47 results on '"Harald C. Ott"'
Search Results
2. Human-scale lung regeneration based on decellularized matrix scaffolds as a biologic platform
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Keiji Ohata and Harald C. Ott
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Pluripotent Stem Cells ,Pathology ,medicine.medical_specialty ,Scaffold ,Swine ,medicine.medical_treatment ,Review Article ,Extracellular matrix ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Lung transplantation ,Animals ,Humans ,Regeneration ,Lung regeneration ,Induced pluripotent stem cell ,Lung ,030304 developmental biology ,0303 health sciences ,Decellularization ,Bioartificial Organs ,Tissue Engineering ,Tissue Scaffolds ,business.industry ,Regeneration (biology) ,General Medicine ,respiratory system ,respiratory tract diseases ,Rats ,Transplantation ,Perfusion ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Models, Animal ,Surgery ,business - Abstract
Lung transplantation is currently the only curative treatment for patients with end-stage lung disease; however, donor organ shortage and the need for intense immunosuppression limit its broad clinical application. Bioartificial lungs created by combining native matrix scaffolds with patient-derived cells might overcome these problems. Decellularization involves stripping away cells while leaving behind the extracellular matrix scaffold. Cadaveric lungs are decellularized by detergent perfusion, and histologic examination confirms the absence of cellular components but the preservation of matrix proteins. The resulting lung scaffolds are recellularized in a bioreactor that provides biomimetic conditions, including vascular perfusion and liquid ventilation. Cell seeding, engraftment, and tissue maturation are achieved in whole-organ culture. Bioartificial lungs are transplantable, similarly to donor lungs, because the scaffolds preserve the vascular and airway architecture. In rat and porcine transplantation models, successful anastomoses of the vasculature and the airway were achieved, and gas exchange was evident after reperfusion. However, long-term function has not been achieved because of the immaturity of the vascular bed and distal lung epithelia. The goal of this strategy is to create patient-specific transplantable lungs using induced pluripotent stem cell (iPSC)-derived cells. The repopulation of decellularized scaffolds to create transplantable organs is one of possible future clinical applications of iPSCs.
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- 2020
3. Creation of Laryngeal Grafts from Primary Human Cells and Decellularized Laryngeal Scaffolds
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Gillian R. Diercks, Bernhard J. Jank, Daniele Evangelista-Leite, Xi Ren, Sarah E. Gilpin, Glenn R. Gaudette, Mattia F. M. Gerli, Harald C. Ott, Jonathan M. Charest, Christopher J. Hartnick, Philipp T. Moser, and Joshua R. Gershlak
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Male ,Larynx ,Pathology ,medicine.medical_specialty ,medicine.medical_treatment ,0206 medical engineering ,Biomedical Engineering ,Bioengineering ,Mice, SCID ,02 engineering and technology ,Biochemistry ,Rats, Sprague-Dawley ,Biomaterials ,03 medical and health sciences ,Dogs ,Tissue engineering ,Human Umbilical Vein Endothelial Cells ,Animals ,Humans ,Medicine ,Cells, Cultured ,Cell Proliferation ,030304 developmental biology ,0303 health sciences ,Decellularization ,Tissue Engineering ,Tissue Scaffolds ,business.industry ,Regeneration (biology) ,Cell Differentiation ,Tissue Graft ,020601 biomedical engineering ,Epithelium ,Laryngectomy ,Transplantation ,medicine.anatomical_structure ,Laryngeal Muscles ,business - Abstract
Current reconstruction methods of the laryngotracheal segment fail to replace the complex functions of the human larynx. Bioengineering approaches to reconstruction have been limited by the complex tissue compartmentation of the larynx. We attempted to overcome this limitation by bioengineering laryngeal grafts from decellularized canine laryngeal scaffolds recellularized with human primary cells under one uniform culture medium condition. First, we developed laryngeal scaffolds which were generated by detergent perfusion-decellularization over 9 days and preserved their glycosaminoglycan content and biomechanical properties of a native larynx. After subcutaneous implantations in rats for 14 days, the scaffolds did not elicit a CD3 lymphocyte response. We then developed a uniform culture medium that strengthened the endothelial barrier over 5 days after an initial growth phase. Simultaneously, this culture medium supported airway epithelial cell and skeletal myoblast growth while maintaining their full differentiation and maturation potential. We then applied the uniform culture medium composition to whole laryngeal scaffolds seeded with endothelial cells from both carotid arteries and external jugular veins and generated reendothelialized arterial and venous vascular beds. Under the same culture medium, we bioengineered epithelial monolayers onto laryngeal mucosa and repopulated intrinsic laryngeal muscle. We were then able to demonstrate early muscle formation in an intramuscular transplantation model in immunodeficient mice. We supported formation of three humanized laryngeal tissue compartments under one uniform culture condition, possibly a key factor in developing complex, multicellular, ready-to-transplant tissue grafts. Impact Statement For patients undergoing laryngectomy, no reconstruction methods are available to restore the complex functions of the human larynx. The first promising preclinical results have been achieved with the use of biological scaffolds fabricated from decellularized tissue. However, the complexity of laryngeal tissue composition remains a hurdle to create functional viable grafts, since previously each cell type requires tailored culture conditions. In this study, we report the de novo formation of three humanized laryngeal tissue compartments under one uniform culture condition, a possible keystone in creating vital composite tissue grafts for laryngeal regeneration.
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- 2020
4. Protease inhibitor Camostat Mesyalte blocks wild type SARS-CoV-2 and D614G viral entry in human engineered miniature lungs
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Tong Wu, Seyed A. Rabi, William A. Michaud, David Becerra, Sarah E. Gilpin, Mari Mino-Kenudson, and Harald C. Ott
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SARS-CoV-2 ,Biophysics ,COVID-19 ,Esters ,Bioengineering ,Virus Internalization ,Antiviral Agents ,Guanidines ,Rats ,Biomaterials ,Mechanics of Materials ,Ceramics and Composites ,Animals ,Humans ,Protease Inhibitors ,Lung - Abstract
The catastrophic global effects of the SARS-CoV-2 pandemic highlight the need to develop novel therapeutics strategies to prevent and treat viral infections of the respiratory tract. To enable this work, we need scalable, affordable, and physiologically relevant models of the human lung, the primary organ involved in the pathogenesis of COVID-19. To date, most COVID-19 in vitro models rely on platforms such as cell lines and organoids. While 2D and 3D models have provided important insights, human distal lung models that can model epithelial viral uptake have yet to be established. We hypothesized that by leveraging techniques of whole organ engineering and directed differentiation of induced pluripotent stem cells (iPSC) we could model human distal lung epithelium, examine viral infection at the tissue level in real time, and establish a platform for COVID-19 related research ex vivo. In the present study, we used type 2 alveolar epithelial cells (AT2) derived from human iPSCs to repopulate whole rat lung acellular scaffolds and maintained them in extended biomimetic organ culture for 30 days to induce the maturation of distal lung epithelium. We observed emergence of a mixed type 1 and type 2 alveolar epithelial phenotype during tissue formation. When exposing our system to a pseudotyped lentivirus containing the spike of wildtype SARS-CoV-2 and the more virulent D614G, we observed progression of the infection in real time. We then found that the protease inhibitor Camostat Mesyalte significantly reduced viral transfection in distal lung epithelium. In summary, our data show that a mature human distal lung epithelium can serve as a novel moderate throughput research platform to examine viral infection and to evaluate novel therapeutics ex vivo.
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- 2022
5. Metabolic glycan labeling and chemoselective functionalization of native biomaterials
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Xi Ren, Harald C. Ott, Konstantinos P. Economopoulos, Douglas J. Mathisen, Philipp T. Moser, Daniel Gorman, Taufiek Konrad Rajab, Tong Wu, Daniele Evangelista-Leite, Jordan P. Bloom, Haiyang Zhou, Jun Jie Tan, Sarah E. Gilpin, and Kentaro Kitano
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Male ,0301 basic medicine ,Azides ,Glycan ,Swine ,Biophysics ,Biocompatible Materials ,Bioengineering ,02 engineering and technology ,Rats, Sprague-Dawley ,Biomaterials ,Extracellular matrix ,03 medical and health sciences ,Tissue engineering ,Polysaccharides ,In vivo ,Animals ,Lung ,Bioconjugation ,Decellularization ,Staining and Labeling ,Tissue Scaffolds ,biology ,Heparin ,Chemistry ,Anticoagulants ,021001 nanoscience & nanotechnology ,Extracellular Matrix ,Rats ,Cell biology ,030104 developmental biology ,Mechanics of Materials ,Ceramics and Composites ,Click chemistry ,biology.protein ,Click Chemistry ,0210 nano-technology ,Ex vivo - Abstract
Decellularized native extracellular matrix (ECM) biomaterials are widely used in tissue engineering and have reached clinical application as biomesh implants. To enhance their regenerative properties and postimplantation performance, ECM biomaterials could be functionalized via immobilization of bioactive molecules. To facilitate ECM functionalization, we developed a metabolic glycan labeling approach using physiologic pathways to covalently incorporate click-reactive azide ligands into the native ECM of a wide variety of rodent tissues and organs in vivo, and into the ECM of isolated rodent and porcine lungs cultured ex vivo. The incorporated azides within the ECM were preserved after decellularization and served as chemoselective ligands for subsequent bioconjugation via click chemistry. As proof of principle, we generated alkyne-modified heparin, immobilized it onto azide-incorporated acellular lungs, and demonstrated its bioactivity by Antithrombin III immobilization and Factor Xa inhibition. The herein reported metabolic glycan labeling approach represents a novel platform technology for manufacturing click-reactive native ECM biomaterials, thereby enabling efficient and chemoselective functionalization of these materials to facilitate tissue regeneration and repair.
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- 2018
6. Orthotopic Transplantation of Human Bioartificial Lung Grafts in a Porcine Model: A Feasibility Study
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Harald C. Ott, Kentaro Kitano, David C. Becerra, Konstantinos P. Economopoulos, Sarah E. Gilpin, Daniel Gorman, and Keiji Ohata
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Pulmonary and Respiratory Medicine ,Pathology ,medicine.medical_specialty ,Swine ,medicine.medical_treatment ,030204 cardiovascular system & hematology ,Pulmonary vein ,03 medical and health sciences ,0302 clinical medicine ,medicine.artery ,Medicine ,Lung transplantation ,Animals ,Humans ,Vein ,Lung ,Decellularization ,Tissue Scaffolds ,business.industry ,Endothelial Cells ,Immunosuppression ,General Medicine ,respiratory system ,respiratory tract diseases ,Transplantation ,medicine.anatomical_structure ,Treatment Outcome ,030228 respiratory system ,Pulmonary artery ,Feasibility Studies ,Surgery ,Cardiology and Cardiovascular Medicine ,business ,Lung Transplantation - Abstract
Lung transplantation is the only treatment for end-stage lung disease; however, donor organ shortage and intense immunosuppression limit its broad clinical impact. Bioengineering of lungs with patient-derived cells could overcome these problems. We created bioartificial lungs by seeding human-derived cells onto porcine lung matrices and performed orthotopic transplantation to assess feasibility and in vivo function. Porcine decellularized lung scaffolds were seeded with human airway epithelial cells and human umbilical vein endothelial cells. Following in vitro culture, the bioartificial lungs were orthotopically transplanted into porcine recipients with planned 1-day survival (n = 3). Lungs were assessed with histology and in vivo function. Orthotopic transplantation of cadaveric lungs was performed as control. Engraftment of endothelial and epithelial cells in the grafts were histologically demonstrated. Technically successful orthotopic anastomoses of the vasculatures and airway were achieved in all animals. Perfusion and ventilation of the lung grafts were confirmed intraoperatively. The gas exchange function was evident immediately after transplantation; PO2 gradient between pulmonary artery and vein were 178 ± 153 mm Hg in the bioartificial lung group and 183 ± 117 mm Hg in the control group. At time of evaluation 24 hours after reperfusion, the pulmonary arteries were found to be occluded with thrombus in all bioartificial lungs. Engineering and orthotopic transplantation of bioartificial lungs with human cells were technically feasible in a porcine model. Early gas exchange function was evident. Further progress in optimizing recellularization and maturation of the grafts will be necessary for sustained perfusability and function.
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- 2021
7. Bioengineering of functional human induced pluripotent stem cell-derived intestinal grafts
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Sarah E. Gilpin, Allan M. Goldstein, Dana M. Schwartz, Cesar Sommer, Amalia Capilla, Harald C. Ott, Douglas J. Mathisen, Gustavo Mostoslavsky, Gregory R. Wojtkiewicz, Kentaro Kitano, Haiyang Zhou, and Xi Ren
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Male ,Short Bowel Syndrome ,0301 basic medicine ,Pathology ,medicine.medical_specialty ,Endothelium ,Science ,Induced Pluripotent Stem Cells ,Transplants ,General Physics and Astronomy ,Bioengineering ,Article ,General Biochemistry, Genetics and Molecular Biology ,Rats, Sprague-Dawley ,03 medical and health sciences ,0302 clinical medicine ,Intestinal mucosa ,medicine ,Animals ,Humans ,Intestinal Mucosa ,Progenitor cell ,Induced pluripotent stem cell ,lcsh:Science ,Cells, Cultured ,Cell Proliferation ,Multidisciplinary ,Tissue Engineering ,Tissue Scaffolds ,business.industry ,Fatty Acids ,Endothelial Cells ,Cell Differentiation ,General Chemistry ,Intestinal epithelium ,Epithelium ,Small intestine ,Rats ,3. Good health ,Intestines ,Transplantation ,Glucose ,030104 developmental biology ,medicine.anatomical_structure ,surgical procedures, operative ,030220 oncology & carcinogenesis ,lcsh:Q ,business - Abstract
Patients with short bowel syndrome lack sufficient functional intestine to sustain themselves with enteral intake alone. Transplantable vascularized bioengineered intestine could restore nutrient absorption. Here we report the engineering of humanized intestinal grafts by repopulating decellularized rat intestinal matrix with human induced pluripotent stem cell-derived intestinal epithelium and human endothelium. After 28 days of in vitro culture, hiPSC-derived progenitor cells differentiate into a monolayer of polarized intestinal epithelium. Human endothelial cells seeded via native vasculature restore perfusability. Ex vivo isolated perfusion testing confirms transfer of glucose and medium-chain fatty acids from lumen to venous effluent. Four weeks after transplantation to RNU rats, grafts show survival and maturation of regenerated epithelium. Systemic venous sampling and positron emission tomography confirm uptake of glucose and fatty acids in vivo. Bioengineering intestine on vascularized native scaffolds could bridge the gap between cell/tissue-scale regeneration and whole organ-scale technology needed to treat intestinal failure patients., There is a need for humanised grafts to treat patients with intestinal failure. Here, the authors generate intestinal grafts by recellularizing native intestinal matrix with human induced pluripotent stem cell-derived epithelium and human endothelium, and show nutrient absorption after transplantation in rats.
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- 2017
8. Biofabrication of a vascularized islet organ for type 1 diabetes
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Taufiek Konrad Rajab, Daniele Evangelista-Leite, Andrea Peloso, Philipp T. Moser, Silvia Pellegrini, Erica Dugnani, Fabio Manenti, Xi Ren, Antonio Citro, Harald C. Ott, Jonathan M. Charest, Lorenzo Piemonti, Bruno K. Podesser, Citro, Antonio, Moser, Philipp T., Dugnani, Erica, Rajab, Konrad T., Ren, Xi, Evangelista-Leite, Daniele, Charest, Jonathan M., Peloso, Andrea, Podesser, Bruno K., Manenti, Fabio, Pellegrini, Silvia, Piemonti, Lorenzo, and Ott, Harald C.
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Male ,endocrine system ,Pathology ,medicine.medical_specialty ,endocrine system diseases ,Type 1 diabete ,medicine.medical_treatment ,Biophysics ,Endocrine System ,Bioengineering ,Ceramics and Composite ,02 engineering and technology ,Biomaterials ,Islets of Langerhans ,03 medical and health sciences ,Tissue engineering ,In vivo ,medicine ,Animals ,Humans ,Islet transplantation ,Decellularization ,030304 developmental biology ,0303 health sciences ,geography ,geography.geographical_feature_category ,Tissue Engineering ,business.industry ,Insulin ,Alternative site ,Extracellular matrix ,021001 nanoscience & nanotechnology ,Islet ,Biomaterial ,Mice, Inbred C57BL ,Transplantation ,Diabetes Mellitus, Type 1 ,surgical procedures, operative ,Biophysic ,Rats, Inbred Lew ,Mechanics of Materials ,Ceramics and Composites ,Stem cell ,0210 nano-technology ,business ,Lung scaffold ,Ex vivo - Abstract
Islet transplantation is superior to extrinsic insulin supplementation in the treating severe Type 1 diabetes. However, its efficiency and longevity are limited by substantial islet loss post-transplantation due to lack of engraftment and vascular supply. To overcome these limitations, we developed a novel approach to bio-fabricate functional, vascularized islet organs (VIOs) ex vivo. We endothelialized acellular lung matrixes to provide a biocompatible multicompartment scaffold with an intact hierarchical vascular tree as a backbone for islet engraftment. Over seven days of culture, islets anatomically and functionally integrated into the surrounding bio-engineered vasculature, generating a functional perfusable endocrine organ. When exposed to supra-physiologic arterial glucose levels in vivo and ex vivo, mature VIOs responded with a physiologic insulin release from the vein and provided more efficient reduction of hyperglycemia compared to intraportally transplanted fresh islets. In long-term transplants in diabetic mice, subcutaneously implanted VIOs achieved normoglycemia significantly faster and more efficiently compared to islets that were transplanted in deviceless fashion. We conclude that ex vivo bio-fabrication of VIOs enables islet engraftment and vascularization before transplantation, and thereby helps to overcome limited islet survival and function observed in conventional islet transplantation. Given recent progress in stem cells, this technology may enable assembly of functional personalized endocrine organs.
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- 2019
9. A Fully Automated High-Throughput Bioreactor System for Lung Regeneration
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Harald C. Ott, Sarah E. Gilpin, Daniel Gorman, and Tong Wu
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0301 basic medicine ,Male ,Biomedical Engineering ,Medicine (miscellaneous) ,Bioengineering ,Biology ,Rats, Sprague-Dawley ,03 medical and health sciences ,Automation ,Bioreactors ,Organ Culture Techniques ,Bioreactor ,medicine ,Animals ,Regeneration ,Throughput (business) ,Lung ,Cell Proliferation ,Tissue Engineering ,Tissue Scaffolds ,Regeneration (biology) ,Cadaveric donor ,Endothelial Cells ,Epithelial Cells ,respiratory system ,respiratory tract diseases ,Rats ,Methods Articles ,Lung repair ,030104 developmental biology ,medicine.anatomical_structure ,Fully automated ,Ex vivo ,Biomedical engineering - Abstract
The careful study of cell-based lung repair and regeneration ex vivo may one day provide us with the necessary tools to create a patient-derived alternative to cadaveric donor lungs for transplantation. Many parameters must be monitored and optimized to advance this aim. The use of rat lungs as a small-scale model for lung regeneration is an efficient way to develop the key improvements required for optimal tissue repair and regeneration. In this study, we report the use of a novel high-throughput, automated, multichannel lung bioreactor system, which allows for culture and analysis of rodent scale isolated lungs. In this model, five decellularized rat lungs can be repopulated with human primary endothelial and epithelial cells, cultured under varying perfusion and ventilation parameters in parallel, and analyzed for standardized endpoints. As a proof of principle, we report a multiphase organ culture protocol, which achieves consistent tissue regeneration across lungs at multiple points during culture, and further promotes overall tissue maturation through the application of lung ventilation. IMPACT STATEMENT: This work presents methods for ex vivo lung recellularization and biomimetic culture in a high-throughput and consistent manner. These methods allow for the testing of multiple variables, all of which are simultaneously controlled and monitored on a single fully automated pump system, and subsequent assessment of both epithelial and endothelial repair and tissue regeneration. This system provides a controlled environment for tissue repair, wherein key variables can be modified, monitored, reproduced, and optimized to advance the goal of ex vivo tissue regeneration based on native organ scaffolds.
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- 2018
10. Proteomic analysis of naturally-sourced biological scaffolds
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Sharon Geerts, Brian L. Frey, Sarah E. Gilpin, Martin L. Yarmush, Basak E. Uygun, Harald C. Ott, Nathan V. Welham, Qiyao Li, Mark Scalf, Lloyd M. Smith, and Sinan Ozer
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Proteomics ,0301 basic medicine ,Scaffold ,Blotting, Western ,Biophysics ,Bioengineering ,Matrix (biology) ,Biology ,Bioinformatics ,Article ,Collagen Type I ,Biomaterials ,Extracellular matrix ,03 medical and health sciences ,Tissue engineering ,Animals ,Humans ,Lung ,Matrigel ,Decellularization ,Tissue Scaffolds ,Cell growth ,DNA ,Cell biology ,Drug Combinations ,030104 developmental biology ,Liver ,Rats, Inbred Lew ,Mechanics of Materials ,Ceramics and Composites ,Intercellular Signaling Peptides and Proteins ,Female ,Proteoglycans ,Collagen ,Laminin - Abstract
A key challenge to the clinical implementation of decellularized scaffold-based tissue engineering lies in understanding the process of removing cells and immunogenic material from a donor tissue/organ while maintaining the biochemical and biophysical properties of the scaffold that will promote growth of newly seeded cells. Current criteria for evaluating whole organ decellularization are primarily based on nucleic acids, as they are easy to quantify and have been directly correlated to adverse host responses. However, numerous proteins cause immunogenic responses and thus should be measured directly to further understand and quantify the efficacy of decellularization. In addition, there has been increasing appreciation for the role of the various protein components of the extracellular matrix (ECM) in directing cell growth and regulating organ function. We performed in-depth proteomic analysis on four types of biological scaffolds and identified a large number of both remnant cellular and ECM proteins. Measurements of individual protein abundances during the decellularization process revealed significant removal of numerous cellular proteins, but preservation of most structural matrix proteins. The observation that decellularized scaffolds still contain many cellular proteins, although at decreased abundance, indicates that elimination of DNA does not assure adequate removal of all cellular material. Thus, proteomic analysis provides crucial characterization of the decellularization process to create biological scaffolds for future tissue/organ replacement therapies.
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- 2016
11. Can We Re-Engineer the Endocrine Pancreas?
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Antonio Citro and Harald C. Ott
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0301 basic medicine ,Endocrinology, Diabetes and Metabolism ,Enteroendocrine cell ,Extracellular matrix ,Islets of Langerhans ,03 medical and health sciences ,0302 clinical medicine ,Tissue engineering ,Insulin-Secreting Cells ,Internal Medicine ,Animals ,Humans ,Medicine ,Endocrine system ,geography ,geography.geographical_feature_category ,Decellularization ,Tissue Engineering ,business.industry ,Islet ,Embryonic stem cell ,Extracellular Matrix ,Cell biology ,030104 developmental biology ,medicine.anatomical_structure ,business ,Pancreas ,030217 neurology & neurosurgery - Abstract
Engineering endocrine pancreatic tissue is an emerging topic in type 1 diabetes with the intent to overcome the current limitation of β cell transplantation. During islet isolation, the vascularized structure and surrounding extracellular matrix (ECM) are completely disrupted. Once implanted, islets slowly engraft and mostly are lost for the initial avascular phase. This review discusses the main building blocks required to engineer the endocrine pancreas: (i) islet niche ECM, (ii) islet niche vascular network, and (iii) new available sources of endocrine cells. Current approaches include the following: tissue engineering of endocrine grafts by seeding of native or synthetic ECM scaffolds with human islets, vascularization of native or synthetic ECM prior to implantation, vascular functionalization of ECM structures to enhance angiogenesis after implantation, generation of engineered animals as human organ donors, and embryonic and pluripotent stem cell-derived endocrine cells that may be encapsulated or genetically engineered to be immunotolerated. Substantial technological improvements have been made to regenerate or engineer endocrine pancreatic tissue; however, significant hurdles remain, and more research is needed to develop a technology to integrate all components of viable endocrine tissue for clinical application.
- Published
- 2018
12. Ex Vivo Modeling of Perioperative Air Leaks in Porcine Lungs
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Charles, Klassen, Chad E, Eckert, Jordan, Wong, Jacques P, Guyette, Jason L, Harris, Suzanne, Thompson, Leonard J, Wudel, and Harald C, Ott
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Postoperative Complications ,Swine ,Air ,Electric Impedance ,Animals ,Signal Processing, Computer-Assisted ,Perioperative Period ,Lung ,Models, Biological ,Respiration, Artificial ,Tomography - Abstract
A novel ex vivo model is described to advance the understanding of prolonged air leaks, one of the most common postoperative complications following thoracic resection procedures.As an alternative to in vivo testing, an ex vivo model simulating the various physiologic environments experienced by an isolated lung during the perioperative period was designed and built. Isolated porcine lungs were perfused and ventilated during open chest and closed chest simulations, mimicking intra and postoperative ventilation conditions. To assess and validate system capabilities, nine porcine lungs were tested by creating a standardized injury to create an approximately 250 cc/min air leak. Air leak rates, physiologic ventilation, and perfusion parameters were continuously monitored, while gas transfer analysis was performed on selected lungs. Segmental ventilation was monitored using electrical impedance tomography.The evaluated lungs produced flow-volume and pressure-volume loops that approximated standard clinical representations under positive (mechanical) and negative (physiological) pressure ventilation modalities. Leak rate was averaged across the ventilation phases, and sharp increases in leak rate were observed between positive and negative pressure phases, suggesting that differences or changes in ventilation mechanics may strongly influence leak development.The successful design and validation of a novel ex vivo lung model was achieved. Model output paralleled clinical observations. Pressure modality may also play a significant role in air leak severity.This work provides a foundation for future studies aimed at increasing the understanding of air leaks to better inform means of mitigating the risk of air leaks under clinically relevant conditions.
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- 2018
13. Direct Reprogramming of Mouse Fibroblasts into Functional Skeletal Muscle Progenitors
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Konrad Hochedlinger, Priscilla Cheung, Amy Coffey, A. Almada, Sylvain Paisant, Duygu Payzin-Dogru, Mattia F. M. Gerli, Harald C. Ott, Aaron J. Huebner, Amy Galvin, Anthony Anselmo, Ori Bar-Nur, Amy J. Wagers, Bruno Di Stefano, Shahragim Tajbakhsh, Michael A. Rudnicki, Peter Feige, Cassandra Verheul, and Ruslan I. Sadreyev
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0301 basic medicine ,Skeletal muscle ,Satellite cells ,Direct lineage reprogramming ,Induced muscle progenitor cells ,MyoD ,Pax7 ,Small molecules ,Transplantation ,Muscular dystrophy ,Muscle Fibers, Skeletal ,Muscle Development ,Biochemistry ,Mice ,Myocyte ,Transgenes ,Cell Self Renewal ,Stem Cell Niche ,lcsh:QH301-705.5 ,lcsh:R5-920 ,Stem Cells ,PAX7 Transcription Factor ,Cell Differentiation ,musculoskeletal system ,Cellular Reprogramming ,Cell biology ,medicine.anatomical_structure ,MYF5 ,Stem cell ,lcsh:Medicine (General) ,tissues ,Reprogramming ,Cell type ,Satellite Cells, Skeletal Muscle ,Biology ,Article ,Small Molecule Libraries ,03 medical and health sciences ,Genetics ,medicine ,Animals ,Regeneration ,Progenitor cell ,Muscle, Skeletal ,MyoD Protein ,Cell Biology ,Fibroblasts ,Muscular Dystrophy, Animal ,030104 developmental biology ,lcsh:Biology (General) ,Biomarkers ,Developmental Biology ,Stem Cell Transplantation - Abstract
Summary Skeletal muscle harbors quiescent stem cells termed satellite cells and proliferative progenitors termed myoblasts, which play pivotal roles during muscle regeneration. However, current technology does not allow permanent capture of these cell populations in vitro. Here, we show that ectopic expression of the myogenic transcription factor MyoD, combined with exposure to small molecules, reprograms mouse fibroblasts into expandable induced myogenic progenitor cells (iMPCs). iMPCs express key skeletal muscle stem and progenitor cell markers including Pax7 and Myf5 and give rise to dystrophin-expressing myofibers upon transplantation in vivo. Notably, a subset of transplanted iMPCs maintain Pax7 expression and sustain serial regenerative responses. Similar to satellite cells, iMPCs originate from Pax7+ cells and require Pax7 itself for maintenance. Finally, we show that myogenic progenitor cell lines can be established from muscle tissue following small-molecule exposure alone. This study thus reports on a robust approach to derive expandable myogenic stem/progenitor-like cells from multiple cell types., Graphical Abstract, Highlights • MyoD and small molecules reprogram fibroblasts to myogenic progenitors termed iMPCs • iMPCs self-renew and express key satellite cell and myoblast markers • iMPC growth is driven by Pax7+ cells and requires Pax7 gene function • Transplanted iMPCs engraft and sustain muscle regeneration in vivo, In this article, Hochedlinger and colleagues reprogrammed mouse fibroblasts into induced myogenic progenitors (iMPCs) by transient expression of MyoD and treatment with small molecules. iMPCs can be extensively propagated in vitro and exhibit skeletal muscle stem/progenitor cell characteristics, including the requirement for Pax7 function as well as the ability to sustain muscle regeneration upon repeated injury.
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- 2018
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14. Perfusion decellularization of a human limb: A novel platform for composite tissue engineering and reconstructive surgery
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Brian B. Ghoshhajra, Jacques P. Guyette, Mattia F. M. Gerli, Harald C. Ott, and Daniele Evangelista-Leite
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0301 basic medicine ,Male ,Scaffold ,X-ray microtomography ,Biopsy ,Surfactants ,lcsh:Medicine ,Biochemistry ,Diagnostic Radiology ,Extracellular matrix ,Bioreactors ,Medicine and Health Sciences ,lcsh:Science ,Tomography ,Staining ,Multidisciplinary ,Decellularization ,medicine.diagnostic_test ,Tissue Scaffolds ,Radiology and Imaging ,Soft tissue ,Middle Aged ,Extracellular Matrix ,Perfusion ,medicine.anatomical_structure ,Physical Sciences ,Arm ,Cellular Structures and Organelles ,Anatomy ,Plastic Surgery and Reconstructive Techniques ,Research Article ,Muscle tissue ,Imaging Techniques ,Materials Science ,Detergents ,Muscle Tissue ,Surgical and Invasive Medical Procedures ,Neuroimaging ,Research and Analysis Methods ,03 medical and health sciences ,Imaging, Three-Dimensional ,Diagnostic Medicine ,medicine ,Cadaver ,Animals ,Humans ,Materials by Attribute ,Tissue Engineering ,lcsh:R ,Biology and Life Sciences ,Proteins ,Cell Biology ,X-Ray Microtomography ,Plastic Surgery Procedures ,Computed Axial Tomography ,Rats ,Nuclear Staining ,030104 developmental biology ,Biological Tissue ,Specimen Preparation and Treatment ,lcsh:Q ,Collagens ,Biomedical engineering ,Neuroscience - Abstract
Muscle and fasciocutaneous flaps taken from autologous donor sites are currently the most utilized approach for trauma repair, accounting annually for 4.5 million procedures in the US alone. However, the donor tissue size is limited and the complications related to these surgical techniques lead to morbidities, often involving the donor sites. Alternatively, recent reports indicated that extracellular matrix (ECM) scaffolds boost the regenerative potential of the injured site, as shown in a small cohort of volumetric muscle loss patients. Perfusion decellularization is a bioengineering technology that allows the generation of clinical-scale ECM scaffolds with preserved complex architecture and with an intact vascular template, from a variety of donor organs and tissues. We recently reported that this technology is amenable to generate full composite tissue scaffolds from rat and non-human primate limbs. Translating this platform to human extremities could substantially benefit soft tissue and volumetric muscle loss patients providing tissue- and species-specific grafts. In this proof-of-concept study, we show the successful generation a large-scale, acellular composite tissue scaffold from a full cadaveric human upper extremity. This construct retained its morphological architecture and perfusable vascular conduits. Histological and biochemical validation confirmed the successful removal of nuclear and cellular components, and highlighted the preservation of the native extracellular matrix components. Our results indicate that perfusion decellularization can be applied to produce human composite tissue acellular scaffolds. With its preserved structure and vascular template, these biocompatible constructs, could have significant advantages over the currently implanted matrices by means of nutrient distribution, size-scalability and immunological response.
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- 2018
15. Engineering pulmonary vasculature in decellularized rat and human lungs
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David T. Scadden, Tatsuya Okamoto, Francois Mercier, Philipp T. Moser, Sarah E. Gilpin, Harald C. Ott, Douglas J. Mathisen, Linjie Xiong, Raja Ghawi, Tong Wu, Luis F. Tapias, and Xi Ren
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Male ,Pathology ,medicine.medical_specialty ,Endothelium ,Biomedical Engineering ,Neovascularization, Physiologic ,Bioengineering ,Pulmonary Artery ,Applied Microbiology and Biotechnology ,Rats, Sprague-Dawley ,Species Specificity ,Tissue engineering ,medicine ,Animals ,Humans ,Regeneration ,Viability assay ,Induced pluripotent stem cell ,Lung ,Cells, Cultured ,Decellularization ,Cell-Free System ,Tissue Engineering ,Tissue Scaffolds ,business.industry ,Regeneration (biology) ,Endothelial Cells ,Equipment Design ,Anatomy ,Rats ,Equipment Failure Analysis ,Transplantation ,medicine.anatomical_structure ,Molecular Medicine ,business ,Biotechnology - Abstract
Bioengineered lungs produced from patient-derived cells may one day provide an alternative to donor lungs for transplantation therapy. Here we report the regeneration of functional pulmonary vasculature by repopulating the vascular compartment of decellularized rat and human lung scaffolds with human cells, including endothelial and perivascular cells derived from induced pluripotent stem cells. We describe improved methods for delivering cells into the lung scaffold and for maturing newly formed endothelium through co-seeding of endothelial and perivascular cells and a two-phase culture protocol. Using these methods we achieved ∼75% endothelial coverage in the rat lung scaffold relative to that of native lung. The regenerated endothelium showed reduced vascular resistance and improved barrier function over the course of in vitro culture and remained patent for 3 days after orthotopic transplantation in rats. Finally, we scaled our approach to the human lung lobe and achieved efficient cell delivery, maintenance of cell viability and establishment of perfusable vascular lumens.
- Published
- 2015
16. Spray Delivery of Intestinal Organoids to Reconstitute Epithelium on Decellularized Native Extracellular Matrix
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Harald C. Ott, Allan M. Goldstein, Adam K. Ekenseair, Dana M. Schwartz, and Meryem O. Pehlivaner Kara
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0301 basic medicine ,Male ,Scaffold ,Cell type ,Cell Survival ,Biomedical Engineering ,Medicine (miscellaneous) ,Bioengineering ,Epithelium ,Extracellular matrix ,Rats, Sprague-Dawley ,03 medical and health sciences ,Mice ,0302 clinical medicine ,Tissue engineering ,Organoid ,medicine ,Animals ,Humans ,Viability assay ,Intestinal Mucosa ,Decellularization ,Tissue Engineering ,Tissue Scaffolds ,Chemistry ,Cell biology ,Extracellular Matrix ,Methods Articles ,Organoids ,030104 developmental biology ,medicine.anatomical_structure ,Microscopy, Fluorescence ,030220 oncology & carcinogenesis ,Caco-2 Cells ,Biomedical engineering - Abstract
The native extracellular matrix (ECM) serves as a unique platform for tissue engineering because it provides an organ-specific scaffold in terms of both matrix composition and tissue architecture. However, efficacious cell-seeding techniques for recellularizing the ECM constructs with appropriate cell types to restore biological function remain under development. In this study, the impact of spraying as a seeding technique for repopulation of decellularized small intestine was investigated. In a series of experiments, CaCo-2 cells were first used to investigate the effect of spray device type and pressure on cell viability and to optimize parameters for seeding intestinal epithelial cells. High cell viability and a homogeneous cell distribution were obtained when cell suspensions were sprayed through an airbrush at low pressure. Next, the effect of seeding method and spray pressure on the size and dispersal of intestinal organoids, a more complex and clinically relevant intestinal stem cell population, was evaluated. The feasibility of seeding intestinal epithelial cells onto decellularized scaffolds was next studied using sprayed CaCo-2 cells, which survived the spray-seeding process and formed a monolayer on the scaffold. Finally, airbrush seeding was used to spray intestinal organoids onto the scaffolds, with cell survival and tissue architecture evaluated after 1 week of culture. Organoids seeded through pipetting onto the decellularized scaffold survived, but demonstrated aggregation, with cells organized around multiple small lumens. In contrast, organoids airbrush spray seeded at 0.35 bar onto the decellularized scaffold not only engrafted but also demonstrated formation of an epithelial monolayer that resembled the absorptive surface found on intestinal villi. The results suggest that seeding cells through airbrush spraying holds great potential for use in tissue engineering, especially for large-scale tubular organ recellularization.
- Published
- 2017
17. Creation of a Bioengineered Skin Flap Scaffold with a Perfusable Vascular Pedicle
- Author
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Emilia Javorsky, Bernhard J. Jank, Joshua R. Gershlak, Jeremy Goverman, Curtis L. Cetrulo, William G. Austen, Harald C. Ott, Jon M Charest, Rosalynn M. Nazarian, Jacques P. Guyette, Martin Purschke, Glenn R. Gaudette, Mark A. Randolph, and David A. Leonard
- Subjects
0301 basic medicine ,Scaffold ,Swine ,medicine.medical_treatment ,Biomedical Engineering ,Bioengineering ,Biochemistry ,Surgical Flaps ,Biomaterials ,Extracellular matrix ,Neovascularization ,Rats, Sprague-Dawley ,03 medical and health sciences ,In vivo ,Materials Testing ,medicine ,Animals ,Skin ,Decellularization ,integumentary system ,Tissue Scaffolds ,business.industry ,Regeneration (biology) ,Original Articles ,Rats ,030104 developmental biology ,Skin grafting ,Swine, Miniature ,medicine.symptom ,Wound healing ,business ,Biomedical engineering - Abstract
Full-thickness skin loss is a challenging problem due to limited reconstructive options, demanding 75 million surgical procedures annually in the United States. Autologous skin grafting is the gold standard treatment, but results in donor-site morbidity and poor aesthetics. Numerous skin substitutes are available on the market to date, however, none truly functions as full-thickness skin due to lack of a vascular network. The creation of an autologous full-thickness skin analogue with a vascular pedicle would result in a paradigm shift in the management of wounds and in reconstruction of full-thickness skin defects. To create a clinically relevant foundation, we generated an acellular skin flap scaffold (SFS) with a perfusable vascular pedicle of clinically relevant size by perfusion decellularization of porcine fasciocutaneous flaps. We then analyzed the yielded SFS for mechanical properties, biocompatibility, and regenerative potential in vitro and in vivo. Furthermore, we assessed the immunological response using an in vivo model. Finally, we recellularized the vascular compartment of an SFS and reconnected it to a recipient's blood supply to test for perfusability. Perfusion decellularization removed all cellular components with preservation of native extracellular matrix composition and architecture. Biaxial testing revealed preserved mechanical properties. Immunologic response and biocompatibility assessed via implantation and compared with native xenogenic skin and commercially available dermal substitutes revealed rapid neovascularization and complete tissue integration. Composition of infiltrating immune cells showed no evidence of allorejection and resembled the inflammatory phase of wound healing. Implantation into full-thickness skin defects demonstrated good tissue integration and skin regeneration without cicatrization. We have developed a protocol for the generation of an SFS of clinically relevant size, containing a vascular pedicle, which can be utilized for perfusion decellularization and, ultimately, anastomosis to the recipient vascular system after precellularization. The observed favorable immunological response and good tissue integration indicate the substantial regenerative potential of this platform.
- Published
- 2017
18. Bioengineering Human Lung Grafts on Porcine Matrix
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Lauren D. Black, Tong Wu, Harald C. Ott, Lauren Baugh, Douglas J. Mathisen, Taufiek Konrad Rajab, Haiyang Zhou, Min Wu, Xi Ren, Sarah E. Gilpin, and Kentaro Kitano
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0301 basic medicine ,medicine.medical_specialty ,Tissue Scaffolds ,business.industry ,Swine ,Background data ,Endothelial Cells ,Bioengineering ,Epithelial Cells ,Human lung ,Surgery ,03 medical and health sciences ,surgical procedures, operative ,030104 developmental biology ,0302 clinical medicine ,medicine.anatomical_structure ,Transplant surgery ,030228 respiratory system ,medicine ,Animals ,Humans ,business ,Bioartificial Organ ,Lung Transplantation - Abstract
Bioengineering of viable, functional, and implantable human lung grafts on porcine matrix.Implantable bioartificial organ grafts could revolutionize transplant surgery. To date, several milestones toward that goal have been achieved in rodent models. To make bioengineered organ grafts clinically relevant, scaling to human cells and graft size are the next steps.We seeded porcine decellularized lung scaffolds with human airway epithelial progenitor cells derived from rejected donor lungs, and banked human umbilical vein endothelial cells. We subsequently enabled tissue formation in whole organ culture. The resulting grafts were then either analyzed in vitro (n = 15) or transplanted into porcine recipients in vivo (n = 3).By repopulating porcine extracellular matrix scaffolds with human endothelial cells, we generated pulmonary vasculature with mature endothelial lining and sufficient anti-thrombotic function to enable blood perfusion. By repopulating the epithelial surface with human epithelial progenitor cells, we created a living, functioning gas exchange graft. After surgical implantation, the bioengineered lung grafts were able to withstand physiological blood flow from the recipient's pulmonary circulation, and exchanged gases upon ventilation during the 1-hour observation.Engineering and transplantation of viable lung grafts based on decellularized porcine lung scaffolds and human endothelial and epithelial cells is technically feasible. Further graft maturation will be necessary to enable higher-level functions such as mucociliary clearance, and ventilation-perfusion matching.
- Published
- 2017
19. On the road to bioartificial organs
- Author
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Harald C. Ott and Xi Ren
- Subjects
Organ engineering ,Decellularization ,Bioartificial Organs ,Tissue Engineering ,Physiology ,business.industry ,Clinical Biochemistry ,Bioprinting ,Economic shortage ,Computational biology ,Human physiology ,Biology ,Organ culture ,Biotechnology ,Transplantation ,Tissue engineering ,Physiology (medical) ,Animals ,Humans ,business ,Bioartificial Organ - Abstract
Biological organs are highly orchestrated systems with well-coordinated positioning, grouping, and interaction of different cell types within their specialized extracellular environment. Bioartificial organs are intended to be functional replacements of native organs generated through bioengineering techniques and hold the potential to alleviate donor organ shortage for transplantation. The development, production, and evaluation of such bioartificial organs require synergistic efforts of biology, material science, engineering, and medicine. In this review, we highlight the emerging platforms enabling structured assembly of multiple cell types into functional grafts and discuss recent advances and challenges in the development of bioartificial organs, including cell sources, in vitro organ culture, in vivo evaluation, and clinical considerations.
- Published
- 2014
20. Perfusion decellularization of human and porcine lungs: Bringing the matrix to clinical scale
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John M. Asara, Xi Ren, Sarah E. Gilpin, Harald C. Ott, Gabriel Gonzalez, Douglas J. Mathisen, Joseph P. Vacanti, and Jacques P. Guyette
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Pulmonary and Respiratory Medicine ,Swine ,medicine.medical_treatment ,Detergents ,Biocompatible Materials ,Bioengineering ,Matrix (biology) ,Umbilical vein ,Rats, Sprague-Dawley ,Glycosaminoglycan ,Extracellular matrix ,chemistry.chemical_compound ,medicine ,Animals ,Humans ,Sodium dodecyl sulfate ,Lung ,Cells, Cultured ,Transplantation ,Decellularization ,Dose-Response Relationship, Drug ,Tissue Scaffolds ,biology ,business.industry ,Sodium Dodecyl Sulfate ,Cholic Acids ,Epithelial Cells ,Anatomy ,Extracellular Matrix ,Rats ,Cell biology ,Perfusion ,chemistry ,Models, Animal ,biology.protein ,Surgery ,Endothelium, Vascular ,Cardiology and Cardiovascular Medicine ,business ,Elastin ,Deoxycholic Acid ,Allotransplantation - Abstract
Background Organ engineering is a theoretical alternative to allotransplantation for end-stage organ failure. Whole-organ scaffolds can be created by detergent perfusion via the native vasculature, generating an acellular matrix suitable for recellularization with selected cell types. We aimed to up-scale this process, generating biocompatible scaffolds of a clinically relevant scale. Methods Rat, porcine, and human lungs were decellularized by detergent perfusion at constant pressures. Collagen, elastin, and glycosaminoglycan content of scaffolds were quantified by colorimetric assays. Proteomic analysis was performed by microcapillary liquid chromatography tandem mass spectrometry. Extracellular matrix (ECM) slices were cultured with human umbilical vein endothelial cells (HUVEC), small airway epithelial cells (SAEC), or pulmonary alveolar epithelial cells (PAECs) and evaluated by time-lapse live cell microscopy and MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay. Whole-organ culture was maintained under constant-pressure media perfusion after seeding with PAECs. Results Rat lungs were decellularized using: (1) sodium dodecyl sulfate (SDS), (2) sodium deoxycholate (SDC), or (3) 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate (CHAPS). Resulting scaffolds showed comparable loss of DNA but greatest preservation of ECM components in SDS-decellularized lungs. Porcine ( n = 10) and human ( n = 7) lungs required increased SDS concentration, perfusion pressures, and time to achieve decellularization as determined by loss of DNA, with preservation of intact matrix composition and lung architecture. Proteomic analysis of human decellularized lungs further confirmed ECM preservation. Recellularization experiments confirmed scaffold biocompatibility when cultured with mature cell phenotypes and scaffold integrity for the duration of biomimetic culture. Conclusions SDS-based perfusion decellularization can be applied to whole porcine and human lungs to generate biocompatible organ scaffolds with preserved ECM composition and architecture.
- Published
- 2014
21. Intralipid improves oxygenation after orthotopic rat lung transplantation
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Harald C. Ott, Douglas J. Mathisen, Tatsuya Okamoto, Xi Ren, and Taufiek Konrad Rajab
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Pulmonary and Respiratory Medicine ,Graft Rejection ,Male ,Fat Emulsions, Intravenous ,medicine.medical_treatment ,Rats, Sprague-Dawley ,Medicine ,Lung transplantation ,Animals ,Lung ,Phospholipids ,Transplantation ,business.industry ,Oxygenation ,Rats ,Soybean Oil ,Oxygen ,Disease Models, Animal ,Rats, Inbred Lew ,Anesthesia ,Reperfusion Injury ,Surgery ,Emulsions ,Cardiology and Cardiovascular Medicine ,business ,Lung Transplantation - Published
- 2016
22. Regeneration and experimental orthotopic transplantation of a bioengineered kidney
- Author
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Jeremy Song, Gabriel Gonzalez, Sarah E. Gilpin, Joseph P. Vacanti, Jacques P. Guyette, and Harald C. Ott
- Subjects
Male ,medicine.medical_specialty ,Pathology ,Swine ,medicine.medical_treatment ,Biomedical Engineering ,Renal function ,02 engineering and technology ,Kidney ,Artificial kidney ,General Biochemistry, Genetics and Molecular Biology ,Rats, Sprague-Dawley ,03 medical and health sciences ,Bioreactors ,Human Umbilical Vein Endothelial Cells ,medicine ,Animals ,Humans ,Kidney transplantation ,030304 developmental biology ,0303 health sciences ,Decellularization ,Tissue Engineering ,Tissue Scaffolds ,business.industry ,Endothelial Cells ,Epithelial Cells ,Immunosuppression ,General Medicine ,021001 nanoscience & nanotechnology ,medicine.disease ,Kidney Transplantation ,6. Clean water ,Rats ,Surgery ,Perfusion ,surgical procedures, operative ,medicine.anatomical_structure ,Renal physiology ,0210 nano-technology ,business ,Kidney disease - Abstract
Approximately 100,000 individuals in the United States currently await kidney transplantation, and 400,000 individuals live with end-stage kidney disease requiring hemodialysis. The creation of a transplantable graft to permanently replace kidney function would address donor organ shortage and the morbidity associated with immunosuppression. Such a bioengineered graft must have the kidney's architecture and function and permit perfusion, filtration, secretion, absorption and drainage of urine. We decellularized rat, porcine and human kidneys by detergent perfusion, yielding acellular scaffolds with vascular, cortical and medullary architecture, a collecting system and ureters. To regenerate functional tissue, we seeded rat kidney scaffolds with epithelial and endothelial cells and perfused these cell-seeded constructs in a whole-organ bioreactor. The resulting grafts produced rudimentary urine in vitro when perfused through their intrinsic vascular bed. When transplanted in an orthotopic position in rat, the grafts were perfused by the recipient's circulation and produced urine through the ureteral conduit in vivo.
- Published
- 2013
23. Multipotent Mesenchymal Stem Cells Acquire a Lymphendothelial Phenotype and Enhance Lymphatic Regeneration In Vivo
- Author
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Christiane J. Bruns, Claudius Conrad, Harald C. Ott, Stephan Huber, Irene von Luettichau, Peter J. Nelson, Ralf Huss, Hanno Niess, and Karl-Walter Jauch
- Subjects
Lymphatic edema ,Pathology ,medicine.medical_specialty ,Endothelium ,government.form_of_government ,Biology ,Cell Line ,Mice ,chemistry.chemical_compound ,Cell Movement ,Physiology (medical) ,medicine ,Animals ,Humans ,Regeneration ,Lymphangiogenesis ,Lymphatic Vessels ,Mice, Inbred BALB C ,Multipotent Stem Cells ,Mesenchymal stem cell ,Cell Differentiation ,Mesenchymal Stem Cells ,Mice, Inbred C57BL ,Vascular endothelial growth factor ,Lymphatic Endothelium ,Phenotype ,Lymphatic system ,medicine.anatomical_structure ,chemistry ,government ,Cancer research ,Female ,Endothelium, Lymphatic ,Stem cell ,Cardiology and Cardiovascular Medicine - Abstract
Background— The importance and therapeutic value of stem cells in lymphangiogenesis are poorly understood. We evaluated the potential of human and murine mesenchymal stem cells (MSCs) to acquire a lymphatic phenotype in vitro and to enhance lymphatic regeneration in vivo. Methods and Results— We assessed the lymphendothelial differentiation of human and murine MSCs after induction with supernatant derived from human dermal microvascular endothelial cells, isolated lymphatic endothelial cells, and purified vascular endothelial growth factor (VEGF)-C in vitro. We used human or murine progenitor MSC lines and then characterized the lymphatic phenotype by morphology, migratory capacity, and the expression of lymphatic markers such as Prox-1, podoplanin, Lyve-1, VEGF receptor-2, and VEGF receptor-3. Using a murine lymphatic edema model, we assessed the potential of these cells to form a functional lymphatic vasculature in vivo after injection of syngeneic MSCs. Incubation with supernatant from lymphatic endothelial cells induced an endothelium-like morphology and the expression of lymphendothelial markers in both human and murine MSCs in vitro. MSCs showed migratory activity along a VEGF-C gradient, which was enhanced by VEGF-C conditioning. In vivo, the local application of MSCs resulted in a significant decrease in edema formation (−20.1%; P Conclusions— MSCs were capable of expressing a lymphatic phenotype when exposed to lymph-inductive media and purified VEGF-C. Migratory activity toward VEGF-C in vitro suggests homing capability in vivo. Restoration of lymphatic drainage after injection of MSCs in a lymphedema model indicates that MSCs play a role in lymphatic regeneration. The potential clinical application of MSC in wound healing and reduction of lymphatic edema warrants further research.
- Published
- 2009
24. Sex-Dependent Attenuation of Plaque Growth After Treatment With Bone Marrow Mononuclear Cells
- Author
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Harald C. Ott, Craig Stolen, Wendy Nelson, Xiangrong Xin, Angela Panoskaltsis-Mortari, Andrey G. Zenovich, Doris A. Taylor, Gabriel J. Caron, and Samuel A. Barnes
- Subjects
Male ,Apolipoprotein E ,medicine.medical_specialty ,Pathology ,Apolipoprotein B ,Physiology ,medicine.medical_treatment ,CD34 ,Coronary Artery Disease ,Granulocyte ,Peripheral blood mononuclear cell ,Mice ,Apolipoproteins E ,Internal medicine ,medicine ,Animals ,Progenitor cell ,Bone Marrow Transplantation ,Mice, Knockout ,Sex Characteristics ,biology ,business.industry ,Mice, Inbred C57BL ,medicine.anatomical_structure ,Endocrinology ,Cytokine ,Leukocytes, Mononuclear ,biology.protein ,Female ,Bone marrow ,Cardiology and Cardiovascular Medicine ,business - Abstract
There are clinically relevant differences in symptomatology, risk stratification, and efficacy of therapies between men and women with coronary artery disease. Sex-based differences in plaque attenuation after administration of bone marrow mononuclear cells (BMNCs) are unknown. Forty-five male and 57 female apolipoprotein-E knockout (apoE −/− ) mice were fed a high-fat diet. At 14 weeks of age, animals received 4 biweekly intravenous sex-matched (males, n=11; females, n=13) or -mismatched (males, n=12; females, n=14) BMNCs obtained from C57BL6/J mice. The rest of the apoE −/− mice were vehicle treated (males, n=13; females, n=20) or were age-matched untreated controls (males, n=9; females, n=10). Aortic plaque burden, progenitor cell profiles in bone marrow (BM) and 22 circulating cytokines/chemokines were examined 1 week following the final injection. Only female BMNCs infused into male apoE −/− recipients significantly decreased plaque formation ( P + ( P =0.02), CD45 + ( P =0.0001), and AC133 + /CD34 + ( P =0.001) cell percentages in the BM of recipients but not with total serum cholesterol or percentage of BM-CD31 + /CD45 low cells. In a multivariate analysis, BM-AC133 + /CD34 + and BM-CD45 + percentage counts correlated with a lower plaque burden ( P r =−0.86, P =0.0004). In untreated apoE −/− mice of either sex, BM-AC133 + /CD34 + cells rose initially and then fell as plaque accumulated; however, BM-AC133 + /CD34 + percentages were higher in females at all times ( P ≤0.01). We have demonstrated an atheroprotective effect of female-derived BMNCs administered to male atherosclerotic apoE −/− mice; this reparative response correlated with the upregulation of BM-AC133 + /CD34 + and CD45 + cells and of circulating granulocyte colony-stimulating factor. Atherosclerotic female apoE −/− mice did not exhibit atheroprotection after BMNCs of either sex. Our findings may have implications for clinical cell therapy trials for coronary artery disease. Further exploration of sex-based differences in atheroprotection and vascular repair is warranted.
- Published
- 2007
25. Using nature's platform to engineer bio-artificial lungs
- Author
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Sarah E. Gilpin and Harald C. Ott
- Subjects
Pulmonary and Respiratory Medicine ,Scaffold ,Pathology ,medicine.medical_specialty ,Decellularization ,Tissue Engineering ,Regeneration (biology) ,Induced Pluripotent Stem Cells ,Biology ,Artificial lung ,Cell biology ,Extracellular Matrix ,Extracellular matrix ,Perfusion ,Scaffold material ,medicine ,Animals ,Humans ,Regeneration ,Artificial Organs ,Lung ,Lung Transplantation - Abstract
Native lung extracellular matrix can be isolated from cadaveric organs via perfusion decellularization and provides a novel scaffold material for lung engineering. Based on this platform, several proof-of-principle studies have demonstrated the feasibility of whole organ recellularization and culture in rodent models and have helped us better understand the numerous challenges in up-scaling to clinically relevant tissues. Standardized protocols to generate whole lung scaffolds of porcine and human scale have been reported, but our understanding of the remaining extracellular matrix components and their properties is incomplete. Effective recellularization will require the isolation and in vitro expansion of clinically relevant cell sources, either from primary or stem cell-derived populations, and techniques to effectively deliver these populations throughout the lung scaffold. Ultimately, only tightly controlled recapitulation of tissue development and repair in vitro will enable us to mature lung grafts to function before implantation. Although substantial progress has been made, we are only beginning to grasp the complexity of this exciting new technology.
- Published
- 2015
26. Engineered composite tissue as a bioartificial limb graft
- Author
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Bernhard J. Jank, Linjie Xiong, Harald C. Ott, Leopoldo Fernandez, Shawn P. Fagan, David A. Leonard, Xi Ren, Philipp T. Moser, Curtis L. Cetrulo, and Jacques P. Guyette
- Subjects
Male ,medicine.medical_specialty ,medicine.medical_treatment ,Biophysics ,Bioengineering ,Artificial Limbs ,Prosthesis Design ,Article ,Biomaterials ,Extracellular matrix ,Rats, Sprague-Dawley ,On demand ,medicine ,Animals ,Composite tissue ,Muscle, Skeletal ,Cells, Cultured ,Decellularization ,Bioartificial Organs ,Cell-Free System ,Tissue Engineering ,Tissue Scaffolds ,business.industry ,Stem Cells ,Immunosuppression ,Cell Differentiation ,Surgery ,Extracellular Matrix ,Rats ,Transplantation ,Equipment Failure Analysis ,Mechanics of Materials ,Ceramics and Composites ,business ,Perfusion ,Hand transplantation - Abstract
The loss of an extremity is a disastrous injury with tremendous impact on a patient's life. Current mechanical prostheses are technically highly sophisticated, but only partially replace physiologic function and aesthetic appearance. As a biologic alternative, approximately 70 patients have undergone allogeneic hand transplantation to date worldwide. While outcomes are favorable, risks and side effects of transplantation and long-term immunosuppression pose a significant ethical dilemma. An autologous, bio-artificial graft based on native extracellular matrix and patient derived cells could be produced on demand and would not require immunosuppression after transplantation. To create such a graft, we decellularized rat and primate forearms by detergent perfusion and yielded acellular scaffolds with preserved composite architecture. We then repopulated muscle and vasculature with cells of appropriate phenotypes, and matured the composite tissue in a perfusion bioreactor under electrical stimulation in vitro. After confirmation of composite tissue formation, we transplanted the resulting bio-composite grafts to confirm perfusion in vivo.
- Published
- 2015
27. From cardiac repair to cardiac regeneration – ready to translate?
- Author
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Doris A. Taylor and Harald C. Ott
- Subjects
medicine.medical_specialty ,Cellular differentiation ,Muscle Fibers, Skeletal ,Clinical Biochemistry ,Cardiology ,Bone Marrow Cells ,Disease ,Regenerative Medicine ,Cell therapy ,Drug Discovery ,Cellular cardiomyoplasty ,Animals ,Humans ,Regeneration ,Medicine ,Myocytes, Cardiac ,Progenitor cell ,Intensive care medicine ,Cell Proliferation ,Pharmacology ,Tissue Engineering ,business.industry ,Regeneration (biology) ,Cell Differentiation ,Papillary Muscles ,medicine.disease ,Surgery ,Transplantation ,Cardiovascular Diseases ,Heart failure ,business ,Stem Cell Transplantation - Abstract
Cardiovascular disease is a major public health challenge in the western world. Mortality of acute events has improved, but more patients develop HF--a condition affecting up to 22 million people worldwide. Cell transplantation is the first therapy to attempt replacement of lost cardiomyocytes and vasculature to restore lost contractile function. Since the first reported functional repair after injection of autologous skeletal myoblasts into the injured heart in 1998, a variety of cell types have been proposed for transplantation in different stages of cardiovascular disease. Fifteen years of preclinical research and the rapid move into clinical studies have left us with promising results and a better understanding of cells as a potential clinical tool. Cell-based cardiac repair has been the first step, but cardiac regeneration remains the more ambitious goal. Promising new cell types and the rapidly evolving concept of adult stem and progenitor cell fate may enable us to move towards regenerating viable and functional myocardium. Meeting a multidisciplinary consensus will be required to translate these findings into safe and applicable clinical tools.
- Published
- 2006
28. Robotic minimally invasive cell transplantation for heart failure
- Author
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Samuel A. Barnes, Wendy Nelson, Harald C. Ott, Doris A. Taylor, Tanya Feldberg, Johannes Brechtken, Cory Swingen, and Thomas S Matthiesen
- Subjects
Pulmonary and Respiratory Medicine ,medicine.medical_specialty ,Cell Transplantation ,Swine ,Myoblasts, Skeletal ,medicine.medical_treatment ,Diastole ,030204 cardiovascular system & hematology ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,Animals ,Medicine ,Pericardium ,Thoracotomy ,Heart Failure ,business.industry ,Robotics ,Perioperative ,medicine.disease ,Magnetic Resonance Imaging ,3. Good health ,Surgery ,Cardiac surgery ,Transplantation ,medicine.anatomical_structure ,Ventricle ,030220 oncology & carcinogenesis ,Heart failure ,Cardiology ,business ,Cardiology and Cardiovascular Medicine - Abstract
Cardiac cell transplantation offers new opportunities as a potent therapeutic tool to improve left ventricular (LV) function and reverse postinfarction remodeling in ischemic heart disease. Skeletal myoblasts (SKMBs) engraft within infarcted myocardium, form myotubes, induce angiogenesis, and improve both diastolic and systolic LV function. 1 Bone marrow‐derived mononuclear cells (BM-MNCs) likewise engraft, increase angiogenesis, and improve myocardial perfusion. 2 Both cell types have moved to clinical testing, and preclinical studies suggest that they could have synergistic functional benefits that argue for combined transplantation. 3,4 Intramyocardial injections are currently performed either percutaneously through an endoventricular or transvenous approach or surgically through a thoracotomy or sternotomy. We recently reported a video-assisted thoracoscopic technique to reduce invasiveness and perioperative risk of surgical cell delivery that was tested in uninjured swine hearts. 5 In the setting of heart failure (HF), mechanical manipulation of the left ventricle both by means of stabilization and cell injection must be minimized to prevent hemodynamic compromise, arrhythmia, and ventricular perforation. Robotically assisted cardiac surgery combines the advantages of minimal invasiveness and thoracoscopic access but adds a 3-dimensional view and 7 degrees of freedom that requires less cardiac manipulation than with the 2-dimensional view and limited freedom of motion of video-assisted thoracoscopic surgery. 6 We therefore propose a robot-assisted, beating-heart cell transplantation technique for use in severe HF to increase safety, optimize targeting, and reduce procedural time.
- Published
- 2006
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29. Cell Therapy for Heart Failure—Muscle, Bone Marrow, Blood, and Cardiac-Derived Stem Cells
- Author
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Doris A. Taylor, Bryce H. Davis, and Harald C. Ott
- Subjects
Pulmonary and Respiratory Medicine ,medicine.medical_specialty ,Myoblasts, Skeletal ,medicine.medical_treatment ,Population ,Myocardial Infarction ,Hematopoietic stem cell transplantation ,Mesenchymal Stem Cell Transplantation ,Ventricular Function, Left ,Cell therapy ,medicine ,Animals ,Humans ,Myocardial infarction ,Cardiomyoplasty ,Coronary Artery Bypass ,education ,Intensive care medicine ,Bone Marrow Transplantation ,Heart Failure ,education.field_of_study ,business.industry ,Hematopoietic Stem Cell Transplantation ,General Medicine ,medicine.disease ,Myocardial Contraction ,Surgery ,Transplantation ,medicine.anatomical_structure ,Heart failure ,Bone marrow ,Stem cell ,Cardiology and Cardiovascular Medicine ,business ,Stem Cell Transplantation - Abstract
Heart failure (HF) affects a rapidly growing population of patients. Despite improvements in the understanding and therapy of many stages of cardiovascular disease, there has been little progress in treating HF. In the late-stage disease, current options are cardiac transplantation and mechanical support--options that are limited to a small patient collective. The ischemically injured failing heart lacks contractile myocardium, functional vasculature, and electrical integrity, which has made treatment of the underlying injury untenable in the past. Restoring all of these components seems an overwhelming challenge. Yet, the concept of cell therapy--tissue repair by transplantation of stem and progenitor cells--has opened new potential options for patients with heart failure. Skeletal myoblasts, bone marrow, and blood-derived stem cells have all shown considerable myogenic and angiogenic potential in vitro and have rapidly moved from bench to bedside. A number of nonrandomized, non-placebo-controlled safety and feasibility studies have been reported and now double-blinded randomized controlled trials are underway. Despite this rapid clinical pace, the exact mechanisms underlying the functional benefits of different cell types are not well understood. Instead, multiple similar mechanism have been ascribed to virtually every cell type. Thus, while the field is exciting and offers unheralded promise to treat patients with CVD, we must proceed with due diligence and caution. Only a deep understanding of the benefits versus the risks, and the mechanisms involved in cell-mediated cardiac repair, will allow us to design clinically valuable tools and fulfill the potential of this exciting 21st century approach to treating cardiovascular disease.
- Published
- 2005
30. Cell–based cardiovascular repair
- Author
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Jonathan D. McCue, Harald C. Ott, and Doris A. Taylor
- Subjects
medicine.medical_specialty ,Physiology ,business.industry ,Vascular disease ,Skeletal Myoblasts ,Disease ,medicine.disease ,Cell therapy ,Physiology (medical) ,Immunology ,Animals ,Humans ,Medicine ,Hematopoietic progenitor cells ,Disease prevention ,Disease process ,Cardiomyopathies ,Cardiology and Cardiovascular Medicine ,business ,Intensive care medicine ,Stem Cell Transplantation ,Cell based - Abstract
Cardiovascular cell therapy offers the first real potential to treat the underlying injuries associated with cardiac and vascular disease. By delivering appropriate exogenous cells to an injury site, the potential exists to mitigate injury or even to begin to reverse damage. Based on their inordinate pre-clinical promise as myogenic or angiogenic precursors, skeletal myoblasts and bone marrow or blood-derived mesenchymal and hematopoietic progenitor cells have all rapidly moved from bench to early clinical studies. From these parallel paths we are learning a number of useful lessons and have begun to visualize the hurdles to be overcome as we move these therapies forward. It is now obvious that cell-based cardiac and vascular repair are feasible-both early and later in the disease process. In fact, cell therapy may offer an unparalleled opportunity for improvement to millions of individuals living with cardiovascular disease. However, many questions about the technology remain. The mechanisms associated with cardiovascular repair remain unclear. Whether a best cell type, delivery method, or route of administration exists is unknown. And, whether cellbased disease prevention is feasible is still unanswerable. Now is the time to delve deeply into the questions of cell-based myocardial and vascular repair-even as we cautiously proceed clinically. Only by understanding these issues will we be able to decrease unanticipated clinical effects and to fulfill the potential promise of the most exciting opportunity yet to treat CVD. As we do so, we must prevent uncontrolled, poorly planned studies and until we understand cell therapy's potential, we must limit "too good to be true" promises. Only by addressing unanswered questions, carefully limiting our promises, and rigorously performing pre-clinical and clinical studies can we provide the surest opportunity for safely moving the field forward.
- Published
- 2005
31. Intramyocardial microdepot injection increases the efficacy of skeletal myoblast transplantation
- Author
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Nikolaos Bonaros, Steffen Hering, Ruth Kroess, Eva Margreiter, Rainer Marksteiner, Harald C. Ott, Thomas Schachner, and Guenther Laufer
- Subjects
Male ,Pulmonary and Respiratory Medicine ,medicine.medical_specialty ,Microinjections ,Myoblasts, Skeletal ,Myocardial Infarction ,Infarction ,Internal medicine ,Cellular cardiomyoplasty ,medicine ,Animals ,Myocardial infarction ,Ejection fraction ,business.industry ,Myocardium ,Stroke Volume ,General Medicine ,medicine.disease ,Rats, Inbred F344 ,Rats ,Transplantation ,medicine.anatomical_structure ,Ventricle ,Circulatory system ,Cardiology ,Surgery ,Cardiology and Cardiovascular Medicine ,business ,Artery - Abstract
Objective: Recent progress in the field of cellular cardiomyoplasty has opened new prospects for the treatment of ischemic heart disease and currently moves from bench to bedside. The aim of the present study was to develop a novel cell delivery technique, reducing target tissue damage and improving cell dispersion and engraftment. Methods: In 30 male Fischer F344 rats an infarction of the left ventricle was generated by ligation of the left anterior descendent artery. Seven days after infarction, either 15 microdepots of 10 ml myoblast cell suspension (microdepot group) or culture medium (control group) were injected into the infarcted region using an automatic pressure injection device, or three depots of 50 ml myoblast cell suspension (macrodepot group) were injected using the standard surgical technique. Echocardiography was performed in all rats before and 6 weeks after cell injection. In all groups the perioperative mortality was below 20%. Six weeks after cell transplantation, a significant improvement of ejection fraction was seen in both myoblast treated groups compared to controls (macrodepot, microdepot, control; 53.7G11.9, 70.7G2.0, 39.1G6.4; PZ0.026, P!0.001). The microdepot group showed a more decent improvement than the macrodepot group (70.7G2.0 vs. 53.7G11.9, PZ0.013). In both treated groups, grafted myoblasts differentiated into multinucleated myotubes within host myocardium, however, the engraftment pattern was different and angiogenesis was enhanced in the microdepot group. Conclusions: Intramyocardial multisite pressure injection allows the safe and reliable transplantation of several myoblast microdepots into an infarcted myocardium and improves the efficacy of myoblast transplantation compared to the standard technique. Q 2005 Elsevier B.V. All rights reserved.
- Published
- 2005
32. Rapamycin treatment is associated with an increased apoptosis rate in experimental vein grafts☆
- Author
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Yping Zou, Günther Laufer, Johannes Bonatti, Alexander Oberhuber, Alexandar Tzankov, Thomas Schachner, and Harald C. Ott
- Subjects
Pulmonary and Respiratory Medicine ,Neointima ,medicine.medical_specialty ,Urology ,Apoptosis ,Inferior vena cava ,Coronary Restenosis ,Mice ,medicine.artery ,In Situ Nick-End Labeling ,medicine ,Animals ,Common carotid artery ,Vein ,Antibacterial agent ,Sirolimus ,Neointimal hyperplasia ,Mice, Inbred BALB C ,Hyperplasia ,business.industry ,Graft Occlusion, Vascular ,General Medicine ,medicine.disease ,Surgery ,medicine.anatomical_structure ,medicine.vein ,cardiovascular system ,Stents ,Tunica Intima ,Cardiology and Cardiovascular Medicine ,Vein graft disease ,business ,Immunosuppressive Agents - Abstract
Objective: Rapamycin is an immunosuppressive agent with marked antiproliferative properties and is effective in reducing in stent restenosis and vein graft neointimal hyperplasia. Apoptosis is one mechanism counterbalancing cellular proliferation. We therefore investigated the role of apoptosis in rapamycin treated vein grafts in a mouse model. Methods: C57BL6J mice underwent interposition of the inferior vena cava from isogenic donor mice into the common carotid artery using a cuff technique. In the treatment group 200 mg of rapamycin were applied locally in pluronic gel. The control group did not receive local treatment. Vein grafts were harvested at 4 weeks postoperatively and underwent morphometric analysis as well as immunohistochemical analysis for apoptosis (TUNEL). Results: In grafted veins without treatment (controls) neointimal thickness was 50 (12–58) mm at 4 weeks postoperatively. In 200 mg rapamycin treated grafts the neointimal thickness was 17 (5–55) mm. Rapamycin treated vein grafts showed a significantly increased rate of apoptosis in the adventitia as compared with controls (PZ0.032). In the neointima the apoptosis rate was lower in both groups with no significant difference between rapamycin treated grafts and controls. Conclusion: We conclude that treatment of experimental vein grafts with rapamycin is associated with an increased apoptosis rate in the vascular wall and a trend towards reduction of neointimal hyperplasia. These results suggest that apoptosis may be a beneficial antiproliferative component for the treatment of vein graft disease. q 2004 Elsevier B.V. All rights reserved.
- Published
- 2005
33. Design and validation of a clinical-scale bioreactor for long-term isolated lung culture
- Author
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Sarah E. Gilpin, Tatsuya Okamoto, Atsushi Yasuda, Harald C. Ott, Douglas J. Mathisen, Jonathan M. Charest, and Kentaro Kitano
- Subjects
medicine.medical_specialty ,Resuscitation ,Swine ,ex-vivo perfusion ,medicine.medical_treatment ,organ repair ,Biophysics ,Clinical scale ,Bioengineering ,Organ culture ,Article ,Biomaterials ,Bioreactors ,Organ Culture Techniques ,Bioreactor ,Isolated lung culture ,lung transplantation ,Medicine ,Lung transplantation ,Animals ,Humans ,Intensive care medicine ,Lung ,business.industry ,lung preservation ,Regeneration (biology) ,Equipment Design ,Organ Preservation ,Surgery ,Perfusion ,medicine.anatomical_structure ,Mechanics of Materials ,Ceramics and Composites ,business ,Ex vivo - Abstract
The primary treatment for end-stage lung disease is lung transplantation. However, donor organ shortage remains a major barrier for many patients. In recent years, techniques for maintaining lungs ex vivo for evaluation and short-term (
- Published
- 2014
34. Perfusion decellularization of whole organs
- Author
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Luis F. Tapias, Sarah E. Gilpin, Jacques P. Guyette, Jonathan M. Charest, Xi Ren, and Harald C. Ott
- Subjects
Scaffold ,Extracellular Matrix Proteins ,Decellularization ,Tissue Engineering ,Tissue Scaffolds ,Chemistry ,Swine ,Regeneration (biology) ,Detergents ,Anatomy ,General Biochemistry, Genetics and Molecular Biology ,Extracellular Matrix ,Rats ,Extracellular matrix ,Perfusion ,Viscera ,In vivo ,Pressure ,Animals ,Humans ,ECM Protein ,Ex vivo ,Biomedical engineering - Abstract
The native extracellular matrix (ECM) outlines the architecture of organs and tissues. It provides a unique niche of composition and form, which serves as a foundational scaffold that supports organ-specific cell types and enables normal organ function. Here we describe a standard process for pressure-controlled perfusion decellularization of whole organs for generating acellular 3D scaffolds with preserved ECM protein content, architecture and perfusable vascular conduits. By applying antegrade perfusion of detergents and subsequent washes to arterial vasculature at low physiological pressures, successful decellularization of complex organs (i.e., hearts, lungs and kidneys) can be performed. By using appropriate modifications, pressure-controlled perfusion decellularization can be achieved in small-animal experimental models (rat organs, 4-5 d) and scaled to clinically relevant models (porcine and human organs, 12-14 d). Combining the unique structural and biochemical properties of native acellular scaffolds with subsequent recellularization techniques offers a novel platform for organ engineering and regeneration, for experimentation ex vivo and potential clinical application in vivo.
- Published
- 2014
35. Decellularized scaffolds as a platform for bioengineered organs
- Author
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Luis F. Tapias and Harald C. Ott
- Subjects
medicine.medical_specialty ,medicine.medical_treatment ,Cell Culture Techniques ,Economic shortage ,Bioinformatics ,Organ transplantation ,Article ,Tissue engineering ,Tissue scaffolds ,medicine ,Immunology and Allergy ,Animals ,Humans ,Bioartificial Organ ,Transplantation ,Decellularization ,Bioartificial Organs ,Tissue Engineering ,Tissue Scaffolds ,business.industry ,Extramural ,Stem Cells ,Immunosuppression ,Organ Transplantation ,Tissue Donors ,Surgery ,business - Abstract
Patients suffering from end-stage organ failure requiring organ transplantation face donor organ shortage and adverse effect of chronic immunosuppression. Recent progress in the field of organ bioengineering based on decellularized organ scaffolds and patient-derived cells holds great promise to address these issues.Perfusion-decellularization is the most consistent method to obtain decellularized whole-organ scaffolds to serve as a platform for organ bioengineering. Important advances have occurred in organ bioengineering using decellularized scaffolds in small animal models. However, the function exhibited by bioengineered organs has been rudimentary. Pluripotent stem cells seem to hold promise as the ideal regenerative cells to be used with this approach but the techniques to effectively and reliably manipulate their fate are still to be discovered. Finally, this technology needs to be scaled up to human size to be of clinical relevance.The search for alternatives to allogeneic organ transplantation continues. Important milestones have been achieved in organ bioengineering with the use of decellularized scaffolds. However, many challenges remain on the way to producing an autologous, fully functional organ that can be transplanted similar to a donor organ.
- Published
- 2014
36. Enhanced lung epithelial specification of human induced pluripotent stem cells on decellularized lung matrix
- Author
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Sarah E. Gilpin, Jayaraj Rajagopal, Tatsuya Okamoto, Harald C. Ott, Jacques P. Guyette, Hongmei Mou, Douglas J. Mathisen, Xi Ren, and Joseph P. Vacanti
- Subjects
Pulmonary and Respiratory Medicine ,Cellular differentiation ,Population ,Induced Pluripotent Stem Cells ,Article ,Rats, Sprague-Dawley ,Perfusion Culture ,SOX2 ,Cadaver ,Medicine ,Animals ,Humans ,Progenitor cell ,education ,Induced pluripotent stem cell ,Lung ,Cells, Cultured ,education.field_of_study ,Decellularization ,biology ,Bioartificial Organs ,Tissue Scaffolds ,business.industry ,Graft Survival ,Cell Differentiation ,Epithelial Cells ,respiratory system ,respiratory tract diseases ,Cell biology ,Extracellular Matrix ,Rats ,Immunology ,biology.protein ,Surgery ,Cardiology and Cardiovascular Medicine ,business ,NK2 homeobox 1 ,Lung Transplantation - Abstract
Background Whole-lung scaffolds can be created by perfusion decellularization of cadaveric donor lungs. The resulting matrices can then be recellularized to regenerate functional organs. This study evaluated the capacity of acellular lung scaffolds to support recellularization with lung progenitors derived from human induced pluripotent stem cells (iPSCs). Methods Whole rat and human lungs were decellularized by constant-pressure perfusion with 0.1% sodium dodecyl sulfate solution. Resulting lung scaffolds were cryosectioned into slices or left intact. Human iPSCs were differentiated to definitive endoderm, anteriorized to a foregut fate, and then ventralized to a population expressing NK2 homeobox 1 (Nkx2.1). Cells were seeded onto slices and whole lungs, which were maintained under constant perfusion biomimetic culture. Lineage specification was assessed by quantitative polymerase chain reaction and immunofluorescent staining. Regenerated left lungs were transplanted in an orthotopic position. Results Activin-A treatment, followed by transforming growth factor-β inhibition, induced differentiation of human iPSCs to anterior foregut endoderm as confirmed by forkhead box protein A2 (FOXA2), SRY (Sex Determining Region Y)-Box 17 (SOX17), and SOX2 expression. Cells cultured on decellularized lung slices demonstrated proliferation and lineage commitment after 5 days. Cells expressing Nkx2.1 were identified at 40% to 60% efficiency. Within whole-lung scaffolds and under perfusion culture, cells further upregulated Nkx2.1 expression. After orthotopic transplantation, grafts were perfused and ventilated by host vasculature and airways. Conclusions Decellularized lung matrix supports the culture and lineage commitment of human iPSC-derived lung progenitor cells. Whole-organ scaffolds and biomimetic culture enable coseeding of iPSC-derived endothelial and epithelial progenitors and enhance early lung fate. Orthotopic transplantation may enable further in vivo graft maturation.
- Published
- 2014
37. Invited commentary
- Author
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Harald C. Ott
- Subjects
Pulmonary and Respiratory Medicine ,Bioartificial Organs ,Tissue Engineering ,Animals ,Humans ,Surgery ,Cell Separation ,Cardiology and Cardiovascular Medicine ,Lung ,Article ,Extracellular Matrix - Published
- 2013
38. Perspectives on whole-organ assembly: moving toward transplantation on demand
- Author
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Thomas W. Gilbert, Alejandro Soto-Gutierrez, Jason A. Wertheim, and Harald C. Ott
- Subjects
Organ engineering ,medicine.medical_specialty ,Tissue Engineering ,General Medicine ,Organ Transplantation ,Biology ,Regenerative Medicine ,Regenerative medicine ,Organ transplantation ,Rats ,Transplantation ,Mice ,On demand ,Immunology ,medicine ,Science in Medicine ,Animals ,Humans ,Intensive care medicine - Abstract
There is an ever-growing demand for transplantable organs to replace acute and chronically damaged tissues. This demand cannot be met by the currently available donor organs. Efforts to provide an alternative source have led to the development of organ engineering, a discipline that combines cell biology, tissue engineering, and cell/organ transplantation. Over the last several years, engineered organs have been implanted into rodent recipients and have shown modest function. In this article, we summarize the most recent advances in this field and provide a perspective on the challenges of translating this promising new technology into a proven regenerative therapy.
- Published
- 2012
39. Human Lung Cancer Cells Grown on Acellular Rat Lung Matrix Create Perfusable Tumor Nodules
- Author
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Michael J. Thrall, Harald C. Ott, Brandi N. Baird, Jonathan M. Kurie, Dhruva K. Mishra, Min P. Kim, and Shanda H. Blackmon
- Subjects
Pulmonary and Respiratory Medicine ,Male ,Pathology ,medicine.medical_specialty ,Lung Neoplasms ,Matrix (biology) ,Adenocarcinoma ,Models, Biological ,Article ,Extracellular matrix ,Rats, Sprague-Dawley ,Bioreactors ,Tissue engineering ,Cell Line, Tumor ,medicine ,Animals ,Humans ,Lung cancer ,Lung ,Decellularization ,Tissue Engineering ,business.industry ,respiratory system ,medicine.disease ,respiratory tract diseases ,Rats ,Extracellular Matrix ,Perfusion ,medicine.anatomical_structure ,Cell culture ,Surgery ,Cardiology and Cardiovascular Medicine ,business - Abstract
Background Extracellular matrix allows lung cancer to form its shape and grow. Recent studies on organ reengineering for orthotopic transplantation have provided a new avenue for isolating purified native matrix to use for growing cells. Whether human lung cancer cells grown in a decellularized rat lung matrix would create perfusable human lung cancer nodules was tested. Methods Rat lungs were harvested and native cells were removed using sodium dodecyl sulfate and Triton X-100 in a decellularization chamber to create a decellularized rat lung matrix. Human A549, H460, or H1299 lung cancer cells were placed into the decellularized rat lung matrix and grown in a customized bioreactor with perfusion of oxygenated media for 7 to 14 days. Results Decellularized rat lung matrix showed preservation of matrix architecture devoid of all rat cells. All three human lung cancer cell lines grown in the bioreactor developed tumor nodules with intact vasculature. Moreover, the lung cancer cells developed a pattern of growth similar to the original human lung cancer. Conclusions Overall, this study shows that human lung cancer cells form perfusable tumor nodules in a customized bioreactor on a decellularized rat lung matrix created by a customized decellularization chamber. The lung cancer cells grown in the matrix had features similar to the original human lung cancer. This ex vivo model can be used potentially to gain a deeper understanding of the biologic processes involved in human lung cancer.
- Published
- 2012
40. Enhanced in vivo function of bioartificial lungs in rats
- Author
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Joren C. Madsen, Joseph P. Vacanti, Samuel Suk Kim, Jeremy Song, Harald C. Ott, Douglas J. Mathisen, and Zhilin Liu
- Subjects
Pulmonary and Respiratory Medicine ,Lung Diseases ,Male ,medicine.medical_specialty ,medicine.medical_treatment ,Organ culture ,Rats, Sprague-Dawley ,Pneumonectomy ,Rats, Nude ,Organ Culture Techniques ,Oxygen Consumption ,In vivo ,medicine ,Animals ,Lung ,Lung Compliance ,Decellularization ,Bioartificial Organs ,business.industry ,Organ Preservation ,respiratory system ,respiratory tract diseases ,Surgery ,Rats ,Compliance (physiology) ,Perfusion ,Disease Models, Animal ,surgical procedures, operative ,medicine.anatomical_structure ,Chronic Disease ,Blood Gas Analysis ,Cardiology and Cardiovascular Medicine ,Cadaveric spasm ,business ,Lung Transplantation - Abstract
Background More than 11 million Americans live with chronic lung disease; in search for an alternative to donor organs, we attempted to regenerate lungs based on perfusion decellularized lung scaffolds that can be transplanted similar to a donor organ. Methods Cadaveric rat lungs were decellularized by detergent perfusion. Resulting scaffolds were mounted in bioreactors and seeded with endothelial and fetal lung cells. Biomimetic organ culture was maintained for 7 days. Resulting bioartificial left lungs were transplanted in orthotopic position after left pneumonectomy in rats. Cadaveric left lung transplants and pneumonectomies served as controls. Blood gas analyses, compliance testing, and fluoroscopies were performed on postoperative days 1, 7, and 14. Lungs were removed for final analysis on day 14. Results Perfusion decellularization of cadaveric lungs yielded acellular scaffolds with intact architecture and matrix composition. Alveolar volumes, number, and size were comparable in bioartificial and native lungs, as were gas exchange, vital capacity and compliance in vitro. After using improved graft preservation and postoperative weaning protocols, animals could be fully recovered, and bioartificial lung constructs provided oxygenation as long as 7 days at levels comparable to cadaveric lung transplants. Compliance, gas exchange, and radiographic appearance gradually declined over the subsequent 7 days owing to progressive graft consolidation and inflammation. Conclusions Perfusion decellularization of cadaveric lungs yields intact scaffolds that can be seeded with cells to generate bioartificial lung grafts. After orthotopic transplantation, grafts are perfused by the recipient's circulation, ventilated through the recipient's airway and provide gas exchange in vivo for 7 days.
- Published
- 2011
41. Organ engineering based on decellularized matrix scaffolds
- Author
-
Harald C. Ott and Jeremy Song
- Subjects
Organ engineering ,Scaffold ,Decellularization ,Tissue Engineering ,Tissue Scaffolds ,Decellularized matrix ,Regeneration (biology) ,Anatomy ,Organ Transplantation ,Biology ,Kidney ,Cell biology ,Extracellular Matrix ,Extracellular matrix ,Transplantation ,Perfusion ,Molecular Medicine ,Animals ,Humans ,Regeneration ,Myocytes, Cardiac ,Progenitor cell ,Molecular Biology ,Lung ,Pancreas - Abstract
End-organ failure is one of the major healthcare challenges in the Western world. Yet, donor organ shortage and the need for immunosuppression limit the impact of transplantation. The regeneration of whole organs could theoretically overcome these hurdles. Early milestones have been met by combining stem and progenitor cells with increasingly complex scaffold materials and culture conditions. Because the native extracellular matrix (ECM) guides organ development, repair and physiologic regeneration, it provides a promising alternative to synthetic scaffolds and a foundation for regenerative efforts. Perfusion decellularization is a novel technology that generates native ECM scaffolds with intact 3D anatomical architecture and vasculature. This review summarizes achievements to date and discusses the role of native ECM scaffolds in organ regeneration.
- Published
- 2010
42. Regeneration and orthotopic transplantation of a bioartificial lung
- Author
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Darrell N. Kotton, Joseph P. Vacanti, Ben Clippinger, Laertis Ikonomou, Harald C. Ott, Irina Pomerantseva, Christian Schuetz, and Claudius Conrad
- Subjects
Pathology ,medicine.medical_specialty ,Transplantation, Heterotopic ,General Biochemistry, Genetics and Molecular Biology ,Organ Culture Techniques ,In vivo ,medicine ,Cadaver ,Animals ,Humans ,Respiratory system ,Lung ,Cells, Cultured ,Decellularization ,Bioartificial Organs ,Tissue Scaffolds ,business.industry ,Guided Tissue Regeneration ,Regeneration (biology) ,Endothelial Cells ,General Medicine ,respiratory system ,Fetal Blood ,respiratory tract diseases ,Surgery ,Rats ,Respiratory Function Tests ,Transplantation ,Perfusion ,medicine.anatomical_structure ,Breathing ,business ,Lung Transplantation - Abstract
About 2,000 patients now await a donor lung in the United States. Worldwide, 50 million individuals are living with end-stage lung disease. Creation of a bioartificial lung requires engineering of viable lung architecture enabling ventilation, perfusion and gas exchange. We decellularized lungs by detergent perfusion and yielded scaffolds with acellular vasculature, airways and alveoli. To regenerate gas exchange tissue, we seeded scaffolds with epithelial and endothelial cells. To establish function, we perfused and ventilated cell-seeded constructs in a bioreactor simulating the physiologic environment of developing lung. By day 5, constructs could be perfused with blood and ventilated using physiologic pressures, and they generated gas exchange comparable to that of isolated native lungs. To show in vivo function, we transplanted regenerated lungs into orthotopic position. After transplantation, constructs were perfused by the recipient's circulation and ventilated by means of the recipient's airway and respiratory muscles, and they provided gas exchange in vivo for up to 6 h after extubation.
- Published
- 2009
43. Perfusion-decellularized matrix: using nature's platform to engineer a bioartificial heart
- Author
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Theoden I. Netoff, Lauren D. Black, Saik Kia Goh, Thomas S Matthiesen, Harald C. Ott, Stefan M. Kren, and Doris A. Taylor
- Subjects
Male ,medicine.medical_specialty ,Pathology ,Heart, Artificial ,General Biochemistry, Genetics and Molecular Biology ,Extracellular matrix ,Internal medicine ,medicine ,Cadaver ,Animals ,Decellularization ,Bioartificial Organs ,Tissue Engineering ,business.industry ,Myocardium ,Endothelial Cells ,General Medicine ,medicine.disease ,Rats, Inbred F344 ,Cardiovascular physiology ,Extracellular Matrix ,Rats ,Transplantation ,Perfusion ,Heart failure ,Tissue Decellularization ,Cardiology ,Stem cell ,business - Abstract
About 3,000 individuals in the United States are awaiting a donor heart; worldwide, 22 million individuals are living with heart failure. A bioartificial heart is a theoretical alternative to transplantation or mechanical left ventricular support. Generating a bioartificial heart requires engineering of cardiac architecture, appropriate cellular constituents and pump function. We decellularized hearts by coronary perfusion with detergents, preserved the underlying extracellular matrix, and produced an acellular, perfusable vascular architecture, competent acellular valves and intact chamber geometry. To mimic cardiac cell composition, we reseeded these constructs with cardiac or endothelial cells. To establish function, we maintained eight constructs for up to 28 d by coronary perfusion in a bioreactor that simulated cardiac physiology. By day 4, we observed macroscopic contractions. By day 8, under physiological load and electrical stimulation, constructs could generate pump function (equivalent to about 2% of adult or 25% of 16-week fetal heart function) in a modified working heart preparation.
- Published
- 2007
44. Combined transplantation of skeletal myoblasts and angiopoietic progenitor cells reduces infarct size and apoptosis and improves cardiac function in chronic ischemic heart failure
- Author
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Alfred Kocher, Nikolaos Bonaros, Alexandar Tzankov, Dominik Wolf, B Schlechta, Rauend Rauf, Guenther Laufer, Harald C. Ott, Johannes Bonatti, Steffen Hering, Thomas Schachner, and Eva Margreiter
- Subjects
Pulmonary and Respiratory Medicine ,Male ,medicine.medical_specialty ,Myoblasts, Skeletal ,Ischemia ,Myocardial Infarction ,Myocardial Ischemia ,Infarction ,Neovascularization, Physiologic ,Apoptosis ,Internal medicine ,Cellular cardiomyoplasty ,Medicine ,Animals ,Myocardial infarction ,Progenitor cell ,Heart Failure ,Ejection fraction ,business.industry ,medicine.disease ,Surgery ,Rats ,Transplantation ,Heart failure ,Chronic Disease ,Cardiology ,business ,Cardiology and Cardiovascular Medicine ,Stem Cell Transplantation - Abstract
Objectives Cellular cardiomyoplasty using skeletal myoblasts or angiopoietic progenitor cells offers a promising approach for the treatment of ischemic heart failure. Although several studies have shown encouraging results in acute myocardial infarction, the efficacy of cell therapy using skeletal myoblasts and angiopoietic progenitor cells in chronic ischemic heart disease remains undetermined. Methods Ischemic heart failure was induced by left anterior descending coronary artery ligation in nude rats: (1) Culture medium, (2) homologous skeletal myoblasts (SM), (3) human AC-133+ cells (SC), and (4) both skeletal myoblasts and AC-133+ cells (Comb) were injected in the infarct (SM) and peri-infarct area (SC) 4 weeks after infarction. Assessment of myocardial function included echocardiography 4 weeks after cell delivery. Histology was based on quantification of myocardial fibrosis, apoptosis, and capillary density. Results Left ventricular dilatation was attenuated and ejection fraction improved significantly after cell transplantation (SM: 59.4% ± 8.8%, SC: 60.3% ± 6.6%, Comb: 68.2% ± 5.6% vs control: 41.5% ± 7.4%, P = .0013). Quantification of scar tissue showed a significant reduction of infarct area in cell-treated animals (SM: 22.3% ± 9.1%, SC: 19.8% ± 7.6%, Comb: 13.2% ± 5.8% vs controls: 36.5% ± 8.2%, P = .008). Improvement of myocardial function was associated with reduced apoptotic index (SM: 3.2% ± 0.9%, SC: 3.1% ± 0.6%, Comb: 1.8% ± 0.8% vs controls: 10.3% ± 1.6%, P = .0002) and increased vascular density (SM: 5.2 ± 1.2, SC: 8.3 ± 1.8, Comb: 12.3 ± 2.3, controls: 1.9 ± 0.3, all capillary vessels/high-power field, P = .007) in animals after cellular cardiomyoplasty. Conclusions Combined transplantation of skeletal myoblasts and angiopoietic progenitor cells results in ventricular function improvement, reduction of scar size and myocardial apoptosis, and increased neoangiogenesis in chronic ischemia. Clinical studies are warranted to prove this new therapeutic concept.
- Published
- 2006
45. CD34+/CD133- circulating endothelial precursor cells (CEP): characterization, senescence and in vivo application
- Author
-
Paul Debbage, Eberhard Gunsilius, Harald C. Ott, Christian Koppelstaetter, Holger Rumpold, Ruth Koeck, Gerold Untergasser, and Dominik Wolf
- Subjects
CD31 ,Adult ,Cyclin-Dependent Kinase Inhibitor p21 ,Male ,Aging ,Endothelium ,Angiogenesis ,Population ,CD34 ,Myocardial Ischemia ,Antigens, CD34 ,Biology ,Biochemistry ,Cell Line ,Rats, Nude ,Endocrinology ,Antigens, CD ,Precursor cell ,von Willebrand Factor ,Genetics ,medicine ,Cell Adhesion ,Animals ,Humans ,AC133 Antigen ,education ,Molecular Biology ,Cellular Senescence ,Glycoproteins ,education.field_of_study ,Endothelial Cells ,Mesenchymal Stem Cells ,Cell Biology ,Cell cycle ,Middle Aged ,Cell biology ,Rats ,Platelet Endothelial Cell Adhesion Molecule-1 ,medicine.anatomical_structure ,Phenotype ,Immunology ,Models, Animal ,CD146 ,Peptides - Abstract
Circulating endothelial precursor cells (CEP) are interesting candidates for the treatment of ischemic diseases and for tumor targeting/imaging. We isolated a homogeneous population of CEP from CD34+/CD133− cells of peripheral blood that can be expanded easily on collagen-type-I coated plastic. CEP displayed a phenotype of mature endothelial cells (vWF, CD31, CD34, VEGF-R2, CD105, CD146) similar to that of cord-blood CEP and umbilical vein endothelial cells. They bound UEA-1 lectin, incorporated acetylated LDL and formed tube-like structures with capillary lumens in vitro. Weibel-Palade bodies were observed by electron microscopy. After 40–60 cell population doublings, CEP cultures underwent a terminal growth arrest, had shorter telomeres, up-regulated cell cycle inhibitory proteins, such as p21CIP1 and stained positive for senescence-associated-beta galactosidase. During the whole expansion period CEP retained their endothelial phenotype and a normal karyotype. CEP had the capacity to home to ischemic tissue in vivo after systemic injection in nude rats. The convenient expandability, the homogenous phenotype, the functional cellular senescence program, the regular karyotype and the homing capacity to ischemic myocardium suggest autologous CEP cultures as a safe and promising tool for cell-based therapeutic approaches in targeting ischemic tissue and tumors.
- Published
- 2005
46. Combined transplantation of skeletal myoblasts and bone marrow stem cells for myocardial repair in rats
- Author
-
Steffen Hering, Guenther Laufer, Thomas Schachner, Eva Margreiter, Rainer Marksteiner, Nikolaos Bonaros, D. Wolf, and Harald C. Ott
- Subjects
Pulmonary and Respiratory Medicine ,Male ,medicine.medical_specialty ,Myoblasts, Skeletal ,Urology ,Myocardial Infarction ,Peripheral blood mononuclear cell ,Ventricular Function, Left ,medicine ,Myocyte ,Animals ,Cardiomyoplasty ,Ventricular remodeling ,Bone Marrow Transplantation ,Ejection fraction ,Ventricular Remodeling ,business.industry ,Bone Marrow Stem Cell ,General Medicine ,medicine.disease ,Rats, Inbred F344 ,Surgery ,Rats ,Transplantation ,Disease Models, Animal ,medicine.anatomical_structure ,Bone marrow ,Stem cell ,Cardiology and Cardiovascular Medicine ,business - Abstract
Objectives: To prove whether intramyocardial transplantation of combined skeletal myoblasts (SM) and mononuclear bone marrow stem cells is superior to the isolated transplantation of these cell types after myocardial infarction in rats. Methods: In 67 male Fischer rats myocardial infarction was induced by direct ligature of the LAD. Seven days postinfarction baseline echocardiography and intramyocardial cell transplantation were performed. Via lateral thoracotomy 200 ml containing either 10 7 SMs or 10 7 bone marrow-derived mononuclear cells (BM-MNC) or a combination of 5 £ 10 6 of both cell types (MB) were injected in 10 –15 sites in and around the infarct zone. In controls (C) 200 ml of cell-free medium were injected in the same manner. Before injection both cell types were stained using a fluorescent cell linker kit (PKH, Sigma). In addition, SMs were transfected with green fluorescent protein. Nine weeks postinfarction follow-up echocardiography was performed and animals were sacrificed for further analysis. Results: At baseline echocardiography there was no difference in left ventricular ejection fraction (LVEF; C, SM, BM-MNC, MB: 60.1 ^ 3.2, 53.3 ^ 10.2, 53.1 ^ 8.7, 49 ^ 9.0%) and left ventricular end diastolic diameter (LVEDD; C, SM, BM-MNC, MB: 6.5 ^ 0.8, 5.17 ^ 0.8, 5.77 ^ 1.4, 6.25 ^ 0.8 mm) between the different therapeutic groups. Eight weeks after cell transplantation LVEDD was significantly increased in all animals except those that received a combination of myoblasts and bone marrow stem cells (MB; C, SM, BM-MNC, MB: 7.7 ^ 0.6 mm, P ¼ 0:001; 7.7 ^ 1.5 mm, P , 0:001; 7.7 ^ 1.1 mm, P ¼ 0:005; 6.6 ^ 1.7 mm, P ¼ 0:397). At the same time LVEF decreased significantly in the control group (C), stayed unchanged in animals that received bone marrow stem cells (BM-MNC) and increased in animals that received myoblasts (SM) and a combination of both cell types (MB; C, SM, BM-MNC, MB: 45.3 ^ 7.0%, P ¼ 0:05; 63.9 ^ 15.4%, P ¼ 0:044; 54.3 ^ 6.3%, P ¼ 0:607; 63.0 ^ 11.5%, P ¼ 0:039). Conclusions: The present data show that the concept of combining SMs with bone marrow-derived stem cells may be of clinical relevance by merging the beneficial effects of each cell line and potentially reducing the required cell quantity. Further studies are required to identify the exact mechanisms underlying this synergy and to allow full exploitation of its therapeutic potential. q 2004 Elsevier B.V. All rights reserved.
- Published
- 2003
47. Perivascular application of C-type natriuretic peptide attenuates neointimal hyperplasia in experimental vein grafts
- Author
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Johannes Bonatti, Harald C. Ott, Thomas Mairinger, Alexander Oberhuber, Thomas Schachner, Alexandar Tzankov, Yping Zou, and Günther Laufer
- Subjects
Pulmonary and Respiratory Medicine ,Male ,Pathology ,medicine.medical_specialty ,medicine.drug_class ,Administration, Topical ,Calponin ,Vena Cava, Inferior ,CD8-Positive T-Lymphocytes ,Inferior vena cava ,Mice ,medicine.artery ,medicine ,Natriuretic peptide ,Animals ,Common carotid artery ,Neointimal hyperplasia ,Hyperplasia ,biology ,business.industry ,Calcium-Binding Proteins ,Microfilament Proteins ,Graft Occlusion, Vascular ,Natriuretic Peptide, C-Type ,General Medicine ,Anatomy ,medicine.disease ,Tunica intima ,Mice, Inbred C57BL ,medicine.anatomical_structure ,medicine.vein ,biology.protein ,Surgery ,Cardiology and Cardiovascular Medicine ,Vein graft disease ,business ,Tunica Intima - Abstract
Objective: C-type natriuretic peptide (CNP), which is produced by vascular endothelial cells, exhibits anti-proliferative and antiinflammatory effects. Cytotoxic T-lymphocytes may be involved in vein graft disease. Attenuation of vein graft disease necessitates a remodelling of the arterialized vein towards a more contractile phenotype which is characterized, among other factors, by the calponin amount. We investigated the effects of perivascularly applied CNP in a mouse model of vein graft disease. Methods: C57BL6J mice underwent interposition of the inferior vena cava from isogenic donor mice into the common carotid artery using a previously described cuff technique. In the treatment group, 10 26 mol/l of CNP were applied locally in pluronic gel. The control group did not receive local treatment. Grafts were harvested at 1, 2, 4, and 8 weeks and underwent morphometric analysis as well as immunohistochemical analysis. Results :I n grafted veins without treatment (controls) median intimal thickness was 10 (6– 29), 12 (8 –40) mm, was 47 (12 –58), and 79 (62 –146) mm after 1, 2, 4 and 8 weeks, respectively. In the treatment groups, which received 10 26 mol/l of CNP, the intimal thickness was 5 (3 –6), 6 (4 – 15), 32 (5 –54), and 43 (39– 70) mm after 1, 2, 4 and 8 weeks, respectively. This reduction of intimal thickness was significant at 1, 2 and 8 weeks. Immunohistochemically, the reduction of intimal thickness was associated with a decreased infiltration of CD-8 positive cells and an increased amount of calponin in the CNP-treated grafts. Conclusion: We conclude that perivascular application of CNP inhibits neointimal hyperplasia of vein grafts in a mouse model. These results suggest that CNP may have a therapeutic potential for the prevention of vein graft disease. q 2003 Elsevier B.V. All rights reserved.
- Published
- 2003
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