of Medical Sciences; Tehran Iran
- Department of Oral and Maxillofacial Surgery; Shahid Beheshti University of Medical Sciences, Tehran; Tehran Iran
| | - Lobat Tayebi
- Biomaterials and Advanced Drug Delivery Laboratory, School of Medicine; Stanford University; Palo Alto California
- Marquette University School of Dentistry; Milwaukee Wisconsin
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Tian Z, Huang L, Pei X, Chen J, Wang T, Yang T, Qin H, Sui L, Wang J. Electrochemical synthesis of three-dimensional porous reduced graphene oxide film: Preparation and in vitro osteogenic activity evaluation. Colloids Surf B Biointerfaces 2017; 155:150-158. [DOI: 10.1016/j.colsurfb.2017.04.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2016] [Revised: 03/30/2017] [Accepted: 04/05/2017] [Indexed: 12/25/2022]
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4
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Boire TC, Balikov DA, Lee Y, Guth CM, Cheung-Flynn J, Sung HJ. Biomaterial-Based Approaches to Address Vein Graft and Hemodialysis Access Failures. Macromol Rapid Commun 2016; 37:1860-1880. [PMID: 27673474 PMCID: PMC5156561 DOI: 10.1002/marc.201600412] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 08/15/2016] [Indexed: 12/19/2022]
Abstract
Veins used as grafts in heart bypass or as access points in hemodialysis exhibit high failure rates, thereby causing significant morbidity and mortality for patients. Interventional or revisional surgeries required to correct these failures have been met with limited success and exorbitant costs, particularly for the US Centers for Medicare & Medicaid Services. Vein stenosis or occlusion leading to failure is primarily the result of neointimal hyperplasia. Systemic therapies have achieved little long-term success, indicating the need for more localized, sustained, biomaterial-based solutions. Numerous studies have demonstrated the ability of external stents to reduce neointimal hyperplasia. However, successful results from animal models have failed to translate to the clinic thus far, and no external stent is currently approved for use in the US to prevent vein graft or hemodialysis access failures. This review discusses current progress in the field, design considerations, and future perspectives for biomaterial-based external stents. More comparative studies iteratively modulating biomaterial and biomaterial-drug approaches are critical in addressing mechanistic knowledge gaps associated with external stent application to the arteriovenous environment. Addressing these gaps will ultimately lead to more viable solutions that prevent vein graft and hemodialysis access failures.
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Affiliation(s)
- Timothy C Boire
- Department of Biomedical Engineering, Vanderbilt University, 37235, Nashville, TN, USA
| | - Daniel A Balikov
- Department of Biomedical Engineering, Vanderbilt University, 37235, Nashville, TN, USA
| | - Yunki Lee
- Department of Biomedical Engineering, Vanderbilt University, 37235, Nashville, TN, USA
| | - Christy M Guth
- Division of Vascular Surgery, Department of Surgery, Vanderbilt University Medical Center, Nashville, TN, 37235, USA
| | - Joyce Cheung-Flynn
- Division of Vascular Surgery, Department of Surgery, Vanderbilt University Medical Center, Nashville, TN, 37235, USA
| | - Hak-Joon Sung
- Department of Biomedical Engineering, Vanderbilt University, 37235, Nashville, TN, USA
- Severance Biomedical Science Institute, College of Medicine, Yonsei University, Seoul, 120-752, Republic of Korea
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Huang WY, Yeh CL, Lin JH, Yang JS, Ko TH, Lin YH. Development of fibroblast culture in three-dimensional activated carbon fiber-based scaffold for wound healing. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2012; 23:1465-1478. [PMID: 22415364 DOI: 10.1007/s10856-012-4608-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2011] [Accepted: 02/28/2012] [Indexed: 05/31/2023]
Abstract
This work developed a novel bi-layer wound dressing composed of 3D activated carbon fibers that allows facilitates fibroblast cell growth and migration to a wound site for tissue reconstruction, and the gentamicin is incorporated into a poly(γ-glutamic acid)/gelatin membrane to prevent bacterial infection. In an in vitro, field emission scanning electron microscopy shows that rat skin fibroblasts appeared and spread on the surface of activated carbon fibers, and penetrated the interior and exterior of the 3D activated carbon fiber construct to a depth of roughly 200 μm. An in vivo analysis shows that fibroblast cells containing the proposed 3D scaffold had the potential of a biologically functionalized dressing to accelerate wound closure. Additionally, fibroblasts migrated to the wound site in a bi-layer wound dressing containing fibroblasts, enhancing fibronectin and type I collagen expression, resulting in faster skin regeneration than that achieved with a Tegaderm™ hydrocolloid dressing or gauze.
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Affiliation(s)
- Wen-Ying Huang
- Department of Applied Cosmetology and Graduate Institute of Cosmetic Science, Hungkuang University, Taichung, Taiwan
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Park IS, Kim SH, Kim YH, Kim IH, Kim SH. A Collagen/Smooth Muscle Cell-Incorporated Elastic Scaffold for Tissue-Engineered Vascular Grafts. JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION 2012; 20:1645-60. [DOI: 10.1163/156856208x386237] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- In Su Park
- a Biomaterials Research Center, Korea Institute of Science and Technology, P.O. Box 131, Cheongryang, Seoul 130-650, South Korea; School of Life Science and Biotechnology, Korea University, Seoul 136-701, South Korea
| | - Sang-Heon Kim
- b Biomaterials Research Center, Korea Institute of Science and Technology, P.O. Box 131, Cheongryang, Seoul 130-650, South Korea
| | - Young Ha Kim
- c Department of Materials Science & Engineering, Gwangju Institute of Science and Technology, 1 Oryong-dong, Buk-ku, Gwangju 500-712, South Korea
| | - Ik Hwan Kim
- d School of Life Science and Biotechnology, Korea University, Seoul 136-701, South Korea
| | - Soo Hyun Kim
- e Biomaterials Research Center, Korea Institute of Science and Technology, P.O. Box 131, Cheongryang, Seoul 130-650, South Korea
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Haroun AA, Gamal-Eldeen A, Harding DRK. Preparation, characterization and in vitro biological study of biomimetic three-dimensional gelatin-montmorillonite/cellulose scaffold for tissue engineering. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2009; 20:2527-2540. [PMID: 19629650 DOI: 10.1007/s10856-009-3818-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2009] [Accepted: 07/01/2009] [Indexed: 05/28/2023]
Abstract
This work focused on studying the effect of blending gelatin (Gel) with Cellulose (Cel), in the presence of montmorillonite (MMT), on the swelling behavior, in vitro degradation and surface morphology. Additionally, the effect of the prepared biocomposites on the characteristics of the human osteosarcoma cells (Saos-2), including proliferation, scaffold/cells interactions, apoptosis and their potential of the cells to induce osteogenesis and differentiation was evaluated. The crosslinked biocomposites with glutaraldehyde (GA) or N,N-methylene-bisacrylamide (MBA) was prepared via an intercalation process and freeze-drying technique. Properties including SEM morphology, X-ray diffraction characterization and in vitro biodegradation were investigated. The successful generation of 3-D biomimetic porous scaffolds incorporating Saos-2 cells indicated their potential for de novo bone formation that exploits cell-matrix interactions. In vitro studies revealed that the scaffolds containing 12 and 6% MMT crosslinked by 5 and 0.5% GA seem to be the two most efficient and effective biodegradable scaffolds, which promoted Saos-2 cells proliferation, migration, expansion, adhesion, penetration, spreading, and differentiation, respectively. MMT improved cytocompatibility between the osteoblasts and the biocomposite. In vitro analysis indicated good biocompatibility of the scaffold and presents the scaffold as a new potential candidate as suitable biohybrid material for tissue engineering.
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Affiliation(s)
- Ahmed A Haroun
- Chemical Industries Research Division, Center of Excellency for Advanced Sciences, National Research Centre, Dokki, Cairo, Egypt.
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8
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Preparation of biodegradable chitin/gelatin membranes with GlcNAc for tissue engineering applications. Carbohydr Polym 2008. [DOI: 10.1016/j.carbpol.2007.12.011] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Jeremy JY, Gadsdon P, Shukla N, Vijayan V, Wyatt M, Newby AC, Angelini GD. On the biology of saphenous vein grafts fitted with external synthetic sheaths and stents. Biomaterials 2006; 28:895-908. [PMID: 17113144 DOI: 10.1016/j.biomaterials.2006.10.023] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2006] [Accepted: 10/10/2006] [Indexed: 02/01/2023]
Abstract
Autologous saphenous vein is used as a conduit to bypass atherosclerotic lesions in both the coronary artery (coronary artery bypass graft surgery [CABG]) and in femoral arteries (infrainguinal bypass graft surgery [IIBS]). Despite the undoubted success and benefits of the procedures, graft failure occurs in 50% of cases within 10 years after surgery. A principal cause of late vein graft failure is intimal and medial hyperplasia and superimposed atherogenesis. Apart from lipid lowering therapy, no intervention has hitherto proved clinically effective in preventing late vein graft failure which clearly constitutes a major clinical and economic problem that needs to be urgently resolved. However, we have studied the effect of external synthetic stents and sheaths in pig models of vein into artery interposition grafting and found them to have a profound effect on vein graft remodelling and thickening. In this review, therefore, we will summarise the mechanisms underlying vein graft failure and how these stents influence these processes and the possible mechanisms involved as well as the application of these devices in preventing vein graft failure clinically.
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11
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Solchaga LA, Tognana E, Penick K, Baskaran H, Goldberg VM, Caplan AI, Welter JF. A rapid seeding technique for the assembly of large cell/scaffold composite constructs. ACTA ACUST UNITED AC 2006; 12:1851-63. [PMID: 16889515 PMCID: PMC1858629 DOI: 10.1089/ten.2006.12.1851] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
These studies address critical technical issues involved in creating human mesenchymal stem cell (hMSC)/ scaffold implants for cartilage repair. These issues include obtaining a high cell density and uniform spatial cell distribution within the scaffold, factors that are critical in the initiation and homogeneity of chondrogenic differentiation. For any given scaffold, the initial seeding influences cell density, retention, and spatial distribution within the scaffold, which eventually will affect the function of the construct. Here, we discuss the development of a vacuum-aided seeding technique for HYAFF -11 sponges which we compared to passive infiltration. Our results show that, under the conditions tested, hMSCs were quantitatively and homogeneously loaded into the scaffolds with 90+% retention rates after 24 h in perfusion culture with no negative effect on cell viability or chondrogenic potential. The retention rates of the vacuum-seeded constructs were at least 2 times greater than those of passively seeded constructs at 72 h. Histomorphometric analysis revealed that the core of the vacuum-seeded constructs contained 240% more cells than the core of passively infiltrated scaffolds. The vacuum seeding technique is safe, rapid, reproducible, and results in controlled quantitative cell loading, high retention, and uniform distribution.
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Affiliation(s)
- Luis A Solchaga
- Department of Orthopaedics, Case western Reserve university Cleveland, Ohio 44106-7080, USA
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12
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Vijayan V, Shukla N, Johnson JL, Gadsdon P, Angelini GD, Smith FCT, Baird R, Jeremy JY. Long-term reduction of medial and intimal thickening in porcine saphenous vein grafts with a polyglactin biodegradable external sheath. J Vasc Surg 2004; 40:1011-9. [PMID: 15557918 DOI: 10.1016/j.jvs.2004.08.047] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
OBJECTIVES The development of neointimal hyperplasia with subsequent atherosclerotic deposition has been proposed to cause most late vein graft failures. Our unit has previously demonstrated that placement of a macroporous, loose-fitting polyester external stent prevents neointimal thickening in porcine vein grafts, and has been proposed as a therapeutic strategy to prevent late vein graft failure. To reduce any potential long-term complications of the permanent polyester stent, a study was undertaken to investigate the effect of a biodegradable external stent on porcine vein graft thickening at 1 month and to identify its longer term effects at 6 months. METHODS Bilateral saphenous vein to common carotid artery interposition grafting was performed in Large White pigs (25-32 kg; n = 6 per time course group) according to UK Home Office guidelines. A commercially constructed loose-fitting 8-mm-diameter polyglactin stent was placed externally around the vein graft on one side, and the contralateral side remained unstented to serve as control. The external stent was designed to biodegrade and hence disappear within 90 days. Grafts were left in situ for 1 month in 1 group of animals, and for up to 6 months in the other group, before explantation. Graft morphometric features were assessed with computer-aided planimetry. RESULTS At 1 month the vein grafts fitted with the polyglactin stent demonstrated a statistically significant decrease in neointimal thickening (0.038 mm; interquartile range [IQR], 0.035-0.039 mm) compared with the unstented control grafts (0.13 mm; IQR; 0.11-0.19; P = .0012), and also in medial thickening (0.09 mm; IQR, 0.086-0.093) compared with unsheathed control grafts (0.302 mm; IQR, 0.272-0.414; P = .0012). The 6-month polyglactin stented grafts also demonstrated a statistically significant reduction in neointimal thickening (0.049 mm; IQR, 0.047-0.07; P = .0012) compared with control grafts (0.178 mm; IQR, 0.164-0.19), and also in medial thickening (0.105 mm; IQR, 0.095-0.143) compared with unstented grafts (0.421 mm; IQR, 0.35-0.44; P = .0012, Mann-Whitney U test). CONCLUSION The loose-fitting biodegradable polyglactin external stent reduces porcine vein graft thickening at 1 month, which persists in the long term, even after degradation of the stent itself. This effective removal of the stent may therefore reduce the long-term risks for infection and mechanical complications associated with implanted prosthetic material while still eliciting the primary objective of preventing graft thickening over the long term. Biodegradable external stents therefore have potential advantages over permanent stent material in clinical application. CLINICAL RELEVANCE Arteriovenous bypass graft failure has a huge economic effect on health care resources, and a devastating effect o the patient. The attenuation of vein wall thickening, with subsequent luminal narrowing and occlusion, is a major goal in improving the longevity of the venous graft, to reduce secondary percutaneous and surgical interventions. The biodegradable external stent demonstrated in this study has possible clinical applications in bypass procedures with autogenous venous tissue, and represents a novel approach to ameliorating the problem of intimal hyperplasia that plagues these grafts.
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Affiliation(s)
- Vikram Vijayan
- Vascular Unit, The Bristol Royal Infirmary, Bristol BS2 8HW, UK.
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Jeremy JY, Bulbulia R, Johnson JL, Gadsdon P, Vijayan V, Shukla N, Smith FCT, Angelini GD. A bioabsorbable (polyglactin), nonrestrictive, external sheath inhibits porcine saphenous vein graft thickening. J Thorac Cardiovasc Surg 2004; 127:1766-72. [PMID: 15173735 DOI: 10.1016/j.jtcvs.2003.09.054] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE External, nonrestrictive, macro-porous polyester stents prevent neointima formation in porcine vein grafts and have been proposed as a therapeutic approach to the prevention of late vein graft failure. These stents are nonbiodegradable and therefore may promote long-term foreign body problems including infection and inflammation. The effect of external macro-porous biodegradable (polyglactin) sheaths on neointimal and medial thickening in porcine vein grafts was therefore investigated. METHODS Bilateral saphenous vein-carotid artery interposition grafting was performed in white Landrace pigs (n = 8) with external placement of polyglactin (Vicryl) sheaths (8 mm in diameter) on 1 side, with the contralateral side acting as a control. One month after surgery, grafts were explanted and wall dimensions measured on histological sections using computer-aided planimetry, and an immunocytochemical appraisal was carried out. RESULTS All grafts were patent at explantation. Polyglactin sheaths significantly reduced intimal thickness, medial thickness, and the percentage of proliferating cells compared with unsheathed controls. There was a pronounced accumulation of macrophages, giant cells, endothelial cells, and microvessels within and surrounding the biodegradable sheath compared with controls. CONCLUSIONS A nonrestrictive, biodegradable (polyglactin), external sheath reduces medial and intimal thickening in experimental saphenous vein grafts, possibly through inflammatory cell-mediated angiogenesis. If subsequent long-term studies confirm preservation of this beneficial effect, once the sheath biodegrades, this approach may have an advantage over the permanent polyester stent when applied clinically.
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Affiliation(s)
- Jamie Y Jeremy
- The Bristol Heart Institute, Bristol Royal Infirmary, University of Bristol, Bristol, UK.
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Bhattarai SR, Bhattarai N, Yi HK, Hwang PH, Cha DI, Kim HY. Novel biodegradable electrospun membrane: scaffold for tissue engineering. Biomaterials 2004; 25:2595-602. [PMID: 14751745 DOI: 10.1016/j.biomaterials.2003.09.043] [Citation(s) in RCA: 326] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Nonwoven fibrous matrixes have been widely used as scaffolds in tissue engineering, and modification of microstructure of these matrices is needed to organize cells in three-dimensional space with spatially balanced proliferation and differentiation required for functional tissue development. The objective of this study was fabrication of nanofibrous matrix from novel biodegradable poly(p-dioxanone-co-L-lactide)-block-poly(ethylene glycol) (PPDO/PLLA-b-PEG) copolymer, and to examine cell proliferation, morphology of cell-matrix interaction with the electrospun nanofibrous matrix. The electrospun structure composed of PPDO/PLLA-b-PEG fibers with an average diameters of 380 nm, median pore size 8 microm, porosity more than 80% and mechanical strength 1.4 MPa, is favorable for cell-matrix interaction and supports the active biocompatibility of the structure. NIH 3T3 fibroblast cell seeded on the structure tend to maintain phenotypic shape and guided growth according to nanofiber orientation. Good capability of the nanofibrous structure for supporting the cell attachment and proliferation are observed. This novel biodegradable scaffold will be applicable for tissue engineering based upon its unique architecture, which acts to support and guide cell growth.
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Affiliation(s)
- Shanta Raj Bhattarai
- Department of Bioprocess Engineering, Chonbuk National University, Chonju 561-756, South Korea
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15
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Effects of three-dimensional scaffolds on cell organization and tissue development. BIOTECHNOL BIOPROC E 2001. [DOI: 10.1007/bf02932999] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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Li Y, Ma T, Kniss DA, Yang ST, Lasky LC. Human cord cell hematopoiesis in three-dimensional nonwoven fibrous matrices: in vitro simulation of the marrow microenvironment. JOURNAL OF HEMATOTHERAPY & STEM CELL RESEARCH 2001; 10:355-68. [PMID: 11454311 DOI: 10.1089/152581601750288966] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Current hematopoietic culture systems mainly utilize two-dimensional devices with limited ability to promote self-renewal of early progenitors. In vivo-like three-dimensional (3-D) culture environments might be conducive to regulating stem cell proliferation and differentiation similar to in vivo hematopoiesis. The few 3-D cultures reported in the literature either produced few progenitors or provided little information about microenvironment. In this study, we constructed a 3-D hematopoietic microenvironment composed of nonwoven matrix and human cord blood (CB) cells to simulate the marrow microenvironment and expand cord progenitors. Nonwoven polyethylene terephthalate (PET) fabric with defined microstructure was used as the 3-D scaffold and the PET surface was modified by hydrolysis to improve cell adhesion. Different cell organizations were formed in a 3-D matrix in a developmental manner, from individual cells and cells bridging between fibers to large cell aggregates. Both stromal and hematopoietic cells were distributed spatially within the scaffold. Compared to two-dimensional (2-D) CD34(+) cell culture, 3-D culture produced 30-100% higher total cells and progenitors without exogenous cytokines. With thrombopoietin and flt-3/flk-2 ligand, it supported two- to three-fold higher total cell number (62.1- vs. 24.6-fold), CD34(+) cell number (6.8- vs. 2.8-fold) and colony-forming unit (CFU) number for 7-9 weeks (n = 6), indicating a hematopoiesis pathway that promoted progenitor production. Culture in 3-D nonwoven matrices enhanced cell-cell and cell-matrix interactions and allowed 3-D distribution of stromal and hematopoietic cells. The formation of cell aggregates and higher progenitor content indicated that the spatial microenvironment in 3-D culture played an important role in promoting hematopoiesis. This 3-D culture system can be used as an in vitro model to study stem cell or progenitor behavior, and to achieve sustained progenitor expansion.
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Affiliation(s)
- Y Li
- Department of Chemical Engineering, The Ohio State University, Columbus, OH 43210, USA
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Li Y, Ma T, Yang ST, Kniss DA. Thermal compression and characterization of three-dimensional nonwoven PET matrices as tissue engineering scaffolds. Biomaterials 2001; 22:609-18. [PMID: 11219726 DOI: 10.1016/s0142-9612(00)00224-6] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Nonwoven fibrous matrices have been widely used as scaffolds in tissue engineering, and modification of microstructure of these matrices is needed to organize cells in three-dimensional space with spatially balanced proliferation and differentiation required for functional tissue development. The method of thermal compression of nonwoven polyethylene terephthalate (PET) fabrics was developed and key parameters of temperature, pressure, and compression duration were evaluated in this study. The permanent deformation was obtained at elevated temperature under pressure and the viscoelastic compressional behaviors were observed, characterized by a distinct apparent modulus change in glass transition temperature region. A liquid extrusion method was further employed to analyze both pore size and its distribution for matrices with porosity ranging from 84 to 93%. It is also found that a more uniformly distributed pore size was resulted from thermal compression and the isotropic nature of nonwoven fabrics was preserved because of the proportional reduction of the pore by compression. The thermally compressed fabric matrices with two different pore sizes (15 and 20 microm in pore radius) were used to culture human trophoblast ED27 and NIH 3T3 cells. It was found that cells cultured in the different pore-size PET matrices had different cell spatial organization and proliferation rates. The smaller pores in the matrix allowed cells to spread better and proliferate faster, while cells in the larger pores tended to form large aggregates and had lower proliferation rate. The thermal compression technique also can be applied to other synthetic fibrous matrices including biodegradable polymers used in tissue engineering to modify the microstructure according to their viscoelastic properties.
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Affiliation(s)
- Y Li
- Department of Chemical Engineering, The Ohio State University, Columbus 43210, USA
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Sousa-Escandón A. "Sandwich technique" for suburethral placement of Mersilene mesh sling during pubovaginal suspension surgery: preliminary results. Urology 2001; 57:49-54. [PMID: 11164142 DOI: 10.1016/s0090-4295(00)00865-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVES To evaluate the effectiveness of a new "sandwich technique" for heterologous sling placement during pubovaginal suspension for treatment of recurrent stress urinary incontinence. METHODS A new sling placement procedure was used in 31 women (mean age 65.4 years) who had undergone multiple operations. With this technique, a heterologous sling was placed without dissection over a de-epithelialized vaginal wall and later covered with a vaginal wall flap. Finally, the sling and the bladder neck were suspended from the pubic bone with metallic anchorages and nonabsorbable sutures. RESULTS The objective success rates for SUI resolution was 87.1% but, subjectively, 90.3% of patients were satisfied or very satisfied with the procedure. The median follow-up time was 34 months. Morbidity was minimal, and the mean hospitalization time was less than 5 days. CONCLUSIONS This original, simple, noninvasive treatment is applicable to all type II and type III SUI with or without associated cystoceles, regardless of patient age or sexual activity, and has shown encouraging results. This procedure is highly recommended for the treatment of SUI, especially in patients who have undergone multiple previous operations.
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Affiliation(s)
- A Sousa-Escandón
- Servicio de Urología, Hospital Comarcal de Monforte, Lugo, Spain
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Coda A, Botto-Micca F, Quaglino F, Ramellini G. In vivo tissue reaction to different prosthetic materials in abdominal wall hernia repair. Hernia 2000. [DOI: 10.1007/bf01201068] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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