1
|
Naso F, Colli A, Zilla P, Calafiore AM, Lotan C, Padalino MA, Sturaro G, Gandaglia A, Spina M. Correlations between the alpha-Gal antigen, antibody response and calcification of cardiac valve bioprostheses: experimental evidence obtained using an alpha-Gal knockout mouse animal model. Front Immunol 2023; 14:1210098. [PMID: 37426661 PMCID: PMC10327888 DOI: 10.3389/fimmu.2023.1210098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Accepted: 06/06/2023] [Indexed: 07/11/2023] Open
Abstract
Introduction Preformed antibodies against αGal in the human and the presence of αGal antigens on the tissue constituting the commercial bioprosthetic heart valves (BHVs, mainly bovine or porcine pericardium), lead to opsonization of the implanted BHV, leading to deterioration and calcification. Murine subcutaneous implantation of BHVs leaflets has been widely used for testing the efficacy of anti-calcification treatments. Unfortunately, commercial BHVs leaflets implanted into a murine model will not be able to elicit an αGal immune response because such antigen is expressed in the recipient and therefore immunologically tolerated. Methods This study evaluates the calcium deposition on commercial BHV using a new humanized murine αGal knockout (KO) animal model. Furtherly, the anti-calcification efficacy of a polyphenol-based treatment was deeply investigated. By using CRISPR/Cas9 approach an αGal KO mouse was created and adopted for the evaluation of the calcific propensity of original and polyphenols treated BHV by subcutaneous implantation. The calcium quantification was carried out by plasma analysis; the immune response evaluation was performed by histology and immunological assays. Anti-αGal antibodies level in KO mice increases at least double after 2 months of implantation of original commercial BHV compared to WT mice, conversely, the polyphenols-based treatment seems to effectively mask the antigen to the KO mice's immune system. Results Commercial leaflets explanted after 1 month from KO mice showed a four-time increased calcium deposition than what was observed on that explanted from WT. Polyphenol treatment prevents calcium deposition by over 99% in both KO and WT animals. The implantation of commercial BHV leaflets significantly stimulates the KO mouse immune system resulting in massive production of anti-Gal antibodies and the exacerbation of the αGal-related calcific effect if compared with the WT mouse. Discussion The polyphenol-based treatment applied in this investigation showed an unexpected ability to inhibit the recognition of BHV xenoantigens by circulating antibodies almost completely preventing calcific depositions compared to the untreated counterpart.
Collapse
Affiliation(s)
- Filippo Naso
- Biocompatibility Innovation Srl, Este, Padua, Italy
| | - Andrea Colli
- Cardiac Surgery Unit, Department of Surgical, Medical and Molecular Pathology and Critical Care, University of Pisa, Pisa, Italy
| | - Peter Zilla
- Christian Barnard Department of Cardiothoracic Surgery, Groote Schuur Hospital, University of Cape Town, Cape Town, South Africa
| | | | - Chaim Lotan
- Hadassah University Hospital - Cardiovascular Division, Ein Kerem, Jerusalem, Israel
| | - Massimo A. Padalino
- Pediatric and Congenital Cardiac Surgery Unit, Department of Cardiac, Thoracic and Vascular Sciences and Public Health, University of Padua, Padua, Italy
| | | | | | - Michele Spina
- Department of Biomedical Sciences, University of Padua, Padua, Italy
| |
Collapse
|
2
|
Melder RJ, Naso F, Nicotra F, Russo L, Vesely I, Tuladhar SR, Calafiore AM, Zilla P, Gandaglia A, Korossis S. Preventing extrinsic mechanisms of bioprosthetic degeneration using polyphenols. Eur J Cardiothorac Surg 2022; 63:6957091. [PMID: 36548449 DOI: 10.1093/ejcts/ezac583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 12/13/2022] [Accepted: 12/21/2022] [Indexed: 12/24/2022] Open
Abstract
OBJECTIVES the purpose of this study was to evaluate the impact of a polyphenols-based treatment on the extrinsic mechanisms responsible for early BHV degeneration. Structural degeneration can be driven by both extrinsic and intrinsic mechanisms. While intrinsic mechanisms have been associated with inherent biocompatibility characteristics of the BHV, the extrinsic ones have been reported to involve external causes, such as chemical, mechanical and hydrodynamic, responsible to facilitate graft damage. METHODS the chemical interaction and the stability degree between polyphenols and pericardial tissue were carefully evaluated. The detoxification of glutaraldehyde in commercial BHVs models as well as the protective effect from in-vivo calcification were taken into relevant consideration. Finally, the hydrodynamic and biomechanical features of the polyphenols-treated pericardial tissue were deeply investigated by pulse duplicator and stress-strain analysis. RESULTS the study demonstrated the durability of the polyphenols-based treatment on pericardial tissue and the stability of the bound polyphenols. The treatment improves glutaraldehyde stabilization's current degree, demonstrating a surprising in-vivo anti-calcific effect. It is able to make the pericardial tissue more pliable while maintaining the correct hydrodynamic characteristics. CONCLUSIONS the polyphenols treatment has proved to be a promising approach capable of acting simultaneously on several factors related to the premature degeneration of cardiac valve substitutes by extrinsic mechanisms.
Collapse
Affiliation(s)
| | | | - Francesco Nicotra
- University of Milano-Bicocca, Department of Biotechnology and Biosciences, Milan, Italy
| | - Laura Russo
- University of Milano-Bicocca, Department of Biotechnology and Biosciences, Milan, Italy.,CÚRAM, SFI Research Centre for Medical Devices, National University of Ireland Galway, Galway, Ireland
| | - Ivan Vesely
- Class III Medical Device Consulting, Maryland, USA
| | - Sugat R Tuladhar
- Department of Cardiothoracic, Transplantation and Vascular Surgery, Lower Saxony Centre for Biomedical Engineering, Implant Research and Development, Hannover Medical School, Hannover, Germany
| | | | - Peter Zilla
- Christian Barnard Department of Cardiothoracic Surgery, Groote Schuur Hospital, University of Cape Town, Cape Town, South Africa
| | | | - Sotiris Korossis
- Centre for Biological Engineering, Wolfson School of Mechanical, Electrical and Manufacturing Engineering, Loughborough University, Loughborough, Leicestershire, United Kingdom
| |
Collapse
|
3
|
Naso F, Gandaglia A. Can Heart Valve Decellularization Be Standardized? A Review of the Parameters Used for the Quality Control of Decellularization Processes. Front Bioeng Biotechnol 2022; 10:830899. [PMID: 35252139 PMCID: PMC8891751 DOI: 10.3389/fbioe.2022.830899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 01/31/2022] [Indexed: 11/13/2022] Open
Abstract
When a tissue or an organ is considered, the attention inevitably falls on the complex and delicate mechanisms regulating the correct interaction of billions of cells that populate it. However, the most critical component for the functionality of specific tissue or organ is not the cell, but the cell-secreted three-dimensional structure known as the extracellular matrix (ECM). Without the presence of an adequate ECM, there would be no optimal support and stimuli for the cellular component to replicate, communicate and interact properly, thus compromising cell dynamics and behaviour and contributing to the loss of tissue-specific cellular phenotype and functions. The limitations of the current bioprosthetic implantable medical devices have led researchers to explore tissue engineering constructs, predominantly using animal tissues as a potentially unlimited source of materials. The high homology of the protein sequences that compose the mammalian ECM, can be exploited to convert a soft animal tissue into a human autologous functional and long-lasting prosthesis ensuring the viability of the cells and maintaining the proper biomechanical function. Decellularization has been shown to be a highly promising technique to generate tissue-specific ECM-derived products for multiple applications, although it might comprise very complex processes that involve the simultaneous use of chemical, biochemical, physical and enzymatic protocols. Several different approaches have been reported in the literature for the treatment of bone, cartilage, adipose, dermal, neural and cardiovascular tissues, as well as skeletal muscle, tendons and gastrointestinal tract matrices. However, most of these reports refer to experimental data. This paper reviews the most common and latest decellularization approaches that have been adopted in cardiovascular tissue engineering. The efficacy of cells removal was specifically reviewed and discussed, together with the parameters that could be used as quality control markers for the evaluation of the effectiveness of decellularization and tissue biocompatibility. The purpose was to provide a panel of parameters that can be shared and taken into consideration by the scientific community to achieve more efficient, comparable, and reliable experimental research results and a faster technology transfer to the market.
Collapse
|
4
|
Naso F, Calafiore AM, Gaudino M, Zilla P, Haverich A, Colli A, Melder RJ, Gandaglia A. Polyphenols could be Effective in Exerting a Disinfectant-Like Action on Bioprosthetic Heart Valves, Counteracting Bacterial Adhesiveness. Cardiol Cardiovasc Med 2022; 6:487-492. [PMID: 36303878 PMCID: PMC9601395 DOI: 10.26502/fccm.92920287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND The incidence of infective endocarditis in patients with bioprosthetic heart valves is over 100 times that of the general population with S. aureus recognized as the causative organism in approximately 1/3 of cases. In this study, (1) the microbicidal and virucidal effect of a polyphenolic solution was carefully evaluated. The same solution was then adopted for the treatment of a commercial bioprosthetic heart valve model for (2) the assessment of inhibition of S. aureus adhesiveness. METHODS (1) the viability of 9 microorganisms strains (colony-forming units) and the infectivity degree of 3 viral strains (cellular infection capacity) were evaluated after suspension in the polyphenolic solution. (2) Leaflets from a treated and untreated commercial surgical valve model were incubated with a known concentration of S. aureus. After incubation, the leaflets were homogenized and placed in specific culture media to quantify the bacterial load. RESULTS (1) The polyphenolic solution proved to be effective in eliminating microorganisms strains guaranteeing the killing of at least 99.9%. The effectiveness is particularly relevant against M. chelonae (99.999%). (2) The polyphenol-based treatment resulted in the inhibition of the S. aureus adhesiveness by 96% concerning untreated samples. CONCLUSIONS The data suggest an interesting protective effect against infections and bacterial adhesiveness by a polyphenolic-based solution. Further studies will plan to extend the panel of microorganisms for the evaluation of the anti-adhesive effect; however, the use of optimized polyphenolic blends could lead to the development of new treatments capable to make transcatheter-valve substitutes more resistant to infection.
Collapse
Affiliation(s)
- Filippo Naso
- Biocompatibility Innovation SRL, Este, Padua, Italy
| | | | - Mario Gaudino
- Department of Cardiothoracic Surgery, Weill Cornell Medicine, New York, USA
| | - Peter Zilla
- Christian Barnard Department of Cardiothoracic Surgery, Groote Schuur Hospital, University of Cape Town, Cape Town, South Africa
| | - Axel Haverich
- Department of Cardiothoracic, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany
| | - Andrea Colli
- Cardiac Surgery Unit, Department of Surgical, Medical and Molecular Pathology and Critical Care, University of Pisa, Pisa, Italy
| | | | | |
Collapse
|
5
|
Naso F, Gandaglia A. Cover Image, Volume 25, Issue 1. Xenotransplantation 2018. [DOI: 10.1111/xen.12388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
6
|
Naso F, Gandaglia A. Different approaches to heart valve decellularization: A comprehensive overview of the past 30 years. Xenotransplantation 2017; 25. [PMID: 29057501 DOI: 10.1111/xen.12354] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 08/28/2017] [Accepted: 09/01/2017] [Indexed: 12/16/2022]
Abstract
Xenogeneic decellularized heart valve scaffolds have the potential to overcome the limitations of existing bioprosthetic heart valves that have limited duration due to calcification and tissue degeneration phenomena. This article presents a review of 30 years of decellularization approaches adopted in cardiovascular tissue engineering, with a focus on the use, either individually or in combination, of different detergents. The safety and efficacy of cell-removal procedures are specifically reported and discussed, as well as the structure and biomechanics of the treated extracellular matrix (ECM). Detergent residues within the ECM, production of hyaluronan fragments, safe removal of cellular debris, and the persistence of the alpha-Gal epitope after the decellularization treatments are of particular interest as parameters for the identification of the best tissue for the manufacture of bioprostheses. Special attention has also been given to key factors that should be considered in the manufacture of the next generation of xenogeneic bioprostheses, where tissues must retain the ability to be remodeled and to grow in weight along with body reshaping.
Collapse
Affiliation(s)
- Filippo Naso
- Biocompatibility Innovation Company, Este, Padova, Italy
| | | |
Collapse
|
7
|
Naso F, Stefanelli U, Buratto E, Lazzari G, Perota A, Galli C, Gandaglia A. Alpha-Gal Inactivated Heart Valve Bioprostheses Exhibit an Anti-Calcification Propensity Similar to Knockout Tissues. Tissue Eng Part A 2017; 23:1181-1195. [DOI: 10.1089/ten.tea.2016.0474] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Filippo Naso
- Biocompatibility Innovation, Medical Device Biocompatibility Laboratory, Padova, Italy
| | - Ugo Stefanelli
- Biocompatibility Innovation, Medical Device Biocompatibility Laboratory, Padova, Italy
| | - Edward Buratto
- Cardiac Surgery Unit, Royal Children's Hospital, Melbourne, Australia
- Department of Paediatrics, University of Melbourne, Melbourne, Australia
| | | | - Andrea Perota
- Avantea, Laboratory of Reproductive Technology, Cremona, Italy
| | - Cesare Galli
- Avantea, Laboratory of Reproductive Technology, Cremona, Italy
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
- Fondazione Avantea, Cremona, Italy
| | - Alessandro Gandaglia
- Biocompatibility Innovation, Medical Device Biocompatibility Laboratory, Padova, Italy
| |
Collapse
|
8
|
Di Liddo R, Aguiari P, Barbon S, Bertalot T, Mandoli A, Tasso A, Schrenk S, Iop L, Gandaglia A, Parnigotto PP, Conconi MT, Gerosa G. Nanopatterned acellular valve conduits drive the commitment of blood-derived multipotent cells. Int J Nanomedicine 2016; 11:5041-5055. [PMID: 27789941 PMCID: PMC5068475 DOI: 10.2147/ijn.s115999] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Considerable progress has been made in recent years toward elucidating the correlation among nanoscale topography, mechanical properties, and biological behavior of cardiac valve substitutes. Porcine TriCol scaffolds are promising valve tissue engineering matrices with demonstrated self-repopulation potentiality. In order to define an in vitro model for investigating the influence of extracellular matrix signaling on the growth pattern of colonizing blood-derived cells, we cultured circulating multipotent cells (CMC) on acellular aortic (AVL) and pulmonary (PVL) valve conduits prepared with TriCol method and under no-flow condition. Isolated by our group from Vietnamese pigs before heart valve prosthetic implantation, porcine CMC revealed high proliferative abilities, three-lineage differentiative potential, and distinct hematopoietic/endothelial and mesenchymal properties. Their interaction with valve extracellular matrix nanostructures boosted differential messenger RNA expression pattern and morphologic features on AVL compared to PVL, while promoting on both matrices the commitment to valvular and endothelial cell-like phenotypes. Based on their origin from peripheral blood, porcine CMC are hypothesized in vivo to exert a pivotal role to homeostatically replenish valve cells and contribute to hetero- or allograft colonization. Furthermore, due to their high responsivity to extracellular matrix nanostructure signaling, porcine CMC could be useful for a preliminary evaluation of heart valve prosthetic functionality.
Collapse
Affiliation(s)
- Rosa Di Liddo
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova; Foundation for Biology and Regenerative Medicine, Tissue Engineering and Signaling ONLUS
| | - Paola Aguiari
- Department of Cardiac, Thoracic and Vascular Sciences, University of Padova, Padova, Italy
| | - Silvia Barbon
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova; Foundation for Biology and Regenerative Medicine, Tissue Engineering and Signaling ONLUS
| | - Thomas Bertalot
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova
| | - Amit Mandoli
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova
| | - Alessia Tasso
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova
| | - Sandra Schrenk
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova
| | - Laura Iop
- Department of Cardiac, Thoracic and Vascular Sciences, University of Padova, Padova, Italy
| | - Alessandro Gandaglia
- Department of Cardiac, Thoracic and Vascular Sciences, University of Padova, Padova, Italy
| | - Pier Paolo Parnigotto
- Foundation for Biology and Regenerative Medicine, Tissue Engineering and Signaling ONLUS
| | - Maria Teresa Conconi
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova; Foundation for Biology and Regenerative Medicine, Tissue Engineering and Signaling ONLUS
| | - Gino Gerosa
- Department of Cardiac, Thoracic and Vascular Sciences, University of Padova, Padova, Italy
| |
Collapse
|
9
|
Martini P, Sales G, Brugiolo M, Gandaglia A, Naso F, De Pittà C, Spina M, Gerosa G, Chemello F, Romualdi C, Cagnin S, Lanfranchi G. Tissue-specific expression and regulatory networks of pig microRNAome. PLoS One 2014; 9:e89755. [PMID: 24699212 PMCID: PMC3974652 DOI: 10.1371/journal.pone.0089755] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Accepted: 01/23/2014] [Indexed: 12/19/2022] Open
Abstract
Background Despite the economic and medical importance of the pig, knowledge about its genome organization, gene expression regulation, and molecular mechanisms involved in physiological processes is far from that achieved for mouse and rat, the two most used model organisms in biomedical research. MicroRNAs (miRNAs) are a wide class of molecules that exert a recognized role in gene expression modulation, but only 280 miRNAs in pig have been characterized to date. Results We applied a novel computational approach to predict species-specific and conserved miRNAs in the pig genome, which were then subjected to experimental validation. We experimentally identified candidate miRNAs sequences grouped in high-confidence (424) and medium-confidence (353) miRNAs according to RNA-seq results. A group of miRNAs was also validated by PCR experiments. We established the subtle variability in expression of isomiRs and miRNA-miRNA star couples supporting a biological function for these molecules. Finally, miRNA and mRNA expression profiles produced from the same sample of 20 different tissue of the animal were combined, using a correlation threshold to filter miRNA-target predictions, to identify tissue-specific regulatory networks. Conclusions Our data represent a significant progress in the current understanding of miRNAome in pig. The identification of miRNAs, their target mRNAs, and the construction of regulatory circuits will provide new insights into the complex biological networks in several tissues of this important animal model.
Collapse
Affiliation(s)
- Paolo Martini
- Department of Biology, University of Padova, Padova, Italy; CRIBI Biotechnology Centre, University of Padova, Padova, Italy
| | - Gabriele Sales
- Department of Biology, University of Padova, Padova, Italy
| | - Mattia Brugiolo
- Department of Biology, University of Padova, Padova, Italy; CRIBI Biotechnology Centre, University of Padova, Padova, Italy
| | - Alessandro Gandaglia
- Department of Cardiac, Thoracic and Vascular Sciences, University of Padova, Padova, Italy
| | - Filippo Naso
- Department of Cardiac, Thoracic and Vascular Sciences, University of Padova, Padova, Italy
| | | | - Michele Spina
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Gino Gerosa
- Department of Cardiac, Thoracic and Vascular Sciences, University of Padova, Padova, Italy
| | | | | | - Stefano Cagnin
- Department of Biology, University of Padova, Padova, Italy; CRIBI Biotechnology Centre, University of Padova, Padova, Italy
| | - Gerolamo Lanfranchi
- Department of Biology, University of Padova, Padova, Italy; CRIBI Biotechnology Centre, University of Padova, Padova, Italy
| |
Collapse
|
10
|
Naso F, Gandaglia A, Bottio T, Tarzia V, Nottle MB, d'Apice AJF, Cowan PJ, Cozzi E, Galli C, Lagutina I, Lazzari G, Iop L, Spina M, Gerosa G. First quantification of alpha-Gal epitope in current glutaraldehyde-fixed heart valve bioprostheses. Xenotransplantation 2013; 20:252-61. [PMID: 23865597 DOI: 10.1111/xen.12044] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2012] [Accepted: 05/31/2013] [Indexed: 11/29/2022]
Abstract
BACKGROUND Glutaraldehyde fixation does not guarantee complete tissue biocompatibility in current clinical bioprosthetic heart valves (BHVs). Particularly, circulating anti-αGal human antibodies increase significantly from just 10 days after a BHV implantation. The inactivation of such epitope should be mandatory to meet the requirements for a perspectively safe clinical application; nevertheless, its quantitative assessment in commercially available BHVs has never been carried out. METHODS In this investigation, seven different models of BHVs were tested. The number of epitopes was determined with reference to a standard αGal source by an ELISA test. The presence of xenoantigen was subsequently confirmed by immunofluorescence analysis. Porcine tissue, knockout for the αGal epitopes, was used as negative control. RESULTS Epic™ valve was the only model among those tested, in which the αGal antigen appeared to be completely shielded. Composite Trifecta™ valve exhibited conflicting results: cusps of bovine pericardial tissue were devoid of reactive αGal epitopes, while the stent cover strip of porcine pericardium still maintained 30% of active antigens originally present in native tissue. All other tested BHVs express an αGal amount not significantly different from that exhibited by porcine Mosaic(®) valve (5.2 ± 0.6 × 10(10) each 10 mg of tissue). CONCLUSIONS For the first time, the quantitative evaluation of the αGal epitope in heart valve bioprostheses, already in clinical practice for about 40 yrs, was finally determined. Such quantification might provide indications of biocompatibility relevant for the selection of bioprosthetic devices and an increase in the confidence of the patient. It might become a major quality control tool in the production and redirection of future investigation in the quest for αGal-free long-lasting substitutes.
Collapse
Affiliation(s)
- Filippo Naso
- Department of Cardiac, Thoracic and Vascular Sciences, University of Padua, Padua, Italy.
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Gallo M, Bianco R, Bottio T, Naso F, Franci P, Zanella F, Perona G, Busetto R, Spina M, Gandaglia A, Gerosa G. Tissue-engineered heart valves: intra-operative protocol. J Cardiovasc Transl Res 2013; 6:660-1. [PMID: 23765554 DOI: 10.1007/s12265-013-9480-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Accepted: 05/31/2013] [Indexed: 10/26/2022]
Abstract
Tissue engineering of heart valves investigates the possibility to create a fully compatible and biomimetic graft able to provide host cell repopulation like the native living valve. Decellularized aortic and pulmonary valves and synthetic polymers have been used to promote the creation of a native-like scaffold suitable to be colonized by cells either in vitro, in dynamic bioreactors or in vivo using different animal models. The herein presented research provides the intra-operative protocol and details of surgical technique. Porcine aortic valve conduits were decellularized and implanted in the right ventricular outflow tract of Vietnamese pigs.
Collapse
Affiliation(s)
- Michele Gallo
- Division of Cardiac Surgery, Department of Cardiac, Thoracic and Vascular Science, University of Padua, Via Giustiniani 2, 35128, Padua, Italy.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
12
|
Naso F, Gandaglia A, Balboni P, Zanella F, Danesin R, Spina M, Gerosa G. Wet-priming extracorporeal membrane oxygenation device maintains sterility for up to 35 days of follow-up. Perfusion 2012; 28:208-13. [DOI: 10.1177/0267659112469641] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In emergency cases, rapid extracorporeal membrane oxygenation (ECMO) device initialization is able to drastically reduce the incidence of patient morbidity and/or mortality. Pre-assembled and ready-to-use ECMO circuits might save up to 30-60 critical minutes in patient management. Six ECMO circuits (Oxygenator D905 EOS with REVOLUTION™ pump and Sorin PTS) were assembled in the operating room in standard conditions and then placed at 37°C for 35 days in order to evaluate possible contamination and ingrowth of micro-organisms. Every 7 days after ECMO circuit assembly and wet-priming, samples of priming fluid were analyzed to verify the presence/absence of possible common contaminants ( Enterobacteriaceae, Staphylococcus aureus and fungi). Moreover, two supplementary circuits, used as positive controls, were deliberately inoculated with a known concentration of a Escherichia coli strain and prime samplings carried out at different time-points to determine bacterial growth rate. Sterility was maintained in the ECMO circuits for up to 35 days.
Collapse
Affiliation(s)
- F Naso
- Department of Cardiac, Thoracic and Vascular Science, University of Padova, Italy
| | - A Gandaglia
- Department of Cardiac, Thoracic and Vascular Science, University of Padova, Italy
| | - P Balboni
- Sorin Group Italia, Mirandola, Italy
| | - F Zanella
- Coordinator of Perfusionist Staff, Padova Hospital, Italy
| | - R Danesin
- Department of Chemical Process Engineering, University of Padova, Italy
| | - M Spina
- Department of Experimental Biomedical Science, University of Padova, Italy
| | - G Gerosa
- Department of Cardiac, Thoracic and Vascular Science, University of Padova, Italy
| |
Collapse
|
13
|
|
14
|
Gallo M, Naso F, Poser H, Rossi A, Franci P, Bianco R, Micciolo M, Zanella F, Cucchini U, Aresu L, Buratto E, Busetto R, Spina M, Gandaglia A, Gerosa G. Physiological performance of a detergent decellularized heart valve implanted for 15 months in Vietnamese pigs: surgical procedure, follow-up, and explant inspection. Artif Organs 2012; 36:E138-50. [PMID: 22512408 DOI: 10.1111/j.1525-1594.2012.01447.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
This study features the longest experimental follow-up for decellularized heart valves implanted in an animal model. Porcine aortic heart valves were decellularized according to a disclosed standardized method in which TRITON X-100 and sodium cholate (TRICOL) are used in succession, followed by a further treatment with the endonuclease Benzonase to completely remove the nucleic acid remnants. Experimental animals (n = 17), represented by Vietnamese pigs (VPs), received a decellularized aortic allograft as a substitute for the replacement of their right ventricular outflow tract. The surgical implantation of the TRICOL-treated aortic valve conduit was successful in 11 VPs, while perioperative or postoperative complications occurred in the remaining six animals. In the sham-operated group (n = 4), the native pulmonary root was excised and immediately reimplanted orthotopically in the same animal. Echocardiography demonstrated a satisfactory hemodynamic performance of the TRICOL-treated valves during follow-up as well as the absence of relevant leaflet alterations concerning thickness and motility or valve insufficiency. At explantation, macroscopic inspection of tissue-engineered heart valve conduits did not evidence calcifications and showed a decreased wall thickness, comparable to that of the reimplanted native pulmonary roots. Noteworthy, extended functional performance, recovery of DNA content, and active extracellular matrix precursor incorporation are apparently compatible with the properties of a living self-supporting substitute.
Collapse
Affiliation(s)
- Michele Gallo
- Department of Cardiac, Thoracic, and Vascular Science, University of Padova, 2 via Giustiniani, Padua, Italy
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Samouillan V, Dandurand J, Lacabanne C, Stella A, Gargiulo M, Degani A, Gandaglia A, Spina M. Analysis of the molecular mobility of collagen and elastin in safe, atheromatous and aneurysmal aortas. ACTA ACUST UNITED AC 2011; 60:58-65. [PMID: 22169773 DOI: 10.1016/j.patbio.2011.11.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2011] [Accepted: 10/30/2011] [Indexed: 11/19/2022]
Abstract
AIM OF THE STUDY In this study, we propose to use a thermal technique, Differential Scanning Calorimetry (DSC) to follow the evolution of elastin and collagen in safe and pathological cardiovascular tissues. PATIENTS AND METHODS The first part of this study deals with the analysis of the elastin network and associated proteins during ageing (from children to old persons) in aortic walls. The second part is devoted to the characterization of the collagenic phase in aneurysms. In both cases, physical data are correlated with biochemical analyses. RESULTS AND CONCLUSION For old persons aortas with atheromatous stades, elastin and associated proteins are found to interpenetrate to form a homogenous phase. Abdominal aortic aneurysms (AAA) are characterized by structural alterations of the aortic wall resulting from the degradation of elastic fibers and an increase of collagen/elastin ratio. Notable modifications are evidenced between collagen from control tissue and collagen from AAA, particularly concerning the thermal denaturation. Biochemical and thermal results are compatible with the increase of new collagen deposition and/or impairment of the collagen phase stability in the extracellular matrix of AAAs.
Collapse
Affiliation(s)
- V Samouillan
- Physique des polymères, BAT 3R1B2, institut Carnot, CIRIMAT UMR 5085, université Paul-Sabatier, 118, route de Narbonne, 31062 Toulouse cedex 9, France.
| | | | | | | | | | | | | | | |
Collapse
|
16
|
Gandaglia A, Huerta-Cantillo R, Comisso M, Danesin R, Ghezzo F, Naso F, Gastaldello A, Schittullo E, Buratto E, Spina M, Gerosa G, Dettin M. Cardiomyocytes in vitro adhesion is actively influenced by biomimetic synthetic peptides for cardiac tissue engineering. Tissue Eng Part A 2011; 18:725-36. [PMID: 22011064 DOI: 10.1089/ten.tea.2011.0254] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Scaffolds for tissue engineering must be designed to direct desired events such as cell attachment, growth, and differentiation. The incorporation of extracellular matrix-derived peptides into biomaterials has been proposed to mimic biochemical signals. In this study, three synthetic fragments of fibronectin, vitronectin, and stromal-derived factor-1 were investigated for the first time as potential adhesive sequences for cardiomyocytes (CMs) compared to smooth muscle cells. CMs are responsive to all peptides to differing degrees, demonstrating the existence of diverse adhesion mechanisms. The pretreatment of nontissue culture well surfaces with the (Arginine-Glycine-Aspartic Acid) RGD sequence anticipated the appearance of CMs' contractility compared to the control (fibronectin-coated well) and doubled the length of cell viability. Future prospects are the inclusion of these sequences into biomaterial formulation with the improvement in cell adhesion that could play an important role in cell retention during dynamic cell seeding.
Collapse
Affiliation(s)
- Alessandro Gandaglia
- Department of Cardiac, Thoracic and Vascular Science, University of Padova, Padova, Italy.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
17
|
Samouillan V, Delaunay F, Dandurand J, Merbahi N, Gardou JP, Yousfi M, Gandaglia A, Spina M, Lacabanne C. The use of thermal techniques for the characterization and selection of natural biomaterials. J Funct Biomater 2011; 2:230-48. [PMID: 24956305 PMCID: PMC4030942 DOI: 10.3390/jfb2030230] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2011] [Revised: 08/30/2011] [Accepted: 09/02/2011] [Indexed: 11/16/2022] Open
Abstract
In this paper we explore the ability of thermal analysis to check elastin and collagen integrity in different biomaterial applications. Differential Scanning Calorimetry (DSC) has been used to analyze the first and second order transitions of the biological macromolecules in the hydrated and dehydrated state. First, we report the characterization of control cardiovascular tissues such as pericardium, aortic wall and valvular leaflet. Their thermal properties are compared to pure elastin and pure collagen. Second, we present results obtained on two collagen rich tissues: pericardia with different chemical treatments and collagen with physical treatments. Finally, more complex cardiovascular tissues composed of elastin and collagen are analyzed and the effect of detergent treatment on the physical structure of collagen and elastin is brought to the fore.
Collapse
Affiliation(s)
- Valérie Samouillan
- Physique des Polymères, Institut Carnot CIRIMAT UMR5085, Université Paul Sabatier, 118 route de Narbonne, Bat 3R1B2, 31062 Toulouse Cedex, France.
| | - Florian Delaunay
- Physique des Polymères, Institut Carnot CIRIMAT UMR5085, Université Paul Sabatier, 118 route de Narbonne, Bat 3R1B2, 31062 Toulouse Cedex, France
| | - Jany Dandurand
- Physique des Polymères, Institut Carnot CIRIMAT UMR5085, Université Paul Sabatier, 118 route de Narbonne, Bat 3R1B2, 31062 Toulouse Cedex, France
| | - Nofel Merbahi
- LAPLACE, UMR CNRS 5213, Université Paul Sabatier, 118 Route de Narbonne, 31062 Toulouse Cedex 9, France
| | - Jean-Pierre Gardou
- LAPLACE, UMR CNRS 5213, Université Paul Sabatier, 118 Route de Narbonne, 31062 Toulouse Cedex 9, France
| | - Mohammed Yousfi
- LAPLACE, UMR CNRS 5213, Université Paul Sabatier, 118 Route de Narbonne, 31062 Toulouse Cedex 9, France
| | - Alessandro Gandaglia
- Dipartimento di Scienze Biomediche Sperimentali, Università di Padova, Viale Colombo 3, 35131 Padova, Italy
| | - Michel Spina
- Dipartimento di Scienze Biomediche Sperimentali, Università di Padova, Viale Colombo 3, 35131 Padova, Italy
| | - Colette Lacabanne
- Physique des Polymères, Institut Carnot CIRIMAT UMR5085, Université Paul Sabatier, 118 route de Narbonne, Bat 3R1B2, 31062 Toulouse Cedex, France
| |
Collapse
|
18
|
Naso F, Gandaglia A, Iop L, Spina M, Gerosa G. First quantitative assay of alpha-Gal in soft tissues: presence and distribution of the epitope before and after cell removal from xenogeneic heart valves. Acta Biomater 2011; 7:1728-34. [PMID: 21118731 DOI: 10.1016/j.actbio.2010.11.030] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2010] [Revised: 09/27/2010] [Accepted: 11/22/2010] [Indexed: 10/18/2022]
Abstract
Decellularized xenograft heart valves might be the ideal scaffolds for tissue engineered heart valves as the alternative to the currently used biological and mechanical prostheses. However, removal of the alpha-Gal epitope is a prerequisite to avoid hyperacute rejection of untreated xenograft material. The aim of this study was to develop an ELISA soft-tissue assay for alpha-Gal quantification in xenograft heart valves before and after a detergent-based (TriCol) or equivalent cell removal procedure. Leaflets from porcine valves were enzymatically digested to expose the epitope and reacted with the alpha-Gal monoclonal antibody M86 for its recognition. Rabbit erythrocytes were used as a reference for the quantification of alpha-Gal. Native aortic and pulmonary leaflets exhibited different epitope concentration: 4.33×10(11) vs. 7.12×10(11)/10 mg wet tissue (p<0.0001). Sampling of selected zones in native valves revealed a different alpha-Gal distribution within and among different leaflets. The pattern was consistent with immunofluorescence analysis and was unrelated to microvessel density distribution. After TriCol treatment alpha-Gal was no longer detectable in both pulmonary and aortic decellularized valves, confirming the ability of this method to remove both cells and alpha-Gal antigen. These results hold promise for a reliable quantitative evaluation of alpha-Gal in decellularized valves obtained from xenograft material for tissues engineering purposes. Additionally, this method is applicable to further evaluate currently used xenograft bioprostheses.
Collapse
|
19
|
Gandaglia A, Bagno A, Naso F, Spina M, Gerosa G. Cells, scaffolds and bioreactors for tissue-engineered heart valves: a journey from basic concepts to contemporary developmental innovations. Eur J Cardiothorac Surg 2010; 39:523-31. [PMID: 21163670 DOI: 10.1016/j.ejcts.2010.07.030] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2010] [Revised: 07/16/2010] [Accepted: 07/26/2010] [Indexed: 11/24/2022] Open
Abstract
The development of viable and functional tissue-engineered heart valves (TEHVs) is a challenge that, for almost two decades, the scientific community has been committed to face to create life-lasting prosthetic devices for treating heart valve diseases. One of the main drawbacks of tissue-based commercial substitutes, xenografts and homografts, is their lack of viability, and hence failure to grow, repair, and remodel. In adults, the average bioprostheses life span is around 13 years, followed by structural valve degeneration, such as calcification; in pediatric, mechanical valves are commonly used instead of biological substitutes, as in young patients, the mobilization of calcium, due to bone remodeling, accelerates the calcification process. Moreover, neither mechanical nor bioprostheses are able to follow children's body growth. Cell seeding and repopulation of acellular heart valve scaffolds, biological and polymeric, appears as a promising way to create a living valve. Biomechanical stimuli have significant impact on cell behavior including in vitro differentiation, and physiological hemodynamic conditioning has been found to promote new tissue development. These concepts have led scientists to design bioreactors to mimic the in vivo environment of heart valves. Many different types of somatic and stem cells have been tested for colonizing both the surface and the core of the valve matrix but controversial results have been achieved so far.
Collapse
Affiliation(s)
- Alessandro Gandaglia
- Department of Cardiac, Thoracic and Vascular Sciences, University of Padova, Via Giustiniani 2, 35128 Padova, Italy.
| | | | | | | | | |
Collapse
|
20
|
Samouillan V, Dandurand J, Lacabanne C, Stella A, Gargiulo M, Degani A, Gandaglia A, Spina M. Characterization of aneurysmal aortas by biochemical, thermal, and dielectric techniques. J Biomed Mater Res A 2010; 95:611-9. [DOI: 10.1002/jbm.a.32835] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
21
|
Bottio T, Tarzia V, Dal Lin C, Buratto E, Rizzoli G, Spina M, Gandaglia A, Naso F, Gerosa G. The changing hydrodynamic performance of the decellularized intact porcine aortic root: considerations on in-vitro testing. J Heart Valve Dis 2010; 19:485-491. [PMID: 20845897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
BACKGROUND AND AIM OF THE STUDY The most effective method for decellularization of the intact porcine aortic root remains controversial. Additionally, the hydrodynamic effect that such treatment may have on aortic roots has never been previously investigated. The study aim was to compare the in-vitro hydrodynamic performances of intact porcine aortic roots, both before and after decellularization treatment. METHODS Fifteen fresh porcine aortic roots were tested in the aortic chamber of the Sheffield pulse duplicator (SPD). For study purposes, the roots were first sutured to a silicone aortic root and then hydrodynamically tested. After in-vitro testing, the fresh porcine aortic roots, while still fixed within the silicone root, were decellularized according to various protocols (TRI-COL, TRI-DOC, sodium dodecyl sulfate (SDS) 0.03%, and SDS 0.1%). After decellularization, the valve roots were re-tested, adopting identical testing conditions. Forward flow pressure drop, closing leakage volumes, effective orifice area (EOA), and stroke work loss were each monitored. Three roots, used as a control group, were tested in identical fashion before and after storage (without decellularization) for comparative purposes. RESULTS The TRI-COL- and TRI-DOC-treated porcine aortic roots showed significantly lower transvalvular gradients, lower stroke work loss, lower valve resistance, and higher EOA than fresh intact porcine roots. In contrast, SDS 0.1%-treated porcine aortic roots showed opposing results, with the transvalvular gradients, stroke work loss and valve resistance each higher, and the EOA lower, than pre-treatment values. SDS 0.03% treatment had no significant effect on the hydrodynamic performance. After decellularization in all treatment groups, the diastolic parameters, total regurgitant volume and valve closing volume were each non-significantly increased. The aortic roots used as a control group showed similar results before and after storage. CONCLUSION Based on these results using the SPD, all treatments except for SDS 0.03% modified the systolic and diastolic functions of intact porcine aortic roots.
Collapse
Affiliation(s)
- Tomaso Bottio
- Cardiovascular Institute, University of Padova, Italy.
| | | | | | | | | | | | | | | | | |
Collapse
|
22
|
Iop L, Renier V, Naso F, Piccoli M, Bonetti A, Gandaglia A, Pozzobon M, Paolin A, Ortolani F, Marchini M, Spina M, De Coppi P, Sartore S, Gerosa G. The influence of heart valve leaflet matrix characteristics on the interaction between human mesenchymal stem cells and decellularized scaffolds. Biomaterials 2009; 30:4104-16. [PMID: 19481252 DOI: 10.1016/j.biomaterials.2009.04.031] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2009] [Accepted: 04/21/2009] [Indexed: 10/20/2022]
Abstract
The potential for in vitro colonization of decellularized valves by human bone marrow mesenchymal stem cells (hBM-MSCs) towards the anisotropic layers ventricularis and fibrosa and in homo- vs. heterotypic cell-ECM interactions has never been investigated. hBM-MSCs were expanded and characterized by immunofluorescence and FACS analysis. Porcine and human pulmonary valve leaflets (p- and hPVLs, respectively) underwent decellularization with Triton X100-sodium cholate treatment (TRICOL), followed by nuclear fragment removal. hBM-MSCs (2x10(6) cells/cm(2)) were seeded onto fibrosa (FS) or ventricularis (VS) of decellularized PVLs, precoated with FBS and fibronectin, and statically cultured for 30 days. Bioengineered PVLs revealed no histopathological features but a reconstructed endothelium lining and the presence of fibroblasts, myofibroblasts and SMCs, as in the corresponding native leaflet. The two valve layers behaved differently as regards hBM-MSC repopulation potential, however, with a higher degree of 3D spreading and differentiation in VS than in FS samples, and with enhanced cell survival and colonization effects in the homotypic ventricularis matrix, suggesting that hBM-MSC phenotypic conversion is strongly influenced in vitro by the anisotropic valve microstructure and species-specific matching between extracellular matrix and donor cells. These findings are of particular relevance to in vivo future applications of valve tissue engineering.
Collapse
Affiliation(s)
- Laura Iop
- Department of Cardiologic, Thoracic and Vascular Sciences, School of Medicine, University of Padua, Via Giustiniani, 2 - I-35128 Padua, Italy.
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
23
|
Spina M, Ortolani F, El Messlemani A, Gandaglia A, Bujan J, Garcia-Honduvilla N, Vesely I, Gerosa G, Casarotto D, Petrelli L, Marchini M. Isolation of intact aortic valve scaffolds for heart-valve bioprostheses: extracellular matrix structure, prevention from calcification, and cell repopulation features. J Biomed Mater Res A 2004; 67:1338-50. [PMID: 14624521 DOI: 10.1002/jbm.a.20025] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Extracellular matrix (ECM) scaffolds isolated from valvulated conduits can be useful in developing durable bioprostheses by tissue engineering provided that anatomical shape, architecture, and mechanical properties are preserved. As evidenced by SEM, intact scaffolds were derived from porcine aortic valves by the combined use of Triton X-100 and cholate (TRI-COL) or N-cetylpyridinium (CPC) and subsequent nucleic acid removal by nuclease. Both treatments were effective in removing most cells and all the cytomembranes, with preservation of (1) endothelium basal membranes, (2) ECM texture, including the D-periodical interaction of small proteoglycans with normally D-banded collagen fibrils, and (3) mechanical properties of the treated valves. Ultrastructural features agreed with DNA, hexosamine, and uronic acid biochemical estimations. Calcification potential, assessed by a 6-week rat subdermal model, was significantly reduced by TRI-COL/nuclease treatment. This was not true for CPC only, despite better proteoglycan preservation, suggesting that nucleic acids also are involved in calcification onset. Human fibroblasts, used to repopulate TRI-COL samples, formed mono- or multilayers on surfaces, and groups of cells also were scattered within the valve leaflet framework. A biocompatible scaffolds of this kind holds promise for production of durable valve bioprostheses that will be able to undergo probable turnover and/or remodeling by repopulating recipient cells.
Collapse
Affiliation(s)
- M Spina
- Department of Experimental Biomedical Sciences, University of Padova, Viale G, Colombo 3, I - 35121 Padova, Italy.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
24
|
Ortolani F, Tubaro F, Petrelli L, Gandaglia A, Spina M, Marchini M. Copper retention, calcium release and ultrastructural evidence indicate specific Cuprolinic Blue uptake and peculiar modifications in mineralizing aortic valves. Histochem J 2002; 34:41-50. [PMID: 12365799 DOI: 10.1023/a:1021347909622] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Previously, reactions with copper phthalocyanines at 0.05 M critical electrolyte concentration were found to cause demineralization in calcifying porcine aortic valves after subdermal implantation in rat, as well as simultaneous visualization of peculiar phthalocyanine-positive layers around cells and cell-derived matrix vesicles. In the present investigation, an appraisal was made of the mechanism and specificity of reactions with Cuprolinic Blue by comparing quantitatively calcium release and copper retention by calcified aortic valves reacted with this phthalocyanine under different critical electrolyte concentration conditions, and the corresponding ultrastructural patterns. It was found that (i) decalcifying properties are inversely proportional to salt molarity; (ii) reactivity to Cuprolinic Blue is critical electrolyte concentration-dependent, since the greatest copper retention occurred in 0.05 M critical electrolyte concentration Cuprolinic Blue-reacted samples, the only ones that also exhibited phthalocyanine-positive layers; (iii) the appearance of phthalocyanine-positive layers depends on Cuprolinic Blue uptake, revealing pericellular clustering of calcium-binding, anionic molecules; and (iv) minor Cuprolinic Blue uptake occurs by residual proteoglycans which still remain in the extracellular matrix after 6-week-long subdermal implantation. The present results indicate that this method is appropriate for the study of mineralized tissues and illustrate peculiar tissue modifications occurring at least in the experimental conditions used here.
Collapse
Affiliation(s)
- F Ortolani
- Department of Medical and Morphological Research, University of Udine, Italy
| | | | | | | | | | | |
Collapse
|