Katsuhisa Sakaguchi

In vitro scaling up of bioengineered tissues is known to be limited by diffusion issues, specifically a lack of vasculature. Here, we report a new strategy for preserving cell viability in three-dimensional tissues using cell sheet technology and a perfusion bioreactor having collagen-based microchannels. When triple-layer cardiac cell sheets are incubated within this bioreactor, endothelial cells in the cell sheets migrate to vascularize in the collagen gel, and finally connect with the microch

In the production of cell-based meat, it is desirable to reduce animal-derived materials as much as possible to meet the challenges of sustainability. Here, we demonstrate the "cell sheet-based meat": scaffold-free cell-based meat using cell sheet technology and characterize its texture and nutrients. Bovine myoblast cell sheets were prepared using temperature-responsive culture dishes (TRCDs) and 10 stacked cell sheets to fabricate three-dimensional tissue of 1.3-2.7 mm thickness. Hardness was

The development of microelectromechanical systems has resulted in the rapid development of polydimethylpolysiloxane (PDMS) microfluidic devices for drug screening models. Various cell functions, such as the response of endothelial cells to fluids, have been elucidated using microfluidic devices. Additionally, organ-on-a-chip systems that include organs that are important for biological circulation, such as the heart, liver, pancreas, kidneys, and brain, have been developed. These organs realize

Culturing three-dimensional (3D) tissues with an appropriate microenvironment is a critical and fundamental technology in broad areas of cutting-edge bioengineering research. In addition, many technologies have engineered tissue functions. However, an effective system for transporting nutrients, waste, or oxygen to affect the functions of cell tissues has not been reported. In this study, we introduce a novel system that employs diffusion and convection to enhance transportation. To demonstrate

Assembling three-dimensional (3D) tissues from single cells necessitates the use of various advanced technological methods because higher-density tissues require numerous complex capillary structures to supply sufficient oxygen and nutrients. Accordingly, creating healthy culture conditions to support 3D cardiac tissues requires an appropriate balance between the supplied nutrients and cell metabolism. The objective of this study was to develop a simple and efficient method for low-temperature c

Tissue engineering has attracted attention worldwide because of its application in regenerative medicine, drug screening, and cultured meat. Numerous biofabrication techniques for producing tissues have been developed, including various scaffold and printing methods. Here, we have proposed a novel tissue engineering method using a net metal mould without the use of a scaffold. Briefly, normal human dermal fibroblasts seeded on a dimple plate were subjected to static culture technique for several

Three-dimensional (3D) cardiac tissue reconstruction using tissue engineering technology is a rapidly growing area of regenerative medicine and drug screening development. However, there remains an urgent need for the development of a method capable of accurately measuring the contractile force of physiologically relevant 3D myocardial tissues to facilitate the prediction of human heart tissue drug sensitivity. To this end, our laboratory has developed a novel drug screening model that measures

Perfusable vascular structures in cell-dense tissues are essential for fabricating functional three-dimensional (3D) tissues in vitro. However, it is challenging to introduce functional vascular networks observable as vascular tree, finely spaced at intervals of tens of micrometers as in living tissues, into a 3D cell-dense tissue. Herein, we propose a method for introducing numerous vascular networks that can be perfused with blood into 3D tissues constructed by cell sheet engineering. We devis

Despite the increasing prevalence of Nonalcoholic steatohepatitis (NASH) worldwide, there is no effective treatment available for this disease. "Ballooned hepatocyte" is a characteristic finding in NASH and is correlated with disease prognosis, but their mechanisms of action are poorly understood; furthermore, neither animal nor in vitro models of NASH have been able to adequately represent ballooned hepatocytes. Herein, we engineered cell sheets to develop a new in vitro model of ballooned hepa

To establish a sustainable cultured meat technology, a low-cost culture medium must be developed without expensive biological materials such as serum and coating substances. However, even adhering bovine myogenic cells to uncoated culture dishes in the serum-free medium is challenging. We found that serum-free culture medium conditioned by HepG2 and NIH/3T3 cells not only accomplished the cell adhesion on uncoated culture dishes (the serum-containing medium : the serum-free medium : the conditio

The production of tissue-engineered skeletal muscles for cell-based therapy and cultivated meat production requires a large number of myogenic cells capable of differentiating into myotubes. A suspension culture with a stirred bioreactor is a system that is feasibly scalable, but scaling up the production of myogenic cells while maintaining differentiation capacity requires an efficient culture technique. This remains challenging in suspension culture. On the other hand, conventional meat proces

Tissues engineered utilizing biofabrication techniques have recently been the focus of much attention, because these bioengineered tissues have great potential to improve the quality of life of patients with various hard-to-treat diseases. Most tissues contain micro-tubular structures including blood vessels, lymphatic vessels, and bile canaliculus. Therefore, we bioengineered a micro diameter tube using alginate gel to coat the core gelatin gel. Micro-gelatin fibers were fabricated by the coace

The suspension culture system is an increasingly popular method of culturing cells not only because of its up scaling ability, but also the non-enzymatic procurement of cells that is crucial for biomedical research, especially in the fields of pharmacology and regenerative medicine. Hypothetically, by controlling and reducing the shear stress applied to cells in a culture system, the higher viability and proliferation rates. In this study, we analyzed HEK 293 cells cultured with a commercially a