Purpose The main purpose of this investigation was to determine an efficient whole-organ decellularization protocol of a humansized uterus and evaluate the in vivo properties of the bioscaffold. Methods Twenty-four ovine uteri were included in this investigation and were decellularized by three different protocols (n 6). We performed histopathological and immunohistochemical evaluations, 4,6-diamidino-2-phenylindole (DAPI) staining, DNA quantification, MTT assay, scanning electron microscopy, biomechanical studies, and CT angiography to characterize the scaffolds. The optimized protocol was determined, and patches were grafted into the uterine horns of eight female Wistar rats. The grafts were extracted after 10 days; the opposite horns were harvested to be evaluated as controls.Results Protocol III (perfusion with 0.25% and 0.5% SDS solution and preservation in 10% formalin) was determined as the optimized method with efficient removal of the cellular components while preserving the extracellular matrix. Also, the bioscaffolds demonstrated native-like biomechanical, structural, and vascular properties. Histological and immunohistochemical evaluations of the harvested grafts confirmed the biocompatibility and recellularization potential of bioscaffolds. Also, the grafts demonstrated higher positive reaction for CD31 and Ki67 markers compared with the control samples which indicated eminent angiogenesis properties and proliferative capacity of the implanted tissues. Conclusions This investigation introduces an optimized protocol for whole-organ decellularization of the human-sized uterus with native-like characteristics and a prominent potential for regeneration and angiogenesis which could be employed in in vitro and in vivo studies. To the best of our knowledge, this is the first study to report biomechanical properties and angiographic evaluations of a large animal uterine scaffold.

Aim: The aim of this study was to evaluate the efficacy of tissue-engineered amniotic membrane (AM) in the treatment of myocardial infarction lesions. Materials & methods: 20 rats were subjected to coronary arterial ligation in order to induce myocardial infarction injury. Decellularized human AMs were seeded with 2 × 105 adipose-derived mesenchymal stem cells and were implanted in the infarcted hearts. Results & conclusion: Histological and immunohistochemical evaluations indicated the regeneration of cardiomyocytes and reduction of inflammation and fibrosis in the patch-implanted group compared with a control group, 14 days after the surgery. Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate biotin nick-end labeling assay was suggestive for apoptosis reduction in the patch-implanted specimens. This study suggested that human AM can be developed into a novel treatment for treating postmyocardial infarction.

The aim of this study was to determine an efficient whole-organ decellularisation protocol of a human-sized testis by perfusion through the testicular arteries. In the first step of this study, we determined the most efficient detergent agent, whereas the second phase delineated the optimal time required for the decellularisation process. Initially sheep testes were decellularised by one of three different detergent agents: sodium dodecyl sulphate (SDS), Triton X-100 and trypsin-ethylenediamine tetraacetic acid (EDTA) solutions, each perfused for 6h. In the second phase, the selected detergent agent was applied for different time periods. A total number of 20 organs were processed during this investigation. The efficacy of the decellularisation process and the preservation of the extracellular matrix components and structure were evaluated by histopathological examinations, 4′,6′-diamidino-2-phenylindole (DAPI) staining, DNA quantification, hydroxyproline measurement, magnetic resonance imaging and scanning electron microscopy. Organ perfusion with 1% SDS solution for 6 to 8h demonstrated the most desirable outcomes regarding decellularisation and extracellular matrix preservation. The 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide (MTT) assay was used to determine the toxicity of the scaffold and its potential for further application in tissue-engineering investigations. This investigation introduces an efficient method to produce a three-dimensional testicular bio-scaffold resembling the properties of the native organ that could be employed in tissue-engineering studies.

Myocardial infarction (MI) is a major cause of mortality and morbidity in industrialized societies. Myocardial tissue engineering is an alternative and promising approach for substituting injured myocardium through development and seeding of appropriate scaffolds. In this study, we investigated the efficacy of using an acellular pericardium to deliver autologous mesenchymal stem cells (MSCs) to the infarcted site for regeneration of the myocardium. MI was induced in two groups of rats; G1 or MI group, and G2 or patch-implanted group. In G2 group, rats had undergone transplantation of a pericardial patch which was previously seeded with adipose tissue derived MSCs. To evaluate the efficacy of the pericardial patches, biopsies were taken one month after transplantation. In order to evaluate the extent of regeneration, inflammation and fibrosis, histopathological investigations including hematoxylin and eosin (H&E), Sirius Red and trichrome staining were performed. In addition, immunohistochemical investigations by Desmin as well as CD68, CD45 and CD34 antibodies were performed. Furthermore, Tunnel assay was performed to detect the extent of apoptosis. H&E assessments of biopsies from the patch-implanted group confirmed presence of pre-seeded pericardium containing MSCs along with neo-vessels. Immunohistochemical assessments demonstrated higher number of CD34 positive cells and Desmin-positive cells in the patch implanted group (p < 0.05); these findings are suggestive of cardiomyocyte regeneration in G2 rats. This study demonstrates the advantages of application of natural acellular scaffolds as cell delivery devices and it emphasizes neovascularization following this approach. However, further investigations are required to analyze long-term cardiac function in recipients. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 2670-2678, 2018.