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Yap KK, Schröder J, Gerrand YW, Dobric A, Kong AM, Fox AM, Knowles B, Banting SW, Elefanty AG, Stanley EG, Yeoh GC, Lockwood GP, Cogger VC, Morrison WA, Polo JM, Mitchell GM. Liver specification of human iPSC-derived endothelial cells transplanted into mouse liver. JHEP Rep 2024; 6:101023. [PMID: 38681862 PMCID: PMC11046210 DOI: 10.1016/j.jhepr.2024.101023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 01/19/2024] [Accepted: 01/23/2024] [Indexed: 05/01/2024] Open
Abstract
Background & Aims Liver sinusoidal endothelial cells (LSECs) are important in liver development, regeneration, and pathophysiology, but the differentiation process underlying their tissue-specific phenotype is poorly understood and difficult to study because primary human cells are scarce. The aim of this study was to use human induced pluripotent stem cell (hiPSC)-derived LSEC-like cells to investigate the differentiation process of LSECs. Methods hiPSC-derived endothelial cells (iECs) were transplanted into the livers of Fah-/-/Rag2-/-/Il2rg-/- mice and assessed over a 12-week period. Lineage tracing, immunofluorescence, flow cytometry, plasma human factor VIII measurement, and bulk and single cell transcriptomic analysis were used to assess the molecular and functional changes that occurred following transplantation. Results Progressive and long-term repopulation of the liver vasculature occurred as iECs expanded along the sinusoids between hepatocytes and increasingly produced human factor VIII, indicating differentiation into LSEC-like cells. To chart the developmental profile associated with LSEC specification, the bulk transcriptomes of transplanted cells between 1 and 12 weeks after transplantation were compared against primary human adult LSECs. This demonstrated a chronological increase in LSEC markers, LSEC differentiation pathways, and zonation. Bulk transcriptome analysis suggested that the transcription factors NOTCH1, GATA4, and FOS have a central role in LSEC specification, interacting with a network of 27 transcription factors. Novel markers associated with this process included EMCN and CLEC14A. Additionally, single cell transcriptomic analysis demonstrated that transplanted iECs at 4 weeks contained zonal subpopulations with a region-specific phenotype. Conclusions Collectively, this study confirms that hiPSCs can adopt LSEC-like features and provides insight into LSEC specification. This humanised xenograft system can be applied to further interrogate LSEC developmental biology and pathophysiology, bypassing current logistical obstacles associated with primary human LSECs. Impact and implications Liver sinusoidal endothelial cells (LSECs) are important cells for liver biology, but better model systems are required to study them. We present a pluripotent stem cell xenografting model that produces human LSEC-like cells. A detailed and longitudinal transcriptomic analysis of the development of LSEC-like cells is included, which will guide future studies to interrogate LSEC biology and produce LSEC-like cells that could be used for regenerative medicine.
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Affiliation(s)
- Kiryu K. Yap
- O’Brien Department of St Vincent’s Institute, Fitzroy, VIC, Australia
- University of Melbourne Department of Surgery, St Vincent’s Hospital Melbourne, Fitzroy, VIC, Australia
| | - Jan Schröder
- Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC, Australia
- Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
- Australian Regenerative Medicine Institute, Clayton, VIC, Australia
- Doherty Institute & University of Melbourne Department of Microbiology and Immunology, Parkville, VIC, Australia
| | - Yi-Wen Gerrand
- O’Brien Department of St Vincent’s Institute, Fitzroy, VIC, Australia
| | - Aleksandar Dobric
- O’Brien Department of St Vincent’s Institute, Fitzroy, VIC, Australia
| | - Anne M. Kong
- O’Brien Department of St Vincent’s Institute, Fitzroy, VIC, Australia
| | - Adrian M. Fox
- University of Melbourne Department of Surgery, St Vincent’s Hospital Melbourne, Fitzroy, VIC, Australia
- Hepatobiliary Surgery Unit, St Vincent’s Hospital Melbourne, Fitzroy, VIC, Australia
| | - Brett Knowles
- University of Melbourne Department of Surgery, St Vincent’s Hospital Melbourne, Fitzroy, VIC, Australia
- Hepatobiliary Surgery Unit, St Vincent’s Hospital Melbourne, Fitzroy, VIC, Australia
| | - Simon W. Banting
- University of Melbourne Department of Surgery, St Vincent’s Hospital Melbourne, Fitzroy, VIC, Australia
- Hepatobiliary Surgery Unit, St Vincent’s Hospital Melbourne, Fitzroy, VIC, Australia
| | - Andrew G. Elefanty
- Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC, Australia
- Murdoch Children's Research Institute, The Royal Children's Hospital, Flemington Road, Parkville, VIC, Australia
- Department of Paediatrics, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, VIC, Australia
| | - Eduoard G. Stanley
- Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC, Australia
- Murdoch Children's Research Institute, The Royal Children's Hospital, Flemington Road, Parkville, VIC, Australia
- Department of Paediatrics, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, VIC, Australia
| | - George C. Yeoh
- Harry Perkins Institute of Medical Research and Centre for Medical Research, University of Western Australia, Perth, WA, Australia
| | - Glen P. Lockwood
- ANZAC Research Institute and University of Sydney, Concord, NSW, Australia
| | - Victoria C. Cogger
- ANZAC Research Institute and University of Sydney, Concord, NSW, Australia
| | - Wayne A. Morrison
- O’Brien Department of St Vincent’s Institute, Fitzroy, VIC, Australia
- University of Melbourne Department of Surgery, St Vincent’s Hospital Melbourne, Fitzroy, VIC, Australia
- Australian Catholic University, Fitzroy, VIC, Australia
| | - Jose M. Polo
- Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC, Australia
- Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
- Australian Regenerative Medicine Institute, Clayton, VIC, Australia
- Adelaide Centre for Epigenetics, South Australian Immunogenomics Cancer Institute, University of Adelaide, Adelaide, SA, Australia
| | - Geraldine M. Mitchell
- O’Brien Department of St Vincent’s Institute, Fitzroy, VIC, Australia
- University of Melbourne Department of Surgery, St Vincent’s Hospital Melbourne, Fitzroy, VIC, Australia
- Australian Catholic University, Fitzroy, VIC, Australia
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Davies EM, Gurung R, Le KQ, Roan KT, Harvey RP, Mitchell GM, Schwarz Q, Mitchell CA. PI(4,5)P 2-dependent regulation of endothelial tip cell specification contributes to angiogenesis. Sci Adv 2023; 9:eadd6911. [PMID: 37000875 PMCID: PMC10065449 DOI: 10.1126/sciadv.add6911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Accepted: 02/24/2023] [Indexed: 06/19/2023]
Abstract
Dynamic positioning of endothelial tip and stalk cells, via the interplay between VEGFR2 and NOTCH signaling, is essential for angiogenesis. VEGFR2 activates PI3K, which phosphorylates PI(4,5)P2 to PI(3,4,5)P3, activating AKT; however, PI3K/AKT does not direct tip cell specification. We report that PI(4,5)P2 hydrolysis by the phosphoinositide-5-phosphatase, INPP5K, contributes to angiogenesis. INPP5K ablation disrupted tip cell specification and impaired embryonic angiogenesis associated with enhanced DLL4/NOTCH signaling. INPP5K degraded a pool of PI(4,5)P2 generated by PIP5K1C phosphorylation of PI(4)P in endothelial cells. INPP5K ablation increased PI(4,5)P2, thereby releasing β-catenin from the plasma membrane, and concurrently increased PI(3,4,5)P3-dependent AKT activation, conditions that licensed DLL4/NOTCH transcription. Suppression of PI(4,5)P2 in INPP5K-siRNA cells by PIP5K1C-siRNA, restored β-catenin membrane localization and normalized AKT signaling. Pharmacological NOTCH or AKT inhibition in vivo or genetic β-catenin attenuation rescued angiogenesis defects in INPP5K-null mice. Therefore, PI(4,5)P2 is critical for β-catenin/DLL4/NOTCH signaling, which governs tip cell specification during angiogenesis.
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Affiliation(s)
- Elizabeth M. Davies
- Cancer Program, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Victoria 3800, Australia
| | - Rajendra Gurung
- Cancer Program, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Victoria 3800, Australia
| | - Kai Qin Le
- Cancer Program, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Victoria 3800, Australia
| | - Katherine T. T. Roan
- Cancer Program, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Victoria 3800, Australia
| | - Richard P. Harvey
- Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales 2010, Australia
- School of Clinical Medicine and School of Biotechnology and Biomolecular Science, University of New South Wales, Kensington, New South Wales 2052, Australia
| | - Geraldine M. Mitchell
- O’Brien Institute Department of St Vincent’s Institute and University of Melbourne, Department of Surgery, St. Vincent’s Hospital, Fitzroy, Victoria 3065, Australia
- Health Sciences Faculty, Australian Catholic University, Fitzroy, Victoria 3065, Australia
| | - Quenten Schwarz
- Centre for Cancer Biology, SA Pathology and University of South Australia, Adelaide, South Australia 5001, Australia
| | - Christina A. Mitchell
- Cancer Program, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Victoria 3800, Australia
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Kong AM, Lim SY, Palmer JA, Rixon A, Gerrand YW, Yap KK, Morrison WA, Mitchell GM. Engineering transplantable human lymphatic and blood capillary networks in a porous scaffold. J Tissue Eng 2022; 13:20417314221140979. [PMID: 36600999 PMCID: PMC9806376 DOI: 10.1177/20417314221140979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 11/08/2022] [Indexed: 12/27/2022] Open
Abstract
Due to a relative paucity of studies on human lymphatic assembly in vitro and subsequent in vivo transplantation, capillary formation and survival of primary human lymphatic (hLEC) and blood endothelial cells (hBEC) ± primary human vascular smooth muscle cells (hvSMC) were evaluated and compared in vitro and in vivo. hLEC ± hvSMC or hBEC ± hvSMC were seeded in a 3D porous scaffold in vitro, and capillary percent vascular volume (PVV) and vascular density (VD)/mm2 assessed. Scaffolds were also transplanted into a sub-cutaneous rat wound with morphology/morphometry assessment. Initially hBEC formed a larger vessel network in vitro than hLEC, with interconnected capillaries evident at 2 days. Interconnected lymphatic capillaries were slower (3 days) to assemble. hLEC capillaries demonstrated a significant overall increase in PVV (p = 0.0083) and VD (p = 0.0039) in vitro when co-cultured with hvSMC. A similar increase did not occur for hBEC + hvSMC in vitro, but hBEC + hvSMC in vivo significantly increased PVV (p = 0.0035) and VD (p = 0.0087). Morphology/morphometry established that hLEC vessels maintained distinct cell markers, and demonstrated significantly increased individual vessel and network size, and longer survival than hBEC capillaries in vivo, and established inosculation with rat lymphatics, with evidence of lymphatic function. The porous polyurethane scaffold provided advantages to capillary network formation due to its large (300-600 μm diameter) interconnected pores, and sufficient stability to ensure successful surgical transplantation in vivo. Given their successful survival and function in vivo within the porous scaffold, in vitro assembled hLEC networks using this method are potentially applicable to clinical scenarios requiring replacement of dysfunctional or absent lymphatic networks.
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Affiliation(s)
- Anne M Kong
- O’Brien Institute Department of St
Vincent’s Institute of Medical Research, Fitzroy, VIC, Australia
| | - Shiang Y Lim
- O’Brien Institute Department of St
Vincent’s Institute of Medical Research, Fitzroy, VIC, Australia
- Department of Surgery at St Vincent’s
Hospital Melbourne, University of Melbourne, Fitzroy, VIC, Australia
- Drug Discovery Biology, Faculty of
Pharmacy and Pharmaceutical Sciences, Monash University, Parkville, VIC,
Australia
- National Heart Research Institute
Singapore, National Heart Centre Singapore
| | - Jason A Palmer
- O’Brien Institute Department of St
Vincent’s Institute of Medical Research, Fitzroy, VIC, Australia
- Centre for Eye Research Australia, East
Melbourne, VIC, Australia
| | - Amanda Rixon
- Experimental Medical and Surgical Unit,
St Vincent’s Hospital Melbourne, Fitzroy, VIC, Australia
| | - Yi-Wen Gerrand
- O’Brien Institute Department of St
Vincent’s Institute of Medical Research, Fitzroy, VIC, Australia
| | - Kiryu K Yap
- O’Brien Institute Department of St
Vincent’s Institute of Medical Research, Fitzroy, VIC, Australia
- Department of Surgery at St Vincent’s
Hospital Melbourne, University of Melbourne, Fitzroy, VIC, Australia
| | - Wayne A Morrison
- O’Brien Institute Department of St
Vincent’s Institute of Medical Research, Fitzroy, VIC, Australia
- Department of Surgery at St Vincent’s
Hospital Melbourne, University of Melbourne, Fitzroy, VIC, Australia
- Faculty of Health Sciences, Australian
Catholic University, East Melbourne VIC, Australia
- Department of Plastic and
Reconstructive Surgery, St Vincent’s Hospital Melbourne, Fitzroy, VIC,
Australia
| | - Geraldine M Mitchell
- O’Brien Institute Department of St
Vincent’s Institute of Medical Research, Fitzroy, VIC, Australia
- Department of Surgery at St Vincent’s
Hospital Melbourne, University of Melbourne, Fitzroy, VIC, Australia
- Faculty of Health Sciences, Australian
Catholic University, East Melbourne VIC, Australia
- Geraldine M Mitchell, O’Brien Institute
Department at St Vincent’s Institute of Medical Research, 9 Princes Street,
Fitzroy, VIC 3065, Australia.
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Yap KK, Gerrand YW, Dingle AM, Yeoh GC, Morrison WA, Mitchell GM. Liver sinusoidal endothelial cells promote the differentiation and survival of mouse vascularised hepatobiliary organoids. Biomaterials 2020; 251:120091. [PMID: 32408048 DOI: 10.1016/j.biomaterials.2020.120091] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 04/15/2020] [Accepted: 05/02/2020] [Indexed: 02/08/2023]
Abstract
The structural and physiological complexity of currently available liver organoids is limited, thereby reducing their relevance for drug studies, disease modelling, and regenerative therapy. In this study we combined mouse liver progenitor cells (LPCs) with mouse liver sinusoidal endothelial cells (LSECs) to generate hepatobiliary organoids with liver-specific vasculature. Organoids consisting of 5x103 cells were created from either LPCs, or a 1:1 combination of LPC/LSECs. LPC organoids demonstrated mild hepatobiliary differentiation in vitro with minimal morphological change; in contrast LPC/LSEC organoids developed clusters of polygonal hepatocyte-like cells and biliary ducts over a 7 day period. Hepatic (albumin, CPS1, CYP3A11) and biliary (GGT1) genes were significantly upregulated in LPC/LSEC organoids compared to LPC organoids over 7 days, as was albumin secretion. LPC/LSEC organoids also had significantly higher in vitro viability compared to LPC organoids. LPC and LPC/LSEC organoids were transplanted into vascularised chambers created in Fah-/-/Rag2-/-/Il2rg-/- mice (50 LPC organoids, containing 2.5x105 LPCs, and 100 LPC/LSEC organoids, containing 2.5x105 LPCs). At 2 weeks, minimal LPCs survived in chambers with LPC organoids, but robust hepatobiliary ductular tissue was present in LPC/LSEC organoids. Morphometric analysis demonstrated a 115-fold increase in HNF4α+ cells in LPC/LSEC organoid chambers (17.26 ± 4.34 cells/mm2 vs 0.15 ± 0.15 cells/mm2, p = 0.018), and 42-fold increase in Sox9+ cells in LPC/LSEC organoid chambers (28.29 ± 6.05 cells/mm2 vs 0.67 ± 0.67 cells/mm2, p = 0.011). This study presents a novel method to develop vascularised hepatobiliary organoids, with both in vitro and in vivo results confirming that incorporating LSECs with LPCs into organoids significantly increases the differentiation of hepatobiliary tissue within organoids and their survival post-transplantation.
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Affiliation(s)
- Kiryu K Yap
- O'Brien Institute, Department of St Vincent's Institute, Victoria, Australia; University of Melbourne Department of Surgery, St Vincent's Hospital Melbourne, Victoria, Australia.
| | - Yi-Wen Gerrand
- O'Brien Institute, Department of St Vincent's Institute, Victoria, Australia
| | - Aaron M Dingle
- O'Brien Institute, Department of St Vincent's Institute, Victoria, Australia
| | - George C Yeoh
- Harry Perkins Institute of Medical Research & Centre for Medical Research, University of Western Australia, Western Australia, Australia
| | - Wayne A Morrison
- O'Brien Institute, Department of St Vincent's Institute, Victoria, Australia; University of Melbourne Department of Surgery, St Vincent's Hospital Melbourne, Victoria, Australia; Australian Catholic University, Victoria, Australia
| | - Geraldine M Mitchell
- O'Brien Institute, Department of St Vincent's Institute, Victoria, Australia; University of Melbourne Department of Surgery, St Vincent's Hospital Melbourne, Victoria, Australia; Australian Catholic University, Victoria, Australia
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Rnjak‐Kovacina J, Gerrand Y, Wray LS, Tan B, Joukhdar H, Kaplan DL, Morrison WA, Mitchell GM. Vascular Pedicle and Microchannels: Simple Methods Toward Effective In Vivo Vascularization of 3D Scaffolds. Adv Healthc Mater 2019; 8:e1901106. [PMID: 31714024 DOI: 10.1002/adhm.201901106] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 10/03/2019] [Indexed: 12/28/2022]
Abstract
Poor vascularization remains a key limiting factor in translating advances in tissue engineering to clinical applications. Vascular pedicles (large arteries and veins) isolated in plastic chambers are known to sprout an extensive capillary network. This study examined the effect vascular pedicles and scaffold architecture have on vascularization and tissue integration of implanted silk scaffolds. Porous silk scaffolds with or without microchannels are manufactured to support implantation of a central vascular pedicle, without a chamber, implanted in the groin of Sprague Dawley rats, and assessed morphologically and morphometrically at 2 and 6 weeks. At both time points, blood vessels, connective tissue, and an inflammatory response infiltrate all scaffold pores externally, and centrally when a vascular pedicle is implanted. At week 2, vascular pedicles significantly increase the degree of scaffold tissue infiltration, and both the pedicle and the scaffold microchannels significantly increase vascular volume and vascular density. Interestingly, microchannels contribute to increased scaffold vascularity without affecting overall tissue infiltration, suggesting a direct effect of biomaterial architecture on vascularization. The inclusion of pedicles and microchannels are simple and effective proangiogenic techniques for engineering thick tissue constructs as both increase the speed of construct vascularization in the early weeks post in vivo implantation.
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Affiliation(s)
- Jelena Rnjak‐Kovacina
- Department of Biomedical EngineeringTufts University Medford MA 02155 USA
- Graduate School of Biomedical EngineeringUniversity of New South Wales Sydney NSW 2052 Australia
| | - Yi‐wen Gerrand
- O'Brien Institute DepartmentSt Vincent's Institute for Medical Research Melbourne VIC 3065 Australia
| | - Lindsay S. Wray
- Department of Biomedical EngineeringTufts University Medford MA 02155 USA
| | - Beryl Tan
- O'Brien Institute DepartmentSt Vincent's Institute for Medical Research Melbourne VIC 3065 Australia
| | - Habib Joukhdar
- Graduate School of Biomedical EngineeringUniversity of New South Wales Sydney NSW 2052 Australia
| | - David L. Kaplan
- Department of Biomedical EngineeringTufts University Medford MA 02155 USA
| | - Wayne A. Morrison
- O'Brien Institute DepartmentSt Vincent's Institute for Medical Research Melbourne VIC 3065 Australia
- Department of Surgery at St Vincent's HospitalUniversity of Melbourne Melbourne VIC 3065 Australia
- Health Sciences FacultyAustralian Catholic University Melbourne VIC 3065 Australia
| | - Geraldine M. Mitchell
- O'Brien Institute DepartmentSt Vincent's Institute for Medical Research Melbourne VIC 3065 Australia
- Department of Surgery at St Vincent's HospitalUniversity of Melbourne Melbourne VIC 3065 Australia
- Health Sciences FacultyAustralian Catholic University Melbourne VIC 3065 Australia
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Kong AM, Yap KK, Lim SY, Marre D, Pébay A, Gerrand YW, Lees JG, Palmer JA, Morrison WA, Mitchell GM. Bio-engineering a tissue flap utilizing a porous scaffold incorporating a human induced pluripotent stem cell-derived endothelial cell capillary network connected to a vascular pedicle. Acta Biomater 2019; 94:281-294. [PMID: 31152943 DOI: 10.1016/j.actbio.2019.05.067] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 05/21/2019] [Accepted: 05/28/2019] [Indexed: 01/18/2023]
Abstract
Tissue flaps are used to cover large/poorly healing wounds, but involve complex surgery and donor site morbidity. In this study a tissue flap is assembled using the mammalian body as a bioreactor to functionally connect an artery and vein to a human capillary network assembled from induced pluripotent stem cell-derived endothelial cells (hiPSC ECs). In vitro: Porous NovoSorb™ scaffolds (3 mm × 1.35 mm) were seeded with 200,000 hiPSC ECs ± 100,000 human vascular smooth muscle cells (hvSMC), and cultured for 1-3 days, with capillaries formed by 24 h which were CD31+, VE-Cadherin+, EphB4+, VEGFR2+ and Ki67+, whilst hvSMCs (calponin+) attached abluminally. In vivo: In SCID mice, bi-lateral epigastric vascular pedicles were isolated in a silicone chamber for a 3 week 'delay period' for pedicle capillary sprouting, then reopened, and two hiPSC EC ± hvSMCs seeded scaffolds transplanted over the pedicle. The chamber was either resealed (Group 1), or removed and surrounding tissue secured around the pedicle + scaffolds (Group 2), for 1 or 2 weeks. Human capillaries survived in vivo and were CD31+, VE-Cadherin+ and VEGFR2+. Human vSMCs remained attached, and host mesenchymal cells also attached abluminally. Systemically injected FITC-dextran present in human capillary lumens indicated inosculation to host capillaries. Human iPSC EC capillary morphometric parameters at one week in vivo were equal to or higher than the same parameters measured in human abdominal skin. This 'proof of concept' study has demonstrated that bio-engineering an autologous human tissue flap based on hiPSC EC could minimize the use of donor flaps and has potential applications for complex wound coverage. STATEMENT OF SIGNIFICANCE: Tissue flaps, used for surgical reconstruction of wounds, require complex surgery, often associated with morbidity. Bio-engineering a simpler alternative, we assembled a human induced pluripotent stem cell derived endothelial cell (hiPSC ECs) capillary network in a porous scaffold in vitro, which when transplanted over a mouse vascular pedicle in vivo formed a functional tissue flap with mouse blood flow in the human capillaries. Therefore it is feasible to form an autologous tissue flap derived from a hiPSC EC capillary network assembled in vitro, and functionally connect to a vascular pedicle in vivo that could be utilized in complex wound repair for chronic or acute wounds.
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Affiliation(s)
- Anne M Kong
- O'Brien Institute Dept. of St Vincent's Institute, Melbourne, Australia
| | - Kiryu K Yap
- O'Brien Institute Dept. of St Vincent's Institute, Melbourne, Australia; Univ. of Melbourne, Dept. of Surgery at St Vincent's Hospital, Melbourne, Australia; Department of Plastic and Reconstructive Surgery, St Vincent's Hospital, Melbourne, Australia
| | - Shiang Y Lim
- O'Brien Institute Dept. of St Vincent's Institute, Melbourne, Australia; Univ. of Melbourne, Dept. of Surgery at St Vincent's Hospital, Melbourne, Australia
| | - Diego Marre
- O'Brien Institute Dept. of St Vincent's Institute, Melbourne, Australia
| | - Alice Pébay
- Department of Surgery, The University of Melbourne, Melbourne, Victoria 3010, Australia; Department of Anatomy and Neuroscience, The University of Melbourne, Victoria 3010, Australia
| | - Yi-Wen Gerrand
- O'Brien Institute Dept. of St Vincent's Institute, Melbourne, Australia
| | - Jarmon G Lees
- O'Brien Institute Dept. of St Vincent's Institute, Melbourne, Australia
| | - Jason A Palmer
- O'Brien Institute Dept. of St Vincent's Institute, Melbourne, Australia
| | - Wayne A Morrison
- O'Brien Institute Dept. of St Vincent's Institute, Melbourne, Australia; Univ. of Melbourne, Dept. of Surgery at St Vincent's Hospital, Melbourne, Australia; Faculty of Health Sciences, Australian Catholic University, Fitzroy, Melbourne, Australia; Department of Plastic and Reconstructive Surgery, St Vincent's Hospital, Melbourne, Australia
| | - Geraldine M Mitchell
- O'Brien Institute Dept. of St Vincent's Institute, Melbourne, Australia; Univ. of Melbourne, Dept. of Surgery at St Vincent's Hospital, Melbourne, Australia; Faculty of Health Sciences, Australian Catholic University, Fitzroy, Melbourne, Australia.
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Abstract
The success of tissue engineering hinges on the rapid and sufficient vascularization of the neotissue. For efficient vascular network formation within three-dimensional (3D) constructs, biomaterial scaffolds that can support survival of endothelial cells as well as formation and maturation of a capillary network in vivo are highly sought after. Here, we outline a method to biofabricate 3D porous collagen scaffolds that can support extrinsic and intrinsic vascularization using two different in vivo animal models-the mouse subcutaneous implant model (extrinsic vascularization, capillary growth within the scaffold originating from host tissues outside the scaffold) and the rat tissue engineering chamber model (intrinsic vascularization, capillary growth within the scaffold derived from a centrally positioned vascular pedicle). These in vivo vascular tissue engineering approaches hold a great promise for the generation of clinically viable vascularized constructs. Moreover, the 3D collagen scaffolds can also be employed for 3D cell culture and for in vivo delivery of growth factors and cells.
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Affiliation(s)
- Jiang-Hui Wang
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, VIC, Australia
- Department of Medicine, Surgery and Ophthalmology, University of Melbourne, East Melbourne, VIC, Australia
| | - Jinying Chen
- Department of Ophthalmology, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong, China
| | - Shyh-Ming Kuo
- Department of Biomedical Engineering, I-Shou University, Kaohsiung, Taiwan
| | - Geraldine M Mitchell
- Department of Medicine, Surgery and Ophthalmology, University of Melbourne, East Melbourne, VIC, Australia
- O'Brien Institute Department, St Vincent's Institute of Medical Research, Fitzroy, VIC, Australia
- Faculty of Health Sciences, Australian Catholic University, Melbourne, VIC, Australia
| | - Shiang Y Lim
- Department of Medicine, Surgery and Ophthalmology, University of Melbourne, East Melbourne, VIC, Australia
- O'Brien Institute Department, St Vincent's Institute of Medical Research, Fitzroy, VIC, Australia
| | - Guei-Sheung Liu
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, VIC, Australia
- Department of Medicine, Surgery and Ophthalmology, University of Melbourne, East Melbourne, VIC, Australia
- Department of Ophthalmology, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong, China
- Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS, Australia
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Williams MD, Joglekar MV, Satoor SN, Wong W, Keramidaris E, Rixon A, O'Connell P, Hawthorne WJ, Mitchell GM, Hardikar AA. Epigenetic and Transcriptome Profiling Identifies a Population of Visceral Adipose-Derived Progenitor Cells with the Potential to Differentiate into an Endocrine Pancreatic Lineage. Cell Transplant 2018; 28:89-104. [PMID: 30376726 PMCID: PMC6322142 DOI: 10.1177/0963689718808472] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Type 1 diabetes (T1D) is characterized by the loss of insulin-producing β-cells in the pancreas. T1D can be treated using cadaveric islet transplantation, but this therapy is severely limited by a lack of pancreas donors. To develop an alternative cell source for transplantation therapy, we carried out the epigenetic characterization in nine different adult mouse tissues and identified visceral adipose-derived progenitors as a candidate cell population. Chromatin conformation, assessed using chromatin immunoprecipitation (ChIP) sequencing and validated by ChIP-polymerase chain reaction (PCR) at key endocrine pancreatic gene promoters, revealed similarities between visceral fat and endocrine pancreas. Multiple techniques involving quantitative PCR, in-situ PCR, confocal microscopy, and flow cytometry confirmed the presence of measurable (2-1000-fold over detectable limits) pancreatic gene transcripts and mesenchymal progenitor cell markers (CD73, CD90 and CD105; >98%) in visceral adipose tissue-derived mesenchymal cells (AMCs). The differentiation potential of AMCs was explored in transgenic reporter mice expressing green fluorescent protein (GFP) under the regulation of the Pdx1 (pancreatic and duodenal homeobox-1) gene promoter. GFP expression was measured as an index of Pdx1 promoter activity to optimize culture conditions for endocrine pancreatic differentiation. Differentiated AMCs demonstrated their capacity to induce pancreatic endocrine genes as evidenced by increased GFP expression and validated using TaqMan real-time PCR (at least 2-200-fold relative to undifferentiated AMCs). Human AMCs differentiated using optimized protocols continued to produce insulin following transplantation in NOD/SCID mice. Our studies provide a systematic analysis of potential islet progenitor populations using genome-wide profiling studies and characterize visceral adipose-derived cells for replacement therapy in diabetes.
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Affiliation(s)
- Michael D Williams
- 1 NHMRC Clinical Trials Centre, University of Sydney, Camperdown, New South Wales, Australia.,2 Department of Surgery, St Vincent's Hospital, University of Melbourne, Fitzroy, Victoria, Australia.,3 O'Brien Institute Department, St. Vincent's Institute of Medical Research, Fitzroy, Victoria, Australia
| | - Mugdha V Joglekar
- 1 NHMRC Clinical Trials Centre, University of Sydney, Camperdown, New South Wales, Australia
| | - Sarang N Satoor
- 1 NHMRC Clinical Trials Centre, University of Sydney, Camperdown, New South Wales, Australia
| | - Wilson Wong
- 1 NHMRC Clinical Trials Centre, University of Sydney, Camperdown, New South Wales, Australia
| | - Effie Keramidaris
- 3 O'Brien Institute Department, St. Vincent's Institute of Medical Research, Fitzroy, Victoria, Australia
| | - Amanda Rixon
- 3 O'Brien Institute Department, St. Vincent's Institute of Medical Research, Fitzroy, Victoria, Australia.,4 Experimental Medical and Surgical Unit (EMSU), St Vincent's Hospital, Fitzroy, Victoria, Australia
| | - Philip O'Connell
- 5 The Center for Transplant and Renal Research, Westmead Institute of Medical Research, The University of Sydney, Westmead, New South Wales, Australia
| | - Wayne J Hawthorne
- 5 The Center for Transplant and Renal Research, Westmead Institute of Medical Research, The University of Sydney, Westmead, New South Wales, Australia
| | - Geraldine M Mitchell
- 2 Department of Surgery, St Vincent's Hospital, University of Melbourne, Fitzroy, Victoria, Australia.,3 O'Brien Institute Department, St. Vincent's Institute of Medical Research, Fitzroy, Victoria, Australia.,6 Faculty of Health Sciences, Australian Catholic University, Fitzroy, Victoria, Australia
| | - Anandwardhan A Hardikar
- 1 NHMRC Clinical Trials Centre, University of Sydney, Camperdown, New South Wales, Australia
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9
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Yap KK, Yeoh GC, Morrison WA, Mitchell GM. The Vascularised Chamber as an In Vivo Bioreactor. Trends Biotechnol 2018; 36:1011-1024. [DOI: 10.1016/j.tibtech.2018.05.009] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2018] [Revised: 05/25/2018] [Accepted: 05/29/2018] [Indexed: 02/06/2023]
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10
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Dingle AM, Yap KK, Gerrand YW, Taylor CJ, Keramidaris E, Lokmic Z, Kong AM, Peters HL, Morrison WA, Mitchell GM. Characterization of isolated liver sinusoidal endothelial cells for liver bioengineering. Angiogenesis 2018; 21:581-597. [PMID: 29582235 DOI: 10.1007/s10456-018-9610-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Accepted: 03/14/2018] [Indexed: 01/09/2023]
Abstract
BACKGROUND The liver sinusoidal capillaries play a pivotal role in liver regeneration, suggesting they may be beneficial in liver bioengineering. This study isolated mouse liver sinusoidal endothelial cells (LSECs) and determined their ability to form capillary networks in vitro and in vivo for liver tissue engineering purposes. METHODS AND RESULTS In vitro LSECs were isolated from adult C57BL/6 mouse livers. Immunofluorescence labelling indicated they were LYVE-1+/CD32b+/FactorVIII+/CD31-. Scanning electron microscopy of LSECs revealed the presence of characteristic sieve plates at 2 days. LSECs formed tubes and sprouts in the tubulogenesis assay, similar to human microvascular endothelial cells (HMEC); and formed capillaries with lumens when implanted in a porous collagen scaffold in vitro. LSECs were able to form spheroids, and in the spheroid gel sandwich assay produced significantly increased numbers (p = 0.0011) of capillary-like sprouts at 24 h compared to HMEC spheroids. Supernatant from LSEC spheroids demonstrated significantly greater levels of vascular endothelial growth factor-A and C (VEGF-A, VEGF-C) and hepatocyte growth factor (HGF) compared to LSEC monolayers (p = 0.0167; p = 0.0017; and p < 0.0001, respectively), at 2 days, which was maintained to 4 days for HGF (p = 0.0017) and VEGF-A (p = 0.0051). In vivo isolated mouse LSECs were prepared as single cell suspensions of 500,000 cells, or as spheroids of 5000 cells (100 spheroids) and implanted in SCID mouse bilateral vascularized tissue engineering chambers for 2 weeks. Immunohistochemistry identified implanted LSECs forming LYVE-1+/CD31- vessels. In LSEC implanted constructs, overall lymphatic vessel growth was increased (not significantly), whilst host-derived CD31+ blood vessel growth increased significantly (p = 0.0127) compared to non-implanted controls. LSEC labelled with the fluorescent tag DiI prior to implantation formed capillaries in vivo and maintained LYVE-1 and CD32b markers to 2 weeks. CONCLUSION Isolated mouse LSECs express a panel of vascular-related cell markers and demonstrate substantial vascular capillary-forming ability in vitro and in vivo. Their production of liver growth factors VEGF-A, VEGF-C and HGF enable these cells to exert a growth stimulus post-transplantation on the in vivo host-derived capillary bed, reinforcing their pro-regenerative capabilities for liver tissue engineering studies.
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Affiliation(s)
- A M Dingle
- O'Brien Institute Department, St Vincent's Institute of Medical Research, Melbourne, Australia.,Department of Surgery, St Vincent's Hospital, University of Melbourne, Melbourne, Australia
| | - K K Yap
- O'Brien Institute Department, St Vincent's Institute of Medical Research, Melbourne, Australia.,Department of Surgery, St Vincent's Hospital, University of Melbourne, Melbourne, Australia
| | - Y-W Gerrand
- O'Brien Institute Department, St Vincent's Institute of Medical Research, Melbourne, Australia.,Faculty of Health Sciences, Australian Catholic University, Melbourne, Australia
| | - C J Taylor
- O'Brien Institute Department, St Vincent's Institute of Medical Research, Melbourne, Australia.,Department of Surgery, St Vincent's Hospital, University of Melbourne, Melbourne, Australia.,Faculty of Health Sciences, Australian Catholic University, Melbourne, Australia
| | - E Keramidaris
- O'Brien Institute Department, St Vincent's Institute of Medical Research, Melbourne, Australia
| | - Z Lokmic
- Division of Cancer Research, Peter MacCallum Cancer Centre, Melbourne, Australia.,Department of Paediatrics and Nursing, University of Melbourne, Melbourne, Australia
| | - A M Kong
- O'Brien Institute Department, St Vincent's Institute of Medical Research, Melbourne, Australia
| | - H L Peters
- Department of Paediatrics and Nursing, University of Melbourne, Melbourne, Australia.,Royal Children's Hospital, Melbourne, Australia
| | - W A Morrison
- O'Brien Institute Department, St Vincent's Institute of Medical Research, Melbourne, Australia.,Department of Surgery, St Vincent's Hospital, University of Melbourne, Melbourne, Australia.,Faculty of Health Sciences, Australian Catholic University, Melbourne, Australia
| | - G M Mitchell
- O'Brien Institute Department, St Vincent's Institute of Medical Research, Melbourne, Australia. .,Department of Surgery, St Vincent's Hospital, University of Melbourne, Melbourne, Australia. .,Faculty of Health Sciences, Australian Catholic University, Melbourne, Australia.
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11
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Tan SS, Zhan W, Poon CJ, Han X, Marre D, Boodhun S, Palmer JA, Mitchell GM, Morrison WA. Melatonin promotes survival of nonvascularized fat grafts and enhances the viability and migration of human adipose‐derived stem cells via down‐regulation of acute inflammatory cytokines. J Tissue Eng Regen Med 2017; 12:382-392. [DOI: 10.1002/term.2463] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Revised: 04/01/2017] [Accepted: 05/04/2017] [Indexed: 01/20/2023]
Affiliation(s)
- Shaun S. Tan
- Bernard O’Brien Institute DepartmentSt Vincent' Institute of Medical Research Melbourne Australia
- University of MelbourneDepartment of Surgery at St Vincent' Hospital Melbourne Australia
| | - Weiqing Zhan
- Bernard O’Brien Institute DepartmentSt Vincent' Institute of Medical Research Melbourne Australia
| | - Christopher J. Poon
- Bernard O’Brien Institute DepartmentSt Vincent' Institute of Medical Research Melbourne Australia
| | - Xiaolian Han
- Bernard O’Brien Institute DepartmentSt Vincent' Institute of Medical Research Melbourne Australia
| | - Diego Marre
- Bernard O’Brien Institute DepartmentSt Vincent' Institute of Medical Research Melbourne Australia
| | - Sholeh Boodhun
- Bernard O’Brien Institute DepartmentSt Vincent' Institute of Medical Research Melbourne Australia
| | - Jason A. Palmer
- Bernard O’Brien Institute DepartmentSt Vincent' Institute of Medical Research Melbourne Australia
| | - Geraldine M. Mitchell
- Bernard O’Brien Institute DepartmentSt Vincent' Institute of Medical Research Melbourne Australia
- University of MelbourneDepartment of Surgery at St Vincent' Hospital Melbourne Australia
- Faculty of Health SciencesAustralian Catholic University Fitzroy Melbourne Australia
| | - Wayne A. Morrison
- Bernard O’Brien Institute DepartmentSt Vincent' Institute of Medical Research Melbourne Australia
- University of MelbourneDepartment of Surgery at St Vincent' Hospital Melbourne Australia
- Faculty of Health SciencesAustralian Catholic University Fitzroy Melbourne Australia
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12
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Taylor CJ, Church JE, Williams MD, Gerrand YW, Keramidaris E, Palmer JA, Galea LA, Penington AJ, Morrison WA, Mitchell GM. Hypoxic preconditioning of myoblasts implanted in a tissue engineering chamber significantly increases local angiogenesis via upregulation of myoblast vascular endothelial growth factor-A expression and downregulation of miRNA-1, miRNA-206 and angiopoietin-1. J Tissue Eng Regen Med 2017; 12:e408-e421. [PMID: 28477583 DOI: 10.1002/term.2440] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Revised: 02/01/2017] [Accepted: 05/03/2017] [Indexed: 12/14/2022]
Abstract
Vascularization is a major hurdle for growing three-dimensional tissue engineered constructs. This study investigated the mechanisms involved in hypoxic preconditioning of primary rat myoblasts in vitro and their influence on local angiogenesis postimplantation. Primary rat myoblast cultures were exposed to 90 min hypoxia at <1% oxygen followed by normoxia for 24 h. Real time (RT) polymerase chain reaction evaluation indicated that 90 min hypoxia resulted in significant downregulation of miR-1 and miR-206 (p < 0.05) and angiopoietin-1 (p < 0.05) with upregulation of vascular endothelial growth factor-A (VEGF-A; p < 0.05). The miR-1 and angiopoietin-1 responses remained significantly downregulated after a 24 h rest phase. In addition, direct inhibition of miR-206 in L6 myoblasts caused a significant increase in VEGF-A expression (p < 0.05), further establishing that changes in VEGF-A expression are influenced by miR-206. Of the myogenic genes examined, MyoD was significantly upregulated, only after 24 h rest (p < 0.05). Preconditioned or control myoblasts were implanted with Matrigel™ into isolated bilateral tissue engineering chambers incorporating a flow-through epigastric vascular pedicle in severe combined immunodeficiency mice and the chamber tissue harvested 14 days later. Chambers implanted with preconditioned myoblasts had a significantly increased percentage volume of blood vessels (p = 0.0325) compared with chambers implanted with control myoblasts. Hypoxic preconditioned myoblasts promote vascularization of constructs via VEGF upregulation and downregulation of angiopoietin-1, miR-1 and miR-206. The relatively simple strategy of hypoxic preconditioning of implanted cells - including non-stem cell types - has broad, future applications in tissue engineering of skeletal muscle and other tissues, as a technique to significantly increase implant site angiogenesis.
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Affiliation(s)
- C J Taylor
- O'Brien Institute Department, St Vincent's Institute, Melbourne, Australia.,Department of Surgery, St Vincent's Hospital, University of Melbourne, Melbourne, Australia.,Faculty of Health Sciences, Australian Catholic University, Melbourne, Australia.,Department of Physiology, Anatomy & Microbiology, La Trobe University, Bundoora, Victoria, Australia
| | - J E Church
- Department of Physiology, Anatomy & Microbiology, La Trobe University, Bundoora, Victoria, Australia
| | - M D Williams
- O'Brien Institute Department, St Vincent's Institute, Melbourne, Australia.,Department of Surgery, St Vincent's Hospital, University of Melbourne, Melbourne, Australia
| | - Y-W Gerrand
- O'Brien Institute Department, St Vincent's Institute, Melbourne, Australia.,Faculty of Health Sciences, Australian Catholic University, Melbourne, Australia
| | - E Keramidaris
- O'Brien Institute Department, St Vincent's Institute, Melbourne, Australia
| | - J A Palmer
- O'Brien Institute Department, St Vincent's Institute, Melbourne, Australia.,Faculty of Health Sciences, Australian Catholic University, Melbourne, Australia
| | - L A Galea
- O'Brien Institute Department, St Vincent's Institute, Melbourne, Australia
| | - A J Penington
- Pediatric Plastic and Maxillofacial Surgery, Royal Children's Hospital, Parkville, Victoria, Australia
| | - W A Morrison
- O'Brien Institute Department, St Vincent's Institute, Melbourne, Australia.,Department of Surgery, St Vincent's Hospital, University of Melbourne, Melbourne, Australia.,Faculty of Health Sciences, Australian Catholic University, Melbourne, Australia
| | - G M Mitchell
- O'Brien Institute Department, St Vincent's Institute, Melbourne, Australia.,Department of Surgery, St Vincent's Hospital, University of Melbourne, Melbourne, Australia.,Faculty of Health Sciences, Australian Catholic University, Melbourne, Australia
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13
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Debels H, Gerrand YW, Poon CJ, Abberton KM, Morrison WA, Mitchell GM. An adipogenic gel for surgical reconstruction of the subcutaneous fat layer in a rat model. J Tissue Eng Regen Med 2017; 11:1230-1241. [PMID: 25950280 DOI: 10.1002/term.2025] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Revised: 12/16/2014] [Accepted: 02/26/2015] [Indexed: 01/02/2023]
Abstract
'Off-the-shelf' tissue-engineered skin alternatives for epidermal and dermal skin layers are available; however, no such alternative for the subdermal fat layer exists. Without this well-vascularized layer, skin graft take is variable and grafts may have reduced mobility, contracture and contour defects. In this study a novel adipose-derived acellular matrix (Adipogel) was investigated for its properties to generate subdermal fat in a rat model. In a dorsal thoracic site, a 1 × 1 cm Adipogel implant was inserted within a subdermal fat layer defect. In a dorsal lumbar site, an Adipogel implant was inserted in a subfascial pocket. Contralateral control defects remained empty. At 8 weeks wound/implant sites were evaluated histologically, immunohistochemically and morphometrically. Identifiable thoracic Adipogel implants lost volume in vivo over 8 weeks. Neovascularization and adipogenesis were evident within implants and adipocyte percentage volume was 33.07 ± 6.55% (mean ± SEM). A comparison of entire cross-sections of thoracic wounds demonstrated a significant increase in total wound fat in Adipogel-implanted wounds (37.19 ± 4.48%, mean ± SEM) compared to control (16.53 ± 4.60%; p = 0.0092), indicating that some Adipogel had been completely converted to normal fat. At the lumbar site, Adipogel also lost volume, appearing flattened, although fat generation and angiogenesis occurred. At both sites macrophage infiltration was mild, whilst many infiltrating cells were PDGFRβ-positive mesenchymal cells. Adipogel is adipogenic and angiogenic and is a promising candidate for subcutaneous fat regeneration; it has the potential to be a valuable adjunct to wound-healing therapy and reconstructive surgery practice. Copyright © 2015 John Wiley & Sons, Ltd.
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Affiliation(s)
- Heidi Debels
- O'Brien Institute, Fitzroy, Victoria, Australia
- Department of Plastic and Reconstructive Surgery, Free University of Brussels (VUB), Belgium
| | - Yi-Wen Gerrand
- O'Brien Institute, Fitzroy, Victoria, Australia
- Health Science Faculty, Australian Catholic University, Fitzroy, Australia
| | | | - Keren M Abberton
- O'Brien Institute, Fitzroy, Victoria, Australia
- Health Science Faculty, Australian Catholic University, Fitzroy, Australia
- Department of Surgery, University of Melbourne, St. Vincent's Hospital, Melbourne, Australia
| | - Wayne A Morrison
- O'Brien Institute, Fitzroy, Victoria, Australia
- Health Science Faculty, Australian Catholic University, Fitzroy, Australia
- Department of Surgery, University of Melbourne, St. Vincent's Hospital, Melbourne, Australia
| | - Geraldine M Mitchell
- O'Brien Institute, Fitzroy, Victoria, Australia
- Health Science Faculty, Australian Catholic University, Fitzroy, Australia
- Department of Surgery, University of Melbourne, St. Vincent's Hospital, Melbourne, Australia
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14
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Affiliation(s)
- A P M Forrest
- Welsh National School of Medicine, and United Cardiff Hospitals, Cardiff; Imperial Cancer Fund Research Laboratories, London
| | - F C Greenwood
- Welsh National School of Medicine, and United Cardiff Hospitals, Cardiff; Imperial Cancer Fund Research Laboratories, London
| | - H J Stewart
- Welsh National School of Medicine, and United Cardiff Hospitals, Cardiff; Imperial Cancer Fund Research Laboratories, London
| | - J P Thomas
- Welsh National School of Medicine, and United Cardiff Hospitals, Cardiff; Imperial Cancer Fund Research Laboratories, London
| | - R G Wood
- Welsh National School of Medicine, and United Cardiff Hospitals, Cardiff; Imperial Cancer Fund Research Laboratories, London
| | - W R G Thomas
- Welsh National School of Medicine, and United Cardiff Hospitals, Cardiff; Imperial Cancer Fund Research Laboratories, London
| | - A S Bligh
- Welsh National School of Medicine, and United Cardiff Hospitals, Cardiff; Imperial Cancer Fund Research Laboratories, London
| | - G M Mitchell
- Welsh National School of Medicine, and United Cardiff Hospitals, Cardiff; Imperial Cancer Fund Research Laboratories, London
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15
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Affiliation(s)
- G M Mitchell
- Department of Materia Medica and Pharmacology, Welsh National School of Medicine, Cardiff
| | - K Dierst-Davies
- Department of Materia Medica and Pharmacology, Welsh National School of Medicine, Cardiff
| | - F W Landgrebe
- Department of Materia Medica and Pharmacology, Welsh National School of Medicine, Cardiff
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16
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Zhan W, Marre D, Mitchell GM, Morrison WA, Lim SY. Tissue Engineering by Intrinsic Vascularization in an In Vivo Tissue Engineering Chamber. J Vis Exp 2016. [PMID: 27286267 DOI: 10.3791/54099] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
In reconstructive surgery, there is a clinical need for an alternative to the current methods of autologous reconstruction which are complex, costly and trade one defect for another. Tissue engineering holds the promise to address this increasing demand. However, most tissue engineering strategies fail to generate stable and functional tissue substitutes because of poor vascularization. This paper focuses on an in vivo tissue engineering chamber model of intrinsic vascularization where a perfused artery and a vein either as an arteriovenous loop or a flow-through pedicle configuration is directed inside a protected hollow chamber. In this chamber-based system angiogenic sprouting occurs from the arteriovenous vessels and this system attracts ischemic and inflammatory driven endogenous cell migration which gradually fills the chamber space with fibro-vascular tissue. Exogenous cell/matrix implantation at the time of chamber construction enhances cell survival and determines specificity of the engineered tissues which develop. Our studies have shown that this chamber model can successfully generate different tissues such as fat, cardiac muscle, liver and others. However, modifications and refinements are required to ensure target tissue formation is consistent and reproducible. This article describes a standardized protocol for the fabrication of two different vascularized tissue engineering chamber models in vivo.
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Affiliation(s)
- Weiqing Zhan
- O'Brien Institute Department, St Vincent's Institute of Medical Research
| | - Diego Marre
- O'Brien Institute Department, St Vincent's Institute of Medical Research
| | - Geraldine M Mitchell
- O'Brien Institute Department, St Vincent's Institute of Medical Research; Department of Surgery, University of Melbourne; Faculty of Health Sciences, Australia Catholic University
| | - Wayne A Morrison
- O'Brien Institute Department, St Vincent's Institute of Medical Research; Department of Surgery, University of Melbourne; Faculty of Health Sciences, Australia Catholic University
| | - Shiang Y Lim
- O'Brien Institute Department, St Vincent's Institute of Medical Research; Department of Surgery, University of Melbourne;
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17
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Chan EC, Kuo SM, Kong AM, Morrison WA, Dusting GJ, Mitchell GM, Lim SY, Liu GS. Three Dimensional Collagen Scaffold Promotes Intrinsic Vascularisation for Tissue Engineering Applications. PLoS One 2016; 11:e0149799. [PMID: 26900837 PMCID: PMC4762944 DOI: 10.1371/journal.pone.0149799] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Accepted: 02/04/2016] [Indexed: 12/30/2022] Open
Abstract
Here, we describe a porous 3-dimensional collagen scaffold material that supports capillary formation in vitro, and promotes vascularization when implanted in vivo. Collagen scaffolds were synthesized from type I bovine collagen and have a uniform pore size of 80 μm. In vitro, scaffolds seeded with primary human microvascular endothelial cells suspended in human fibrin gel formed CD31 positive capillary-like structures with clear lumens. In vivo, after subcutaneous implantation in mice, cell-free collagen scaffolds were vascularized by host neovessels, whilst a gradual degradation of the scaffold material occurred over 8 weeks. Collagen scaffolds, impregnated with human fibrinogen gel, were implanted subcutaneously inside a chamber enclosing the femoral vessels in rats. Angiogenic sprouts from the femoral vessels invaded throughout the scaffolds and these degraded completely after 4 weeks. Vascular volume of the resulting constructs was greater than the vascular volume of constructs from chambers implanted with fibrinogen gel alone (42.7±5.0 μL in collagen scaffold vs 22.5±2.3 μL in fibrinogen gel alone; p<0.05, n = 7). In the same model, collagen scaffolds seeded with human adipose-derived stem cells (ASCs) produced greater increases in vascular volume than did cell-free collagen scaffolds (42.9±4.0 μL in collagen scaffold with human ASCs vs 25.7±1.9 μL in collagen scaffold alone; p<0.05, n = 4). In summary, these collagen scaffolds are biocompatible and could be used to grow more robust vascularized tissue engineering grafts with improved the survival of implanted cells. Such scaffolds could also be used as an assay model for studies on angiogenesis, 3-dimensional cell culture, and delivery of growth factors and cells in vivo.
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Affiliation(s)
- Elsa C. Chan
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, Victoria, Australia
- Ophthalmology, Department of Surgery, University of Melbourne, East Melbourne, Victoria, Australia
| | - Shyh-Ming Kuo
- Department of Biomedical Engineering, I-Shou University, Kaohsiung, Taiwan
| | - Anne M. Kong
- O’Brien Institute Department, St Vincent’s Institute of Medical Research, Fitzroy, Victoria, Australia
| | - Wayne A. Morrison
- O’Brien Institute Department, St Vincent’s Institute of Medical Research, Fitzroy, Victoria, Australia
- Department of Surgery, University of Melbourne, St Vincent’s Hospital Melbourne, Fitzroy, Victoria, Australia
- Faculty of Health Sciences, Australian Catholic University, Fitzroy, Victoria, Australia
| | - Gregory J. Dusting
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, Victoria, Australia
- Ophthalmology, Department of Surgery, University of Melbourne, East Melbourne, Victoria, Australia
- O’Brien Institute Department, St Vincent’s Institute of Medical Research, Fitzroy, Victoria, Australia
| | - Geraldine M. Mitchell
- O’Brien Institute Department, St Vincent’s Institute of Medical Research, Fitzroy, Victoria, Australia
- Department of Surgery, University of Melbourne, St Vincent’s Hospital Melbourne, Fitzroy, Victoria, Australia
- Faculty of Health Sciences, Australian Catholic University, Fitzroy, Victoria, Australia
| | - Shiang Y. Lim
- O’Brien Institute Department, St Vincent’s Institute of Medical Research, Fitzroy, Victoria, Australia
- Department of Surgery, University of Melbourne, St Vincent’s Hospital Melbourne, Fitzroy, Victoria, Australia
- * E-mail: (GSL); (SYL)
| | - Guei-Sheung Liu
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, Victoria, Australia
- Ophthalmology, Department of Surgery, University of Melbourne, East Melbourne, Victoria, Australia
- * E-mail: (GSL); (SYL)
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18
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Palmer JA, Abberton KM, Mitchell GM, Morrison WA. Macrophage Phenotype in Response to Implanted Synthetic Scaffolds: An Immunohistochemical Study in the Rat. Cells Tissues Organs 2014; 199:169-83. [DOI: 10.1159/000363693] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/16/2014] [Indexed: 11/19/2022] Open
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19
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Go DP, Palmer JA, Mitchell GM, Gras SL, O'Connor AJ. Porous PLGA microspheres tailored for dual delivery of biomolecules via layer-by-layer assembly. J Biomed Mater Res A 2014; 103:1849-63. [PMID: 25203163 DOI: 10.1002/jbm.a.35319] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Revised: 07/16/2014] [Accepted: 08/15/2014] [Indexed: 01/15/2023]
Abstract
Tissue engineering is a complex and dynamic process that requires varied biomolecular cues to promote optimal tissue growth. Consequently, the development of delivery systems capable of sequestering more than one biomolecule with controllable release profiles is a key step in the advancement of this field. This study develops multilayered polyelectrolyte films incorporating alpha-melanocyte stimulating hormone (α-MSH), an anti-inflammatory molecule, and basic fibroblast growth factor (bFGF). The layers were successfully formed on macroporous poly lactic-co-glycolic acid microspheres produced using a combined inkjet and thermally induced phase separation technique. Release profiles could be varied by altering layer properties including the number of layers and concentrations of layering molecules. α-MSH and bFGF were released in a sustained manner and the bioactivity of α-MSH was shown to be preserved using an activated macrophage cell assay in vitro. The system performance was also tested in vivo subcutaneously in rats. The multilayered microspheres reduced the inflammatory response induced by a carrageenan stimulus 6 weeks after implantation compared to the non-layered microspheres without the anti-inflammatory and growth factors, demonstrating the potential of such multilayered constructs for the controlled delivery of bioactive molecules.
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Affiliation(s)
- Dewi P Go
- Particulate Fluids Processing Centre, Department of Chemical and Biomolecular Engineering, University of Melbourne, Parkville, 3010, Victoria, Australia; Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, 3010, Victoria, Australia
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Lokmic Z, Mitchell GM, Koh Wee Chong N, Bastiaanse J, Gerrand YW, Zeng Y, Williams ED, Penington AJ. Isolation of human lymphatic malformation endothelial cells, their in vitro characterization and in vivo survival in a mouse xenograft model. Angiogenesis 2013; 17:1-15. [PMID: 23884796 DOI: 10.1007/s10456-013-9371-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Accepted: 07/15/2013] [Indexed: 10/26/2022]
Abstract
Human lymphatic vascular malformations (LMs), also known as cystic hygromas or lymphangioma, consist of multiple lymphatic endothelial cell-lined lymph-containing cysts. No animal model of this disease exists. To develop a mouse xenograft model of human LM, CD34(Neg)CD31(Pos) LM lymphatic endothelial cells (LM-LEC) were isolated from surgical specimens and compared to foreskin CD34(Neg)CD31(Pos) lymphatic endothelial cells (LECs). Cells were implanted into a mouse tissue engineering model for 1, 2 and 4 weeks. In vitro LM-LECs showed increased proliferation and survival under starvation conditions (P < 0.0005 at 48 h, two-way ANOVA), increased migration (P < 0.001, two-way ANOVA) and formed fewer (P = 0.029, independent samples t test), shorter tubes (P = 0.029, independent samples t test) than foreskin LECs. In vivo LM-LECs implanted into a Matrigel™-containing mouse chamber model assembled to develop vessels with dilated cystic lumens lined with flat endothelium, morphology similar to that of clinical LMs. Human foreskin LECs failed to survive implantation. In LM-LEC implanted chambers the percent volume of podoplanin(Pos) vessels was 1.18 ± 2.24 % at 1 week, 6.34 ± 2.68 % at 2 weeks and increasing to 7.67 ± 3.60 % at 4 weeks. In conclusion, the significantly increased proliferation, migration, resistance to apoptosis and decreased tubulogenesis of LM-LECs observed in vitro is likely to account for their survival and assembly into stable LM-like structures when implanted into a mouse vascularised chamber model. This in vivo xenograft model will provide the basis of future studies of LM biology and testing of potential pharmacological interventions for patients with lymphatic malformations.
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Affiliation(s)
- Zerina Lokmic
- O'Brien Institute, 42 Fitzroy Street, Fitzroy, VIC, 3065, Australia,
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21
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Yap KK, Dingle AM, Palmer JA, Dhillon RS, Lokmic Z, Penington AJ, Yeoh GC, Morrison WA, Mitchell GM. Enhanced liver progenitor cell survival and differentiation in vivo by spheroid implantation in a vascularized tissue engineering chamber. Biomaterials 2013; 34:3992-4001. [DOI: 10.1016/j.biomaterials.2013.02.011] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2013] [Accepted: 02/06/2013] [Indexed: 12/24/2022]
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22
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Tilkorn DJ, Davies EM, Keramidaris E, Dingle AM, Gerrand YW, Taylor CJ, Han XL, Palmer JA, Penington AJ, Mitchell CA, Morrison WA, Dusting GJ, Mitchell GM. The in vitro preconditioning of myoblasts to enhance subsequent survival in an in vivo tissue engineering chamber model. Biomaterials 2012; 33:3868-79. [PMID: 22369961 DOI: 10.1016/j.biomaterials.2012.02.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2012] [Accepted: 02/02/2012] [Indexed: 12/27/2022]
Abstract
The effects of in vitro preconditioning protocols on the ultimate survival of myoblasts implanted in an in vivo tissue engineering chamber were examined. In vitro testing: L6 myoblasts were preconditioned by heat (42 °C; 1.5 h); hypoxia (<8% O(2); 1.5 h); or nitric oxide donors: S-nitroso-N-acetylpenicillamine (SNAP, 200 μM, 1.5 h) or 1-[N-(2-aminoethyl)-N-(2-aminoethyl)amino]-diazen-1-ium-1,2-diolate (DETA-NONOate, 500 μM, 7 h). Following a rest phase preconditioned cells were exposed to 24 h hypoxia, and demonstrated minimal overall cell loss, whilst controls (not preconditioned, but exposed to 24 h hypoxia) demonstrated a 44% cell loss. Phosphoimmunoblot analysis of pro-survival signaling pathways revealed significant activation of serine threonine kinase Akt with DETA-NONOate (p < 0.01) and heat preconditioning (p < 0.05). DETA-NONOate also activated ERK 1/2 signaling (p < 0.05). In vivo implantation: 100,000 preconditioned (heat, hypoxia, or DETA-NONOate) myoblasts were implanted in SCID mouse tissue engineering chambers. 100,000 (not preconditioned) myoblasts were implanted in control chambers. At 3 weeks, morphometric assessment of surviving myoblasts indicated myoblast percent volume (p = 0.012) and myoblasts/mm(2) (p = 0.0005) overall significantly increased in preconditioned myoblast chambers compared to control, with DETA-NONOate-preconditioned myoblasts demonstrating the greatest increase in survival (p = 0.007 and p = 0.001 respectively). DETA-NONOate therefore has potential therapeutic benefits to significantly improve survival of transplanted cells.
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Affiliation(s)
- Daniel J Tilkorn
- Department of Plastic Surgery, Burn Center, Hand Center, BG-University-Hospital Bergmannsheil, Ruhr-University Bochum, Germany
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Chin LC, Kumar P, Palmer JA, Rophael JA, Dolderer JH, Thomas GPL, Morrison WA, Penington AJ, Stewart AG, Mitchell GM. The influence of nitric oxide synthase 2 on cutaneous wound angiogenesis. Br J Dermatol 2012; 165:1223-35. [PMID: 21895624 DOI: 10.1111/j.1365-2133.2011.10599.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
BACKGROUND Inducible nitric oxide synthase (nitric oxide synthase 2, NOS 2) inhibition significantly suppresses chronically ischaemic skin flap survival, possibly because of reduced angiogenesis. OBJECTIVES To investigate the effect of genetic NOS 2 inhibition on cutaneous wound angiogenesis in two in vivo murine models. The impact of NOS 2 manipulation on vascular endothelial growth factor (VEGF)-A stimulated and fibroblast growth factor (FGF)-2 stimulated angiogenesis was also investigated in the Matrigel(®) plug assay. METHODS (i) Matrigel plugs/incisional wounds: two groups of NOS 2-/- mice and two groups of wild-type (WT) mice had bilateral Matrigel plugs containing 500 ng mL(-1) VEGF-A or 1000 ng mL(-1) FGF-2 injected subcutaneously in the abdomen. A 2·5 cm long dorsal incisional skin wound was created and sutured closed in the same animals. Wounds and plugs were explored at 7 or 12 days. (ii) Excisional wounds: dorsal 0·5 × 1·0 cm excisional skin wounds were created in four groups (two NOS 2-/- and two WT) and explored at 7 or 14 days. Wounds and Matrigel plugs were examined histologically and morphometrically for determination of percentage vascular volume (PVV). RESULTS The PVV in NOS 2-/- incisional wounds and excisional wounds was significantly less than in WT wounds (P = 0·05 and P < 0·001, respectively). The PVV was significantly less in VEGF-A stimulated Matrigel plugs compared with FGF-2 stimulated plugs in NOS 2-/- mice (P < 0·01), but not in WT mice. CONCLUSIONS NOS 2 is significantly involved in angiogenic signalling in healing skin wounds, particularly within the first 7 days. However, Matrigel plug vascularization suggests that the role of NOS 2 in angiogenesis is related to VEGF-A but not FGF-2 stimulated angiogenesis.
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Affiliation(s)
- L C Chin
- The O'Brien Institute and University of Melbourne, Department of Surgery at St Vincent's Hospital, 42 Fitzroy Street, Fitzroy, Vic. 3065, Australia
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Abstract
The physiological processes involved in tissue development and regeneration also include the parallel formation of blood and lymphatic vessel circulations which involves their growth, maturation and remodelling. Both vascular systems are also frequently involved in the development and progression of pathological conditions in tissues and organs. The blood vascular system circulates oxygenated blood and nutrients at appropriate physiological levels for tissue survival, and efficiently removes all waste products including carbon dioxide. This continuous network consists of the heart, aorta, arteries, arterioles, capillaries, post-capillary venules, venules, veins and vena cava. This system exists in an interstitial environment together with the lymphatic vascular system, including lymph nodes, which aids maintenance of body fluid balance and immune surveillance. To understand the process of vascular development, vascular network stability, remodelling and/or regression in any research model under any experimental conditions, it is necessary to clearly and unequivocally identify and quantify all elements of the vascular network. By utilising stereological methods in combination with cellular markers for different vascular cell components, it is possible to estimate parameters such as surface density and surface area of blood vessels, length density and length of blood vessels as well as absolute vascular volume. This review examines the current strategies used to visualise blood vessels and lymphatic vessels in two- and three-dimensions and the basic principles of vascular stereology used to quantify vascular network parameters.
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Affiliation(s)
- Zerina Lokmic
- Bernard O'Brien Institute of Microsurgery and the University of Melbourne and St Vincent's Hospital Department of Surgery, 42 Fitzroy Street, Fitzroy, Victoria 3065, Australia.
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Forster N, Palmer JA, Yeoh G, Ong WC, Mitchell GM, Slavin J, Tirnitz-Parker J, Morrison WA. Expansion and Hepatocytic Differentiation of Liver Progenitor Cells In Vivo Using a Vascularized Tissue Engineering Chamber in Mice. Tissue Eng Part C Methods 2011; 17:359-66. [DOI: 10.1089/ten.tec.2009.0519] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Affiliation(s)
- Natasha Forster
- Bernard O'Brien Institute of Microsurgery, St. Vincent's Hospital, Fitzroy, Australia
| | - Jason A. Palmer
- Bernard O'Brien Institute of Microsurgery, St. Vincent's Hospital, Fitzroy, Australia
| | - George Yeoh
- Centre for Medical Research, Western Australian Institute for Medical Research and School of Biomedical, Biomolecular and Chemical Sciences, University of Western Australia, Crawley, Australia
| | - Wei-Chen Ong
- Bernard O'Brien Institute of Microsurgery, St. Vincent's Hospital, Fitzroy, Australia
| | - Geraldine M. Mitchell
- Bernard O'Brien Institute of Microsurgery, St. Vincent's Hospital, Fitzroy, Australia
| | - John Slavin
- Department of Pathology, St. Vincent's Hospital, Melbourne, Australia
| | - Janina Tirnitz-Parker
- Centre for Medical Research, Western Australian Institute for Medical Research and School of Biomedical, Biomolecular and Chemical Sciences, University of Western Australia, Crawley, Australia
| | - Wayne A. Morrison
- Bernard O'Brien Institute of Microsurgery, St. Vincent's Hospital, Fitzroy, Australia
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Tilkorn DJ, Lokmic Z, Chaffer CL, Mitchell GM, Morrison WA, Thompson EW. Disparate companions: tissue engineering meets cancer research. Cells Tissues Organs 2010; 192:141-57. [PMID: 20357428 DOI: 10.1159/000308892] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/17/2009] [Indexed: 11/19/2022] Open
Abstract
Recreating an environment that supports and promotes fundamental homeostatic mechanisms is a significant challenge in tissue engineering. Optimizing cell survival, proliferation, differentiation, apoptosis and angiogenesis, and providing suitable stromal support and signalling cues are keys to successfully generating clinically useful tissues. Interestingly, those components are often subverted in the cancer setting, where aberrant angiogenesis, cellular proliferation, cell signalling and resistance to apoptosis drive malignant growth. In contrast to tissue engineering, identifying and inhibiting those pathways is a major challenge in cancer research. The recent discovery of adult tissue-specific stem cells has had a major impact on both tissue engineering and cancer research. The unique properties of these cells and their role in tissue and organ repair and regeneration hold great potential for engineering tissue-specific constructs. The emerging body of evidence implicating stem cells and progenitor cells as the source of oncogenic transformation prompts caution when using these cells for tissue-engineering purposes. While tissue engineering and cancer research may be considered as opposed fields of research with regard to their proclaimed goals, the compelling overlap in fundamental pathways underlying these processes suggests that cross-disciplinary research will benefit both fields. In this review article, tissue engineering and cancer research are brought together and explored with regard to discoveries that may be of mutual benefit.
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Affiliation(s)
- Daniel J Tilkorn
- Bernard O'Brien Institute of Microsurgery, University of Melbourne, St. Vincent's Hospital, Australia.
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Tilkorn DJ, Bedogni A, Keramidaris E, Han X, Palmer JA, Dingle AM, Cowling BS, Williams MD, McKay SM, Pepe L, Deftereos A, Morrison WA, Penington AJ, Mitchell GM. Implanted Myoblast Survival Is Dependent on the Degree of Vascularization in a Novel Delayed Implantation/Prevascularization Tissue Engineering Model. Tissue Eng Part A 2010; 16:165-78. [DOI: 10.1089/ten.tea.2009.0075] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Daniel J. Tilkorn
- Department of Plastic Surgery, Burn Center, Hand Center, BG-University-Hospital Bergmannsheil, Ruhr-University Bochum, Germany
| | - Alberto Bedogni
- Unit of Dentistry and Maxillofacial Surgery, University of Verona, Verona, Italy
| | - Effie Keramidaris
- Bernard O'Brien Institute of Microsurgery and University of Melbourne, Department of Surgery at St. Vincent's Hospital, Melbourne, Australia
| | - XiaoLian Han
- Bernard O'Brien Institute of Microsurgery and University of Melbourne, Department of Surgery at St. Vincent's Hospital, Melbourne, Australia
| | - Jason A. Palmer
- Bernard O'Brien Institute of Microsurgery and University of Melbourne, Department of Surgery at St. Vincent's Hospital, Melbourne, Australia
| | - Aaron M. Dingle
- Bernard O'Brien Institute of Microsurgery and University of Melbourne, Department of Surgery at St. Vincent's Hospital, Melbourne, Australia
| | | | - Michael D. Williams
- Bernard O'Brien Institute of Microsurgery and University of Melbourne, Department of Surgery at St. Vincent's Hospital, Melbourne, Australia
| | - Sue M. McKay
- Experimental, Medical, and Surgical Unit, St. Vincent's Hospital, Melbourne, Australia
| | - Liliana Pepe
- Experimental, Medical, and Surgical Unit, St. Vincent's Hospital, Melbourne, Australia
| | - Anna Deftereos
- Experimental, Medical, and Surgical Unit, St. Vincent's Hospital, Melbourne, Australia
| | - Wayne A. Morrison
- Bernard O'Brien Institute of Microsurgery and University of Melbourne, Department of Surgery at St. Vincent's Hospital, Melbourne, Australia
| | - Anthony J. Penington
- Bernard O'Brien Institute of Microsurgery and University of Melbourne, Department of Surgery at St. Vincent's Hospital, Melbourne, Australia
| | - Geraldine M. Mitchell
- Bernard O'Brien Institute of Microsurgery and University of Melbourne, Department of Surgery at St. Vincent's Hospital, Melbourne, Australia
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Simcock JW, Penington AJ, Morrison WA, Thompson EW, Mitchell GM. Endothelial Precursor Cells Home to a Vascularized Tissue Engineering Chamber by Application of the Angiogenic Chemokine CXCL12. Tissue Eng Part A 2009; 15:655-64. [DOI: 10.1089/ten.tea.2007.0438] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
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Lokmic Z, Thomas JL, Morrison WA, Thompson EW, Mitchell GM. An endogenously deposited fibrin scaffold determines construct size in the surgically created arteriovenous loop chamber model of tissue engineering. J Vasc Surg 2008; 48:974-85. [PMID: 18723310 DOI: 10.1016/j.jvs.2008.05.021] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2008] [Revised: 05/01/2008] [Accepted: 05/10/2008] [Indexed: 11/18/2022]
Abstract
BACKGROUND An arteriovenous loop (AVL) enclosed in a polycarbonate chamber in vivo, produces a fibrin exudate which acts as a provisional matrix for the development of a tissue engineered microcirculatory network. OBJECTIVES By administering enoxaparin sodium - an inhibitor of fibrin polymerization, the significance of fibrin scaffold formation on AVL construct size (including the AVL, fibrin scaffold, and new tissue growth into the fibrin), growth, and vascularization were assessed and compared to controls. METHODS In Sprague Dawley rats, an AVL was created on femoral vessels and inserted into a polycarbonate chamber in the groin in 3 control groups (Series I) and 3 experimental groups (Series II). Two hours before surgery and 6 hours post-surgery, saline (Series I) or enoxaparin sodium (0.6 mg/kg, Series II) was administered intra-peritoneally. Thereafter, the rats were injected daily with saline (Series I) or enoxaparin sodium (1.5 mg/kg, Series II) until construct retrieval at 3, 10, or 21 days. The retrieved constructs underwent weight and volume measurements, and morphologic/morphometric analysis of new tissue components. RESULTS Enoxaparin sodium treatment resulted in the development of smaller AVL constructs at 3, 10, and 21 days. Construct weight and volume were significantly reduced at 10 days (control weight 0.337 +/- 0.016 g [Mean +/- SEM] vs treated 0.228 +/- 0.048, [P < .001]: control volume 0.317 +/- 0.015 mL vs treated 0.184 +/- 0.039 mL [P < .01]) and 21 days (control weight 0.306 +/- 0.053 g vs treated 0.198 +/- 0.043 g [P < .01]: control volume 0.285 +/- 0.047 mL vs treated 0.148 +/- 0.041 mL, [P < .01]). Angiogenesis was delayed in the enoxaparin sodium-treated constructs with the absolute vascular volume significantly decreased at 10 days (control vascular volume 0.029 +/- 0.03 mL vs treated 0.012 +/- 0.002 mL [P < .05]). CONCLUSION In this in vivo tissue engineering model, endogenous, extra-vascularly deposited fibrin volume determines construct size and vascular growth in the first 3 weeks and is, therefore, critical to full construct development.
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Affiliation(s)
- Zerina Lokmic
- Bernard O'Brien Institute of Microsurgery, Melbourne, Australia
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Affiliation(s)
- Zerina Lokmic
- Bernard O'Brien Institute of Microsurgery, Melbourne, Victoria, Australia
- Institute for Physiological Chemistry and Pathobiochemistry, Muenster, Germany
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Craft RO, Rophael J, Morrison WA, Vashi AV, Mitchell GM, Penington AJ. Effect of local, long-term delivery of platelet-derived growth factor (PDGF) on injected fat graft survival in severe combined immunodeficient (SCID) mice. J Plast Reconstr Aesthet Surg 2008; 62:235-43. [PMID: 18178534 DOI: 10.1016/j.bjps.2007.11.017] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2007] [Accepted: 11/01/2007] [Indexed: 10/22/2022]
Abstract
SUMMARY BACKGROUND Autogenous fat injection is widely used for the correction of acquired and congenital soft tissue defects. However, the high absorption rate results in the need for over-correction of the defect and repeat procedures. We hypothesised that platelet-derived growth factor (PDGF), a potent mitogen and known stimulant for murine preadipocytes, would improve fat graft survival when concentrations were sustained with a gelatine microsphere delivery system. METHODS Abdominal fat was harvested from an otherwise healthy 43-year-old woman during a breast reconstruction. Prior to subdermal injection into severe combined immunodeficient (SCID) mice, the fat grafts were divided into 1-ml aliquots, mixed with microspheres bound to PDGF, free PDGF, or nothing depending on its experimental group, and weighed. The following experimental groups were thus created (minimum n=8 per group): (1) fat graft control, (2) fat graft with free PDGF, (3) fat graft with blank microspheres, and (4) fat graft with microspheres bound to PDGF. After 12 weeks, the fat xenografts were harvested for analysis of weight maintenance and histological and morphometric evaluation. RESULTS The addition of PDGF bound to gelatine microspheres was effective in improving xenograft weight maintenance (P=0.018) and preservation of adipose tissue architecture (P<0.0005) compared to controls at 3 months. The microspheres were completely absorbed at 12 weeks. CONCLUSIONS Sustained, local delivery of PDGF via a gelatine microsphere delivery system resulted in improved weight maintenance of the xenografts with greater preservation of adipose tissue architecture at 3 months compared to controls.
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Affiliation(s)
- Randall O Craft
- Bernard O'Brien Institute of Microsurgery, St. Vincent's Hospital, Fitzroy, Victoria, Australia
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Rophael JA, Craft RO, Palmer JA, Hussey AJ, Thomas GPL, Morrison WA, Penington AJ, Mitchell GM. Angiogenic growth factor synergism in a murine tissue engineering model of angiogenesis and adipogenesis. Am J Pathol 2007; 171:2048-57. [PMID: 18055559 DOI: 10.2353/ajpath.2007.070066] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
De novo tissue generation stimulated by three angiogenic growth factors administered in a factorial design was studied in an in vivo murine tissue engineering chamber. A silicone chamber was implanted around the epigastric pedicle and filled with Matrigel with 100 ng/ml of recombinant mouse vascular endothelial growth factor-120 (VEGF120), recombinant human basic fibroblastic growth factor (FGF-2), or recombinant rat platelet-derived growth factor-BB (PDGF-BB) added as single, double, or triple combinations. Angiogenesis, supporting tissue ingrowth, and adipogenesis were assessed at 2 and 6 weeks by immunohistochemistry and morphometry. At 2 weeks angiogenesis was synergistically enhanced by VEGF120 + FGF-2 (P = 0.019). FGF-2 (P = 0.008) and PDGF-BB (P = 0.01) significantly increased connective tissue/inflammatory cell infiltrate (macrophages, pericytes, and preadipocytes) in double and triple combinations compared with control. At 6 weeks sequential addition of growth factors increased the percent volume of adipose tissue (P < 0.0005, each main effect), with a synergistic increase in adipose tissue in combination treatments (P < 0.0005). Groups containing 300 ng/ml of single growth factors produced significantly less adipose tissue than the triple growth factor combination (P < 0.0005, VEGF120 and PDGF-BB; P < 0.001, FGF-2). In conclusion, angiogenic growth factor combinations increased early angiogenesis and cell infiltration resulting in synergistically increased adipose tissue growth at 6 weeks. Two way and higher level synergies are likely to be important in therapeutic applications of angiogenic growth factors.
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Affiliation(s)
- John A Rophael
- Bernard O'Brien Institute of Microsurgery, St Vincent's Hospital, 42 Fitzroy St., Fitzroy, Victoria, 3065, Australia
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Lokmic Z, Mitchell GM. The source and commencement of angiogenesis from the arterio-venous loop model. Microvasc Res 2007; 75:142-3. [PMID: 17950761 DOI: 10.1016/j.mvr.2007.09.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2007] [Revised: 09/05/2007] [Accepted: 09/05/2007] [Indexed: 10/22/2022]
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Lokmic Z, Darby IA, Thompson EW, Mitchell GM. Time course analysis of hypoxia, granulation tissue and blood vessel growth, and remodeling in healing rat cutaneous incisional primary intention wounds. Wound Repair Regen 2006; 14:277-88. [PMID: 16808806 DOI: 10.1111/j.1743-6109.2006.00122.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Hypoxia and the development and remodeling of blood vessels and connective tissue in granulation tissue that forms in a wound gap following full-thickness skin incision in the rat were examined as a function of time. A 1.5 cm-long incisional wound was created in rat groin skin and the opposed edges sutured together. Wounds were harvested between 3 days and 16 weeks and hypoxia, percent vascular volume, cell proliferation and apoptosis, alpha-smooth muscle actin, vascular endothelial growth factor-A, vascular endothelial growth factor receptor-2, and transforming growth factor-beta1 expression in granulation tissue were then assessed. Hypoxia was evident between 3 and 7 days while maximal cell proliferation at 3 days (123.6+/-22.2 cells/mm2, p<0.001 when compared with normal skin) preceded the peak percent vascular volume that occurred at 7 days (15.83+/-1.10%, p<0.001 when compared with normal skin). The peak in cell apoptosis occurred at 3 weeks (12.1+/-1.3 cells/mm2, p<0.001 when compared with normal skin). Intense alpha-smooth muscle actin labeling in myofibroblasts was evident at 7 and 10 days. Vascular endothelial growth factor receptor-2 and vascular endothelial growth factor-A were detectable until 2 and 3 weeks, respectively, while transforming growth factor-beta1 protein was detectable in endothelial cells and myofibroblasts until 3-4 weeks and in the extracellular matrix for 16 weeks. Incisional wound granulation tissue largely developed within 3-7 days in the presence of hypoxia. Remodeling, marked by a decline in the percent vascular volume and increased cellular apoptosis, occurred largely in the absence of detectable hypoxia. The expression of vascular endothelial growth factor-A, vascular endothelial growth factor receptor-2, and transforming growth factor-beta1 is evident prior, during, and after the peak of vascular volume reflecting multiple roles for these factors during wound healing.
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Affiliation(s)
- Zerina Lokmic
- Bernard O'Brien Institute of Microsurgery and University of Melbourne Department of Surgery, St. Vincent's Hospital, Melbourne, Australia
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Lokmic Z, Stillaert F, Morrison WA, Thompson EW, Mitchell GM. An arteriovenous loop in a protected space generates a permanent, highly vascular, tissue‐engineered construct. FASEB J 2006; 21:511-22. [PMID: 17172640 DOI: 10.1096/fj.06-6614com] [Citation(s) in RCA: 120] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
A major obstacle to 3-dimensional tissue engineering is incorporation of a functional vascular supply to support the expanding new tissue. This is overcome in an in vivo intrinsic vascularization model where an arteriovenous loop (AVL) is placed in a noncollapsible space protected by a polycarbonate chamber. Vascular development and hypoxia were examined from 3 days to 112 days by vascular casting, morphometric, and morphological techniques to understand the model's vascular growth and remodeling parameters for tissue engineering purposes. At 3 days a fibrin exudate surrounded the AVL, providing a scaffold to migrating inflammatory, endothelial, and mesenchymal cells. Capillaries formed between 3 and 7 days. Hypoxia and cell proliferation were maximal at 7 days, followed by a peak in percent vascular volume at 10 days (23.20+/-3.14% compared with 3.59+/-2.68% at 3 days, P<0.001). Maximal apoptosis was observed at 112 days. The protected space and spontaneous microcirculatory development in this model suggest it would be applicable for in vivo tissue engineering. A temporal window in a period of intense angiogenesis at 7 to 10 days is optimal for exogenous cell seeding and survival in the chamber, potentially enabling specific tissue outcomes to be achieved.
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Affiliation(s)
- Zerina Lokmic
- Bernard O'Brien Institute of Microsurgery and University of Melbourne Department of Surgery, St. Vincent's Hospital, Melbourne, Victoria, Australia
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Hofer SOP, Mitchell GM, Penington AJ, Morrison WA, RomeoMeeuw R, Keramidaris E, Palmer J, Knight KR. The use of pimonidazole to characterise hypoxia in the internal environment of an in vivo tissue engineering chamber. ACTA ACUST UNITED AC 2005; 58:1104-14. [PMID: 16043148 DOI: 10.1016/j.bjps.2005.04.033] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2004] [Revised: 04/10/2005] [Accepted: 04/27/2005] [Indexed: 01/06/2023]
Abstract
UNLABELLED The distribution of hypoxic cells in an in vivo tissue engineering chamber was investigated up to 28 days post-implantation. METHODS Arteriovenous loops were constructed and placed into bi-valved polycarbonate chambers containing 2 x 10(6) rat fibroblasts in basement membrane gel (BM gel). Chambers were inserted subcutaneously in the groin of male rats and harvested at 3 (n = 6), 7 (n = 6), 14 (n = 4) or 28 (n = 4) days. Ninety minutes before harvest, pimonidazole (60 mg/kg) was injected intraperitoneally. Chamber tissue was removed, immersion fixed, paraffin embedded, sectioned and stained immunohistochemically using hypoxyprobe-1 Mab that detects reduced pimonidazole adducts forming in cells, where pO2 < 10 mmHg. RESULTS At 3 days a fibrin clot/BM gel framework filled the chamber. Seeded fibroblasts had largely died. The majority of 3 day chambers did not demonstrate tissue growth from the AV loop nor was pimonidazole binding present in these chambers. In one chamber in which tissue growth had occurred strong pimonidazole binding was evident within the new tissue. In four out of six 7 day chambers a broader proliferative zone existed extending up to 0.4 mm (approximately) from the AV loop endothelium which demonstrated intense pimonidazole binding. The two remaining 7 day chambers displayed even greater tissue growth (leading edge > 0.7 mm from the AV loop endothelium), but very weak or no pimonidazole binding. At 14 and 28 days the fibrin/BM gel matrix was replaced by mature vascularised connective tissue that did not bind pimonidazole. CONCLUSION Employing a tissue engineering chamber, new tissue growth extending up to 0.4 mm from the AV loop endothelium (chambers < or = 7 days) demonstrated intense pimonidazole binding and, therefore, hypoxia. Tissue growth greater than 0.5 mm from the AV loop endothelium (7-28 days chambers) did not exhibit pimonidazole binding due to a significant increase in the number of new blood vessels and was, therefore, adequately oxygenated.
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Affiliation(s)
- S O P Hofer
- Bernard O'Brien Institute of Microsurgery and University of Melbourne, Department of Surgery at St Vincent's Hospital, Melbourne, Fitzroy, Vic. 3065, Australia
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Lokmic Z, Thompson EW, Morrison WA, Mitchell GM. ANGIOGENESIS IN TISSUE ENGINEERING. Cardiovasc Pathol 2004. [DOI: 10.1016/j.carpath.2004.03.545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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Kane AJ, Barker JE, Mitchell GM, Theile DRB, Romero R, Messina A, Wagh M, Fraulin FOG, Morrison WA, Stewart AG. Inducible nitric oxide synthase (iNOS) activity promotes ischaemic skin flap survival. Br J Pharmacol 2001; 132:1631-8. [PMID: 11309233 PMCID: PMC1572713 DOI: 10.1038/sj.bjp.0703944] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
We have examined the role of nitric oxide (NO) in a model of functional angiogenesis in which survival of a skin flap depends entirely on angiogenesis to provide an arterial blood supply to maintain tissue viability. The different effects of nitric oxide synthase (NOS) inhibitors on rat skin flap survival appeared to be explained on the basis of their NOS isoform selectivity. Skin flap survival was decreased by iNOS-selective (inducible NOS) inhibitors, S-methyl-isothiourea, aminoguanidine and aminoethylthiorea; unaffected by the non-selective inhibitor nitro-imino-L-ornithine; and enhanced by the cNOS (constitutive NOS, that is endothelial NOS (eNOS) and neuronal NOS (nNOS)) inhibitor, nitro-L-arginine methyl ester. Skin flap survival was reduced in mice with targeted disruption of the iNOS gene (iNOS knockout mice), and the administration of nitro-L-arginine methyl ester significantly increased flap survival in iNOS knockout mice (P<0.05). iNOS immunoreactivity was identified in mast cells in the angiogenic region. Immunoreactive vascular endothelial growth factor (VEGF) and basic fibroblast growth factor were also localized to mast cells. The combination of interferon-gamma and tumour necrosis factor-alpha induced NO production and increased VEGF levels in mast cells cultured from bone marrow of wild-type, but not iNOS KO mice. The increased tissue survival associated with the capacity for iNOS expression may be related to iNOS-dependent enhancement of VEGF levels and an ensuing angiogenic response. Our results provide both pharmacological and genetic evidence that iNOS activity promotes survival of ischaemic tissue.
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Affiliation(s)
- Anthony J Kane
- Bernard O'Brien Institute of Microsurgery, St Vincent's Hospital, Fitzroy, Victoria 3065, Australia
| | - Jane E Barker
- Bernard O'Brien Institute of Microsurgery, St Vincent's Hospital, Fitzroy, Victoria 3065, Australia
| | - Geraldine M Mitchell
- Bernard O'Brien Institute of Microsurgery, St Vincent's Hospital, Fitzroy, Victoria 3065, Australia
| | - David R B Theile
- Bernard O'Brien Institute of Microsurgery, St Vincent's Hospital, Fitzroy, Victoria 3065, Australia
| | - Rosalind Romero
- Bernard O'Brien Institute of Microsurgery, St Vincent's Hospital, Fitzroy, Victoria 3065, Australia
| | - Aurora Messina
- Bernard O'Brien Institute of Microsurgery, St Vincent's Hospital, Fitzroy, Victoria 3065, Australia
| | - Milind Wagh
- Bernard O'Brien Institute of Microsurgery, St Vincent's Hospital, Fitzroy, Victoria 3065, Australia
| | - Frankie O G Fraulin
- Bernard O'Brien Institute of Microsurgery, St Vincent's Hospital, Fitzroy, Victoria 3065, Australia
| | - Wayne A Morrison
- Bernard O'Brien Institute of Microsurgery, St Vincent's Hospital, Fitzroy, Victoria 3065, Australia
| | - Alastair G Stewart
- Department of Pharmacology, University of Melbourne, Parkville, Victoria 3052, Australia
- Author for correspondence:
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Abstract
Two cases are described in which patients presented 16 and 17 years, respectively, after complete or incomplete amputation/replantation of the arm. In case 1, the patient complained of coldness, pain, and tingling in the replanted arm in the previous 24 hours and noticed that his fingers had gone white. Arteriography and subsequent surgery revealed obliteration of the vein graft (inserted in the distal brachial artery) by neointimal thickening and atherosclerotic plaque, which was confirmed in a subsequent morphologic examination. In case 2, the patient presented with discomfort and a pulsatile swelling on the inner aspect of his upper arm. Arteriography and surgery revealed an aneurysm in the previously inserted vein graft in the brachial artery, with some atherosclerotic degeneration. Both vein grafts were successfully replaced with a fresh autologous vein graft and the patients remain well several years later. The 2 cases suggest that as part of replantation surgery of a limb, it is essential to maintain postoperative clinical monitoring for signs of graft degeneration in all patients with long-term vein graft insertion.
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Affiliation(s)
- W A Morrison
- Department of Surgery, University of Melbourne, St Vincent's Hospital, Fitzroy, Victoria, Australia
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Crowe DM, Hurley JV, Mitchell GM, Niazi Z, Morrison WA. Long-term studies of cold-stored rabbit femoral artery and vein autografts. Br J Plast Surg 1998; 51:291-9. [PMID: 9771347 DOI: 10.1054/bjps.1998.0020] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
UNLABELLED In previous studies we have shown that 80-100% of rabbit femoral vascular autografts cold-stored at 4 degrees C for 3 weeks remain patent 3 weeks after reinsertion in the femoral artery. The present study reports the effect on graft patency of increasing either the period of cold storage prior to reinsertion or the duration of reperfusion to 6 months. Rabbit femoral blood vessels were cold-stored (CS) at 4 degrees C for varying periods. CS autografts were reinserted into the contralateral leg for 3 weeks or 6 months. Graft patency was determined and grafts examined by histological, immunohistochemical and electron microscopical techniques. Six months after reinsertion patency of 4-week CS arterial and 1-week CS venous grafts was 40% and 27% respectively, very much lower than the 80-100% seen after 3 weeks reperfusion. Arterial grafts CS for 6 months had a patency rate of 70% after 3 weeks reperfusion but 0% after 6 months. Morphological examination suggests that the delayed failure of cold-stored vascular grafts is caused by thrombus superimposed on intimal hyperplasia within the graft. CONCLUSIONS Cold-stored vascular grafts are useful prostheses when only 3-4 weeks graft patency is required. They are not suitable for use when long-term graft patency is needed.
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Affiliation(s)
- D M Crowe
- Bernard O'Brien Institute of Microsurgery, St Vincent's Hospital, Melbourne, Australia
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Mitchell GM, McCann JJ, Rogers IW, Hickey MJ, Morrison WA, O'Brien BM. A morphological study of the long-term repair process in experimentally stretched but unruptured arteries and veins. Br J Plast Surg 1996; 49:34-40. [PMID: 8705100 DOI: 10.1016/s0007-1226(96)90184-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
As many avulsion amputations are incomplete and the vessels remain intact, the immediate pathology and long-term repair process (to 3 months post-injury) of experimentally stretched but unruptured rabbit femoral arteries and veins were examined. In stretched arteries, circumferential skip lesions involving endothelium, internal elastic lamina (IEL) and media occurred frequently and often up to 3 cm from the point of stretch. Medial smooth muscle cells (SMC) were significantly damaged or lost at lesions. Macrophages and neutrophils were found in lesions 1-4 days post-injury. Between 2-4 days, lesions were covered by endothelium and synthetic state SMC appeared in the media. At 1 week, a thin neointima (which persisted to 3 months) covered many lesions. The media at lesions gradually filled with SMC but generally remained disorganised even at 3 months post-injury. Stretching caused tears in vein walls, particularly close to the point of injury. There was no evidence of venous damage or repair in specimens examined 3 weeks and 3 months post-injury.
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Affiliation(s)
- G M Mitchell
- Bernard O'Brien Institute of Microsurgery, St Vincent's Hospital, Fitzroy, Victoria, Australia
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Eaton CJ, Mitchell GM, Crowe DM, Morrison WA, O'Brien BM. The effect of cold ischemia on the patency of microvascular repair following arterial avulsion injury. Plast Reconstr Surg 1995; 96:413-20. [PMID: 7624416 DOI: 10.1097/00006534-199508000-00024] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
UNLABELLED Avulsion injuries have a poor prognosis for survival in clinical replantation surgery. Arterial thrombosis is the most significant factor contributing to avulsion replant failure, and severe arterial damage has been observed with this injury. However, patency rates of experimentally avulsed arteries repaired immediately are much higher than in the clinical situation. This paper evaluates the effect of an added component--ischemia--on the patency of experimentally avulsed arteries. All avulsions seen clinically are subject to some degree of ischemia prior to replantation. Ninety rabbits had both femoral arteries avulsed under general anesthesia. A 6.5-cm graft was harvested from the left distal femoral artery. In 20 rabbits (group 1: 0 hours of ischemia) the graft was immediately inserted into the defect in the right femoral artery. Sixty rabbits (20 grafts per group) had their grafts stored at 4 degrees C for either 10 hours (group 2), 18 hours (group 3), or 24 hours (group 4) and reinserted into the right femoral artery in a second operation. Patency was assessed 3 weeks after reinsertion. Groups 1 and 2 maintained high patency rates (85 percent); however, group 3 (70 percent) and group 4 (45 percent) had lower patency rates than group 1, with a significant difference between groups 1 and 4 (p < 0.01). In a fifth group (10 grafts), avulsed 24-hour ischemic grafts were hydrodilated prior to reinsertion. The patency rate of this group increased significantly (90 percent) compared with group 4 (p < 0.005). CONCLUSION These experiments suggest that a combination of avulsion injury and ischemia time is responsible for the poor clinical results of avulsion replantations.
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Affiliation(s)
- C J Eaton
- Microsurgery Research Centre, St. Vincent's Hospital, Melbourne, Australia
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Olivier TV, Mitchell GM, Crowe DM, Romeo R, Gray KA, Morrison WA. Effects of cold storage on the subsequent structure and function of microvenous autografts. Br J Plast Surg 1994; 47:548-53. [PMID: 7697282 DOI: 10.1016/0007-1226(94)90138-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A study was undertaken to evaluate the structure and patency of cold stored rabbit femoral veins following reinsertion as autografts for 3 weeks. The periods of cold ischaemic storage were 1, 2, 3 and 4 weeks (n = 10/gp) and 6 and 10 weeks (n = 6/gp). All rabbits were subject to 3 operations under general anaesthesia. In the first, a 4 cm segment of left femoral vein was harvested and stored at 4 degrees C for the specified ischaemic interval. Following storage the graft was microsurgically reinserted at a second operation into the right femoral artery of the donor rabbit. Three weeks later, graft patency was assessed by surgical exploration and the graft processed for light and electron microscopy. Patency rates remained over 80% after 3 weeks in all groups except the 10 week storage group where only 1 of 6 (17%) grafts was patent at 3 weeks. In all groups normal vein structure was absent, being replaced by thin walled necrotic areas or by neointimal ingrowth. The excellent patency rates achieved indicate it is possible to cold preserve extra lengths of vein grafts harvested at initial operation for reuse should regrafting be necessary.
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Affiliation(s)
- T V Olivier
- Microsurgery Research Centre, St Vincent's Hospital, Melbourne, Victoria, Australia
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Crowe DM, Mitchell GM, Hurley JV, Olivier TV, O'Loughlin K, Morrison WA. Cold stored femoral vessels as microvascular allografts: a preliminary study. Microsurgery 1994; 15:712-6. [PMID: 7885218 DOI: 10.1002/micr.1920151009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Cold stored femoral arteries or veins have been reinserted successfully as autografts into rabbits. The present study examines whether grafting with cold stored vascular allografts is equally successful. Rabbit femoral arteries and veins were stored at 4 degrees C for 4 weeks before insertion as allografts into unrelated animals. Three weeks after insertion into the femoral artery all venous allografts and 80% of arterial allografts were patent, but patency of both graft types declined over the next few weeks. A small number of cold stored venous allografts when inserted into the femoral vein occluded within 3 weeks. No histological evidence of rejection was apparent. The findings suggest that cold stored vascular allografts could be used successfully as an arterial "prosthesis" to support free flaps where relatively short term patency is required until the flap can establish sufficient peripheral inset to survive in its own right. This technique could be applied when autologous veins are not available or not justified.
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Affiliation(s)
- D M Crowe
- Microsurgery Research Centre, St. Vincent's Hospital, Fitzroy, Australia
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45
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Gray KA, Mitchell GM, Gurusinghe CJ, Romeo R, Crowe DM, Olivier TV, Morrison WA. The functional and structural effects of hypothermic storage on ischaemic arterial grafts. Br J Plast Surg 1993; 46:570-5. [PMID: 8252263 DOI: 10.1016/0007-1226(93)90107-m] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The effects of hypothermic ischaemia on blood vessels are unknown. This study aimed to determine the 3 week patency rate and the pathology of 9 experimental groups of hypothermically stored ischaemic arteries and one control group in a rabbit femoral artery model. Ischaemia times were 0 h, 24 h, 1, 2, 4, 6, 8 and 10 weeks (Groups 1-8). Patency was over 80% in all groups after 3 weeks reinsertion. Following reinsertion control grafts maintained normal arterial structure, but cellular degeneration had occurred in all ischaemic grafts and appeared complete after 4 weeks ischaemia. The graft connective tissue framework frequently remained intact. Repair was evident in central graft regions after 2 weeks ischaemia and 3 weeks reinsertion, but occurred only adjacent to the anastomosis in 4-10 week ischaemic arteries. Four week ischaemic arteries (Groups 9 and 10) reinserted for 6 and 12 weeks respectively exhibited near complete repair but patency dropped to 60% in the 12 week group.
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Affiliation(s)
- K A Gray
- Microsurgery Research Centre, St Vincent's Hospital, Melbourne, Australia
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Mitchell GM. Is your insurance coverage up-to-date? Dent Econ 1992; 82:53-5. [PMID: 1499821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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Pederson WC, Singer DI, Angel MF, Mahoney JE, Mitchell GM, Morrison WA, O'Brien BM. Hydrostatic distention and pharmacological treatment of epinephrine-induced microarterial spasm. Ann Plast Surg 1989; 23:17-26. [PMID: 2764456 DOI: 10.1097/00000637-198907000-00004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The efficacy of using hydrodistention and vasodilatory drugs to relieve spasm in arteries was investigated. The femoral arteries of 64 rabbits (divided into five groups) were placed in spasm by the topical application of epinephrine (1 mg/ml). In group A (controls) vasospasm was induced without further treatment. In group B vasospasm was induced, and the arteries were hydrodistended with normal saline. In three additional groups vasospasm was induced and either 10% lidocaine hydrochloride (group C), verapamil hydrochloride (group D), or chlorpromazine hydrochloride (group E) was applied. Thirty minutes later the vessels were hydrodistended. All vessels were measured at set intervals, and some specimens were retained for light and electron microscopy. All methods of spasm relief were successful, although to varying degrees. Hydrodistention alone produced the widest dilation for the longest time. Lidocaine was the most successful drug treatment alone. Verapamil followed by hydrodistention was the most successful combination regimen, but did not produce better results than hydrodistention alone. Hydrodistention alone produced significant arterial wall damage, resulting in permanent structural modifications. Prior vasodilatory drug treatment reduced but did not eliminate hydrodistention damage. Although hydrodistention dilates for longer periods than vasodilatory drugs, the arterial wall damage associated with hydrodistention indicates that it should be used only when all other methods of vasodilation have failed.
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Affiliation(s)
- W C Pederson
- Division of Plastic, Reconstructive, Maxillofacial and Oral Surgery, Duke University Medical Center, Durham, NC
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Singer DI, Morrison WA, Gumley GJ, O'Brien BM, Mitchell GM, Barton RM, Frykman GK. Comparative study of vascularized and nonvascularized tendon grafts for reconstruction of flexor tendons in zone 2: an experimental study in primates. J Hand Surg Am 1989; 14:55-63. [PMID: 2723369 DOI: 10.1016/0363-5023(89)90059-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Vascularized tendon grafts were compared with nonvascularized tendon grafts in a primate experimental model. In four monkeys, seven vascularized extensor hallucis longus grafts were placed in the foot's digital fibroosseous canal and these were compared with eight nonvascularized tendon grafts similarly placed in the opposite extremities. The juncture techniques and postoperative protocols were identical for both tendon groups. All tendons were explored 5 months after insertion. The vascular pedicle was patent in all vascularized tendons. Three tendon ruptures occurred in nonvascularized tendons and only one rupture occurred in a vascularized tendon. The digits with vascularized tendons demonstrated a significantly better simulated total active motion (117 degrees versus 128 degrees, p less than 0.05) than digits with nonvascularized tendons. The difference was even more significant when a localized tenolysis of the proximal juncture of the tendon graft was performed (215 degrees versus 138 degrees, p less than 0.01). This study supports the concept that vascularized tendon grafts may be advantageous in scarred tendon beds.
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Affiliation(s)
- D I Singer
- Microsurgery Research Centre, St. Vincent's Hospital, Melbourne, Australia
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Sheen R, Mitchell GM, MacLeod AM, O'Brien BM. Intraoral mucosal reconstruction with microvascular free jejunal autografts: an experimental study. Br J Plast Surg 1988; 41:521-7. [PMID: 3179598 DOI: 10.1016/0007-1226(88)90011-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
This experimental study investigated the problem of covering bare bone adequately in the oral cavity to provide a stable, functionally acceptable reconstruction. In eight dogs, intraoral mucosal defects were created whilst preserving the mandibular arch. The defects were reconstructed with a microvascular jejunal patch. Six animals had their reconstructions stressed postoperatively by the administration of irradiation and by feeding solid food. Two control dogs did not receive irradiation. Grafts were assessed clinically and histologically for 6 months. Rapid mucosal healing occurred in seven of eight dogs. The grafts conformed well to the mandibular contour and were tolerant of postoperative radiotherapy and the chewing of solid food. Structural integrity of seven grafts was maintained although subtotal villous atrophy occurred in irradiated grafts and to a lesser extent in control grafts. In one animal whose graft mucosa sloughed, the wound was re-epithelialized from the adjacent buccal mucosa. Microvascular jejunal patches therefore provided a durable, functionally adequate reconstruction of the mouth floor.
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Affiliation(s)
- R Sheen
- Microsurgery Research Centre, St Vincent's Hospital, Melbourne, Australia
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Abstract
Changes in length, external diameter, wall thickness, and morphology were examined in 60 intraarterial vein grafts and 30 intravenous vein grafts inserted in rabbit femoral vessels. Half of each graft type was explored at 6 or 12 months, giving four experimental groups. The overall patency for intraarterial grafts at exploration was 98 percent and for intravenous grafts 100 percent. In comparison with the initial graft length resected, all four groups were significantly shorter at the completion of anastomosis, and three of the four groups also were significantly shorter at exploration. The overall loss in length of grafts varied between 26 and 30 percent of original length. External diameter was significantly increased (from between 133 and 201 percent) in all four groups at exploration compared to the normal femoral vein. Intravenous grafts maintained normal vein morphology to 12 months. Intraarterial grafts were modified by the ingrowth of smooth-muscle cells from the recipient artery, thereby creating a neointima that significantly thickened their walls at both 6 and 12 months.
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Affiliation(s)
- G M Mitchell
- Microsurgery Research Centre, St. Vincent's Hospital, Melbourne, Australia
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