ABC | Volume 113, Nº1, July 2019

Original Article Characterization of Decellularized Human Pericardium for Tissue Engineering and Regenerative Medicine Applications Luciana Wollmann, Paula Sus s, J oão Mendonça, Cesar Luzia, Andressa Schittini, George Willian Xavier da Ros a, Francisco Costa, Felipe F. Tuon Pontifícia Universidade Católica do Paraná, Curitiba, PR – Brazil Mailing Address: Felipe F. Tuon • Imaculada Conceição, 1155. Postal Code 80215-901, Curitiba, PR – Brazil E-mail: flptuon@gmail.com Manuscript received June 22, 2018, revised manuscript August 13, 2018, accepte September 19, 2018 DOI: 10.5935/abc.20190094 Abstract Background: Pericardium tissue allograft can be used for surgical repair in several procedures. One of the tissue engineering strategies is the process of decellularization. This process decreases immunogenic response, but it may modify the natural extracellular matrix composition and behavior. Objective: The aim of this study was to evaluate the effectiveness of cell removal, maintenance of extracellular matrix properties and mechanical integrity of decellularized human pericardium using a low concentration solution of sodium dodecyl sulfate. Methods: Decellularization was performed with sodiumdodecyl sulfate and ethylenediaminetetraacetic acid. Histological analysis, DNA quantification, evaluation of glycosaminoglycans and collagen were performed. Biomechanical assay was performed using tensile test to compare the decellularization effects on tissue properties of tensile strength, elongation and elastic modulus. P < 0.05 was considered significant. Results: There was reduction in visible nuclei present in pericardium tissue after decellularization, but it retained collagen and elastin bundles similar to fresh pericardium. The DNA contents of the decellularized pericardium were significantly reduced to less than 511.23 ± 120.4 ng per mg of dry weight (p < 0.001). The biomechanical assay showed no significant difference for fresh or decellularized tissue. Conclusion: The decellularization process reduces cell content as well as extracellular matrix components without changing its biomechanical properties. (Arq Bras Cardiol. 2019; 113(1):11-17) Keywords: Pericardium; Tissue Banks; Tissue Engineering/trends; Cell Separation; Glycosaminoglycans. Introduction Development of extracellular matrix-derived bioscaffolds has been highly desired for applications in tissue engineering and regenerative medicine. 1 These scaffolds can be obtained from a variety of allogeneic or xenogeneic tissue sources and from several different species. 2 However, biomaterial antigenicity represents the primary barrier to expanding the use of xenogeneic tissues in clinical practice. 3 Pericardium is a collagen-rich biological tissue containing glycoproteins and glycosaminoglycans 3 and is readily available, easy to handle, and pliable. Human pericardium can be used as a patch for heart surgeries 4 and non-heart surgeries (Peyronie’s disease, 4 glaucoma and corneal surgery, 5,6 to cover exposed scleral buckles 7 and oculoplastic surgery. 8 Human pericardium patch is a well-recognized material for cardiovascular repair. 4 The physicochemical features of autologous pericardium used for repair include fresh pericardium 9,10 and glutaraldehyde-treated pericardium. 11 However, the use of fresh autologous untreated pericardium can result in tissue retraction, thickening, fibrosis and loss of pliability 12 and the use of glutaraldehyde-treated autologous pericardium can result in calcification. 13 The main obstacle is the development of biocompatible and functional extracellular matrix-derived bioscaffold. The use of biological tissues increases the potential risks of pathogen transmission 14 and inflammatory or immunogenic response. 2,15 Decellularization techniques have been used to minimize these issues. 16 Tissue decellularization can be performed by using different protocols, detergent extraction or enzymatic extraction with hypotonic or hypertonic washings and physical (agitation, sonication, mechanical pressure or freeze-thawing) treatments. 2 The ideal decellularization method must remove all antigenic components (nucleic acids, cell membranes, cytoplasmic structures, lipids and soluble matrix) from the tissue without damaging extracellular matrix structure and integrity. 17,18 However, the decellularization process can modify the natural extracellular matrix composition, as well as mechanical and structural characteristics. 19 Furthermore, high levels of donor variability to naive ECM composition undoubtedly lead to different ECM fractional composition post-decellularization. Hence, ECM standardization as 11