Near‐Infrared Light‐Sensitive Polyvinyl Alcohol Hydrogel Photoresist for Spatiotemporal Control of Cell‐Instructive 3D Microenvironments

• Published in: Advanced materials (Weinheim) 2018-03, Vol.30 (10), p.n/a
• Main Authors: Qin, Xiao‐Hua, Wang, Xiaopu, Rottmar, Markus, Nelson, Bradley J., Maniura‐Weber, Katharina
• Format: Article
• Language: English
• Subjects: 3D cell culture; Cellular Microenvironment; Crosslinking; Direct laser writing; extracellular matrix; Hydrogels; Infrared radiation; multiphoton lithography; photoresists; Photosensitivity; Polyvinyl alcohol; Polyvinyl Alcohol - chemistry; Spatial resolution; Tissue Engineering; Ultraviolet radiation
• ISSN: 0935-9648; 1521-4095
• DOI: 10.1002/adma.201705564

Advanced hydrogel systems that allow precise control of cells and their 3D microenvironments are needed in tissue engineering, disease modeling, and drug screening. Multiphoton lithography (MPL) allows true 3D microfabrication of complex objects, but its biological application requires a cell‐compatible hydrogel resist that is sufficiently photosensitive, cell‐degradable, and permissive to support 3D cell growth. Here, an extremely photosensitive cell‐responsive hydrogel composed of peptide‐crosslinked polyvinyl alcohol (PVA) is designed to expand the biological applications of MPL. PVA hydrogels are formed rapidly by ultraviolet light within 1 min in the presence of cells, providing fully synthetic matrices that are instructive for cell‐matrix remodeling, multicellular morphogenesis, and protease‐mediated cell invasion. By focusing a multiphoton laser into a cell‐laden PVA hydrogel, cell‐instructive extracellular cues are site‐specifically attached to the PVA matrix. Cell invasion is thus precisely guided in 3D with micrometer‐scale spatial resolution. This robust hydrogel enables, for the first time, ultrafast MPL of cell‐responsive synthetic matrices at writing speeds up to 50 mm s−1. This approach should enable facile photochemical construction and manipulation of 3D cellular microenvironments with unprecedented flexibility and precision. A rapidly crosslinkable poly(vinyl alcohol) hydrogel photoresist is developed to synthesize modular 3D cell‐instructive microenvironments and to spatiotemporally control cell functions in culture via a multiphoton laser at high resolution. When cultured in 3D, single epithelial cells can self‐organize into miniature multicellular structures. This material allows ultrafast multiphoton photolithography and high‐precision cell manipulation in 3D culture, offering unprecedented opportunities for in situ tissue engineering and cell biology.