Transplantable cell-encapsulation device using a semipermeable ethylene-vinyl alcohol copolymer membrane in a mouse diabetic model.

Cell-based therapy is an attractive approach, and encapsulation of therapeutic cells is a promising strategy because it prevents immune responses and allows transplanted cells to be retrieved in case of dysfunction. Bioartificial pancreas, in which insulin-secreting cells are encapsulated in a semipermeable membrane bag, is a new class of medical device for treating type-I diabetes. In this study, we developed a macroencapsulation device in which the pancreatic beta cell line MIN6 was encapsulated in a semipermeable bag made of an ethylene-vinyl alcohol copolymer membrane.

Expansion of human mesenchymal stem cells on poly(vinyl alcohol) microcarriers.

Microcarriers provide a high surface-area-to-volume ratio that can realize high yields of cell products, including human mesenchymal stem cells (hMSCs). Here, we report a novel poly(vinyl alcohol) (PVA)-based microcarrier for hMSC expansion in suspension culture. PVA microcarriers were prepared as collagen-coated PVA hydrogels 181 μm in size and a high surface-area-to-weight ratio of 2945 cm/g.

Massive and Reproducible Production of Liver Buds Entirely from Human Pluripotent Stem Cells.

Organoid technology provides a revolutionary paradigm toward therapy but has yet to be applied in humans, mainly because of reproducibility and scalability challenges. Here, we overcome these limitations by evolving a scalable organ bud production platform entirely from human induced pluripotent stem cells (iPSC). By conducting massive "reverse" screen experiments, we identified three progenitor populations that can effectively generate liver buds in a highly reproducible manner: hepatic endoderm, endothelium, and septum mesenchyme.

Quantitative measurement of damage caused by 1064-nm wavelength optical trapping of Escherichia coli cells using on-chip single cell cultivation system.

We quantitatively examined the possible damage to the growth and cell division ability of Escherichia coli caused by 1064-nm optical trapping. Using the synchronous behavior of two sister E. coli cells, the growth and interdivision times between those two cells, one of which was trapped by optical tweezers, the other was not irradiated, were compared using an on-chip single cell cultivation system.

Dynamics of yeast prion aggregates in single living cells.

Prions are propagating proteins that are ordered protein aggregates, in which the phenotypic trait is retained in the altered protein conformers. To understand the dynamics of the prion aggregates in living cells, we directly monitored the fate of the aggregates using an on-chip single-cell cultivation system as well as fluorescence correlation spectroscopy (FCS). Single-cell imaging revealed that the visible foci of yeast prion Sup35 fused with GFP are dispersed throughout the cytoplasm during cell growth, but retain the prion phenotype.