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bioRxiv · 10.1101/2022.10.02.510557

Spatial cell fate manipulation of human pluripotent stem cells by controlling microenvironment using photocurable hydrogel

Abstract

Human pluripotent stem cells (hPSCs) dynamically respond to their chemical and physical microenvironment, dictating their behavior. However, conventional in vitro studies predominantly employ plastic culture wares, which offer a simplified representation of the in vivo microenvironment. Emerging evidence underscores the pivotal role of mechanical and topological cues in hPSC differentiation and maintenance. In this study, we cultured hPSCs on hydrogel substrates with spatially controlled stiffness. The use of culture substrates that enable precise manipulation of spatial mechanical properties holds promise for better mimicking in vivo conditions and advancing tissue engineering techniques. We designed a photocurable polyethylene glycol-polyvinyl alcohol (PVA-PEG) hydrogel, allowing for spatial control of surface stiffness and geometry at a micrometer scale. This versatile hydrogel can be functionalized with various extracellular matrix (ECM) proteins. Laminin 511-functionalized PVA-PEG gel effectively supports the growth and differentiation of hPSCs. Moreover, by spatially modulating the stiffness of the patterned gel, we achieved spatially selective cell differentiation, resulting in the generation of intricate, patterned structures. Summary statementA new hydrogel substrate enables spatial control of surface stiffness at the micrometer level, enabling local differentiation of hPSC and facilitating complex pattern formation.

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BibTeXRIS

WANG, Z., Numada, A., oda, y., Eiraku, M.. 2022-10-05. Spatial cell fate manipulation of human pluripotent stem cells by controlling microenvironment using photocurable hydrogel. https://doi.org/10.1101/2022.10.02.510557

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