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Zeng N, Chen Y, Wu Y, Zang M, Largo RD, Chang EI, Schaverien MV, Yu P, Zhang Q. Pre-epithelialized cryopreserved tracheal allograft for neo-trachea flap engineering. Front Bioeng Biotechnol 2023; 11:1196521. [PMID: 37214293 PMCID: PMC10198577 DOI: 10.3389/fbioe.2023.1196521] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 04/26/2023] [Indexed: 05/24/2023] Open
Abstract
Background: Tracheal reconstruction presents a challenge because of the difficulty in maintaining the rigidity of the trachea to ensure an open lumen and in achieving an intact luminal lining that secretes mucus to protect against infection. Methods: On the basis of the finding that tracheal cartilage has immune privilege, researchers recently started subjecting tracheal allografts to "partial decellularization" (in which only the epithelium and its antigenicity are removed), rather than complete decellularization, to maintain the tracheal cartilage as an ideal scaffold for tracheal tissue engineering and reconstruction. In the present study, we combined a bioengineering approach and a cryopreservation technique to fabricate a neo-trachea using pre-epithelialized cryopreserved tracheal allograft (ReCTA). Results: Our findings in rat heterotopic and orthotopic implantation models confirmed that tracheal cartilage has sufficient mechanical properties to bear neck movement and compression; indicated that pre-epithelialization with respiratory epithelial cells can prevent fibrosis obliteration and maintain lumen/airway patency; and showed that a pedicled adipose tissue flap can be easily integrated with a tracheal construct to achieve neovascularization. Conclusion: ReCTA can be pre-epithelialized and pre-vascularized using a 2-stage bioengineering approach and thus provides a promising strategy for tracheal tissue engineering.
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Affiliation(s)
| | | | | | | | | | | | | | - Peirong Yu
- Department of Plastic Surgery, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Qixu Zhang
- Department of Plastic Surgery, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
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Gao E, Wang P, Chen F, Xu Y, Wang Q, Chen H, Jiang G, Zhou G, Li D, Liu Y, Duan L. Skin-derived epithelial lining facilitates orthotopic tracheal transplantation by protecting the tracheal cartilage and inhibiting granulation hyperplasia. BIOMATERIALS ADVANCES 2022; 139:213037. [PMID: 35882125 DOI: 10.1016/j.bioadv.2022.213037] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 05/28/2022] [Accepted: 07/17/2022] [Indexed: 06/15/2023]
Abstract
Long-segment tracheal defects caused by tumours, inflammation or trauma can cause serious damage to the quality of life of patients. Although many novel neotracheas have been constructed, the therapeutic effect of orthotopic transplantation was compromised mainly because of the lack of an epithelial lining in those neotracheas. In this study, we aimed to investigate the therapeutic function of skin-derived epithelial lining for orthotopic tracheal transplantation. Strips of auricular cartilage with fixed interval were interrupted sutured on a silicone tube to mimic the cartilage rings of the native trachea. Neotrachea in the with epithelium group retained the unilateral skin as the epithelial lining in the lumen, whereas the neotrachea in the without epithelium group consisted solely of cartilage strips. After revascularized in the sternohyoid muscle, 2-cm-long tracheal defects were made and were reconstructed using these neotracheas. Our results showed that the skin-derived epithelial lining simultaneously protected the engineered tracheal cartilage and inhibited granulation hyperplasia in the tracheal lumen; further, compared with the without epithelium group, the group with epithelium showed a marked improvement in the tracheal lumen patency and the survival rate of rabbits. Our study provides a critical cue for improvements in the repair of tracheal defects via skin-derived epithelial lining and may significantly advance the clinical translation of tissue-engineered trachea.
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Affiliation(s)
- Erji Gao
- Department of Thoracic Surgery, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, China; Department of Plastic and Reconstructive Surgery, Shanghai 9th People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Pengli Wang
- Department of Thoracic Surgery, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Feifan Chen
- Department of Plastic and Reconstructive Surgery, Shanghai 9th People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Research Institute of Plastic Surgery, Weifang Medical College, Weifang, China
| | - Yong Xu
- Department of Thoracic Surgery, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, China; Department of Plastic and Reconstructive Surgery, Shanghai 9th People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Qianyi Wang
- Department of Plastic and Reconstructive Surgery, Shanghai 9th People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Research Institute of Plastic Surgery, Weifang Medical College, Weifang, China
| | - Hong Chen
- Department of Hand Surgery, Ningbo Sixth Hospital, Ningbo, China
| | - Gening Jiang
- Department of Thoracic Surgery, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Guangdong Zhou
- Department of Plastic and Reconstructive Surgery, Shanghai 9th People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Research Institute of Plastic Surgery, Weifang Medical College, Weifang, China.
| | - Dan Li
- Department of Plastic and Reconstructive Surgery, Shanghai 9th People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| | - Yi Liu
- Department of Plastic and Reconstructive Surgery, Shanghai 9th People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Institute of Dermatology, Chinese Academy of Medical Sciences, Nanjing, China.
| | - Liang Duan
- Department of Thoracic Surgery, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, China.
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Dennis JE, Bernardi KG, Kean TJ, Liou NE, Meyer TK. Tissue engineering of a composite trachea construct using autologous rabbit chondrocytes. J Tissue Eng Regen Med 2017; 12:e1383-e1391. [PMID: 28719734 DOI: 10.1002/term.2523] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 05/26/2017] [Accepted: 07/11/2017] [Indexed: 11/10/2022]
Abstract
The repair of large tracheal segmental defects remains an unsolved problem. The goal of this study is to apply tissue engineering principles for the fabrication of large segmental trachea replacements. Engineered tracheal replacements composed of autologous cells (neotracheas) were tested in a New Zealand White rabbit model. Neotracheas were formed in the rabbit neck by wrapping a silicone tube with consecutive layers of skin epithelium, platysma muscle, and an engineered cartilage sheet and allowing the construct to mature for 8-12 weeks. In total, 28 rabbits were implanted and the neotracheas assessed for tissue morphology. In 11 cases, neotracheas deemed sufficiently strong were used to repair segmental tracheal defects. Initially, the success rate of producing structurally sound neotracheas was impeded by physical disruption of the cartilage sheets during animal handling, but by the end of the study, 15 of 18 neotracheas (83.3%) were structurally sound. Of the 15 structurally sound neotracheas, 11 were used for segmental reconstruction and were left in place for up to 21 days. Histological examination showed the presence of variable amounts of viable epithelium, a vascularized platysma flap, and a layer of safranin O-positive cartilage along with evidence of endochondral ossification. Rabbits that had undergone segmental reconstruction showed good tracheal integration, had a viable epithelium with vascular support, and the cartilage was sufficiently strong to maintain a lumen when palpated. The results demonstrated that viable, trilayered, scaffold-free neotracheas could be constructed from autologous cells and could be integrated into native trachea to repair a segmental defect.
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Affiliation(s)
- James E Dennis
- Department of Orthopedic Surgery.,Matrix Biology Program, Benaroya Research Institute, Seattle, WA, USA
| | | | - Thomas J Kean
- Department of Orthopedic Surgery.,Matrix Biology Program, Benaroya Research Institute, Seattle, WA, USA
| | - Nelson E Liou
- Department of Otolaryngology Head and Neck Surgery, Baylor College of Medicine, Houston, TX, USA
| | - Tanya K Meyer
- Department of Otolaryngology Head and Neck Surgery, University of Washington, Seattle, WA, USA
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Ninkovic M, Buerger H, Ehrl D, Dornseifer U. One-stage reconstruction of tracheal defects with the medial femoral condyle corticoperiosteal-cutaneous free flap. Head Neck 2016; 38:1870-1873. [PMID: 27131047 DOI: 10.1002/hed.24491] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/21/2016] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND The demanding anatomic and mechanical requirements make the reconstruction of long tracheal defects challenging. Multiple attempts at replacing tracheal segments are described, including the use of autologous, allogeneic, and synthetic tissues. However, the multilayer structure of the trachea and its function as a conduit for air had generally resulted in the use of nonvascularized tissue and/or multistage procedures. METHODS The authors report on a 1-stage autologous reconstruction using local skin flaps for inner lining and a free medial femoral condyle corticoperiosteal-cutaneous (FCCPC) flap for the remaining layers. The skin island directly located over the FCCPC flap serves as an external coverage of the tracheal reconstruction. RESULTS Within the follow-up, the reconstructed trachea has retained its shape, diameter, and airway function. No notable stenosis or instability was observed. CONCLUSION This concept combines ideal biological and mechanical tissue properties, offering the potential to meet the reconstructive requirements for extended tracheal defects. © 2016 Wiley Periodicals, Inc. Head Neck 38: 1870-1873, 2016.
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Affiliation(s)
- Milomir Ninkovic
- Department of Plastic, Reconstructive, Hand, and Burn Surgery, Bogenhausen Academic Hospital, Munich, Germany
| | - Heinz Buerger
- Department of Oral and Maxillofacial Surgery, University Hospital, Salzburg, Austria
| | - Denis Ehrl
- Department of Plastic, Reconstructive, Hand, and Burn Surgery, Bogenhausen Academic Hospital, Munich, Germany
| | - Ulf Dornseifer
- Department of Plastic, Reconstructive, Hand, and Burn Surgery, Bogenhausen Academic Hospital, Munich, Germany
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Sarhaddi D, Poushanchi B, Merati M, Tchanque-Fossuo C, Donneys A, Baker J, Buchman SR. Validation of Histologic Bone Analysis Following Microfil Vessel Perfusion. J Histotechnol 2013. [PMID: 26207077 DOI: 10.1179/2046023612y.0000000012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
The ability to examine bone vascularity using Micro-Computed Tomography (μCT) following vessel perfusion with Microfil® and to subsequently perform histologic bone analysis in the same specimen would provide an efficient method by which the vascular and cellular environment of bone can be examined simultaneously. The purpose of this report is to determine if the administration of Microfil® precludes accurate histologic assessment of bone quality via osteocyte count and empty lacunae count. Sprague-Dawley rats (n=6) underwent perfusion with Microfil®. Left hemi-mandibles were harvested, decalcified and underwent vascular analysis via μCT prior to sectioning and staining with Gomori's Trichrome. Quantitative Histomorphometric evaluation was performed. Ninety-five percent confidence intervals were used to determine statistical differences from an established set of controls (n=12). Histologic analyses were successfully performed on specimens that had undergone previous perfusion. Quantitative measures of bone cellularity of perfused versus control specimens revealed no statistical difference in osteocyte count per high-power field (95.33 versus 94.66; 95 percent CI,-7.64 to 6.30) or empty lacunae per high-power field (2.73 versus 1.89, 95 percent CI, -1.81 to 0.13). Here we report a statistical validation allowing for histological analysis of cell counts in specimens in which Microfil® perfusion has previously been performed.
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Affiliation(s)
- D Sarhaddi
- The University of Michigan: Craniofacial Anomalies Program, Pediatric Plastic Surgery, 1500 E. Medical Center Drive, F7894 Mott Children's Hospital, Ann Arbor, Mich. 48109-5219
| | - B Poushanchi
- The University of Michigan: Craniofacial Anomalies Program, Pediatric Plastic Surgery, 1500 E. Medical Center Drive, F7894 Mott Children's Hospital, Ann Arbor, Mich. 48109-5219
| | - M Merati
- The University of Michigan: Craniofacial Anomalies Program, Pediatric Plastic Surgery, 1500 E. Medical Center Drive, F7894 Mott Children's Hospital, Ann Arbor, Mich. 48109-5219
| | - C Tchanque-Fossuo
- The University of Michigan: Craniofacial Anomalies Program, Pediatric Plastic Surgery, 1500 E. Medical Center Drive, F7894 Mott Children's Hospital, Ann Arbor, Mich. 48109-5219
| | - A Donneys
- The University of Michigan: Craniofacial Anomalies Program, Pediatric Plastic Surgery, 1500 E. Medical Center Drive, F7894 Mott Children's Hospital, Ann Arbor, Mich. 48109-5219
| | - J Baker
- The University of Michigan: Craniofacial Anomalies Program, Pediatric Plastic Surgery, 1500 E. Medical Center Drive, F7894 Mott Children's Hospital, Ann Arbor, Mich. 48109-5219
| | - S R Buchman
- The University of Michigan: Craniofacial Anomalies Program, Pediatric Plastic Surgery, 1500 E. Medical Center Drive, F7894 Mott Children's Hospital, Ann Arbor, Mich. 48109-5219
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Reconstruction of the (Crico)trachea for malignancy in the virgin and irradiated neck. J Plast Reconstr Aesthet Surg 2012; 65:1645-53. [DOI: 10.1016/j.bjps.2012.07.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2012] [Revised: 07/05/2012] [Accepted: 07/11/2012] [Indexed: 11/21/2022]
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Fibrin Gel as Alternative Scaffold for Respiratory Tissue Engineering. Ann Biomed Eng 2011; 40:679-87. [DOI: 10.1007/s10439-011-0437-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2011] [Accepted: 10/07/2011] [Indexed: 11/27/2022]
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Perichondrium directed cartilage formation in silk fibroin and chitosan blend scaffolds for tracheal transplantation. Acta Biomater 2011; 7:3422-31. [PMID: 21640205 DOI: 10.1016/j.actbio.2011.05.012] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2010] [Revised: 05/09/2011] [Accepted: 05/11/2011] [Indexed: 11/23/2022]
Abstract
The purpose of this study was to investigate the potential of silk fibroin and chitosan blend (SFCS) biological scaffolds for the purpose of cartilage tissue engineering with applications in tracheal tissue reconstruction. The capability of these scaffolds as cell carrier systems for chondrocytes was determined in vitro and cartilage generation in vivo on engineered chondrocyte-scaffold constructs with and without a perichondrium wrapping was tested in an in vivo nude mouse model. SFCS scaffolds supported chondrocyte adhesion, proliferation, and differentiation, determined as features of the cells based on the spherical cell morphology, increased accumulation of glycosaminoglycans, and increased collagen type II deposition with time within the scaffold framework. Perichondrium wrapping significantly (P<0.001) improved chondrogenesis within the cell-scaffold constructs in vivo. In vivo implantation for 6weeks did not generate cartilage structures resembling native trachea, although cartilage-like structures were present. The mechanical properties of the regenerated tissue increased due to the deposition of chondrogenic matrix within the SFCS scaffold structural framework of the trachea. The support of chondrogenesis by the SFCS tubular scaffold construct resulted in a mechanically sound structure and thus is a step towards an engineered trachea that could potentially support the growth of an epithelial lining resulting in a tracheal transplant with properties resembling those of the fully functional native trachea.
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Nguyen DH, Lee CL, Wu KY, Cheng MH. A novel approach to cervical reconstruction using vaginal mucosa-lined polytetrafluoroethylene graft in congenital agenesis of the cervix. Fertil Steril 2011; 95:2433.e5-8. [DOI: 10.1016/j.fertnstert.2011.02.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2010] [Revised: 01/31/2011] [Accepted: 02/02/2011] [Indexed: 10/18/2022]
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Overview of Tracheal Tissue Engineering: Clinical Need Drives the Laboratory Approach. Ann Biomed Eng 2011; 39:2091-113. [DOI: 10.1007/s10439-011-0318-1] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2010] [Accepted: 04/22/2011] [Indexed: 11/25/2022]
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Yu P, Clayman GL, Walsh GL. Long-term outcomes of microsurgical reconstruction for large tracheal defects. Cancer 2010; 117:802-8. [PMID: 20872878 DOI: 10.1002/cncr.25492] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2010] [Revised: 04/13/2010] [Accepted: 04/28/2010] [Indexed: 12/15/2022]
Abstract
BACKGROUND Reconstruction of large tracheal defects has been largely unsuccessful. The purpose of this study was to review the authors' experience with microsurgical reconstruction of these defects. METHODS Seven cases of microsurgical tracheal reconstruction were performed between May 2002 and April 2008. All but 1 patient had recurrent thyroid cancer; the other patient had primary adenocystic carcinoma of the trachea. The radial forearm free flap was used for lining in all cases. Rigid support was provided with a variety of prosthetic materials. RESULTS All defects involved the cervical trachea, with an average length of 5.8 cm ± 1.0 cm (range, 5 cm-7.5 cm). The width of defects ranged from half of the tracheal circumference to the entire circumference. Major complications included air leak in 4 patients, exposure and removal of prosthesis in 2 patients, and cardiopulmonary complications in 2 patients. One patient with postoperative retroperitoneal hematoma, abdominal compartment syndrome, and multiple organ failure died 2 months after surgery. Two patients died of other causes 1 year and 4 years, respectively, after surgery. The other 4 patients were alive and disease free, with follow-up ranging from 1 to 4.5 years. Four patients are asymptomatic, with normal speech and swallowing functions. Two patients remained tracheostomy dependent, but vocal ability was intact. All patients tolerated a regular diet. CONCLUSIONS Microsurgical reconstruction is a viable option in selected patients with large cervical tracheal defects that are beyond primary repair.
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Affiliation(s)
- Peirong Yu
- Department of Plastic Surgery, The University of Texas M. D. Anderson Cancer Center, Houston, Texas, USA.
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Reconstruction of the Cervical Trachea Using a Prefabricated Corticoperiosteal Flap From the Femur. Ann Plast Surg 2009; 62:633-6. [DOI: 10.1097/sap.0b013e31817f023e] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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13
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Fujiwara T, Nishino K, Numajiri T. Tracheal reconstruction with a prefabricated and double-folded radial forearm free flap. J Plast Reconstr Aesthet Surg 2009; 62:790-4. [DOI: 10.1016/j.bjps.2007.09.055] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2007] [Accepted: 09/05/2007] [Indexed: 11/27/2022]
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Abstract
In this review, we summarize the history of tracheal reconstruction and replacement as well as progress in current tracheal substitutes. In Part 1, we cover the historical highlights of grafts, flaps, tube construction, and tissue transplants and address the progress made in tracheal stenting as a means of temporary tracheal support. This is followed in Part 2 by an analysis of solid and porous tracheal prostheses in experimental and clinical trials. We conclude Part 2 with a summary of recent efforts toward generating a bioengineered trachea. Finally, we provide an algorithm on the spectrum of options available for tracheal replacement.
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Affiliation(s)
- Kristin A Kucera
- Department of Surgery, University of Texas Medical Branch, Galveston, Texas 77555, USA
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Goessler UR, Stern-Straeter J, Riedel K, Bran GM, Hörmann K, Riedel F. Tissue engineering in head and neck reconstructive surgery: what type of tissue do we need? Eur Arch Otorhinolaryngol 2007; 264:1343-56. [PMID: 17628823 DOI: 10.1007/s00405-007-0369-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2007] [Accepted: 05/25/2007] [Indexed: 01/14/2023]
Abstract
Craniofacial tissue loss due to congenital defects, disease or injury is a major clinical problem. The head and neck region is composed of several tissues. The most prevalent method of reconstruction is autologous grafting. Often, there is insufficient host tissue for adequate repair of the defect side, and extensive donor site morbidity may result from the secondary surgical procedure. The field of tissue engineering has the potential to create functional replacements for damaged or pathologic tissues.
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Affiliation(s)
- Ulrich Reinhart Goessler
- Department of Otolaryngology, Head and Neck Surgery, University Hospital Mannheim, University of Heidelberg, 68135, Mannheim, Germany.
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Schenke-Layland K, Riemann I, Damour O, Stock UA, König K. Two-photon microscopes and in vivo multiphoton tomographs--powerful diagnostic tools for tissue engineering and drug delivery. Adv Drug Deliv Rev 2006; 58:878-96. [PMID: 17011064 DOI: 10.1016/j.addr.2006.07.004] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2006] [Accepted: 07/13/2006] [Indexed: 12/13/2022]
Abstract
Near-infrared multiphoton microscopes and in vivo femtosecond laser tomographs are novel powerful diagnostic tools for intra-tissue drug screening and high-resolution structural imaging applicable to many areas of biomedical research. Deep tissue cells and extracellular matrix (ECM) compartments can be visualized in situ with submicron resolution without the need for tissue processing. In particular, the reduced fluorescent coenzyme NAD(P)H, flavoproteins, keratin, melanin, and elastin are detected by two-photon excited autofluorescence, whereas myosin, tubulin and the ECM protein collagen can be imaged additionally by second harmonic generation (SHG). Therefore, these innovative multiphoton technologies have been used to probe architecture and state of a variety of native tissues, as well as of tissue-engineered constructs, giving insights on the interaction between scaffolds and seeded cells in vitro prior implantation. Moreover, non-invasive 4-D multiphoton tomographs are employed in clinical studies to examine the diffusion behavior, the intra-tissue accumulation of topically applied cosmetic and pharmaceutical components, and their interaction with skin cells.
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Affiliation(s)
- Katja Schenke-Layland
- Cardiovascular Research Laboratory, University of California Los Angeles (UCLA), 675 Charles E. Young Drive South, MRL 3-579, Los Angeles, CA 90095-1760, USA.
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