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Influence of Storage Conditions on Decellularized Porcine Conjunctiva. Bioengineering (Basel) 2023; 10:bioengineering10030350. [PMID: 36978741 PMCID: PMC10045143 DOI: 10.3390/bioengineering10030350] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 02/22/2023] [Accepted: 03/03/2023] [Indexed: 03/16/2023] Open
Abstract
Porcine decellularized conjunctiva (PDC) represents a promising alternative source for conjunctival reconstruction. Methods of its re-epithelialization in vitro with primary human conjunctival epithelial cells (HCEC) have already been established. However, a long-term storage method is required for a simplified clinical use of PDC. This study investigates the influence of several storage variants on PDC. PDC were stored in (1) phosphate-buffered saline solution (PBS) at 4 °C, (2) in glycerol-containing epithelial cell medium (EM/gly) at −80 °C and (3) in dimethyl sulfoxide-containing epithelial cell medium (EM/DMSO) at −196 °C in liquid nitrogen for two and six months, respectively. Fresh PDC served as control. Histological structure, biomechanical parameters, the content of collagen and elastin and the potential of re-epithelialization with primary HCEC under cultivation for 14 days were compared (n = 4–10). In all groups, PDC showed a well-preserved extracellular matrix without structural disruptions and with comparable fiber density (p ≥ 0.74). Collagen and elastin content were not significantly different between the groups (p ≥ 0.18; p ≥ 0.13, respectively). With the exception of the significantly reduced tensile strength of PDC after storage at −196 °C in EM/DMSO for six months (0.46 ± 0.21 MPa, p = 0.02), no differences were seen regarding the elastic modulus, tensile strength and extensibility compared to control (0.87 ± 0.25 MPa; p ≥ 0.06). The mean values of the epithelialized PDC surface ranged from 51.9 ± 8.8% (−196 °C) to 78.3 ± 4.4% (−80 °C) and did not differ significantly (p ≥ 0.35). In conclusion, all examined storage methods were suitable for storing PDC for at least six months. All PDC were able to re-epithelialize, which rules out cytotoxic influences of the storage conditions and suggests preserved biocompatibility for in vivo application.
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2
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Trammell SR. Light-Assisted Drying for the Thermal Stabilization of Nucleic Acid Nanoparticles and Other Biologics. Methods Mol Biol 2023; 2709:117-130. [PMID: 37572276 DOI: 10.1007/978-1-0716-3417-2_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/14/2023]
Abstract
Cold-chain storage can be challenging and expensive for the transportation and storage of biologics, especially in low-resource settings. Nucleic acid nanoparticles (NANPs) are an example of new biological products that require refrigerated storage. Light-assisted drying (LAD) is a new processing technique to prepare biologics for anhydrous storage in a trehalose amorphous solid matrix at ambient temperatures. Small volume samples (10 μL) containing NANPs are irradiated with a 1064 nm laser to speed the evaporation of water and create an amorphous trehalose preservation matrix. In previous studies, samples were stored for 1 month at 4 °C or 20 °C without degradation. A FLIR SC655 mid-IR camera is used to record the temperature of samples during processing. The trehalose matrix was characterized using polarized light imaging to determine if crystallization occurred during processing or storage. Damage to LAD-processed NANPs was assessed after processing and storage using gel electrophoresis.
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Affiliation(s)
- Susan R Trammell
- Department of Physics and Optical Science, University of North Carolina at Charlotte, Charlotte, NC, USA.
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3
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Anh Lam P, Furr DP, Tran A, McKeough RQ, Beasock D, Chandler M, Afonin KA, Trammell SR. The Application of Light-Assisted Drying to the Thermal Stabilization of Nucleic Acid Nanoparticles. Biopreserv Biobank 2022; 20:451-460. [PMID: 36067075 PMCID: PMC9603253 DOI: 10.1089/bio.2022.0035] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Background: Cold-chain storage can be challenging and expensive for the transportation and storage of biologics, especially in low-resource settings. Nucleic acid nanoparticles (NANPs) are an example of new biological products that require refrigerated storage. Light-assisted drying (LAD) is a new processing technique to prepare biologics for anhydrous storage in a trehalose amorphous solid matrix at ambient temperatures. In this study, LAD was used to thermally stabilize four types of NANPs with differing structures and melting temperatures. Methods: Small volume samples (10 μL) containing NANPs were irradiated with a 1064 nm laser to speed the evaporation of water and create an amorphous trehalose preservation matrix. Samples were then stored for 1 month at 4°C or 20°C. A FLIR C655 mid-IR camera was used to record the temperature of samples during processing. The trehalose matrix was characterized using polarized light imaging (PLI) to determine if crystallization occurred during processing or storage. Damage to LAD-processed NANPs was assessed after processing and storage using gel electrophoresis. Results: Based on the end moisture content (EMC) as a function time and the thermal histories of samples, a LAD processing time of 30 min is sufficient to achieve low EMCs for the 10 μL samples used in this study. PLI demonstrates that the trehalose matrix was resistant to crystallization during processing and after storage at 4°C and at room temperature. The native-polyacrylamide gel electrophoresis results for DNA cubes, RNA cubes, and RNA rings indicate that the main structures of these NANPs were not damaged significantly after LAD processing and being stored at 4°C or at room temperature for 1 month. Conclusions: These preliminary studies indicate that LAD processing can stabilize NANPs for dry-state storage at room temperature, providing an alternative to refrigerated storage for these nanomedicine products.
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Affiliation(s)
- Phuong Anh Lam
- Department of Physics and Optical Science and University of North Carolina at Charlotte, Charlotte, North Carolina, USA
| | - Daniel P. Furr
- Department of Physics and Optical Science and University of North Carolina at Charlotte, Charlotte, North Carolina, USA
| | - Allison Tran
- Department of Chemistry, University of North Carolina at Charlotte, Charlotte, North Carolina, USA
| | - Riley Q. McKeough
- Department of Physics and Optical Science and University of North Carolina at Charlotte, Charlotte, North Carolina, USA
| | - Damian Beasock
- Department of Chemistry, University of North Carolina at Charlotte, Charlotte, North Carolina, USA
| | - Morgan Chandler
- Department of Chemistry, University of North Carolina at Charlotte, Charlotte, North Carolina, USA
| | - Kirill A. Afonin
- Department of Chemistry, University of North Carolina at Charlotte, Charlotte, North Carolina, USA
| | - Susan R. Trammell
- Department of Physics and Optical Science and University of North Carolina at Charlotte, Charlotte, North Carolina, USA
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4
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Strategies for development of decellularized heart valve scaffolds for tissue engineering. Biomaterials 2022; 288:121675. [DOI: 10.1016/j.biomaterials.2022.121675] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 07/02/2022] [Accepted: 07/06/2022] [Indexed: 01/01/2023]
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5
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Abstract
Thermal injuries may cause significant damage to large areas of the skin. Extensive and deep burn wounds require specialized therapy. The optimal method in the strategy of treating extensive, full thickness burns (III°) is the use of autologous split thickness skin grafts STSG (Busuioc et al. Rom J Morphol Embryol 4:1061-1067, 2012; Kitala D, Kawecki M, Klama-Baryła A, Łabuś W, Kraut M, Glik J, Ryszkiel I, Kawecki MP, Nowak M. Allogeneic vs. Autologous Skin Grafts in the Therapy of Patients with Burn Injuries: A Restrospective, Open-label Clinical Study with Pair Matching. Adv Clin Exp Med. 2016 Sep-Oct;25(5):923-929.; Glik J, Kawecki M, Kitala D, Klama-Baryła A, Łabuś W, Grabowski M, Durdzińska A, Nowak M, Misiuga M, Kasperczyk A. A new option for definitive burn wound closure - pair matching type of retrospective case-control study of hand burns in the hospitalized patients group in the Dr Stanislaw Sakiel Center for Burn Treatment between 2009 and 2015. Int Wound J. 2017 Feb 21. https://doi.org/10.1111/iwj.12720 . [Epub ahead of print]; Prim et al. May 24Wound Repair Regen., 2017; Grossova et al. Mar 31Ann Burns Fire Disasters 30:5-8, 2017). The main limitation of that method is the inadequate amount of healthy, undamaged skin (donor sites), which could be harvested and used as a graft. Moreover, donor sites are an additional wounds that require analgesic therapy, leave scars during the healing process and they are highly susceptible to infection (1-6). It must be emphasized that in terms of the treatment of severe, deep and extensive burns, and there should be no doubt that the search for a biocompatible skin substitute that would be able to replace autologous STSG is an absolute priority. The above-mentioned necessitates the search for new treatment methods of severe burn wounds. Such methods could consider the preparation and application of bioengineered, natural skin substitutes. At present, as the clinical standard considered by the physicians may be use of available biological skin substitutes, e.g., human allogeneic skin, in vitro cultured skin cells, acellular dermal matrix ADM and revitalized ADMs, etc. (Busuioc et al. Rom J Morphol Embryol 4:1061-1067, 2012; Kitala D, Kawecki M, Klama-Baryła A, Łabuś W, Kraut M, Glik J, Ryszkiel I, Kawecki MP, Nowak M. Allogeneic vs. Autologous Skin Grafts in the Therapy of Patients with Burn Injuries: A Restrospective, Open-label Clinical Study with Pair Matching. Adv Clin Exp Med. 2016 Sep-Oct;25(5):923-929.; Glik J, Kawecki M, Kitala D, Klama-Baryła A, Łabuś W, Grabowski M, Durdzińska A, Nowak M, Misiuga M, Kasperczyk A. A new option for definitive burn wound closure - pair matching type of retrospective case-control study of hand burns in the hospitalised patients group in the Dr Stanislaw Sakiel Center for Burn Treatment between 2009 and 2015. Int Wound J. 2017 Feb 21. https://doi.org/10.1111/iwj.12720 . [Epub ahead of print]; Prim et al. May 24Wound Repair Regen., 2017; Grossova et al. Mar 31Ann Burns Fire Disasters 30:5-8, 2017; Łabuś et al. FebJ Biomed Mater Res B Appl Biomater 106:726-733, 2018).
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Liu D, Caliskan S, Rashidfarokhi B, Oldenhof H, Jung K, Sieme H, Hilfiker A, Wolkers WF. Fourier transform infrared spectroscopy coupled with machine learning classification for identification of oxidative damage in freeze-dried heart valves. Sci Rep 2021; 11:12299. [PMID: 34112893 PMCID: PMC8192956 DOI: 10.1038/s41598-021-91802-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 06/01/2021] [Indexed: 11/09/2022] Open
Abstract
Freeze-drying can be used to ensure off-the-shelf availability of decellularized heart valves for cardiovascular surgery. In this study, decellularized porcine aortic heart valves were analyzed by nitroblue tetrazolium (NBT) staining and Fourier transform infrared spectroscopy (FTIR) to identify oxidative damage during freeze-drying and subsequent storage as well as after treatment with H2O2 and FeCl3. NBT staining revealed that sucrose at a concentration of at least 40% (w/v) is needed to prevent oxidative damage during freeze-drying. Dried specimens that were stored at 4 °C depict little to no oxidative damage during storage for up to 2 months. FTIR analysis shows that fresh control, freeze-dried and stored heart valve specimens cannot be distinguished from one another, whereas H2O2- and FeCl3-treated samples could be distinguished in some tissue section. A feed forward artificial neural network model could accurately classify H2O2 and FeCl3 treated samples. However, fresh control, freeze-dried and stored samples could not be distinguished from one another, which implies that these groups are very similar in terms of their biomolecular fingerprints. Taken together, we conclude that sucrose can minimize oxidative damage caused by freeze-drying, and that subsequent dried storage has little effects on the overall biochemical composition of heart valve scaffolds.
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Affiliation(s)
- Dejia Liu
- Biostabilization Laboratory, Lower Saxony Centre for Biomedical Engineering, Implant Research and Development, University of Veterinary Medicine Hannover, Stadtfelddamm 34, 30625, Hannover, Germany
| | - Sükrü Caliskan
- Biostabilization Laboratory, Lower Saxony Centre for Biomedical Engineering, Implant Research and Development, University of Veterinary Medicine Hannover, Stadtfelddamm 34, 30625, Hannover, Germany.,Unit for Reproductive Medicine, Clinic for Horses, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Bita Rashidfarokhi
- Biostabilization Laboratory, Lower Saxony Centre for Biomedical Engineering, Implant Research and Development, University of Veterinary Medicine Hannover, Stadtfelddamm 34, 30625, Hannover, Germany
| | - Harriëtte Oldenhof
- Unit for Reproductive Medicine, Clinic for Horses, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Klaus Jung
- Institute for Animal Breeding and Genetics, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Harald Sieme
- Unit for Reproductive Medicine, Clinic for Horses, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Andres Hilfiker
- Leibniz Research Laboratories for Biotechnology and Artificial Organs, Hannover Medical School, Hannover, Germany
| | - Willem F Wolkers
- Biostabilization Laboratory, Lower Saxony Centre for Biomedical Engineering, Implant Research and Development, University of Veterinary Medicine Hannover, Stadtfelddamm 34, 30625, Hannover, Germany. .,Unit for Reproductive Medicine, Clinic for Horses, University of Veterinary Medicine Hannover, Hannover, Germany.
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7
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Behmer Hansen RA, Wang X, Kaw G, Pierre V, Senyo SE. Accounting for Material Changes in Decellularized Tissue with Underutilized Methodologies. BIOMED RESEARCH INTERNATIONAL 2021; 2021:6696295. [PMID: 34159202 PMCID: PMC8187050 DOI: 10.1155/2021/6696295] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 05/05/2021] [Accepted: 05/21/2021] [Indexed: 11/17/2022]
Abstract
Tissue decellularization has rapidly developed to be a practical approach in tissue engineering research; biological tissue is cleared of cells resulting in a protein-rich husk as a natural scaffold for growing transplanted cells as a donor organ therapy. Minimally processed, acellular extracellular matrix reproduces natural interactions with cells in vitro and for tissue engineering applications in animal models. There are many decellularization techniques that achieve preservation of molecular profile (proteins and sugars), microstructure features such as organization of ECM layers (interstitial matrix and basement membrane) and organ level macrofeatures (vasculature and tissue compartments). While structural and molecular cues receive attention, mechanical and material properties of decellularized tissues are not often discussed. The effects of decellularization on an organ depend on the tissue properties, clearing mechanism, chemical interactions, solubility, temperature, and treatment duration. Physical characterization by a few labs including work from the authors provides evidence that decellularization protocols should be tailored to specific research questions. Physical characterization beyond histology and immunohistochemistry of the decellularized matrix (dECM) extends evaluation of retained functional features of the original tissue. We direct our attention to current technologies that can be employed for structure function analysis of dECM using underutilized tools such as atomic force microscopy (AFM), cryogenic electron microscopy (cryo-EM), dynamic mechanical analysis (DMA), Fourier-transform infrared spectroscopy (FTIR), mass spectrometry, and rheometry. Structural imaging and mechanical functional testing combined with high-throughput molecular analyses opens a new approach for a deeper appreciation of how cellular behavior is influenced by the isolated microenvironment (specifically dECM). Additionally, the impact of these features with different decellularization techniques and generation of synthetic material scaffolds with desired attributes are informed. Ultimately, this mechanical profiling provides a new dimension to our understanding of decellularized matrix and its role in new applications.
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Affiliation(s)
- Ryan A. Behmer Hansen
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
| | - Xinming Wang
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
| | - Gitanjali Kaw
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
| | - Valinteshley Pierre
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
| | - Samuel E. Senyo
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
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8
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Abstract
In this chapter, we describe how Fourier transform infrared spectroscopy (FTIR) can be applied in cryobiological research to study: structure and thermal properties of biomolecules in cells and tissues, physical properties of cryopreservation and freeze-drying formulations, and permeation of molecules into cells and tissues. An infrared spectrum gives information about characteristic molecular vibrations of specific groups in molecules, whereas the temperature dependence of specific infrared bands may reveal information about conformational and phase changes. Infrared spectroscopy is minimally invasive and does not require labeling, whereas spectra can be recorded in any physical state of a sample. Data acquisition and spectral processing procedures are described to study phase state changes of protective formulations, cell membrane phase behavior during freezing and drying, protein denaturation during heating, and permeation of protective molecules into tissues. The latter can be used to estimate incubation times needed to load tissues with sufficient amounts of protective agents for cryopreservation or freeze-drying.
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9
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Wang S, Trammell S, Elliott GD. Microwave- and Laser-Assisted Drying for the Anhydrous Preservation of Biologics. Methods Mol Biol 2021; 2180:203-220. [PMID: 32797413 DOI: 10.1007/978-1-0716-0783-1_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2023]
Abstract
Dry preservation has become an attractive approach for the long-term storage of biologics. By removing water from the matrix to solidify the sample, refrigeration needs are reduced, and thus storage costs are minimized and shipping logistics greatly simplified. This chapter describes two energy deposition technologies, namely, microwave and laser systems, that have recently been used to enhance the rate and nature of solution densification for the purpose of anhydrous preservation of feline oocytes, sperm, and egg white lysozyme in trehalose glass. Several physical screening methodologies used to determine the suitability of an amorphous matrix for biopreservation are also introduced in this chapter.
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Affiliation(s)
- Shangping Wang
- Department of Mechanical Engineering and Engineering Science, University of North Carolina at Charlotte, Charlotte, NC, USA
| | - Susan Trammell
- Department of Physics and Optical Science, University of North Carolina at Charlotte, Charlotte, NC, USA
| | - Gloria D Elliott
- Department of Mechanical Engineering and Engineering Science, University of North Carolina at Charlotte, Charlotte, NC, USA.
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10
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Wolkers WF, Oldenhof H. Principles Underlying Cryopreservation and Freeze-Drying of Cells and Tissues. Methods Mol Biol 2021; 2180:3-25. [PMID: 32797407 DOI: 10.1007/978-1-0716-0783-1_1] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Cryopreservation and freeze-drying can be used to preserve cells or tissues for prolonged periods. Vitrification, or ice-free cryopreservation, is an alternative to cryopreservation that enables cooling cells to cryogenic temperatures in the absence of ice. The processing pathways involved in (ice-free) cryopreservation and freeze-drying of cells and tissues, however, can be very damaging. In this chapter, we describe the principles underlying preservation of cells for which freezing and drying are normally lethal processes as well as for cells that are able to survive in a reversible state of suspended animation. Freezing results in solution effects injury and/or intracellular ice formation, whereas drying results in removal of (non-freezable) water normally bound to biomolecules, which is generally more damaging. Cryopreservation and freeze-drying require different types of protective agents. Different mechanistic modes of action of cryoprotective and lyoprotective agents are described including minimizing ice formation, preferential exclusion, water replacement, and vitrification. Furthermore, it is discussed how protective agents can be introduced into cells avoiding damage due to too large cell volume excursions, and how knowledge of cell-specific membrane permeability properties in various temperature regimes can be used to rationally design (ice-free) cryopreservation and freeze-drying protocols.
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Affiliation(s)
- Willem F Wolkers
- Unit for Reproductive Medicine-Clinic for Horses, University of Veterinary Medicine Hannover, Hannover, Germany. .,Biostabilization Laboratory-Lower Saxony Centre for Biomedical Engineering, Implant Research and Development, University of Veterinary Medicine Hannover, Hannover, Germany.
| | - Harriëtte Oldenhof
- Unit for Reproductive Medicine-Clinic for Horses, University of Veterinary Medicine Hannover, Hannover, Germany
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11
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Wolkers WF, Hilfiker A. Freeze-Drying of Decellularized Heart Valves for Off-the-Shelf Availability. Methods Mol Biol 2021; 2180:731-739. [PMID: 32797446 DOI: 10.1007/978-1-0716-0783-1_40] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Malfunctioning heart valves can cause severe health problems, which if left untreated can lead to death. One of the treatment options is to replace a diseased heart valve with a decellularized valve construct prepared from human or animal material. Decellularized tissue scaffolds closely resemble properties of native tissue, while lacking immunogenic factors of cellular components. After transplantation, circulating stem and progenitor cells of the patient adhere to the scaffold resulting in in vivo tissue regeneration of the valve. Decellularized heart valve scaffold implants need to be stored to be readily available whenever needed, which can be done by freeze-drying. The advantage of freeze-drying is that it does not require bulky and energy-consuming freezing equipment for storage and allows easy transport. This chapter outlines the entire process from decellularization to freeze-drying to obtain dry decellularized heart valves, which after a simple rehydration step, can be used as implants. The protocol is described for porcine heart valves, but procedures can easily be adapted for material obtained from other species.
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Affiliation(s)
- Willem F Wolkers
- Unit for Reproductive Medicine-Clinic for Horses, University of Veterinary Medicine Hannover, Hannover, Germany. .,Biostabilization Laboratory-Lower Saxony Centre for Biomedical Engineering, Implant Research and Development, University of Veterinary Medicine Hannover, Hannover, Germany.
| | - Andres Hilfiker
- Leibniz Research Laboratories for Biotechnology and Artificial Organs, Hannover Medical School, Hannover, Germany
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12
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In vitro calcification studies on bioprosthetic and decellularized heart valves under quasi-physiological flow conditions. Biodes Manuf 2020. [DOI: 10.1007/s42242-020-00110-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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13
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Ramm R, Goecke T, Theodoridis K, Hoeffler K, Sarikouch S, Findeisen K, Ciubotaru A, Cebotari S, Tudorache I, Haverich A, Hilfiker A. Decellularization combined with enzymatic removal of N-linked glycans and residual DNA reduces inflammatory response and improves performance of porcine xenogeneic pulmonary heart valves in an ovine in vivo model. Xenotransplantation 2019; 27:e12571. [PMID: 31769101 DOI: 10.1111/xen.12571] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 10/01/2019] [Accepted: 11/06/2019] [Indexed: 12/11/2022]
Abstract
BACKGROUND Limited availability of decellularized allogeneic heart valve substitutes restricts the clinical application thereof. Decellularized xenogeneic valves might constitute an attractive alternative; however, increased immunological hurdles have to be overcome. This study aims for the in vivo effect in sheep of decellularized porcine pulmonary heart valves (dpPHV) enzymatically treated for N-glycan and DNA removal. METHODS dpPHV generated by nine different decelluarization methods were characterized in respect of DNA, hydroxyproline, GAGs, and SDS content. Orthotopic implantation in sheep for six months of five groups of dpPHV (n = 3 each; 3 different decellularization protocols w/o PNGase F and DNase I treatment) allowed the analysis of function and immunological reaction in the ovine host. Allogenic doPHV implantations (n = 3) from a previous study served as control. RESULTS Among the decellularization procedures, Triton X-100 & SDS as well as trypsin & Triton X-100 resulted in highly efficient removal of cellular components, while the extracellular matrix remained intact. In vivo, the functional performance of dpPHV was comparable to that of allogeneic controls. Removal of N-linked glycans and DNA by enzymatic PNGase F and DNase I treatment had positive effects on the clinical performance of Triton X-100 & SDS dpPHV, whereas this treatment of trypsin & Triton X-100 dpPHV induced the lowest degree of inflammation of all tested xenogeneic implants. CONCLUSION Functional xenogeneic heart valve substitutes with a low immunologic load can be produced by decellularization combined with enzymatic removal of DNA and partial deglycosylation of dpPHV.
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Affiliation(s)
- Robert Ramm
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Hannover Medical School, Hannover, Germany
| | - Tobias Goecke
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Hannover Medical School, Hannover, Germany.,Department of Cardiac-, Thoracic-, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany
| | - Karolina Theodoridis
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Hannover Medical School, Hannover, Germany
| | - Klaus Hoeffler
- Department of Cardiac-, Thoracic-, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany
| | - Samir Sarikouch
- Department of Cardiac-, Thoracic-, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany
| | - Katja Findeisen
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Hannover Medical School, Hannover, Germany
| | - Anatol Ciubotaru
- Department of Cardiac-, Thoracic-, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany.,Cardiac Surgery Center, State Medical and Pharmaceutical University, Chisinau, Moldova
| | - Serghei Cebotari
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Hannover Medical School, Hannover, Germany.,Department of Cardiac-, Thoracic-, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany
| | - Igor Tudorache
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Hannover Medical School, Hannover, Germany.,Department of Cardiac-, Thoracic-, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany
| | - Axel Haverich
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Hannover Medical School, Hannover, Germany.,Department of Cardiac-, Thoracic-, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany
| | - Andres Hilfiker
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Hannover Medical School, Hannover, Germany.,Department of Cardiac-, Thoracic-, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany
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14
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Preservation strategies for decellularized pericardial scaffolds for off-the-shelf availability. Acta Biomater 2019; 84:208-221. [PMID: 30342283 DOI: 10.1016/j.actbio.2018.10.026] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 09/26/2018] [Accepted: 10/16/2018] [Indexed: 02/06/2023]
Abstract
Decellularized biological scaffolds hold great promise in cardiovascular surgery. In order to ensure off-the-shelf availability, routine use of decellularized scaffolds requires tissue banking. In this study, the suitability of cryopreservation, vitrification and freeze-drying for the preservation of decellularized bovine pericardial (DBP) scaffolds was evaluated. Cryopreservation was conducted using 10% DMSO and slow-rate freezing. Vitrification was performed using vitrification solution (VS83) and rapid cooling. Freeze-drying was done using a programmable freeze-dryer and sucrose as lyoprotectant. The impact of the preservation methods on the DBP extracellular matrix structure, integrity and composition was assessed using histology, biomechanical testing, spectroscopic and thermal analysis, and biochemistry. In addition, the cytocompatibility of the preserved scaffolds was also assessed. All preservation methods were found to be suitable to preserve the extracellular matrix structure and its components, with no apparent signs of collagen deterioration or denaturation, or loss of elastin and glycosaminoglycans. Biomechanical testing, however, showed that the cryopreserved DBP displayed a loss of extensibility compared to vitrified or freeze-dried scaffolds, which both displayed similar biomechanical behavior compared to non-preserved control scaffolds. In conclusion, cryopreservation altered the biomechanical behavior of the DBP scaffolds, which might lead to graft dysfunction in vivo. In contrast to cryopreservation and vitrification, freeze-drying is performed with non-toxic protective agents and does not require storage at ultra-low temperatures, thus allowing for a cost-effective and easy storage and transport. Due to these advantages, freeze-drying is a preferable method for the preservation of decellularized pericardium. STATEMENT OF SIGNIFICANCE: Clinical use of DBP scaffolds for surgical reconstructions or substitutions requires development of a preservation technology that does not alter scaffold properties during long-term storage. Conclusive investigation on adverse impacts of the preservation methods on DBP matrix integrity is still missing. This work is aiming to close this gap by studying three potential preservation technologies, cryopreservation, vitrification and freeze-drying, in order to achieve the off-the-shelf availability of DBP patches for clinical application. Furthermore, it provides novel insights for dry-preservation of decellularized xenogeneic scaffolds that can be used in the routine clinical cardiovascular practice, allowing the surgeon the opportunity to choose an ideal implant matching with the needs of each patient.
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Vásquez-Rivera A, Oldenhof H, Dipresa D, Goecke T, Kouvaka A, Will F, Haverich A, Korossis S, Hilfiker A, Wolkers WF. Use of sucrose to diminish pore formation in freeze-dried heart valves. Sci Rep 2018; 8:12982. [PMID: 30154529 PMCID: PMC6113295 DOI: 10.1038/s41598-018-31388-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Accepted: 08/17/2018] [Indexed: 12/16/2022] Open
Abstract
Freeze-dried storage of decellularized heart valves provides easy storage and transport for clinical use. Freeze-drying without protectants, however, results in a disrupted histoarchitecture after rehydration. In this study, heart valves were incubated in solutions of various sucrose concentrations and subsequently freeze-dried. Porosity of rehydrated valves was determined from histological images. In the absence of sucrose, freeze-dried valves were shown to have pores after rehydration in the cusp, artery and muscle sections. Use of sucrose reduced pore formation in a dose-dependent manner, and pretreatment of the valves in a 40% (w/v) sucrose solution prior to freeze-drying was found to be sufficient to completely diminish pore formation. The presence of pores in freeze-dried valves was found to coincide with altered biomechanical characteristics, whereas biomechanical parameters of valves freeze-dried with enough sucrose were not significantly different from those of valves not exposed to freeze-drying. Multiphoton imaging, Fourier transform infrared spectroscopy, and differential scanning calorimetry studies revealed that matrix proteins (i.e. collagen and elastin) were not affected by freeze-drying.
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Affiliation(s)
| | - Harriëtte Oldenhof
- Unit for Reproductive Medicine, Clinic for Horses, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Daniele Dipresa
- Department of Cardiothoracic, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany.,Lower Saxony Centre for Biomedical Engineering Implant Research and Development, Hannover Medical School, Hannover, Germany
| | - Tobias Goecke
- Leibniz Research Laboratories for Biotechnology and Artificial Organs, Hannover Medical School, Hannover, Germany
| | - Artemis Kouvaka
- Department of Cardiothoracic, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany.,Lower Saxony Centre for Biomedical Engineering Implant Research and Development, Hannover Medical School, Hannover, Germany
| | - Fabian Will
- LLS ROWIAK LaserLabSolutions, Hannover, Germany
| | - Axel Haverich
- Department of Cardiothoracic, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany.,Leibniz Research Laboratories for Biotechnology and Artificial Organs, Hannover Medical School, Hannover, Germany.,Lower Saxony Centre for Biomedical Engineering Implant Research and Development, Hannover Medical School, Hannover, Germany
| | - Sotirios Korossis
- Department of Cardiothoracic, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany.,Lower Saxony Centre for Biomedical Engineering Implant Research and Development, Hannover Medical School, Hannover, Germany
| | - Andres Hilfiker
- Leibniz Research Laboratories for Biotechnology and Artificial Organs, Hannover Medical School, Hannover, Germany
| | - Willem F Wolkers
- Institute of Multiphase Processes, Leibniz Universität Hannover, Hannover, Germany.
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16
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Preservation Strategies that Support the Scale-up and Automation of Tissue Biomanufacturing. CURRENT STEM CELL REPORTS 2018. [DOI: 10.1007/s40778-018-0126-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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17
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Goecke T, Theodoridis K, Tudorache I, Ciubotaru A, Cebotari S, Ramm R, Höffler K, Sarikouch S, Vásquez Rivera A, Haverich A, Wolkers WF, Hilfiker A. In vivo performance of freeze-dried decellularized pulmonary heart valve allo- and xenografts orthotopically implanted into juvenile sheep. Acta Biomater 2018; 68:41-52. [PMID: 29191508 DOI: 10.1016/j.actbio.2017.11.041] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 11/10/2017] [Accepted: 11/14/2017] [Indexed: 11/16/2022]
Abstract
The decellularization of biological tissues decreases immunogenicity, allows repopulation with cells, and may lead to improved long-term performance after implantation. Freeze drying these tissues would ensure off-the-shelf availability, save storage costs, and facilitates easy transport. This study evaluates the in vivo performance of freeze-dried decellularized heart valves in juvenile sheep. TritonX-100 and sodium dodecylsulfate decellularized ovine and porcine pulmonary valves (PV) were freeze-dried in a lyoprotectant sucrose solution. After rehydration for 24 h, valves were implanted into the PV position in sheep as allografts (fdOPV) and xenografts (fdPPV), while fresh dezellularized ovine grafts (frOPV) were implanted as controls. Functional assessment was performed by transesophageal echocardiography at implantation and at explantation six months later. Explanted grafts were analysed histologically to assess the matrix, and immunofluorescence stains were used to identify the repopulating cells. Although the graft diameters and orifice areas increased, good function was maintained, except for one insufficient, strongly deteriorated frOPV. Cells which were positive for either endothelial or interstitial markers were found in all grafts. In fdPPV, immune-reactive cells were also found. Our findings suggest that freeze-drying does not alter the early hemodynamic performance and repopulation potential of decellularized grafts in vivo, even in the challenging xenogeneic situation. Despite evidence of an immunological reaction for the xenogenic valves, good early functionalities were achieved. STATEMENT OF SIGNIFICANCE Decellularized allogeneic heart valves show excellent results as evident from large animal experiments and clinical trials. However, a long-term storing method is needed for an optimal use of this limited resource in the clinical setting, where an optimized matching of graft and recipient is requested. As demonstrated in this study, freeze-dried and freshly decellularized grafts reveal equally good results after implantation in the juvenile sheep concerning function and repopulation with recipients' cells. Thus, freeze-drying arises as a promising method to extend the shelf-life of valvular grafts compared to those stored in antibiotic-solution as currently practised.
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Affiliation(s)
- Tobias Goecke
- Department of Cardiac-, Thoracic-, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany; Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Hannover Medical School, Hannover, Germany
| | - Karolina Theodoridis
- Department of Cardiac-, Thoracic-, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany; Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Hannover Medical School, Hannover, Germany
| | - Igor Tudorache
- Department of Cardiac-, Thoracic-, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany; Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Hannover Medical School, Hannover, Germany
| | - Anatol Ciubotaru
- Department of Cardiac-, Thoracic-, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany
| | - Serghei Cebotari
- Department of Cardiac-, Thoracic-, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany; Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Hannover Medical School, Hannover, Germany
| | - Robert Ramm
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Hannover Medical School, Hannover, Germany
| | - Klaus Höffler
- Department of Cardiac-, Thoracic-, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany
| | - Samir Sarikouch
- Department of Cardiac-, Thoracic-, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany
| | | | - Axel Haverich
- Department of Cardiac-, Thoracic-, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany; Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Hannover Medical School, Hannover, Germany
| | - Willem F Wolkers
- Institute of Multiphase Processes, Leibniz Universität Hannover, Hannover, Germany
| | - Andres Hilfiker
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Hannover Medical School, Hannover, Germany.
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18
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Vásquez-Rivera A, Sommer KK, Oldenhof H, Higgins AZ, Brockbank KGM, Hilfiker A, Wolkers WF. Simultaneous monitoring of different vitrification solution components permeating into tissues. Analyst 2018; 143:420-428. [DOI: 10.1039/c7an01576c] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Cryopreservation can be used for long-term preservation of tissues and organs.
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Affiliation(s)
| | - Kim K. Sommer
- Institute of Multiphase Processes
- Leibniz Universität Hannover
- Hannover
- Germany
| | - Harriëtte Oldenhof
- Unit for Reproductive Medicine
- Clinic for Horses
- University of Veterinary Medicine Hannover
- Hannover
- Germany
| | - Adam Z. Higgins
- School of Chemical
- Biological and Environmental Engineering
- Oregon State University
- Corvallis
- USA
| | | | - Andres Hilfiker
- Leibniz Research Laboratories for Biotechnology and Artificial Organs
- Hannover Medical School
- Hannover
- Germany
| | - Willem F. Wolkers
- Institute of Multiphase Processes
- Leibniz Universität Hannover
- Hannover
- Germany
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19
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Elliott GD, Wang S, Fuller BJ. Cryoprotectants: A review of the actions and applications of cryoprotective solutes that modulate cell recovery from ultra-low temperatures. Cryobiology 2017; 76:74-91. [DOI: 10.1016/j.cryobiol.2017.04.004] [Citation(s) in RCA: 180] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Revised: 04/07/2017] [Accepted: 04/16/2017] [Indexed: 02/08/2023]
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20
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Kawecki M, Łabuś W, Klama-Baryla A, Kitala D, Kraut M, Glik J, Misiuga M, Nowak M, Bielecki T, Kasperczyk A. A review of decellurization methods caused by an urgent need for quality control of cell-free extracellular matrix' scaffolds and their role in regenerative medicine. J Biomed Mater Res B Appl Biomater 2017; 106:909-923. [DOI: 10.1002/jbm.b.33865] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 10/12/2016] [Accepted: 01/26/2017] [Indexed: 12/30/2022]
Affiliation(s)
- Marek Kawecki
- Dr Stanislaw Sakiel Centre for Burns Treatment in Siemianowice Slaskie; Poland
- University of Technology and Humanities in Bielsko-Biała; Department of Health Science in Bielsko-Biała; Poland
| | - Wojciech Łabuś
- Dr Stanislaw Sakiel Centre for Burns Treatment in Siemianowice Slaskie; Poland
| | | | - Diana Kitala
- Dr Stanislaw Sakiel Centre for Burns Treatment in Siemianowice Slaskie; Poland
| | - Malgorzata Kraut
- Dr Stanislaw Sakiel Centre for Burns Treatment in Siemianowice Slaskie; Poland
| | - Justyna Glik
- Dr Stanislaw Sakiel Centre for Burns Treatment in Siemianowice Slaskie; Poland
- The Medical University of Silesia in Katowice; Unit for Chronic Wound Treatment Organization, Nursery Division; School of Healthcare in Zabrze Poland
| | - Marcelina Misiuga
- Dr Stanislaw Sakiel Centre for Burns Treatment in Siemianowice Slaskie; Poland
| | - Mariusz Nowak
- Dr Stanislaw Sakiel Centre for Burns Treatment in Siemianowice Slaskie; Poland
| | - Tomasz Bielecki
- Saint Barbara's Clinical Hospital number 5 in Sosnowiec; Clinical Department of Orthopaedics, Trauma; Oncologic and Reconstructive Surgery Poland
| | - Aleksandra Kasperczyk
- Medical University of Silesia in Katowice; Department of Biochemistry, School of Medicine with the Division of Dentistry in Zabrze
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Díaz-Moreno E, Durand-Herrera D, Carriel V, Martín-Piedra MÁ, Sánchez-Quevedo MDC, Garzón I, Campos A, Fernández-Valadés R, Alaminos M. Evaluation of freeze-drying and cryopreservation protocols for long-term storage of biomaterials based on decellularized intestine. J Biomed Mater Res B Appl Biomater 2017; 106:488-500. [DOI: 10.1002/jbm.b.33861] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Revised: 12/05/2016] [Accepted: 01/26/2017] [Indexed: 12/15/2022]
Affiliation(s)
- Eloísa Díaz-Moreno
- Division of Pediatric Surgery; University of Granada Hospital Complex; Granada Spain
- PhD Programme in Clinical Medicine and Public Health; University of Granada; Spain
| | | | - Víctor Carriel
- Department of Histology (Tissue Engineering Group); University of Granada; Spain
- Biosanitary Research Institute of Granada (ibs.GRANADA); Spain
| | - Miguel-Ángel Martín-Piedra
- Department of Histology (Tissue Engineering Group); University of Granada; Spain
- Biosanitary Research Institute of Granada (ibs.GRANADA); Spain
| | - María-del-Carmen Sánchez-Quevedo
- Department of Histology (Tissue Engineering Group); University of Granada; Spain
- Biosanitary Research Institute of Granada (ibs.GRANADA); Spain
| | - Ingrid Garzón
- Department of Histology (Tissue Engineering Group); University of Granada; Spain
- Biosanitary Research Institute of Granada (ibs.GRANADA); Spain
| | - Antonio Campos
- Department of Histology (Tissue Engineering Group); University of Granada; Spain
- Biosanitary Research Institute of Granada (ibs.GRANADA); Spain
| | - Ricardo Fernández-Valadés
- Division of Pediatric Surgery; University of Granada Hospital Complex; Granada Spain
- Department of Histology (Tissue Engineering Group); University of Granada; Spain
- Biosanitary Research Institute of Granada (ibs.GRANADA); Spain
| | - Miguel Alaminos
- Department of Histology (Tissue Engineering Group); University of Granada; Spain
- Biosanitary Research Institute of Granada (ibs.GRANADA); Spain
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22
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Wang S, Elliott GD. Synergistic Development of Biochips and Cell Preservation Methodologies: A Tale of Converging Technologies. CURRENT STEM CELL REPORTS 2017; 3:45-53. [PMID: 28966905 DOI: 10.1007/s40778-017-0074-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
PURPOSE OF THE REVIEW Over the past several decades, cryopreservation has been widely used to preserve cells during long term storage, but advances in stem cell therapies, regenerative medicine, and miniaturized cell-based diagnostics and sensors are providing new targets of opportunity for advancing preservation methodologies. The advent of microfluidics-based devices is an interesting case in which the technology has been used to improve preservation processing, but as the devices have evolved to also include cells, tissues, and simulated organs as part of the architecture, the biochip itself is a desirable target for preservation. In this review, we will focus on the synergistic co-development of preservation methods and biochip technologies, while identifying where the challenges and opportunities lie in developing methods to place on-chip biologics on the shelf, ready for use. RECENT FINDINGS Emerging studies are demonstrating that the cost of some biochips have been reduced to the extent that they will have high utility in point-of-care settings, especially in low resource environments where diagnostic capabilities are limited. Ice-free low temperature vitrification and anhydrous vitrification technologies will likely emerge as the preferred strategy for long-term preservation of bio-chips. SUMMARY The development of preservation methodologies for partially or fully assembled biochips would enable the widespread distribution of these technologies and enhance their application.
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Affiliation(s)
- Shangping Wang
- Department of Mechanical Engineering and Engineering Sciences, University of North Carolina at Charlotte, Charlotte, NC 28223
| | - Gloria D Elliott
- Department of Mechanical Engineering and Engineering Sciences, University of North Carolina at Charlotte, Charlotte, NC 28223
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23
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Decellularized GGTA1-KO pig heart valves do not bind preformed human xenoantibodies. Basic Res Cardiol 2016; 111:39. [DOI: 10.1007/s00395-016-0560-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Accepted: 05/03/2016] [Indexed: 10/21/2022]
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