Preconditioning process for dermal tissue decellularization using electroporation with sonication.

Decellularization to produce bioscaffolds composed of the extracellular matrix (ECM) uses enzymatic, chemical and physical methods to remove antigens and cellular components from tissues. Effective decellularization methods depend on the characteristics of tissues, and in particular, tissues with dense, complex structure and abundant lipid content are difficult to completely decellularize. Our study enables future research on the development of methods and treatments for fabricating bioscaffolds via decellularization of complex and rigid skin tissues, which are not commonly considered for decellularization to date as their structural and functional characteristics could not be preserved after severe decellularization.

Pulsed Electrical Stimulation Enhances Consistency of Directional Migration of Adipose-Derived Stem Cells.

Electrical stimulation is a well-known strategy for regulating cell behavior, both in pathological and physiological processes such as wound healing, tissue regeneration, and embryonic development. Electrotaxis is the directional migration of cells toward the cathode or anode when subjected to electrical stimulation. In this study, we investigated the conditions for enhanced directional migration of electrically stimulated adipose-derived stem cells (ADSCs) during prolonged culture, using a customized agar-salt electrotaxis chamber.

A collagen-AS/εPLL bilayered artificial substitute regulates anti-inflammation and infection for initial inflamed wound healing.

Despite the development of advanced tissue engineering substitutes, inflammation is still a significant problem that can arise from inflamed burn injuries, chronic wounds, or microbial diseases. Although topical wound dressing accelerates healing by minimizing or preventing the consequences of skin inflammation, there remains a need for the development of a novel substitute scaffold that can effectively eliminate immoderate inflammation and infection in the initial phase of the healing meachanism. In this study, an artificial skin substitute scaffold fabricated with asiaticoside (AS) and epsilon-poly-L-lysine (εPLL) was prepared.

Sterilization of sealed PVDF pouches containing decellularized scaffold by electrical stimulation.

A terminal sterilization process for tissue engineering products, such as allografts and biomaterials is necessary to ensure complete removal of pathogenic microorganisms such as the bacteria, fungi, and viruses. However, it can be difficult to sterilize allografts and artificial tissue models packaged in wet conditions without deformation. In this study, we investigated the sterilization effects of electrical stimulation (ES) and assessed its suitability by evaluating sterility assurance levels in pouches at a constant current.

An effective method to generate controllable levels of ROS for the enhancement of HUVEC proliferation using a chlorin e6-immobilized PET film as a photo-functional biomaterial.

Reactive oxygen species (ROS) are byproducts of cellular metabolism; they play a significant role as secondary messengers in cell signaling. In cells, high concentrations of ROS induce apoptosis, senescence, and contact inhibition, while low concentrations of ROS result in angiogenesis, proliferation, and cytoskeleton remodeling. Thus, controlling ROS generation is an important factor in cell biology.

Asiaticoside and polylysine-releasing collagen complex for effectively reducing initial inflammatory response using inflamed induced in vitro model.

Inflammation is a significant clinical problem that can arise from full-thickness wounds or burn injuries or microbial disease. Although topical wound healing substances could promote rapid wound healing by preventing or reducing the consequences of inflammation, there still remains a need for the development of novel substances that can effectively reduce infection and inflammation in initial wound healing phase. In this study, collagen was combined with asiaticoside (AS) and ε-poly-l-lysine (εPLL).

Recent Advances in ROS-Responsive Cell Sheet Techniques for Tissue Engineering.

Cell sheet engineering has evolved rapidly in recent years as a new approach for cell-based therapy. Cell sheet harvest technology is important for producing viable, transplantable cell sheets and applying them to tissue engineering. To date, most cell sheet studies use thermo-responsive systems to detach cell sheets.

Stem cell passage affects directional migration of stem cells in electrotaxis.

Stem cells can differentiate into various body tissues and organs and thus are considered as promising tools for cell therapy and tissue engineering. Early passage stem cells have high differentiation ability compared to late passage stem cells. Thus, it is important to use early passage stem cells in cell therapy.

Effective stacking and transplantation of stem cell sheets using exogenous ROS-producing film for accelerated wound healing.

Extensive skin loss caused by burns or diabetic ulcers may lead to major disability or even death. Therefore, cell-based therapies that enhance skin regeneration are clinically needed. Previous approaches have been applied the injections of cell suspensions and the implantation of biodegradable three-dimensional scaffolds seeded cells.

Influence of Biomimetic Materials on Cell Migration.

In recent tissue engineering applications, the advance of biomaterials has focused on the devising of biomimetic materials that are directing new tissue formation and capable of causing specific cellular responses. These advances can be controlled by modifying the devising parameters of the materials. The biomimetic materials potentially mimic many roles of ECM in tissues.

Author Correction: Homogeneity evaluation of mesenchymal stem cells based on electrotaxis analysis.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.

Suppression of T24 human bladder cancer cells by ROS from locally delivered hematoporphyrin-containing polyurethane films.

Systemic injection of a photosensitizer is a general method in photodynamic therapy, but it has complications due to the unintended systemic distribution and remnants of photosensitizers. This study focused on the possibility of suppressing luminal proliferative cells by excessive reactive oxygen species from locally delivered photosensitizer with biocompatible polyurethane, instead of the systemic injection method. We used human bladder cancer cells, hematoporphyrin as the photosensitizer, and polyurethane film as the photosensitizer-delivering container.

Recombinant batroxobin-coated nonwoven chitosan as hemostatic dressing for initial hemorrhage control.

The choice of hemostat is determined by the situation and the degree of hemorrhage. One common hemostat, the nonwoven dressing, is easy to handled and controls severe bleeding on wider wounds. In this study, chitosan-based nonwoven dressings with recombinant batroxobin (rBat) were used as efficacious hemostatic dressing agents.

Exogenous ROS-induced cell sheet transfer based on hematoporphyrin-polyketone film via a one-step process.

To date, most of invasive cell sheet harvesting methods have used culture surface property variations, such as wettability, pH, electricity, and magnetism, to induce cell detachment. These methods that rely on surface property changes are effective when cell detachment prior to application is necessary, but of limited use when used for cell sheet transfer to target regions. The study reports a new reactive oxygen species (ROS)-induced strategy based on hematoporphyrin-incorporated polyketone film (Hp-PK film) to transfer cell sheets directly to target areas without an intermediate harvesting process.

Homogeneity evaluation of mesenchymal stem cells based on electrotaxis analysis.

Stem cell therapy that can restore function to damaged tissue, avoid host rejection and reduce inflammation throughout body without use of immunosuppressive drugs. The established methods were used to identify and to isolate specific stem cell markers by FACS or by immunomagnetic cell separation. The procedures for distinguishing population of stem cells took a time and needed many preparations.

Functional improvement of hemostatic dressing by addition of recombinant batroxobin.

Unlabelled: Although a number of natural materials have been used as hemostatic agents, many substances do not act quickly enough. Here, we created a novel dressings using collagen and chitosan with recombinant batroxobin (r-Bat) to promote faster and more effective hemostasis. We hypothesized that r-Bat would promote synergetic blood coagulation because it contains a blood coagulation active site different than those of collagen and chitosan.

Controlled Delivery of Extracellular ROS Based on Hematoporphyrin-Incorporated Polyurethane Film for Enhanced Proliferation of Endothelial Cells.

The principle of photodynamic treatment (PDT) involves the administration of photosensitizer (PS) at diseased tissues, followed by light irradiation to produce reactive oxygen species (ROS). In cells, a moderate increase in ROS plays an important role as signaling molecule to promote cell proliferation, whereas a severe increase of ROS causes cell damage. Previous studies have shown that low levels of ROS stimulate cell growth through PS drugs-treating PDT and nonthermal plasma treatment.

Ethyl-2, 5-dihydroxybenzoate displays dual activity by promoting osteoblast differentiation and inhibiting osteoclast differentiation.

The interplay between bone-forming osteoblasts and bone-resorbing osteoclasts is essential for balanced bone remodeling. In this study, we evaluate the ability of ethyl-2, 5-dihyrdoxybenzoate (E-2, 5-DHB) to affect both osteoblast and osteoclast differentiation for bone regeneration. Osteogenic differentiation of human mesenchymal stem cells (hMSCs) was quantified by measuring alkaline phosphatase (ALP) activity and calcium deposition.

Exovascular application of epigallocatechin-3-O-gallate-releasing electrospun poly(L-lactide glycolic acid) fiber sheets to reduce intimal hyperplasia in injured abdominal aorta.

Intimal hyperplasia is an excessive ingrowth of tissue resulting in chronic structural lesions commonly found at sites of atherosclerotic lesions, arterial angioplasty, vascular graft anastomoses, and other vascular abnormalities. Epigallocatechin-3-O-gallate (EGCG) was shown to elicit antioxidant, anti-proliferative, and anti-thrombogenic effects. In this study, we used an electrospinning technique to synthesize EGCG-eluting biodegradable poly(L-lactide glycolic acid) (PLGA) fiber sheets for local delivery of EGCG and investigated the effect of their exovascular application on intimal hyperplasia following balloon-induced abdominal aorta injury in a rabbit experimental model.

Titanium surface modification by using microwave-induced argon plasma in various conditions to enhance osteoblast biocompatibility.

Background: Titanium is a well proven implantable material especially for osseointegratable implants by its biocompatibility and anti-corrosive surface properties. Surface characteristics of the implant play an important role for the evolution of bone tissue of the recipient site. Among the various surface modification methods, plasma treatment is one of the promising methods for enhance biocompatibility.

Enhancement of human mesenchymal stem cell infiltration into the electrospun poly(lactic-co-glycolic acid) scaffold by fluid shear stress.

The infiltration of the cells into the scaffolds is important phenomenon to give them good biocompatibility and even biodegradability. Fluid shear stress is one of the candidates for the infiltration of cells into scaffolds. Here we investigated the directional migration of human mesenchymal stem cells and infiltration into PLGA scaffold by fluid shear stress.

Golgi polarization plays a role in the directional migration of neonatal dermal fibroblasts induced by the direct current electric fields.

Directional cell migration requires cell polarization. The reorganization of the Golgi apparatus is an important phenomenon in the polarization and migration of many types of cells. Direct current electric fields (dc (EF) induced directional cell migration in a wide variety of cells.

Control of neonatal human dermal fibroblast migration on poly(lactic-co-glycolic acid)-coated surfaces by electrotaxis.

Many types of cells respond to applied direct current electric fields (dcEFs) by directional cell migration, a phenomenon called galvanotaxis or electrotaxis. In this study, electrotaxis was used to control cell migration. We designed a new electrotaxis incubator and chamber system to facilitate long-term (> 12 h) observation and to allow for alterations to the direction of the current.

Ethyl-3,4-dihydroxybenzoate with a dual function of induction of osteogenic differentiation and inhibition of osteoclast differentiation for bone tissue engineering.

The current approach in biomaterial design of bone implants is to induce in situ regeneration of bone tissue, thus improving integration of the implants and reducing their failure. Therefore, ethyl-3,4-dihydroxybenzoate (EDHB), which stimulates differentiation of osteoblasts and the resultant bone formation, should be studied. In this study, the osteoinductive ability of EDHB in preosteoblasts and human mesenchymal stem cells was examined.

Resveratrol inhibits phenotype modulation by platelet derived growth factor-bb in rat aortic smooth muscle cells.

Dedifferentiated vascular smooth muscle cells (VSMCs) are phenotypically modulated from the contractile state to the active synthetic state in the vessel wall. In this study, we investigated the effects of resveratrol on phenotype modulation by dedifferentiation and the intracellular signal transduction pathways of platelet derived growth factor-bb (PDGF-bb) in rat aortic vascular smooth muscle cells (RAOSMCs). Treatment of RAOSMCs with resveratrol showed dose-dependent inhibition of PDGF-bb-stimulated proliferation.