A Method for Fabricating Tissue-Specific Extracellular Matrix Blocks From Decellularized Tissue Powders.

Decellularized tissues retain the extracellular matrix (ECM), shape, and composition that are unique to the source tissue. Previous studies using decellularized tissue lysates and powders have shown that tissue-specific ECM plays a key role in cellular function and wound healing. However, creating decellularized tissues composed of tissue-specific ECM with customizable shapes and structures for use as scaffolding materials remains challenging.

Preparation, physico-biochemical characterization, and proteomic analysis of highly transparent corneal extracellular matrices for lamellar keratoplasty and tissue-engineered cornea construction.

Corneal opacity and deformation, which often require corneal transplantation for treatment, are among the leading causes of monocular blindness. To restore corneal clarity and integrity, there is a need for an artificial stroma that not only matches the transparency of donated human cornea but also effectively integrates to the corneal tissue. In this study, a transparent decellularized cornea was successfully developed using the high hydrostatic pressure method with processing conditions optimized for corneal decellularization.

Fibrin Hydrogel Layer-Anchored Pericardial Matrix Prevents Epicardial Adhesion in the Severe Heart Adhesion-Induced Miniature Pig Model.

Postoperative adhesion is a very common and serious complication that occurs frequently in cardiac surgery. The purpose of this study was to evaluate the efficacy of a fibrin hydrogel layer-anchored decellularized pericardial matrix in preventing pericardial adhesions in a miniature pig model with a myocardial injury. Fibrin hydrogel layer-anchored decellularized pericardial matrix was prepared by spraying a mixture of fibrinogen and thrombin on a fibrinogen-doped decellularized pericardium.

4-Arm PEG-Functionalized Decellularized Pericardium for Effective Prevention of Postoperative Adhesion in Cardiac Surgery.

Postoperative adhesions are a very common and serious complication in cardiac surgery, and the development of an effective anti-adhesion membrane showing resistance to the physical stimulus generated by the pulsation of the heart is desirable. In this study, an anti-adhesion material was developed through amine coupling between decellularized bovine pericardia (dBPCs) and 4-arm poly(ethylene glycol) succinimidyl glutarate (4-arm PEG-NHS) for the postoperative care of cardiac surgical patients. The efficacy of the 4-arm PEG-functionalized dBPCs in the prevention of adhesions after cardiac surgery was investigated in a rabbit heart adhesion model.

In vivo recellularization of xenogeneic vascular grafts decellularized with high hydrostatic pressure method in a porcine carotid arterial interpose model.

Autologous vascular grafts are widely used in revascularization surgeries for small caliber targets. However, the availability of autologous conduits might be limited due to prior surgeries or the quality of vessels. Xenogeneic decellularized vascular grafts from animals can potentially be a substitute of autologous vascular grafts.

Introduction of Cells into Porous Poly-l-Lactic Acid Scaffolds Using Impregnation Techniques.

Porous materials containing cells-prepared via cell seeding on scaffolds or gelation of cell-containing solutions-have been widely studied to investigate tissue regeneration and three-dimensional cultures. However, these methods cannot introduce cells into porous materials that have low water absorption or scaffolds that require cytotoxic solvents or processes for their production. In this study, first, three different impregnation treatments conditions (vacuum, pressure, and vacuum pressure impregnation: VPI) were applied to cell suspensions to evaluate the effect of each treatment on cells.

Preparation of gradient-type biological tissue-polymer complex for interlinking device.

The aim of this study was to investigate the monomer absorption behavior of decellularized dermis and prepare a gradient-type decellularized dermis-polymer complex. Decellularized dermis was prepared using sodium dodecyl sulfate, and its monomer absorption behavior was investigated using three types of hydrophobic monomer with different surface free energies. The results show that monomer absorption depends strongly on the tissue structure, regardless of the surface free energy, and the amount of absorbed monomer can be increased by sonication.

PLA-Collagen Composite Scaffold Fabrication by Vacuum Pressure Impregnation.

Composite scaffolds are made by various methods, such as copolymerization, freeze gelation, and thermally induced phase separation, which can compound materials with different properties using solvents and heat. However, it is difficult to compound solvents and heat-sensitive materials such as natural polymers. In this study, we investigated a vacuum pressure impregnation (VPI) method for creating a composite of natural polymers.

Re-epithelialization and remodeling of decellularized corneal matrix in a rabbit corneal epithelial wound model.

This study investigated the in vivo correlation between re-epithelialization and remodeling of a decellularized corneal matrix prepared by a high-hydrostatic pressure (HHP) method in rabbits. Decellularized corneal matrices were transplanted in a 6-mm-diameter recipient corneal interlamellar pocket with a 2 mm epithelial defect. The time course of graft status in rabbits was examined daily for 6 months by biomicroscopy and scored for clarity and re-epithelialization, after which the rabbits were sacrificed for histological analysis.

A fibrin-coated pericardial extracellular matrix prevented heart adhesion in a rat model.

As most surgical treatments pose a risk of tissue adhesion, methods to prevent adhesion are needed across various surgical fields. In this study, we investigated the use of a decellularized pericardium with fibrin glue to prevent rat heart adhesion. Porcine pericardia were decellularized by a high-hydrostatic pressure method.

[Rabbit Model for Evaluation of Anti-adhesive Materials after Open Heart Surgery].

Surgical trauma to the pericardial mesothelium during open heart procedures has formation of fibrovascular adhesions. Surgeons are confronted with cardiac adhesions, leading to an increased surgical risk such as intractable bleeding and possible catastrophic hemorrhage. In order to solve the problem, the anti-adhesion membrane has been developed and used.

Evaluation of small-diameter vascular grafts reconstructed from decellularized aorta sheets.

Following small-diameter vascular grafting, blood vessels fail to retain excellent antithrombotic function and therefore require application of antithrombogenic drugs. We have previously reported early attachment of endothelial cells to the luminal surface of high hydrostatic pressure (HHP)-decellularized arteries after transplantation. In addition, the graft retained antithrombotic function by endothelialization and remained open for several weeks.

[New Intracoronary Shunt Cannula in Off-pump Coronary Artery Bypass Grafting].

In off-pump coronary artery bypass grafting(OPCAB), a bloodless operative field has great influence on the quality of anastomosis. In addition, maintenance of distal coronary flow during anastomosis stabilizes hemodynamics. We introduced a new intracoronary shunt cannula, Mini Shunt Pro (MSP).

Histological structure affects recellularization of decellularized arteries.

Decellularized arteries were prepared to evaluate the in vivo recellularization of biological material after implantation. Porcine aortas and radial arteries were decellularized using high-hydrostatic pressure to form materials with histologically-different structures. Successful removal of cells from decellularized arteries was evaluated by hematoxylin-eosin staining and measurement of residual DNA.

Ultrastructural analysis of the decellularized cornea after interlamellar keratoplasty and microkeratome-assisted anterior lamellar keratoplasty in a rabbit model.

The decellularized cornea has received considerable attention for use as an artificial cornea. The decellularized cornea is free from cellular components and other immunogens, but maintains the integrity of the extracellular matrix. However, the ultrastructure of the decellularized cornea has yet to be demonstrated in detail.

Corneal Regeneration by Deep Anterior Lamellar Keratoplasty (DALK) Using Decellularized Corneal Matrix.

The purpose of this study is to demonstrate the feasibility of DALK using a decellularized corneal matrix obtained by HHP methodology. Porcine corneas were hydrostatically pressurized at 980 MPa at 10°C for 10 minutes to destroy the cells, followed by washing with EGM-2 medium to remove the cell debris. The HHP-treated corneas were stained with H-E to assess the efficacy of decellularization.

Decellularized porcine aortic intima-media as a potential cardiovascular biomaterial.

Objectives: The aim of this research is to investigate the histological and mechanical properties of decellularized aortic intima-media, a promising cardiovascular biomaterial.

Methods: Porcine aortic intima-media was decellularized using two methods: high hydrostatic pressurization (HHP) and sodium dodecyl sulphate (SDS). The histological properties were characterized using haematoxylin and eosin staining and Elastica van Gieson staining.

Fabrication of a heparin-PVA complex hydrogel for application as a vascular access.

A high hydrostatic pressure method, which can apply over 600 MPa pressure was employed for preparing a hydrogel of poly(vinyl alcohol) (PVA) loaded with heparin. The aim of this study was to fabricate a heparin-PVA hydrogel conduit and evaluate its potential for vascular access. Heparin-PVA complex hydrogel showed suppressed heparin release and prevented clot formation, depending on the molecular weight of the PVA.

Application of a vacuum pressure impregnation technique for rehydrating decellularized tissues.

Most of the clinically available decellularized tissues are preserved in a freeze-dried state. Freeze-dried (FD) tissues can be preserved for long term, although a rehydration process is necessary before use. Currently, an immersion method is most commonly used in clinical procedures, but it is difficult for complicated and thick structure tissue rehydration.

Porcine radial artery decellularization by high hydrostatic pressure.

Many types of decellularized tissues have been studied and some have been commercially used in clinics. In this study, small-diameter vascular grafts were made using HHP to decellularize porcine radial arteries. One decellularization method, high hydrostatic pressure (HHP), has been used to prepare the decellularized porcine tissues.

Preparation of a Nanoscaled Poly(vinyl alcohol)/Hydroxyapatite/DNA Complex Using High Hydrostatic Pressure Technology for In Vitro and In Vivo Gene Delivery.

Our previous research showed that poly(vinyl alcohol) (PVA) nanoparticles incorporating DNA with hydrogen bonds obtained by high hydrostatic pressurization are able to deliver DNA without any significant cytotoxicity. To enhance transfection efficiency of PVA/DNA nanoparticles, we describe a novel method to prepare PVA/DNA nanoparticles encapsulating nanoscaled hydroxyapatites (HAps) prepared by high hydrostatic pressurization (980 MPa), which is designed to facilitate endosomal escape induced by dissolving HAps in an endosome. Scanning electron microscopic observation and dynamic light scattering measurement revealed that HAps were significantly encapsulated in PVA/HAp/DNA nanoparticles.

The effect of decellularized bone/bone marrow produced by high-hydrostatic pressurization on the osteogenic differentiation of mesenchymal stem cells.

Decellularized bone/bone marrow was prepared to provide a microenvironment mimicking that of the bone marrow for three-dimensional culture in vitro. Bone/bone marrows were hydrostatically pressed at 980 MPa at 30 °C for 10 min to dismantle the cells. Then, they were washed with EGM-2 and further treated in an 80% EtOH to remove the cell debris and lipid, respectively.

Effect of treatment temperature on collagen structures of the decellularized carotid artery using high hydrostatic pressure.

Decellularized tissues have attracted a great deal of attention as regenerating transplantation materials. A decellularizing method based on high hydrostatic pressure (HHP) has been developed, and the preparation of many types of decellularized tissues has been investigated, including aorta, cornea, and dermis. The preparation of a small-diameter vascular graft was studied using a carotid artery from the viewpoint of collagen denaturation and leakage.

Engineering a collagen matrix that replicates the biological properties of native extracellular matrix.

In this study, we aimed to replicate the function of native tissues that can be used in tissue engineering and regenerative medicine. The key to such replication is the preparation of an artificial collagen matrix that possesses a structure resembling that of the extracellular matrix. We, therefore, prepared a collagen matrix by fibrillogenesis in a NaCl/Na(2)HPO(4) aqueous solution using a dialysis cassette and investigated its biological behavior in vitro and in vivo.