We established a method to fabricate a functional cellular nano-environment of induced pluripotent stem cells by a multi-layered nanofilm coating on the cell membrane.

Background: Micro-and nanoplastics (NPs) produced from the bulk fragmentation are rampant in the world by enormous plastic trash everyday life. NPs can be exposed to humans through a variety of routes, including inhalation and intake. The threat to humans from NPs is increasing invisibly. Nowadays, many people are concerned about human safety and health, but few are reported about the effects of NP on humans. To overcome the limitations in human studies, human induced pluripotent stem cells (hiPSCs) were used as an optimal in vitro platform to investigate developmental toxicology and subtle changes on cellular functions in terms of differentiation potential throughout a long-term culture.Results: Negatively charged polystyrene nanoplastics (PS NPs) were used to exclude acute toxic issues of surface charge and investigate the impact of the NP's size and nature during bioaccumulation. Intracellular observations revealed that NPs up to 1000 nm were over-internalized into single cells within 48 h, and smaller NPs demonstrated greater potency at decreasing number of viable cells by a strong correlation with the number of NPs on an equal mass basis. Also, PS NPs caused a signi cant reduction in self-renewal capacity of hiPSCs for 48 h. After the cells were exposed to PS NPs for 48 to 96 h at the beginning of the differentiation process, NPs accumulated in hiPSC did not render cellular functions vulnerable or adversely affect EB formation, EB-mediated differentiation, and neural lineage differentiation for up to 14 days. Conclusion:This study con rmed that hiPSC exposure to polystyrene nanoplastics results in acute toxicity and non-signi cant long-term effects on cellular functions. This report is important for understanding the developmental toxicology of nanoplastics and the origin of disease.

Summary Individual cell environment stimulating single cell is a suitable strategy for the generation of sophisticated multicellular aggregates with localized biochemical signaling. However, such strategy for induced pluripotent stem cell (iPSC)-derived embryoid bodies (EBs) is limited because the presence of external stimulation can inhibit spontaneous cellular communication, resulting in misdirection in the maturation and differentiation of EBs. In this study, a facile method of engineering the iPSC membrane to stimulate the inner cell of EBs while maintaining cellular activities is reported. We coated the iPSC surface with nanoscale extracellular matrix fabricated by self-assembly between vitronectin and heparin. This nano-coating allowed iPSC to retain its in vitro properties including adhesion capability, proliferation, and pluripotency during its aggregation. More importantly, the nano-coating did not induce lineage-specific differentiation but increased E-cadherin expression, resulting in promotion of development of EB. This study provides a foundation for future production of sophisticated patient-specific multicellular aggregates by modification of living cell membranes.

Background: Micro- and nanoplastics (NPs) produced from the bulk fragmentation are rampant in the world by enormous plastic trash everyday life. NPs can be exposed to humans through a variety of routes, including inhalation and intake. The threat to humans from NPs is increasing invisibly. Nowadays, many people are concerned about human safety and health, but few are reported about the effects of NP on humans. To overcome the limitations in human studies, human induced pluripotent stem cells (hiPSCs) were used as an optimal in vitro platform to investigate developmental toxicology and subtle changes on cellular functions in terms of differentiation potential throughout a long-term culture. Results: Negatively charged polystyrene nanoplastics (PS NPs) were used to exclude acute toxic issues of surface charge and investigate the impact of the NP's size and nature during bioaccumulation. Intracellular observations revealed that NPs up to 1000 nm were over-internalized into single cells within 48 h, and smaller NPs demonstrated greater potency at decreasing number of viable cells by a strong correlation with the number of NPs on an equal mass basis. Also, PS NPs caused a significant reduction in self-renewal capacity of hiPSCs for 48 h. After the cells were exposed to PS NPs for 48 to 96 h at the beginning of the differentiation process, NPs accumulated in hiPSC did not render cellular functions vulnerable or adversely affect EB formation, EB-mediated differentiation, and neural lineage differentiation for up to 14 days.Conclusion: This study confirmed that hiPSC exposure to polystyrene nanoplastics results in acute toxicity and non-significant long-term effects on cellular functions. This report is important for understanding the developmental toxicology of nanoplastics and the origin of disease.

Extracellular vesicles (EVs) composed of a lipid bilayer are released from various cell types, including animals, plants, and microorganisms, and serve as important mediators of cell-to-cell communication. EVs can perform a variety of biological functions through the delivery of bioactive molecules, such as nucleic acids, lipids, and proteins, and can also be utilized as carriers for drug delivery. However, the low productivity and high cost of mammalian-derived EVs (MDEVs) are major barriers to their practical clinical application where large-scale production is essential. Recently, there has been growing interest in plant-derived EVs (PDEVs) that can produce large amounts of electricity at a low cost. In particular, PDEVs contain plant-derived bioactive molecules such as antioxidants, which are used as therapeutic agents to treat various diseases. In this review, we discuss the composition and characteristics of PDEVs and the appropriate methods for their isolation. We also discuss the potential use of PDEVs containing various plant-derived antioxidants as replacements for conventional antioxidants.